Critique my engine

Steven Rupp · Jun 27, 2007

Ok, looking for opinions on my engine combo. I don't have a ton of blue-oval experience so I thought I would ask the experts.

351W core block, early (around '70)
Stroked to 408 cui.
Eagle cast crank
Eagle forged rods
SPR forged pistons -19cc dish
AFR 205 heads - 55 cc’s gets 10.9:1 CR with zero deck and an .040 gasket
COMP Camshaft, Hydraulic Roller Tappet, 236/240 (.050), Lift .555/ .576, 110 LSA
COMP aluminum roller rockers 1.6 ration 7/16 stud (PN 1044-16)
COMP hydraulic roller lifters (PN 815-16)
COMP early double roller timing chain (PN 2135)
Edelbrock Performer RPM Air Gap
Holley 750 CFM (moved down from 950)
Mallory Unilite vac-advance disty with VI-AL Hyfire box
Milodon pan, windage tray and pickup
Milodon alum water pump
Melling oil pump, ARP oil pump rod
Clevite bearings
ARP bolts - all including dress up bolts
1 3/4 inch FPA headers
Holley fuel pump & regulator

and an as yet to be determined quality dampner.

Thoughts, comments, opinions?

I need to plug all of this into my desktop dyno sim..

blown65 · Jun 27, 2007

I dont believe you would need that much carb on that engine. From the cam specs and intake I'm just guessing but rpm range would be maxed around 6k-6500. Also, for the few bucks more I'd prob go for the steel crank instead of a cast one. Seems like you have alot of good parts to cut that one corner IMO. (At least if you wanna step up in power/rpm you would have a better crank to do it)

Steven Rupp · Jun 27, 2007

blown65 said:
I dont believe you would need that much carb on that engine. From the cam specs I'm just guessing but rpm range would be maxed around 6k-6500. Also, for the few bucks more I'd prob go for the steel crank instead of a cast one. Seems like you have alot of good parts to cut that one corner IMO. (At least if you wanna step up in power/rpm you would have a better crank to do it)

I agree on the crank but I was told to use a cast crank.. I thought the carb seemed a bit big, but with tuning it should be fine. Better to tune down a larger carb than tune up a smaller one.

Yea, I wouldn't spin this thing past 6500.. dyno sim says peak power is at 5500 and peak torque is at 4500.

blown65 · Jun 27, 2007

Steven Rupp said:
I agree on the crank but I was told to use a cast crank.. I thought the carb seemed a bit big, but with tuning it should be fine. Better to tune down a larger carb than tune up a smaller one.

Yea, I wouldn't spin this thing past 6500.. dyno sim says peak power is at 5500 and peak torque is at 4500.

Well, its one thing to tune to the large carb but it does hurt HP some. Maybe not a large number but still. I'd probably do a 850 at most and more likely Id do a 750.

I still would lean towards the steel crank.

Steven Rupp · Jun 27, 2007

blown65 said:
Well, its one thing to tune to the large carb but it does hurt HP some. Maybe not a large number but still. I'd probably do a 850 at most and more likely Id do a 750.

I still would lean towards the steel crank.

Hell, I'm just happy I can run forged rods and pistons.. lol.. my first assignment was to use all cast stuff and hyper pistons. I talked my way out of that.

DynoSim (if you believe what it says) says that power goes up a tad with the 950 over a 850. That doesn't mean it's true in real life.

bnickel · Jun 27, 2007

i think you'll be fine with the cast crank and 950 carb. with a power peak of 5500, which is just about right for a stroker windsor, a cast crank is as tough as you'll ever need. now if it were a smaller crank like a 302 or 350 chev i'd think seriously about using a steel crank. the windsor crank has such large mains if you were going over 6500 rpm you'd really need to go to a smaller journal cleveland style crank anyway.

Steven Rupp · Jun 27, 2007

bnickel said:
i think you'll be fine with the cast crank and 950 carb. with a power peak of 5500, which is just about right for a stroker windsor, a cast crank is as tough as you'll ever need. now if it were a smaller crank like a 302 or 350 chev i'd think seriously about using a steel crank. the windsor crank has such large mains if you were going over 6500 rpm you'd really need to go to a smaller journal cleveland style crank anyway.

DynoSim has peak hp at 584 at 6000 RPM and 586 ft-lbs at 4500 RPM.. No need to ever spin it past 6500.. I will most likely rev limit it around 6300 to be safe.

That's with the exact flow numbers from the ported out AFR heads. Oh and it's flywheel power thought mufflers. I'm not totally sold on dyno software yet, but it at least gives you an idea.

I think it's a bit optimistic. I would be happy if it comes in near 500/500 (hence the project name.. Fastlane 500.. get it? lol)

SoCalCruising · Jun 27, 2007

Use the Crane optical dizzy. You won't regret it.

Nobody listens to me on this, but I use the Jacobs 2000 "box" and their coil. It's a nice setup and plugs right in.

You do need a decent damper, esp. with the cast crank (low ductility). The Summit SFI balancer should be fine.

I really like those cams specs for that motor, I just don't like reduced base circle cams; too much flex in 'em.

I don't think you'll need that much carb. Even if you get a little more power up top, I'd think that your average hp might be less and throttle response would not be as good. I read about a guy put on a 575 Demon on a 393 bracket motor and was shocked how much he liked it. I think he was down a 1/10 or something, but commented on the responsiveness of the motor and what a great street carb it would be. A Holley 750 HP should be enough, really. Who needs a choke in SoCal, anyway?

I'd try for a little less compression if you want to use pump gas and all the ignition timing that motor can use. I wouldn't think that your cam is so big as to bleed off enough compression to run that much static compression, but maybe someone else can comment on that, too.

Steven Rupp · Jun 27, 2007

SoCalCruising said:
Use the Crane optical dizzy. You won't regret it.

Nobody listens to me on this, but I use the Jacobs 2000 "box" and their coil. It's a nice setup and plugs right in.

You do need a decent damper, esp. with the cast crank (low ductility). The Summit SFI balancer should be fine.

I really like those cams specs for that motor, I just don't like reduced base circle cams; too much flex in 'em.

I don't think you'll need that much carb. Even if you get a little more power up top, I'd think that your average hp might be less and throttle response would not be as good. I read about a guy put on a 575 Demon on a 393 bracket motor and was shocked how much he liked it. I think he was down a 1/10 or something, but commented on the responsiveness of the motor and what a great street carb it would be. A Holley 750 HP should be enough, really. Who needs a choke in SoCal, anyway?

I'd try for a little less compression if you want to use pump gas and all the ignition timing that motor can use. I wouldn't think that your cam is so big as to bleed off enough compression to run that much static compression, but maybe someone else can comment on that, too.

Thanks, all good points.. I'm going to pick some brains tomorrow regarding the carb choice. That was also my worst case senario on the compression. I need to pencil it out exactly.

55cc head
-19cc dished piston
.040 gasket
4.030 bore

hmmm...

Yea, for the dampner I'm looking at TCI, ATI or Professional Products (their SFI unit). I've heard that the 351w cranks need a good dampner.

Steven Rupp · Jun 27, 2007

SoCalCruising said:
Use the Crane optical dizzy. You won't regret it.

Nobody listens to me on this, but I use the Jacobs 2000 "box" and their coil. It's a nice setup and plugs right in.
.

Oh, I'm commited to the Mallory stuff.. will see how well it works out

blown65 · Jun 27, 2007

SoCalCruising said:
Use the Crane optical dizzy. You won't regret it.

Nobody listens to me on this, but I use the Jacobs 2000 "box" and their coil. It's a nice setup and plugs right in.

You do need a decent damper, esp. with the cast crank (low ductility). The Summit SFI balancer should be fine.

I really like those cams specs for that motor, I just don't like reduced base circle cams; too much flex in 'em.

I don't think you'll need that much carb. Even if you get a little more power up top, I'd think that your average hp might be less and throttle response would not be as good. I read about a guy put on a 575 Demon on a 393 bracket motor and was shocked how much he liked it. I think he was down a 1/10 or something, but commented on the responsiveness of the motor and what a great street carb it would be. A Holley 750 HP should be enough, really. Who needs a choke in SoCal, anyway?

I'd try for a little less compression if you want to use pump gas and all the ignition timing that motor can use. I wouldn't think that your cam is so big as to bleed off enough compression to run that much static compression, but maybe someone else can comment on that, too.

I agree 100%. It would be different if it was for drag racing but thats not what the motor specs are. Its a mild street 408 and a 950 is too big. (with a dual plane intake on top of it.) If you were going VictJr and a 950 then maybe it would make a little more sense I guess.

I think his compression will be ok. We have a 347 with very close to the same compression and actually a tad bigger cam (112 c) and it runs great on 92 pump gas. Just keep the timing in check and you'll be ok. Alum heads help with that also.

Steven Rupp · Jun 27, 2007

blown65 said:
I agree 100%. It would be different if it was for drag racing but thats not what the motor specs are. Its a mild street 408 and a 950 is too big. (with a dual plane intake on top of it.) If you were going VictJr and a 950 then maybe it would make a little more sense I guess.

I think his compression will be ok. We have a 347 with very close to the same compression and actually a tad bigger cam (112 c) and it runs great on 92 pump gas. Just keep the timing in check and you'll be ok. Alum heads help with that also.

You know.. now that I think of it that cam was obtained back when this was a going to be a solid roller motor with the AFR 225 heads.. lol.. guess I forgot to revisit the issue.

The car will be drag raced.. should do good with it's load out of stuff.

3460 lbs (sans driver)
Hughes C4 trans, 2800 stall
Strange 9-inch, posi, 3.70 gears

Compression should be fine with the right timing... I agree on the carb.

You really catagorize that motor as "mild".. I see it more in the medium range. I know that cam won't be as lopey in the 408 as it would be in a 351 but it should still shake things up a bit. I really didn't see a hugh gain in the sim software by going bigger on the cam (240/246 112LSA). ramp speed seemed to make the biggest difference. Even switching to a single plane Vic Jr didn't do a ton.. just dropped the TQ and raised the HP. Personally I'd rather have TQ in a street car.

fvike · Jun 27, 2007

I'd like to see the Crane optical distributor get some spotlight too. I got it, and love it!

For damper: Damper tech tread on Corner-Carvers. Looks like ATI got their vote.

Steven Rupp · Jun 27, 2007

fvike said:
I'd like to see the Crane optical distributor get some spotlight too. I got it, and love it!

For damper: Damper tech tread on Corner-Carvers. Looks like ATI got their vote.

Yea, the ATI stuff rocks.. I'm running on my LS2 engine. Expensive though (so is the TCI Rattler).. gotta find that sweet spot between price and function.

fvike · Jun 27, 2007

Steven Rupp said:
Yea, the ATI stuff rocks.. I'm running on my LS2 engine. Expensive though (so is the TCI Rattler).. gotta find that sweet spot between price and function.

Ford Racing got both cheap and expencive dampers over at Summit.

69gmachine · Jun 27, 2007

good combo

I have a very similar combination (see sig) and the 735 vacuum secondary Holley is more than enough for it. As mentioned by SoCAl and blown65, you will be trading a few ponies at the very peak of your RPM limit for a large area under the curve from idle all the way to 5K. Look at the total area under the curve, and look where the curve is fattest. Make sure you're goiong to actually use that hi PM power.

Everything else looks like it will work together fine. I wouldn't lose one minute of sleep over the cast crank, especiallly if you use a rev limiter. You didn't mention whether you intend to run a manual or automatic. If you go stick, I'd use an aluminum flywheel. It'll make that 408 rev like a 302. If the cam is on a reduced base circle, you really have to watch the RPMs, but you should be fine if you keep it under 6K. I now have an off the shelf Comp XE-282 Hyd roller. I also used their new link bar roller lifters. I would suggest to anyone who puts aluminum heads on an iron block to use MLS head gaskets. I used Cometic because they developed them, but several vendors offer them now.

After I finished putting my engine back together (bent 6 intake pushrods at Barber Motorsports Park last year) with an entirely new valvetrain, I took it to a local Ford engine builder who does drag, dirt, and circle track engines. He told me that the most likely culprit was that my valves were over tightened, and probably didn't have the right geometry. He's checking everything over before i put it back in the car.

Steven Rupp · Jun 27, 2007

69gmachine said:
I have a very similar combination (see sig) and the 735 vacuum secondary Holley is more than enough for it. As mentioned by SoCAl and blown65, you will be trading a few ponies at the very peak of your RPM limit for a large area under the curve from idle all the way to 5K. Look at the total area under the curve, and look where the curve is fattest. Make sure you're goiong to actually use that hi PM power.

Everything else looks like it will work together fine. I wouldn't lose one minute of sleep over the cast crank, especiallly if you use a rev limiter. You didn't mention whether you intend to run a manual or automatic. If you go stick, I'd use an aluminum flywheel. It'll make that 408 rev like a 302. If the cam is on a reduced base circle, you really have to watch the RPMs, but you should be fine if you keep it under 6K. I now have an off the shelf Comp XE-282 Hyd roller. I also used their new link bar roller lifters. I would suggest to anyone who puts aluminum heads on an iron block to use MLS head gaskets. I used Cometic because they developed them, but several vendors offer them now.

After I finished putting my engine back together (bent 6 intake pushrods at Barber Motorsports Park last year) with an entirely new valvetrain, I took it to a local Ford engine builder who does drag, dirt, and circle track engines. He told me that the most likely culprit was that my valves were over tightened, and probably didn't have the right geometry. He's checking everything over before i put it back in the car.

Thanks, I'm running a Hughes C4 with a 2800 stall.

blown65 · Jun 27, 2007

I'm not worried about the cast crank either, but I'm one to buy for future. I dont know what the future plans are so thats the reason for pointing towards a steel crank. Nothing is more frustrating than after doing a build and finding out, man I wish I had more and now its going to cost 2x as much cause I gotta buy better parts.

As for the mild comment. I think its going to be a good runner, def not stock. To me its mild though. hehe I more or less meant it should be a good low rpm torqy motor with that combo (again, back to the smaller car. )

Medium to me is what we built up in our Pantera. 12-1 comp, Solid roller, 7k rpm peak, AFR205's.

Anyhow, sounds like fun, but even though you say your going to drag it, its not a drag race sort of setup IMO. Its a street/strip and I think the little in ET you will lose cause of a smaller carb (if any loss) you will gain in off throttle response and midrange. I'd almost bet that average HP will be more over the entire power band with the smaller carb.

Steven Rupp · Jun 27, 2007

blown65 said:
Medium to me is what we built up in our Pantera. 12-1 comp, Solid roller, 7k rpm peak, AFR205's.

Anyhow, sounds like fun, but even though you say your going to drag it, its not a drag race sort of setup IMO. Its a street/strip and I think the little in ET you will lose cause of a smaller carb (if any loss) you will gain in off throttle response and midrange. I'd almost bet that average HP will be more over the entire power band with the smaller carb.

lol.. 12:1 solid roller is medium?

yea, the whole goal was to build a fun street/strip car that you could cruise around or take to the track. and that looks nice as well. I'm hoping for low 12's and maybe high 11's if I'm lucky (on drag radials).

Will have around $26k into the car when done. Not bad for nice paint, interior and all the mechanics brand new.

D.Hearne · Jun 27, 2007

Keep the cast crank and go for a smaller carb. A smaller will be easier to tune than one that's too big. Or go with dual fours. With two 450 Holleys. www.pricemotorsport.com

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