408 Stroker Build Suggestions

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zsn0w

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Want some recommendations/advice on my build I'm starting up. I have the basics pretty much set, but some things (specifically the valvetrain) are still up in the air.
I'm aiming for a streetable car with a very good lowend that will be fun and fast but still drivable near daily. That being said, it doesn't have to be completely tame, just not looking for over 500HP or anything. I'm planning on using this kit Scat Engine Rotating Assemblies 1-98113BI for the rotating assembly as I want to be able to use it with pump gas and think the compression ratios look good here. For the intake I have an LD340 and I was planning on upgrading the carb to from my Holley 1850 I have laying around to a 750 CFM holley double pumper after saving up a bit. If this is overkill please let me know.
What I have questions about are head choices and valvetrain/camshaft options. I'm planning on keeping it a hydraulic flat tappet, and I was looking at Hughes SEH2428AL-11 and SEH2832AL-10 as options for the cam. My only problem with these is the questionable necessity of using all of the other hughes components. Pretty pricey for what, to me at least, seem like overkill for my usage. Could I use stock valvetrain components with this? Or at least stock-style summit lifters, springs, pushrods, etc? What other cams would you recommend? These cams seemed ideal in my research, but please let me know if I'm just completely barking up the wrong tree here.
On the topic of heads, I've been considering using 308's or maybe Edelbrocks if I can afford it and it's necessary. Would the 308s be a huge hindrance in a setup like this? Any input at all is appreciated. I have read a LOT about engine building but have not had much experience myself (yet), especially in the realm of V8s and pushrod valvetrains.
Thanks for your time and help!
 
Here is what I have:
1992 magnum block
Scat 4" stroke crank
Scat forged i-beam rods
Diamond flat top pistons (11.8:1 compression)
Total seal rings
Engine Pro main, rod, Cam bearings
Fluid damper
Cloyes double roller timing set
Cometic head gaskets
Edelbrock performer rpm heads (gasket matched w/ light porting)
Smith bros pushrods
Comp 1.5 ratio shaft mount billet roller rockers
Comp hydraulic roller lifters
Comp Cam
242/248 Dur@ .050, .3660/.3630 lift @ .050, 112° lobe sep. 549/544 gross valve lift
Comp valve springs, retainers, keepers, locators
ARP head studs
ARP bolts used throughout
Melling high volume oil pump
Edelbrock RPM Air Gap intake
MSD Pro Billet distributor
bronze dist gear
Taylor wires and looms
NGK plugs
Holley 750dp mech secondary manual choke
MSD 6AL-2 Programmable ignition box
Blaster2 Coil

It sits right at 500 hp and I run 93 octane pump gas. It is such a torque monster! I love this engine. It's not a great racer on the highway because at 80 mph the torque is not all there at that speed, but I never lose off the line. I've had it to 145 mph and had a lot to go. It's a great motor and you will never regret building it.
 
What is your:

Gear ratio
Tire size
Approximate RPM that the converter is stalling at
Car weight
RPM @ cruise

Thanks
Dana 60 with 4.10 gears
28" Nitto NT555R Extreme Drag Radials P275/60R15
3500 stall, though I originally had a 2500. I run a GM 200 4R overdrive transmission
car weight @ 3000-3200 lbs
With overdrive 3000 rpm at 80 mph
With OE 904 transmission 4000 rpm at 70 mph
 
20170211_155455.jpg
 
zsn
duplicate as much as possible the info given by Mopar to ya
get your head and compression nailed down before you buy a camshaft and etc
calculate your quench and try and get .030-.040 have that figured out and tentative gasket to get that dimension
what year block LA or Magnum and is it square already- check before spending $$$ because you do not know how much of a cut to square it up
did you specify LA shaft or Magnum Heads (and intake) just to be sure
have a straw man rocker picked out
unless you want to do B3 spacers forget roller tip and plan on adjustable Iron rockers preferably from Rocker Arm Specialists
read all 4 parts
B3 Racing Engines LLC - Mopar Rocker Arm Geometry Tech
get your head flows, straw man headers, compression figured out then fill out this form
Street Performance | Jones Cams
Best HR profiles IMHO
 
Dana 60 with 4.10 gears
28" Nitto NT555R Extreme Drag Radials P275/60R15
3500 stall, though I originally had a 2500. I run a GM 200 4R overdrive transmission
car weight @ 3000-3200 lbs
With overdrive 3000 rpm at 80 mph
With OE 904 transmission 4000 rpm at 70 mph
Oh I do like that build. Thanks!
That was some pertinent info!
His ride is a B body.

zsn
duplicate as much as possible the info given by Mopar to ya
get your head and compression nailed down before you buy a camshaft and etc
calculate your quench and try and get .030-.040 have that figured out and tentative gasket to get that dimension
what year block LA or Magnum and is it square already- check before spending $$$ because you do not know how much of a cut to square it up
did you specify LA shaft or Magnum Heads (and intake) just to be sure
have a straw man rocker picked out
unless you want to do B3 spacers forget roller tip and plan on adjustable Iron rockers preferably from Rocker Arm Specialists
read all 4 parts
B3 Racing Engines LLC - Mopar Rocker Arm Geometry Tech
get your head flows, straw man headers, compression figured out then fill out this form
Street Performance | Jones Cams
Best HR profiles IMHO
I do like your thinking.
Go to the B body forum to answer my PM will ya?
 
I run a smaller comp 274-S solid flat tappet cam and 9.7:1 compression, edelbrock “63cc” heads, scat kit: cast crank/I-beam/17cc Icon/balanced, M-1 single plane, 750+ cfm BG Silver Claw dbl,

Since you are looking for something real street freely I would limit yourself to 91 octane pump gas with 9.5-9.7:1 compression, flat tappet cam.

The heads and piston give me quench to help fight off detonation. If you need reduce compression, run the stock Fel Pro gasket that thicker. I run the thinner performance line gasket.

I think .500 NET lift is max for stock rockers. But stock rockers are 1.46:1 ratio. So you can get away with .515 or so advertised lift with flat tappet hydraulic cam

Add a edelbrock rpm intake, 750 dbl pump, TTI or Dougs headers... and you have 425-450 hp motor built economically that will fry street tires at will. Probably more.

I run ported heads, solid cam, comp roller rockers, bigger cam and single plane looking for a little higher power curves for when I occasionally go to the track and not dip below 3K rpm.
 
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I drive mine on the street - a lot. That's why I went with the 200 4R overdrive. I admit I street race any fool who tries and I do get to the track every now and then. I have a nitrous plate I haven't installed yet. I can't quite hit 11 seconds on just the motor. I figure the nitrous will get me low 11's to high 10's.
 
Want some recommendations/advice on my build I'm starting up. I have the basics pretty much set, but some things (specifically the valvetrain) are still up in the air.
I'm aiming for a streetable car with a very good lowend that will be fun and fast but still drivable near daily. That being said, it doesn't have to be completely tame, just not looking for over 500HP or anything. I'm planning on using this kit Scat Engine Rotating Assemblies 1-98113BI for the rotating assembly as I want to be able to use it with pump gas and think the compression ratios look good here. For the intake I have an LD340 and I was planning on upgrading the carb to from my Holley 1850 I have laying around to a 750 CFM holley double pumper after saving up a bit. If this is overkill please let me know.
What I have questions about are head choices and valvetrain/camshaft options. I'm planning on keeping it a hydraulic flat tappet, and I was looking at Hughes SEH2428AL-11 and SEH2832AL-10 as options for the cam. My only problem with these is the questionable necessity of using all of the other hughes components. Pretty pricey for what, to me at least, seem like overkill for my usage. Could I use stock valvetrain components with this? Or at least stock-style summit lifters, springs, pushrods, etc? What other cams would you recommend? These cams seemed ideal in my research, but please let me know if I'm just completely barking up the wrong tree here.
On the topic of heads, I've been considering using 308's or maybe Edelbrocks if I can afford it and it's necessary. Would the 308s be a huge hindrance in a setup like this? Any input at all is appreciated. I have read a LOT about engine building but have not had much experience myself (yet), especially in the realm of V8s and pushrod valvetrains.
Thanks for your time and help!
For the type of engine you are describing, i would highly consider contacting @Johnny Mac. He is a manager at blueprint engines. And he also owns a 10 second 408 dart. Wether you want a short block, or long block 408, you cant even buy the parts for what blueprintengines.com can sell you an assembled offering with a warranty, and dyno tested. Just my 2 cents. Lots of happy blueprint customers on the board.
 

Comments in the quote/click to expand

Want some recommendations/advice on my build I'm starting up. I have the basics pretty much set, but some things (specifically the valvetrain) are still up in the air.
I'm aiming for a streetable car with a very good lowend that will be fun and fast but still drivable near daily.See below
That being said, it doesn't have to be completely tame, just not looking for over 500HP or anything. I'm planning on using this kit Scat Engine Rotating Assemblies 1-98113BI for the rotating assembly as I want to be able to use it with pump gas and think the compression ratios look good here. For the intake I have an LD340 and I was planning on upgrading the carb to from my Holley 1850 Burry this one deep I have laying around to a 750 CFM holley double pumper, good choice after saving up a bit. If this is overkill please let me know.
What I have questions about are head choices and valvetrain/camshaft options. I'm planning on keeping it a hydraulic flat tappet, and I was looking at Hughes SEH2428AL-11 and SEH2832AL-10 ,as options for the cam.
I ran a Hughes 2430 for 4 years; and it made monster torque in my 10.9 Scr 367 cuber. But with cast-iron 308s your cylinder pressure might go thru the roof. Same for the 2832 . Because you have cubes, you won't be needing a torquey cam like one of these. (Hey This combo might be a prime candidate for a Thumpr type cam.) Don't skimp on the lifters. I have had excellent results with the Hughes I bought in 2004. These were not the base models but the better ones they were selling back then. With just a half turn preload, they go 7000 all day every day, withe Hughes 1110 springs, and never pump up, and never tic until the they need a lil adjustment, soooo, I highly recommend the Hughes lifters and springs.... plus adjustable arms.
My only problem with these is the questionable necessity of using all of the other hughes components. Pretty pricey for what, to me at least, seem like overkill for my usage. Could I use stock valvetrain components with this? Or at least stock-style summit lifters, springs, pushrods, etc? What other cams would you recommend? These cams seemed ideal in my research, but please let me know if I'm just completely barking up the wrong tree here.
On the topic of heads, I've been considering using 308's or maybe Edelbrocks if I can afford it and it's necessary. Would the 308s be a huge hindrance in a setup like this? Any input at all is appreciated. I have read a LOT about engine building but have not had much experience myself (yet), especially in the realm of V8s and pushrod valvetrains.
Thanks for your time and help!

It sounds to me like; for your stated useage,
"I'm aiming for a streetable car with a very good low-end that will be fun and fast but still driveable near daily."
That the 408 might be overkill....Hang on, I'm not trying to rain on your parade.
It's just that if your budget is that tight, I would swap the stroker in a heartbeat, for the aluminum heads. The 367 practically falls together at 10.8 Scr with 63CC Eddies. And together with .....say that SEH 2832, it would make cylinder pressure around 175psi, and you can run E87 on that; I do. You can't run that much pressure at all with iron heads. And if you put 63cc iron heads on the stroker,and use that same 2832 cam your pressure might go too high for pumpgas. But let's say you somehow get it down to 160psi. At that point and below 3000rpm, your 408 might show similar performance to a 367, also below 3000 rpm.................... so......... say 80% of the time or more, the 367 would be sufficient. The 367, at 175psi, will spin 275/60-15 BFG-TAs to 50/60 mph with 3.91/4.10s easy. It will spin 325/50-15 Comp T/As to the same. Actually, mine does it with a 4 speed and 3.55s, so second gear is 6.82 ratio for me, whereas for you; 6.82 would require 4.70s, before factoring in the TC; so say minimum 4.10s, to absolutely annihilate the tires..
But
Where the 408 will come in handy is in third gear......... sometime after 85 mph. You go there much? Another reason to run the 408, is so you can run a hiway gear,and still have a strong bottom-end left over, without running a monster TC. And another is cylinder pressure; you can soften it up to run pump gas and again; still have a tire fryer.
The only reason I mention these things is because you said;
"Any input at all is appreciated. I have read a LOT about engine building but have not had much experience myself (yet),Thanks for your time and help"; And because your budget is so tight.
Up here, Canada, the Eddies and proper valvegear cost me about $3000, back in 1999, while stroker kits were about $2000/2500. I have never been sorry about my decision.
Whatever you decide, forget that 1850, and
Happy HotRodding
 
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A ray of sunshine
Horsepower in in the heads no matter which cu in you come up with the top end HP will be what the heads can provide
the torque below max hp will be more with more cu in
you can add the high buck heads later or get your heads ported later- you want your heads to be pulling their max from low to max rpm
so build the bottom end with a reasonable compression ratio
I much prefer closed chamber so take a look at what's available- that rules out the X and J and 915 even the 308 but you can get some EQ heads for not much more than prep work on the old iron heads- or check out the budget aluminum ones- just stay away from the open chamber ones as as far as I spec you would need KB quench head pistons
of course you could go that rout with stock heads and mill of the quench dome when you changed heads- done that several times just to optimize quench
a consideration is that the later heads have a better combustion chamber- and the 308 is OK
sorry I misread your HFT spec- somewhere I saw HR
set up right I've run 550 lift with stock rockers but no reason to go over .500 with stock type heads-and that's with a good pro valve job otherwise the flatten out at .450 and at .550 you will need custom pushrods with stock rockers
no free lunch
did you post your gears and all the rest?
 
It sits right at 500 hp and I run 93 octane pump gas. It is such a torque monster! I love this engine. It's not a great racer on the highway because at 80 mph the torque is not all there at that speed, but I never lose off the line. I've had it to 145 mph and had a lot to go. It's a great motor and you will never regret building it.

That build sounds really nice. Pretty similar to what I want to end up with in a lot of ways, so thanks for all the info, I'll definitely be using it. Seems killer.

zsn
duplicate as much as possible the info given by Mopar to ya
get your head and compression nailed down before you buy a camshaft and etc
calculate your quench and try and get .030-.040 have that figured out and tentative gasket to get that dimension
what year block LA or Magnum and is it square already- check before spending $$$ because you do not know how much of a cut to square it up
did you specify LA shaft or Magnum Heads (and intake) just to be sure
have a straw man rocker picked out
unless you want to do B3 spacers forget roller tip and plan on adjustable Iron rockers preferably from Rocker Arm Specialists
read all 4 parts
B3 Racing Engines LLC - Mopar Rocker Arm Geometry Tech
get your head flows, straw man headers, compression figured out then fill out this form
Street Performance | Jones Cams
Best HR profiles IMHO

That calculator is awesome. I'm going to be filling that out tonight and seeing what it gives me. Thanks for the advice!

I run a smaller comp 274-S solid flat tappet cam and 9.7:1 compression, edelbrock “63cc” heads, scat kit: cast crank/I-beam/17cc Icon/balanced, M-1 single plane, 750+ cfm BG Silver Claw dbl,

Since you are looking for something real street freely I would limit yourself to 91 octane pump gas with 9.5-9.7:1 compression, flat tappet cam.

The heads and piston give me quench to help fight off detonation. If you need reduce compression, run the stock Fel Pro gasket that thicker. I run the thinner performance line gasket.

I think .500 NET lift is max for stock rockers. But stock rockers are 1.46:1 ratio. So you can get away with .515 or so advertised lift with flat tappet hydraulic cam

Add a edelbrock rpm intake, 750 dbl pump, TTI or Dougs headers... and you have 425-450 hp motor built economically that will fry street tires at will. Probably more.

I run ported heads, solid cam, comp roller rockers, bigger cam and single plane looking for a little higher power curves for when I occasionally go to the track and not dip below 3K rpm.

Pretty spot on to what I was wanting. It's nice to see all of these builds others have done and how awesome they turn out. 425-450 HP is pretty ideal, right around where I'd like to be. The rocker ratio information is super useful as well. Thanks!

For the type of engine you are describing, i would highly consider contacting @Johnny Mac. He is a manager at blueprint engines. And he also owns a 10 second 408 dart. Wether you want a short block, or long block 408, you cant even buy the parts for what blueprintengines.com can sell you an assembled offering with a warranty, and dyno tested. Just my 2 cents. Lots of happy blueprint customers on the board.

I have considered blueprint engines, but I think I'm going to build it on my own for this. Want to learn more about building V8s and the build itself is pretty enjoyable for me. Thanks for the suggestion, though.

It sounds to me like; for your stated useage,
"I'm aiming for a streetable car with a very good low-end that will be fun and fast but still driveable near daily."
That the 408 might be overkill....Hang on, I'm not trying to rain on your parade.
It's just that if your budget is that tight, I would swap the stroker in a heartbeat, for the aluminum heads. The 367 practically falls together at 10.8 Scr with 63CC Eddies. And together with .....say that SEH 2832, it would make cylinder pressure around 175psi, and you can run E87 on that; I do. You can't run that much pressure at all with iron heads. And if you put 63cc iron heads on the stroker,and use that same 2832 cam your pressure might go too high for pumpgas. But let's say you somehow get it down to 160psi. At that point and below 3000rpm, your 408 might show similar performance to a 367, also below 3000 rpm.................... so......... say 80% of the time or more, the 367 would be sufficient. The 367, at 175psi, will spin 275/60-15 BFG-TAs to 50/60 mph with 3.91/4.10s easy. It will spin 325/50-15 Comp T/As to the same. Actually, mine does it with a 4 speed and 3.55s, so second gear is 6.82 ratio for me, whereas for you; 6.82 would require 4.70s, before factoring in the TC; so say minimum 4.10s, to absolutely annihilate the tires..
But
Where the 408 will come in handy is in third gear......... sometime after 85 mph. You go there much? Another reason to run the 408, is so you can run a hiway gear,and still have a strong bottom-end left over, without running a monster TC. And another is cylinder pressure; you can soften it up to run pump gas and again; still have a tire fryer.
The only reason I mention these things is because you said;
"Any input at all is appreciated. I have read a LOT about engine building but have not had much experience myself (yet),Thanks for your time and help"; And because your budget is so tight.
Up here, Canada, the Eddies and proper valvegear cost me about $3000, back in 1999, while stroker kits were about $2000/2500. I have never been sorry about my decision.
Whatever you decide, forget that 1850, and
Happy HotRodding

You definitely had me considering the 367, but for my usage, I still think the 408 will be the way to go. I'm aiming for a lot of lowend, but I also want to be able to run highway-capable gearing so I can use the car a lot for normal driving. I also want to be able to use pumpgas. I think these lend themselves well to the stroker. On top of that, I'm going to need new pistons anyway if I'm boring out the cylinders .030, so I figure why not just go with the stroker kit? It's a huge increase in cubes and it really isn't that much more when I'm going to have to get the pistons and work done on the crank anyway. I also figure I can always upgrade the heads later to take better advantage of the bottom end if I need to. Leaning towards porting them later on or doing a light port now and going from there later possibly. Thank you for the advice, though. The 367 is definitely still a good choice for what I want, and if I wasn't aiming for exactly the use scenarios I am, I might have gone with that instead. I do value the input a lot, even if it's telling me not to do what I had planned, it's still really useful to see the other options that I hadn't even considered. On the topic of cams, I haven't really looked into the Thumprs all that much. Focused more on the other offerings from Comp, so I'll take a look at those for sure. Sounds like it could be a good fit, thanks!

A ray of sunshine
Horsepower in in the heads no matter which cu in you come up with the top end HP will be what the heads can provide
the torque below max hp will be more with more cu in
you can add the high buck heads later or get your heads ported later- you want your heads to be pulling their max from low to max rpm
so build the bottom end with a reasonable compression ratio
I much prefer closed chamber so take a look at what's available- that rules out the X and J and 915 even the 308 but you can get some EQ heads for not much more than prep work on the old iron heads- or check out the budget aluminum ones- just stay away from the open chamber ones as as far as I spec you would need KB quench head pistons
of course you could go that rout with stock heads and mill of the quench dome when you changed heads- done that several times just to optimize quench
a consideration is that the later heads have a better combustion chamber- and the 308 is OK
sorry I misread your HFT spec- somewhere I saw HR
set up right I've run 550 lift with stock rockers but no reason to go over .500 with stock type heads-and that's with a good pro valve job otherwise the flatten out at .450 and at .550 you will need custom pushrods with stock rockers
no free lunch
did you post your gears and all the rest?

This is what I am thinking about doing for the heads. Throwing the edelbrock heads on out of the box for now and porting them later once I've saved up more is looking like a solid option. What is the feasibility of using the SEH2832AL-10 with the edelbrock head springs and stock rockers until I can afford adjustable rockers to drop in later (thinking 1.6 might be better at that point, too, since looking at the flow numbers, I think the heads could use that extra lift enough to be worth the cost over the 1.5's)? My pushrods are toast, so I'll be buying new ones anyway (in addition to new lifters), but with adjustable rockers I should be able to use the same pushrods that I would use with stock rockers, correct? Getting all the gearing, weight, etc. information tonight. Got stuck at work a little late last night then had to catch up on some other stuff and there was a thunderstorm so I couldn't get outside to manually check the rear gears as I had hoped (I've got to jack the car up anyway to replace a parking brake cable, so I figure I might as well just count the driveshaft rotations to figure out the gearing while I'm down there). Thanks for the advice!
 
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I won’t put a hydr cam in a motor. Solid flat tappet would be fine for your hp goals. once it settles in doesn’t need much maintenance. The quality of the hydr lifters is such a crap shoot. But that does mean adjustable rockers. I have hammered on that kit for YEARS! The only difference is mine came with scat h beam rods which although nice may be overkill for your goals.
 
get away from cams till you get your compression and heads sorted out
a solid 274 was suggested but you would have to translate into hyd but what furrystump just said EDM solids are more bulletproof
the better the exhaust the less ex duration you will need
once you get the intake duration nailed down based on the Intake close point you need-for dynamic compression and AJ can help you there
and the duration based on the rpm range then you pick the exhaust and the LCA will be a result not an input
there are essentially a half dozen camgrinders to consider for hyd Comp only for the XExxxHL series, Howard, Lunati, Bullet, Engle
once You get close to a spec you can contact them- you are not there yet
Comp has NO Mopar optimised solid cams , add mike jones to the list if solid
and think iron adj rockers anyway
I see the target pistons are 30.5cc show your compression calcs
do your headwork
go to scat and get the compression height of the target piston and figure your deck clerance
 
I drive mine on the street - a lot. That's why I went with the 200 4R overdrive. I admit I street race any fool who tries and I do get to the track every now and then. I have a nitrous plate I haven't installed yet. I can't quite hit 11 seconds on just the motor. I figure the nitrous will get me low 11's to high 10's.

Are you running an 11 something on motor now?
 
zsn0w,

Do you run nitrous now? Or plan to with future motor? If so, scratch my recommendation for a cast crank. And from what you said in your last post, it seems like you plan (or have option to) bigger cam, ported heads, adjustable rockers.

-Scat forged crank balenced rotating assy: I-beam rods, Icon forged pistons -17cc dish w/quench pad
-9.5-9.7 compression
-Edelbrock 63cc heads
-stock rockers
-rpm intake
-hyd cam under .515 adv lift 230-236 @050
-750 dbl pump

Not rocket science
 
-Scat forged crank balenced rotating assy: I-beam rods, Icon forged pistons -17cc dish w/quench pad
-9.5-9.7 compression
-Edelbrock 63cc heads
-stock rockers
-rpm intake
-hyd cam under .515 adv lift 230-236 @050
-750 dbl pump

Not rocket science
I like the combo. And your right, it isn’t rocket science. It does just fall together right easy and well. Between the large displacement, good cylinder heads, easy in & out breathing manifolds, it will do well.
 
zsn0w,

Do you run nitrous now? Or plan to with future motor? If so, scratch my recommendation for a cast crank. And from what you said in your last post, it seems like you plan (or have option to) bigger cam, ported heads, adjustable rockers.

-Scat forged crank balenced rotating assy: I-beam rods, Icon forged pistons -17cc dish w/quench pad
-9.5-9.7 compression
-Edelbrock 63cc heads
-stock rockers
-rpm intake
-hyd cam under .515 adv lift 230-236 @050
-750 dbl pump

Not rocket science
Nah, I don't plan on using nitrous on it. I may take the car to the track for fun on rare occasions, but it's never going to be a track-focused or really even a track-influenced build. I would want under .515 lift because of the stock rockers, correct? So if I switched to adjustable that would change?
 
Going with adjustable rockers helps in a few ways. I wouldn’t limit my lift because I have new stamped steel OEM style rockers. Even more so with heads that flow well beyond a low .500 lift.

Your best bet is to take advantage of the heads air flowing capability and use a stronger true ratio rocker arm with a cam that has enough lift to get into the heads power making abilities.

The stamped rockers are not a true 1.5 ratio but a good rocker is! There are 1.6 ratios available for the LA engine.
 
Going with adjustable rockers helps in a few ways. I wouldn’t limit my lift because I have new stamped steel OEM style rockers. Even more so with heads that flow well beyond a low .500 lift.

Your best bet is to take advantage of the heads air flowing capability and use a stronger true ratio rocker arm with a cam that has enough lift to get into the heads power making abilities.

The stamped rockers are not a true 1.5 ratio but a good rocker is! There are 1.6 ratios available for the LA engine.
Yeah, I was figuring I'd go with 1.6 since a lot of the cams I was looking at would be around .55 with a 1.6, and the flow numbers I've seen on the edelbrock heads have it flowing higher up until around .6 or higher. I'm understanding this correctly, right? @autoxcuda was recommending the .515 lift due to the budget aspect of my build so that I could use stock rockers, I believe? But, if I bought 1.6 ratio rockers, would they need to be adjustable with a hydralic flat tappet cam? Or one of the pushrods or the rockers would need to be adjustable to make it work? Pushrods and rocker arms are the pretty much the things I understand the least, being much more used to OHC engines.
 
Nah, I don't plan on using nitrous on it. I may take the car to the track for fun on rare occasions, but it's never going to be a track-focused or really even a track-influenced build. I would want under .515 lift because of the stock rockers, correct? So if I switched to adjustable that would change?

You’ll gain a little lift. Not worth the $500 for comp roller rockers and another $125+ push rods. Factory iron adjustable rockers are 1.46. Rocker Arm Specialities can correct them, but that cost, initial cost, and shipping i’d guess at $300+ total.

I don’t think I’d bother with adj rockers and pushrods until you go to a bigger cam...OR just do all that now and spend money now.

I suggested stamped rockers worried that would take you $650 over budget. And suggested the smaller cam to go with that.
 
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A ray of sunshine
Horsepower in in the heads no matter which cu in you come up with the top end HP will be what the heads can provide
the torque below max hp will be more with more cu in

OP;This is spot on, so IMO your stroker with stock 308s, might best a 367 with Eddies in the HP war, but it sure won't be by much.
Here's a poser for those in the know (not me);
Op is looking for bottom end, so Compare;
a 408 with a 228/232/110 cam,unported 308 iron heads, and the Scr adjusted to yield 160psi;
to a 367 at 10.6Scr and ~175psi with OOTB Eddies.
I set the ICA to 65*, and the elevation to 450ft.
But wait, where does "bottom-end" start?
Let's say the stroker might be good for a 2500 and 3.23s, and
the 367 might like a 2800 and 3.55s.
Lets say the stroker makes 220ftlbs at 2500, and with 3.23s, and a 2.45 low, is laying down 1741 ftlbs, on the start line.
Lets say the 367 makes only 200 at 2800, and with 3.55s is laying down 1739.5 ftlbs.
See what I mean?
I'm just guessing at the numbers. It doesn't matter what the actual numbers are so long as the 10% split remains the same. eg if the stroker made 300 and the 367 made 272, it would still net the same result. So the only penalty is that the 367 cruises at 10% more hiway rpm.
In any case,1740ftlbs is way more torque than you need to break loose a pair of say 275/60-15 street tires. and Neither one of these combos is gonna be able to use WOT in first gear, below 35/40mph, without breaking the tires loose.
Now that was just two targets, namely off the line and cruising.
What about 3.23s versus 3.55s at lower speeds?
Well 3.23s will get you 60mph ~ 6000rpm at the top of first, for the stroker,so she is long past prime with the 308s and the 2832, so you'll wanna shift at say 5400, and that drops the Rs to 3200@54mph
3.55s will be 60~6600 for the 367, also in first, so some people might want to shift earlier but with the Eddies on there now and 1.6 arms, I say ride it out,lol; I always did. But say you wanna be fair. Well, the new shift rpm with the Eddies might be 5800, so that would be into second at 53mph@3420 Rs. Ok but if there is less than a 10% torque difference at those rpms,between these two engines, at the road; than the 367 could pull ahead.... see what I'm saying?
It's not always about cubes........ It's the whole combo

Plus the stroker will come in at around 10.5 Scr with 17cc cups,and 63cc chambers;and so about 170psi with that 2832 cam so you are gonna have to get rid of some of that pressure in order to be able to run pump gas...... and that is gonna be extra cost. Either the pistons will have to be scooped out, or a thicker head gasket used, which will mess up your Q; and so then you need a reverse dome piston, or an open-chamber head,and forget Quench .
Whereas the thrown together 367 with the same 63cc but aluminums now, is likely to run 175 psi with the same cam..... no extra machining, and has almost ideal Q of .040..
But yeah the stroker will make more dyno torque than the 367, I can't argue that. The thing is what can you do with it? The 367 already has more torque than the chassis, and the biggest tires you can fit in any stock A-body tubs,can handle, without a traction aider. So unless you wanna tow a 5th wheel trailer.......... that extra torque is all gonna go up in tiresmoke.

Now before you think I'm pushing 367 on you, I'm not. I'm simply offering an alternative to fit into your budget.

The thing that concerns me is how much is it gonna cost to get your compression LOW ENOUGH to run a 2832 and 308s. You add that onto the cost of the stroker kit; then compare that total to the installed and ready to go aluminum heads of your choice.
Don't forget to factor in the cost of gears and the TC, and the Trans will need some upgrades to live behind the stroker.
If you already own 3.23s and a 2500TC, and a beefed up trans;well then stroker is a no-brainer. But if you already own 3.55s and 2800 to 3000, then maybe the 367 is.
And then there is the long-term fuel costs. The aluminum headed-367 will burn 87E10 no problem. Even up to 185psi. What will you have to burn in the iron headed stroker at 160psi? This could add up to thousands of dollars over the life of the engine. My aluminum heads paid for themselves years and years ago.

BTW, you will need different pushrod ends with adjustable arms.
 
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We built a 408 for my brother in law, for his 68 Dart
Scat rotating assy with dished pistons pump gas friendly 10.2 to 1
RHS iron heads and 20 year old Hughes cam .565 lift, M1 intake and a quick fuel 850, 904 Trans
Engine runs great lot of low end power and runs out nice to 6500 rpms.

Car runs 11.10 on a warm day, cooler day 11.00, and i believe next year in the winter it will go 10.80s, having the right combo is very important.

20180106_101302.jpg
 
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