Junkyard BEAST!

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mshred

mshred

The Green Manalishi
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Well, just like the title says, im looking to build a junkyard motor that runs hard...My plans for a stroker have had a sharp curveball thrown at it, and in an effort to just get the car on the road but still have fun, here is what I have to work with...The faster I can go the better (im hoping something like this can see a mid 12, even faster great!:toothy10:).

-91 360 roller block...the bottom end is STONE stock. Bores still have good cross hatch, gonna do a home hone on them. Block will be getting cleaned, new bearings, new rings, stock pistons, rods (not sure if i should upgrade the bolts without resizing the big end...) and crank. no other machine work to keep costs down and block fresh for future stroker plans
-factory heads are cracked, going to go with Brians (IMM) Rhs heads or possibly stock edelbrocks if the springs can take the cam
-Airgap intake manifold with a holley 750HP carb on top
-1-5/8" headers into a 3" borla xr-1 race system (hopefully it will still sound good LOL)

My biggest questions are these

first, how much compression am I looking at with the stock dished pistons down in the hole? trying to figure out what chamber size i should order the RHS in for this build but still be able to use them in a future stroker build. Pump puke will obviously not be a problem (87 baby!:toothy10:). Was thinking Mopar head gasket P4120094 (compressed thickness of .024-.028") to get compression up...anything to be gained by reversing the pistons, or should i not waste my time?

My second question is what cam. This is a factory roller block, factory roller lifters are still good. So, in staying with the theme of max performance out of this, what kind of cam? I know COMP offers a few decent grinds, Lunati just came out with some nice more aggressive roller lobe profiles, etc...Just wondering spec wise what I would be looking at to make the most power while still sounding quite nasty and running pump gas i.e. dur at .50, lift, lsa, etc..

All of this in my 3200lb scamp with 4.10's in a dana, a 4 speed, and caltracs with an e/t street...im really hoping a mid 12, should still be a blast and should put a smile on my face for how cheap it was lol

sooo, what say ya'll???? I need to hear suggestions, this is a totally new game that i have no idea where to start with:toothy10: searching the word junkyard on here didnt help so much lol
 
You know, we just brought up that junkyard 360 Hot Rod did a few years back in another thread. You could do somethin like that. Mild engine with like a 250 plate shot. It would be fun. They literally took one outta a junkyard, tried to blow it and couldn't. That Duster it was in was haulin *** though.
 
StrokerScamp said:
You know, we just brought up that junkyard 360 Hot Rod did a few years back in another thread. You could do somethin like that. Mild engine with like a 250 plate shot. It would be fun. They literally took one outta a junkyard, tried to blow it and couldn't. That Duster it was in was haulin *** though.
Click to expand...

you are definitely right about that, but this is a street car first and foremost, so its gotta have some balls off the giggle gas too...once ive maxed out its junkyard-a-bility on the motor maybe then ill get crazy and throw a plate on it lol:toothy10:

the way im lookin at the whole thing, even though i wont be as fast as my original plan, it will be quite fun seeing how much i can squeeze out this way...so im open to suggestions guys
 
this has been a hot topic lately it seems like. I have an 86 360 with an aluminum performer and holley 650dp. I dont have a ton of money like most young guns on here so Im real interested to see what people have to say.
 
You want me to design you somethin on my computer dyno? gimmie some parameters...like what you want out of it.
 
I like this build hypothesis.
Its very similiar to my own.

I could offer some input.
You will need to figure your estimated Compression Ratio.
That will require CC'ing the dish in the pistons, and the Combustion chamber of the heads you will be using.

Once you verify your CR is over 8.5:1 (stock advertised CR...btw)

I would recommend a camshaft that has a split duration grind on the Intake and Exhaust.

The Cam Card grind should read like:

224I/232E @ .050 .540"I/.550"E 112*

I would use a windage tray if you dont already have one.
I would install a NEW double roller timing chain and NEW HV oil pump.
I used a late model timing chain tensioner on my 360 to see if there were solid gains there...like more stable ignition timing....so,....food for thought.

Then, have the heads gasket matched, the intake gasket matched, and use a FULL 2.5" Dual exhaust system, and it should make over 350rwhp.

Good for mid 12's if you can hook it up and put it down.
 
StrokerScamp said:
You want me to design you somethin on my computer dyno? gimmie some parameters...like what you want out of it.
Click to expand...

well i dont want to sound like a lazy bum, but its more cam selection im after and if i can get decent compression out of this thing. I still want it to have a rough idle and give me some good performance..If this thing hits a mid 12 in junkyard form ill be very pleased...faster, hell even better:thumleft:

no stock head stuff either. Brian's RHS or im even thinking now of some eddy aluminums, although obviously flow is down quite a bit from the RHS

I just dont know where to begin with it being a low compression build- not sure what changes in terms of cam choice over something with say 10.5:1 and .040" quench that i was going for before

caferacerx said:
$199 hughes roller cam
http://www.hughesengines.com/Index/...nbnVtICgzLjkvNS4yLzUuOSk=&level1=Q2Ftc2hhZnQ=
Click to expand...

i like this one, except with maybe more lift to utilize all RHS heads have?...http://www.hughesengines.com/Index/...el2=V2hpcGxhc2ggSHlkLiBSb2xsZXI=&partid=26252

mopardude318 said:
you gonna use a set of Hughes roller rockers on those RHS heads?
Click to expand...

LOL you really love those things eh...all kidding aside, it looks like i probably will. My plan is to do the top end and rest of the motor the way i want to, but leave the bottom end stock for now. Then later on when I have the money, i can buy the bottom end to stroke it and already have the top end to support it (and a cam change to realize the full power gains of a new combo)

Prine said:
I like this build hypothesis.
Its very similiar to my own.

I could offer some input.
You will need to figure your estimated Compression Ratio.
That will require CC'ing the dish in the pistons, and the Combustion chamber of the heads you will be using.

Once you verify your CR is over 8.5:1 (stock advertised CR...btw)

I would recommend a camshaft that has a split duration grind on the Intake and Exhaust.

The Cam Card grind should read like:

224I/232E @ .050 .540"I/.550"E 112*

I would use a windage tray if you dont already have one.
I would install a NEW double roller timing chain and NEW HV oil pump.
I used a late model timing chain tensioner on my 360 to see if there were solid gains there...like more stable ignition timing....so,....food for thought.

Then, have the heads gasket matched, the intake gasket matched, and use a FULL 2.5" Dual exhaust system, and it should make over 350rwhp.

Good for mid 12's if you can hook it up and put it down.
Click to expand...

Hey Prine, yes, when i was thinking of this i remembered your build. Im going to cc the pistons, but atleast i know what its advertised at (Thanks!). Just gotta figure out how far down in the hole they are as well, and then factor in gasket thickness, and i can truly figure compression

That cam you recommended looks good, except im not sure it will give me the idle im looking for. Seems like quite a low duration number and a wide lsa (is that because of the compression?)...I dont mind spinning this motor to 6500rpms if i have to, so that is not a concern

Motor will be getting all the basic parts of a rebuild- its stock windage tray bac, new ported oil pump, pickup tube, double roller timing set, rings, bearings, etc.

Im hoping a mid 12 is doable since the chassis is setup to run faster- caltracs with 9 way ranchos, /6 torsion bars with calvert 90/10's and RMS UCA's up front...should be a surprising combo if i can get it to run
 
i've built a 360 from a 78 block, .030" bore, no extra stroke, KB 10.5:1 compression pistons, mopar purple cam w/ .484" lift 283 duration, factory big port heads, shorty tube headers and factor hi-po heads, makes about 400hp, for a lighter, maybe more powerful engine i'd try finding a wrecked dakota or durango r/t and stealing its heads and converting it into a magnum motor, although i personally prefer LA style valvetrains
 
Some of my most fun engines were those... We called them Krylon rebuilds. Stock everything (not even re-ringing), clean and lap the valves, replace the valve seals, stick some single w/dampner springs on the heads, a smallish cam, intake, carb, and paint it. Some on Ebay still consider this a full rebuild :).
 
I'll add, I wouldnt use the hydraulic roller cam. I'd put a solid flat tappet in it to try and get as much low end and a good torque curve out of it. If you have to, call Bullet and get a custom cam. The static ratio with factory heads is in the 7.4:1 range, so with the smaller chambers and thin head gasket you're still only looking at around 8.5:1 static.
 
moper said:
I'll add, I wouldnt use the hydraulic roller cam. I'd put a solid flat tappet in it to try and get as much low end and a good torque curve out of it. If you have to, call Bullet and get a custom cam. The static ratio with factory heads is in the 7.4:1 range, so with the smaller chambers and thin head gasket you're still only looking at around 8.5:1 static.
Click to expand...

Hey moper, i figured staying with the hydraulic roller would just help in terms of reliability. By the time i buy a solid cam and lifters, im looking at close to 300 bucks, and a hydraulic roller is only 20 bucks more (I already have the lifters).

I really dont want to touch the bottom end at all since I want to direct that money into peicing together the new rotating assembly for the future. With such low compression though, what cam specs do you recommend? Id really like to stick with a shelf cam if possible to minimize cost but still come out with something that performs decent and idles mean. Also, with the low compression and th RHS heads, will I be able to spin this motor up, or will it fall on its face?

Please guys, feel free to recommend a cam to me, i want to stick with a shelf grind if possible:thumleft:
 
mshred, haven't we been down this road before lol, I'm sure i gave you the rundown on my 71 "no thrills" 71 Swinger, junkyard 360 magnum, RHS heads, re-ground roller from bullet, Crosswind intake, 650dp. 3.73 gears & a 2800 11" converter, drove it too & from the track (100 miles round trip) several times & pulled off 12.5s shifting at 5100 RPM, With a converter change & some more tinkering i'm sure 12.3s were there, thats flyin for what it was, a NON stripped all steel/glass 71 Swinger, granted i'm a light weight at 145 lbs., so that helps, I ran a Sniper system pilled for 125, on my best run (but still not great) I pulled off a 7.58 @ 94 & change, I personally would run a Roller, **** all that flat tappet ****, sorry Moper, I also ran the thick factory head gasket with the factory pistons, my compression was close to 9.1, If you want to know more about doing something like this & ideas, talk with LXguy, His factory dressed 71 Swinger runs 11.7s with a "junkyard" 360 magnum short block.
 
JoeDust451 said:
mshred, haven't we been down this road before lol, I'm sure i gave you the rundown on my 71 "no thrills" 71 Swinger, junkyard 360 magnum, RHS heads, re-ground roller from bullet, Crosswind intake, 650dp. 3.73 gears & a 2800 11" converter, drove it too & from the track (100 miles round trip) several times & pulled off 12.5s shifting at 5100 RPM, With a converter change & some more tinkering i'm sure 12.3s were there, thats flyin for what it was, a NON stripped all steel/glass 71 Swinger, granted i'm a light weight at 145 lbs., so that helps, I ran a Sniper system pilled for 125, on my best run (but still not great) I pulled off a 7.58 @ 94 & change, I personally would run a Roller, **** all that flat tappet ****, sorry Moper, I also ran the thick factory head gasket with the factory pistons, my compression was close to 9.1, If you want to know more about doing something like this & ideas, talk with LXguy, His factory dressed 71 Swinger runs 11.7s with a "junkyard" 360 magnum short block.
Click to expand...

Joe, I read you sold the dart? how come

And yes we have been down this road before lol.. I actually called bullet but about a cam for my other build that was going to be more radical. What did your cam spec out at? I want something thats gonna give me the most power i can get with my low compression and still give me a rough sounding idle (that is a must for me lol)

I think ill pm LXguy as well, or maybe he'll chime in here.

what cam specs do you suggest for what I am after..Im playing with camquest right now trying to get an idea which of their cams wil work best for me
 
mshred said:
Joe, I read you sold the dart? how come

And yes we have been down this road before lol.. I actually called bullet but about a cam for my other build that was going to be more radical. What did your cam spec out at? I want something thats gonna give me the most power i can get with my low compression and still give me a rough sounding idle (that is a must for me lol)

I think ill pm LXguy as well, or maybe he'll chime in here.

what cam specs do you suggest for what I am after..Im playing with camquest right now trying to get an idea which of their cams wil work best for me
Click to expand...

My cam was "mild", It was all that could be done with the factory stick, It ended up being (with 1.6 rockers) .477/.477, .218/.218 @50 on a 112, i'm sure you will want more, this cam was a torque monster with stock compression, I would contact Hughes or Bullet or even Brian, you will most likely need an new cam & have it ground to your likeing, now if your planning on useing Brians RHS heads, talk with him, you can always mills the heads a tad (.020" or so) & run the thinner head gasket, this should get compression up around 9.5, then you can run alittle better cam, I personally think 1 with a 109/110 LSA & Dur. in the upper 220s/ lower 230s, lift around 530/540 would run VERY strong. I think theres one from Comp. that Brian seems to like, give him a ring. :thumleft:
 
can anybody actually recommend a shelf grind from comp for this?

Was playing with camquest a little and was thinking one of these
XR274HR-10
dur at .50 224/230
Lift 538/534
LSA 110
RPM range 1800-5800

Or this one, a little more aggressive...says it needs 9.5:1 compression, dont think ill get that though
XR280HR-10
Dur 230/236
lift 541/537
LSA 110
rpm range 2200-6000rpm

both are hydraulic rollers...not sure if im on the right track though?
 
I am not a cam expert as you know, but take a look at the 20-745-9 or the 20-746-9 cams. Looking at the dyno graphs these two cams make more torque and are flatter and longer, not as peaky as the ones you were looking at. I'm thinking that the torque will push that BEAST more and not drop off as quickly. I am not sure what the idle quality will be like though. Both will work up to 6000.

onig
 
IMO, the cams with less of a split duration will work better in a ported head. The larger split cam, like Prine recomended, will work better with stock heads. I would use a cam like prines with 10* more duration. Like the factory crate motor roller cam would be nice.

Try and get to a 9.0-1 ratio like the create motors are. If I could, mix a "LA" cam with Magnum rocker heads and ratio for a quicker valve lift and intencity of the cam. The stock heads should be a starting point IMO just to save money on the starting point and to get going down the road quicker. Save the $1,000 or so bucks on the other heads till later. Mill the stockers. Get going first.

Create engines in A bodies are known for mid 12's OOTB (well tuned and dailed in along with the chassis) in full dressed cars. Have seen low 12's with moderatley striped cars. 2 or 3 people I have witnessed run into the high 11's with the drag race only car.
 
No biggie on the cam Joe. I don't have problems with flat tappets and frankly, I'm not all that impressed with the hydraulic rollers. They will always be limited to a ramp speed no faster than a hydraulic flat tappet and simply put, the solid flat tappet will be more streetable and make more power for every given size. Just out of curiousity, what did your car run off the bottle?
I've watched a friend run 12.30s in his all steel Dart running 360, 3.91s and a 9.5" convertor that flashes to 2500. The 360 was a 9:1 LA based 360, the MP solid (.528 lift, .488 at the valve after lash), an M1 single plane and a Holley 750. No nonsense. Not expensive. And it has run it since the mid 90s.
I'd be looking at a flat tappet solid shelf grind. Something like the XE268s which doesnt need a terribly heavy spring and will not only rpm but have a very solid torque curve. Something that doesnt need a high stall to work well.
 
Engine Quest has great replacement heads too. (And cheeper than RHS)
 
onig said:
I am not a cam expert as you know, but take a look at the 20-745-9 or the 20-746-9 cams. Looking at the dyno graphs these two cams make more torque and are flatter and longer, not as peaky as the ones you were looking at. I'm thinking that the torque will push that BEAST more and not drop off as quickly. I am not sure what the idle quality will be like though. Both will work up to 6000.

onig
Click to expand...

The first cam is milder than what I have in the 340 now, and the second barely more. Although more torquey, I really want something that will take advantage of the lift in the heads. Im thinking the second cam i listed will be right where I want the car in terms of idle, power, and rpm range. but im no expert either lol;-)

onig said:
Your sig.
C.O.T.L.O.D.????
Click to expand...

[ame="http://www.youtube.com/watch?v=-YAZrCfgZzU"]YouTube - Testament - C.O.T.L.O.D.[/ame]

rumblefish360 said:
IMO, the cams with less of a split duration will work better in a ported head. The larger split cam, like Prine recomended, will work better with stock heads. I would use a cam like prines with 10* more duration. Like the factory crate motor roller cam would be nice.

Try and get to a 9.0-1 ratio like the create motors are. If I could, mix a "LA" cam with Magnum rocker heads and ratio for a quicker valve lift and intencity of the cam. The stock heads should be a starting point IMO just to save money on the starting point and to get going down the road quicker. Save the $1,000 or so bucks on the other heads till later. Mill the stockers. Get going first.

Create engines in A bodies are known for mid 12's OOTB (well tuned and dailed in along with the chassis) in full dressed cars. Have seen low 12's with moderatley striped cars. 2 or 3 people I have witnessed run into the high 11's with the drag race only car.
Click to expand...

Well it seems the single pattern grinds are usually in the lower lift ranges, but I will look again. Unfortunately my stock heads are cracked and unusable, and to get a set reconditioned is about 200 dollars cheaper than stepping up to the RHS. Im also building this topend for the future in terms of heads and rockers, so i know the RHS stuff will support a stroker that im going to collect parts for, and will definitely only help my current combo. I also wanted to go LA valvetrain style to stick with the shaft mount stuff since it should (technically) be more stable at higher lifts. Although the magnum choices and price in rocker gear is attractive

Im hoping with the combination of the 62cc chambers, the composite mopar head gaskets with a .024-.029" compressed thickness will get me atleast an 8.5:1, if not a 9:1. This is going to be low buck of low buck, bone stock bottom end.

one thing i gotta ask though...create engines? LOL
 
moper said:
No biggie on the cam Joe. I don't have problems with flat tappets and frankly, I'm not all that impressed with the hydraulic rollers. They will always be limited to a ramp speed no faster than a hydraulic flat tappet and simply put, the solid flat tappet will be more streetable and make more power for every given size. Just out of curiousity, what did your car run off the bottle?
I've watched a friend run 12.30s in his all steel Dart running 360, 3.91s and a 9.5" convertor that flashes to 2500. The 360 was a 9:1 LA based 360, the MP solid (.528 lift, .488 at the valve after lash), an M1 single plane and a Holley 750. No nonsense. Not expensive. And it has run it since the mid 90s.
I'd be looking at a flat tappet solid shelf grind. Something like the XE268s which doesnt need a terribly heavy spring and will not only rpm but have a very solid torque curve. Something that doesnt need a high stall to work well.
Click to expand...

Moper, if you had to, what do you recommend in the hydraulic roller realm of cams? I don't even know if this motor will rpm (have no idea if low comp motors are limited in that regard?) I already have the roller lifters and would love to be able to use off the shelf synthetic oil instead of trying to hunt down old rotella and using additive

Also, im really hoping that I can get 9:1 compression. My block is a 91 LA, not sure what they came with from the factory in terms of compression. your friends combo sounds similar to mine except ive got an air gap manifold and 4.10's with the 4 speed

If my combo ran that good id be exatic...what heads is he using and what is he shifting at?

Mr Hemi said:
How far are those pistons down the hole (deck height )?
Click to expand...

Im not sure to be honest. I took the engine apart without even measuring since plans were different when i was disassembling

I have also looked at the EQ heads, and they are great for the price. I just like how Brian sets his up, and for the price and performance they are hard to beat, especially for use in the future:thumleft:
 
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