Roller cam and turbo charging

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After talking with my machinist today, I'm gonna go mechanical roller. Custom grind from Comp. I'll put up the specs tomorrow.
 
I'm a little late to the party but I've got the Hughes hydraulic roller. It is a 228 / 228 with 550 lift and 116lsa. I've revved it past 7500rpm, and it purrs as low as 400rpm. I went hydraulic because it is not as hard on the roller lifters. Other than the turbo of course, I think this was the best upgrade I've done to my engine.
 
T56MaxTorq said:
You may wanna call a cam company and get a custom grind. With the larger stroke, a 4" crank tends to "soak up" more duration than if it were installed in a 318. So you'll need a little more duration, maybe In the 220-230 @ .050 range. And a higher LSA is always desired In a turbo setup.
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It seems to be in this range, am I missing something?
 
I am by no means an expert in this area. Could someone explain why this seems "tiny"?
I'm using "J" heads with 2.02s and a little bowl work.
 
I guess it really depends on your goals the cam you picked if its a solid roller seems similar to a truck or rv cam for 400+ cid. A solid lifter cam acts smaller than a similar spec hydraulic cam due to the lash the more lash the more smaller the cam acts. My cam is a hydraulic flat tappet with 226 at .050 and .560 lift, This is going into a 360 the powerband on the cam is up to 5800 rpm will probably make peak power around 5400 to 5600 rpm. You will be running 408 cid and will be running a smaller cam basically. as most solid cams act 5 to 10 deg smaller than simalar hydraulic cam. Comp cams recommended a solid roller 240 240 at .050 on a 114 lc for my 360! that was to get peak power at 6000 to 6200 rpm. You should call howards or bullet. Get more recommendations from more than one company. You really need to know what you are wanting out of your vehicle befor you call so you get the best recommendation.
 
Well to a non-turbo guy like me, thats small. A cam of that "small"224*size, In a normally aspirated(NA) 408, will make a ton of torque. Probably more torque than any street tire will handle.But it will peak early and therefore will be down on power.A NA motor needs RPM to make power. Thats the way the equation works.And to operate and make the big numbers at higher rpms takes a Bigger cam. I would think on a (NA)stroker a cam of 240*plus would be desireable.
But a turbo motor is a totally different animal.This is another time when two hairs too small is better than one hair too big.Listen to the cam guys.If you answered truthfully their questions, then the cam size of 224* will be just right. Certainly, it will be a TyreFryer.
And besides, At the boost levels that you are considering, 224* will make more hp/tq than any of us NA-SBM guys can imagine.
 
^^ this is basically what my builder is telling me. For a street car with a 3:55 gear and relatively low compression, I want the torque down low too give good power early. My understanding is, with the higher cylinder pressure and increased velocity it will help the turbo spool up faster as well. The guy has been building boosted engines for a long time and what he's saying makes sense to me. He was also on the phone with the engineers at Comp for an hour and a half, explaining my exact combo and intentions. I am by no means disregarding what some of you guys are saying, I really appreciate your input. There just seems to be a couple different ways to skin this cat...lol
 
AJ/FormS said:
Well I wouldnt say bazzilion,but yup theres a lotta ways. turbos open up a whole new world.
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You got that right!
This is something I've been wanting to do for a long time. My father says "if you dont...you'll always wonder if you should have"...I just hope I don't end up wishing I hadn't!
Again, I really value all of your opinions and experience and will surely have more questions in the future. I'll try to keep up with updates and progress as I get farther along.
 
RJK3 said:
^^ this is basically what my builder is telling me. For a street car with a 3:55 gear and relatively low compression, I want the torque down low too give good power early. My understanding is, with the higher cylinder pressure and increased velocity it will help the turbo spool up faster as well. The guy has been building boosted engines for a long time and what he's saying makes sense to me. He was also on the phone with the engineers at Comp for an hour and a half, explaining my exact combo and intentions. I am by no means disregarding what some of you guys are saying, I really appreciate your input. There just seems to be a couple different ways to skin this cat...lol
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sounds like a tad misinformed. I will be running 2.73s when I go turbo. Low compression and low gearing won't matter if you are running boost. Call and get cam spec by Bullet, bet you it's WAY different
 
RJK3 said:
224/226 @ .05 .560 lift 114 lsa
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Dont seem to bad for a turbo build of mild setup your running. You want quick cylinder pressure to help spool quicker. Just hope you dont run out of turbine on the upper rpm range.
 
That duration seems really short for a stroker......
 
224 sounds like a pretty decent cam. What a lot of folks don't understand is that high duration numbers with a turbo is sometimes the opposite of what you want. You don't want to hold both valves open nearly as much as a NA motor. You don't really need to use the scavenging effect of the exhaust to help draw in the mix from the intake (like the basic principle of a 2 stroke) The turbo does all the work and forces the mixture into the chamber.
 
turbofreek said:
Dont seem to bad for a turbo build of mild setup your running. You want quick cylinder pressure to help spool quicker. Just hope you dont run out of turbine on the upper rpm range.
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Could you help me out with what diameter header tubing I should use? Also what A/R for a S480 would you recommend for my combo?
 
I also have a 408 small block with a turbo--a T70. Don't ask me how much this cost, because I bought it in 2007 or 2008.
 

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RJK3 said:
Could you help me out with what diameter header tubing I should use? Also what A/R for a S480 would you recommend for my combo?
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Just need the tube large enough not to cover or squeeze the exhaust flow out the head. The turbo will be your biggest restriction in your exhaust. Give you an idea. Banks twin manifold hit for a small chevy is 1 7/8ths logs and have made 1500hp. Most just cant fathum that.

I just say dont go to the big side for primary tubes. Keep the velocity up to help spool. With a 499 inch your not gonna have this issue at all.

S480 has a 96mm turbine wheel and biggest i know is a 1.32ar. Your gonna get extremely quick spool with this on your engine. Gonna be really hard to control power honestly. Consider very large wastegates for sure if your running a single s480.

Id strongly suggest you look into a garret gt budget turbo based of a gt50 frame. Will have a larger 115(?)mm turbine wheel and breath easier on your big cube engine. Will allow better spool control for better power management. Anything like your doing is gonna need power management. Even low levels is gonna be monsterous power.
 
RJK3 said:
224/226 @ .05 .560 lift 114 lsa
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Mine was for 410 Stroker. This engine is in my Scamp in the Avatar as NA & 200Hit of NOS instead of the TT set up.

242@50 , .634 Lift at the valve on a 110-112 LSA if I recall correctly. Solid Roller from Brian at IMM with his Solid Roller Lifters.

FWIW, I drive the **** out of this car everywhere. 100's of miles in single outings. Matter of fact I am leaving today around 3pm.. by the time it is all over tonight I will probably rack up 200+miles , Freeway with 4.30 gears too. I AM the myth buster!
 
turbofreek said:
Just need the tube large enough not to cover or squeeze the exhaust flow out the head. The turbo will be your biggest restriction in your exhaust. Give you an idea. Banks twin manifold hit for a small chevy is 1 7/8ths logs and have made 1500hp. Most just cant fathum that.

I just say dont go to the big side for primary tubes. Keep the velocity up to help spool. With a 499 inch your not gonna have this issue at all.

S480 has a 96mm turbine wheel and biggest i know is a 1.32ar. Your gonna get extremely quick spool with this on your engine. Gonna be really hard to control power honestly. Consider very large wastegates for sure if your running a single s480.

Id strongly suggest you look into a garret gt budget turbo based of a gt50 frame. Will have a larger 115(?)mm turbine wheel and breath easier on your big cube engine. Will allow better spool control for better power management. Anything like your doing is gonna need power management. Even low levels is gonna be monsterous power.
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Thanks for the info!
I'll look into the Garrett.
 
i too have been looking into the roller cam thing. have been offered a set of new unused Lunati solid roller lifters. are these a good lifter? mine is a 410 with s475 efi.
 
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