Building a stroker, advice please

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11.2

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I've been running a 360/408 for three years now, I always planned on doing the gen III conversion but I've finally faced reality and it will never happen. So I want to upgrade to a steel crank and roller cam, it just so happens a local gentleman Is willing to give me a decent price on my shortblock so I will build a new one and reuse my top end, here's some info
340 virgin block
Ported Eddie heads with port matched rpm intake
Fast ez efi
Msd e curve in conjunction with 6a ignition
518od tranny
3.91 gears

My goal is 550ish hp and trying to stay under 3000 rpm stall and pump gas.
wich stroker kit is the hot ticket these days, scat? Eagle? I've heard about coated Pistons, is there any disadvantages ? Any advise is appreciated including oil pumps, oil pans with best clearance, timing chains.... U name it
 
Brian at IMM. Is, like, totally hot. I hear the scat stuff fits well also.
 
Do you have any flow info on the RPMs? 550hp is a lot to ask from them unless they've had some decent work done. Honestly I've never recommended a stall over 2500 for a stroker. You don't need a higher stall with them unless you're racing it first and foremost.
 
moper said:
Do you have any flow info on the RPMs? 550hp is a lot to ask from them unless they've had some decent work done. Honestly I've never recommended a stall over 2500 for a stroker. You don't need a higher stall with them unless you're racing it first and foremost.
Click to expand...
What heads would you reccomend if not the ported Eddies ?
 
I don't think you'll hit 550 hp with an RPM intake but you might get close. Here is a 427 that I built a few years ago. We made about 520 hp with a small cam and a 650 carb so there was room to make more power. But, if you go with a bigger cam and carb then you start to give up torque on the bottom end so you have to decide where you want the power.

http://www.hotrod.com/how-to/engine/mopp-1106-1968-plymouth-valiant-427-engine-swap/
 
I've gotten 530 from RPMs that flowed 285 at the cams peak lift and a small street solid roller. Another 20-30 degrees at .050 and .030-.040 lift would have done it. But everything better be perfect...

You can use ported RPMs. But there's correctly well ported, and "ported". The key is realistic flow numbers. That's why I asked what you had. In a compromise street engine to get a true 550hp in a chassis you better have 275-280 at your cam's peak lift or you won't make it. Some heads will get there at .550 lift. Some will need to go to .600 or more. Personally I think a set of ported -1 Indys would be a better choice and not have to use such a large camshaft. Also remember if you're racing a dyno number you'll lose a solid 10% or more at the crank just by installing it in a chassis with full exhaust and belt driven accessories.
 
AndyF said:
I don't think you'll hit 550 hp with an RPM intake but you might get close. Here is a 427 that I built a few years ago. We made about 520 hp with a small cam and a 650 carb so there was room to make more power. But, if you go with a bigger cam and carb then you start to give up torque on the bottom end so you have to decide where you want the power.

http://www.hotrod.com/how-to/engine/mopp-1106-1968-plymouth-valiant-427-engine-swap/
Click to expand...



Unfortunately, I have to stick with the rpm due to hood clearances
 
i cant seem to find my specs for my heads after porting and don't remember the exact numbers but I will phone the guy who ported them tomorrow and post.
 
11.2 said:
Unfortunately, I have to stick with the rpm due to hood clearances
Click to expand...

You lost me there. The RPM is a tall intake why are you sticking with it if you have hood clearance issues? Have you ever measured a Victor intake?
 
moper said:
Do you have any flow info on the RPMs? 550hp is a lot to ask from them unless they've had some decent work done. Honestly I've never recommended a stall over 2500 for a stroker. You don't need a higher stall with them unless you're racing it first and foremost.
Click to expand...
I would recommend a stall around his peak torque. Why build a 550hp motor and handcuff it with a low stall? I run a dynamic 4,400rpm stall in my 360 and it's like a stock converter until you really start to put your foot into it. I guess if he's going to use bfg radial T/A's then I see your point, but then my little low HP 360 with J headed, 4,400 stall and drag radials will kick that 550 HP slug ...
 
AndyF said:
You lost me there. The RPM is a tall intake why are you sticking with it if you have hood clearance issues? Have you ever measured a Victor intake?
Click to expand...

Yes, it is a full inch taller
 
I think you'll be able to get your horsepower goal.

Though we did use the Edelbrock Victor intake on the BPE 424/360 we built. This engine used our ported RaceMaster/ProComp cylinder heads that flowed 290cfm @ .600". Used a 950 cfm 4150 4-bbl, solid roller cam that had .638/.645 lift, 10.7:1 compression. 456 lb-ft of torque @ 3,200 rpm, 503 lb-ft of torque @ 4,200 rpm and 562 lb-ft @ 4,900 rpm. 549 hp @ 5,300 rpm and 601 hp @ 6,300 rpm. Drives around the street very nice with 3.23 gears, 727 transmission and a 3,200 stall converter.


Traction is a little scarce.

EDIT:

Okay, I blew it and confused things. I was thinking of the two Victor manifolds, Victor 340/360 and Super Victor and referred to the Super Victor as the Victor. We ran the Super Victor and not the Victor 340/360
 
EL5DEMON340 said:
Why build a 550hp motor and handcuff it with a low stall?
Click to expand...


Have you driven one? You have to remember that while your 360 might be making 180 pound feet at 2200 the 550hp 408 will be making well beyond 300. These engines don't really have a "peaky" torque peak. It's a fairly flat or gently rounding curve that starts at a higher number at very low rpm. You simply don't need all that inertia or multiplication from a high stall, and most of these cars will not have the traction to hold it anyway.

"Traction is a little scarce."
^^ understatement.
 
If you want traction on the street with a 15" tire that's "V" rated, install a set if Nitto Drag Radials. They make both my cars safe to drive on the street. They last a long time too.
 
Torque is what the stroker is good at it too. Easy to be at or above 400 lbft by 3K.
 
moper said:
Have you driven one? You have to remember that while your 360 might be making 180 pound feet at 2200 the 550hp 408 will be making well beyond 300. These engines don't really have a "peaky" torque peak. It's a fairly flat or gently rounding curve that starts at a higher number at very low rpm. You simply don't need all that inertia or multiplication from a high stall, and most of these cars will not have the traction to hold it anyway.

"Traction is a little scarce."
^^ understatement.
Click to expand...

Yep traction is a little scarce, I will plead guilty on picking on BB &. SB cars that are stroked, and are pushing hi HP without the other mods nessasary to put it to the ground !!! LOL
 
FredS said:
Torque is what the stroker is good at it too. Easy to be at or above 400 lbft by 3K.
Click to expand...

my 408 puts out 440 lbft at the 3K mark :D



from MRLs website :

Back to the Future! 2015 is a dawn of a new era.


We have made some real progress on this setup. After doing dozens of them, tweaking along the way this is the New Standard of Mopar Power! Same cam as before, our hydraulic roller cam with 239/243 duration at .050" lift. Valve lift is .550/.560". Compression is 10 to 1. All the same as before. Same heads, same pistons, rods, crank. Now for the CHANGES! We have some new chamber mods that are doing well. So well in fact that we now are running 4-6* LESS timing than before. That's a good thing. It shows we are running with a better flame travel. The other BIG change on this combo is the addition of a FAST EZ EFI 2.0 T-body injection system, with dual sync dist and full ECU timing control. This is the ticket. Its all in the results. 547HP and 562TQ!!!! Yes 560+ torque out of a MILD streetable SBM setup. Still want more? Ok. Stay tuned, as this combo has even more in it.
 
AndyF said:
You lost me there. The RPM is a tall intake why are you sticking with it if you have hood clearance issues? Have you ever measured a Victor intake?
Click to expand...

I see it is shorter, is the victor superior to the rpm intake in my application ?
 
Mike has put up a few really nice stroker builds that make good torque. I jumped on the "little blue monster" design with the roller Lunati cam. Haven't run it yet.
 
11.2 said:
I see it is shorter, is the victor superior to the rpm intake in my application ?
Click to expand...

Now that is a good question. Typically the RPM intake is the best one to use for a street driven performance car since it provides a lot of bottom end torque and it doesn't give up HP to a single plane until fairly high in the rpm range. (which most street cars never see anyway)

But when you build a big inch stroker motor (more than 420 inches or so) you'll already have so much torque that it might make sense to give away a little bottom end and enjoy the better fuel distribution that you get with the single plane.

Very combination specific. Depends on car weight and gears and cam size etc.
 
My 408 ran 6.57 @ 108 on pump 93 in a 3260# 69 Dart. It was 10.9-1, Hughes flat solid 260/264 @ .050, .628/.633, Curtis Boggs (RFD) ported Edelbrocks and a Victor 340 intake that I port matched with a Biggs 950HP. My converter flashed 5200, 4.10 Dana with 325/60 MT radials.

Don't let anyone fool you, these engines don't need a dual plane intake to make torque down low. Mine pulled anywhere in the rpm range no matter what gear it was in. When I first built it the car had an 8 3/4 with 4.30 gears and 275 MT ET Street radials. After driving for a couple days I wanted to check the flash stall of the converter so I slowed down to 15-20 mph (in high gear) and floored, it immediately blew the tires off. I tried it several times with the same result, 15 mph to 50 mph same result. The trans had a CRT manual valve body so it was in high gear, no kick down.

It seems that the Victor is known for core shift issues so pay close attention to the port alignment.
 
11.2 said:
I've been running a 360/408 for three years now, I always planned on doing the gen III conversion but I've finally faced reality and it will never happen. So I want to upgrade to a steel crank and roller cam, it just so happens a local gentleman Is willing to give me a decent price on my shortblock so I will build a new one and reuse my top end, here's some info
340 virgin block
Ported Eddie heads with port matched rpm intake
Fast ez efi
Msd e curve in conjunction with 6a ignition
518od tranny
3.91 gears

My goal is 550ish hp and trying to stay under 3000 rpm stall and pump gas.
wich stroker kit is the hot ticket these days, scat? Eagle? I've heard about coated Pistons, is there any disadvantages ? Any advise is appreciated including oil pumps, oil pans with best clearance, timing chains.... U name it
Click to expand...

I should have a 4.125 4340 crank available soon from a very respectable source, it will use an I beam rod, dish CP piston and 1.2mm ring stack!
This coupled with some port work on your intake will make at least 550HP....at 10:1.
Brian
 
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