346 or bigger for a procharger?
11-26-2006, 09:14 AM
#41
Originally Posted by ty_ty13
i think since you are a a4 car your gains would not be significant.... because it keeps your rpms up so the lower rpms are not used.... but if you were a stick car with 3.5 gears id say youd see again because of the more torqued you'd have below 4.5k rpms
but yes, its not going to affect PEAK cfm because the blower will only push so much... but a bigger motor i think will effect how soon it sees that peak cfm....
this is only theory because i have never swapped out motor combos on the exact same blower...
but id also say you might also see a slight decrease in IAT's
but yes, its not going to affect PEAK cfm because the blower will only push so much... but a bigger motor i think will effect how soon it sees that peak cfm....
this is only theory because i have never swapped out motor combos on the exact same blower...
but id also say you might also see a slight decrease in IAT's
May or may not see a difference in IAT, the blower has to work slightly harder with more backpressure, but a bigger cam/heads/exh in a 346 will also decrease boost and not lose HP - to a point anyhow. An M6 car doesnt have a huge drop between gears and the RPM stays up there pretty good too, getting the car to 60 foot is a different matter though. I'll take a 346 and proper converter over a 408 and a M6 any day if ETs are my goal. Under 4500rpm really isnt a concern for most people, except taking off from a stoplight under no boost but its not like a 346 is weak little n/a engine.
As far as the L92 heads I think by the time you buy everything to do it you are probably better off just buying a set of decent aftermarket heads and bolting them on if you already have an LS6 intake on a forced induction engine.
With these engines 4" cranks get you a lot of piston speed, side loading and a lot of crankcase pressure in an already too small crankcase plus going to an LS2 block takes a few extra parts. Iron blocks add 100lbs plus are missing a mounting hole for the procharger bracket. Sure I'd rather have a nice 402 at this point, but to some that extra 1000.00 for the crank + 500 for LS2 conversion parts may be the difference between a better fuel system or good rear end.
Everything is a trade off between money and pita factor. You can reason your way up to 632 inch BBC with twin T88s if you want - it fits
11-26-2006, 10:16 AM
#42
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There is an old saying in racing, cubic inches or cubic dollars. FI changes that to some degree, but I think it still holds true. HP is not everything, you need to think about TQ too. But it's all about the total setup. You can build either to get 700rwhp & tq.
The major difference is where yu make the power. A 402 will make it's HP sooner, and make more TQ. A 346 will have to spin higher, and should make more HP beause of that. More TQ will get you better 60's, more HP will get you more mph. But either combo can get you there.
Case in point - I have a 402 with a D, a friend of mine has a 370 with a T-76, another has a 383 spinner with a 250 shot. We are all making very close to the same HP & TQ. They run 10.0s, I run 10.4s, but my setup still has a couple issues to work out, theirs are close to perfect. So in the end we should all be neck & neck.
There is no wrong choice IMO! As long as you complete the setup you'll be fine.
Oh, and the reasons I went with an iron 402 are I don't like sleeved motors with boost, and it cost me about the same $ to buy a new short block form Scoggin Dickey as it would have cost to re-do my bottom end.
The major difference is where yu make the power. A 402 will make it's HP sooner, and make more TQ. A 346 will have to spin higher, and should make more HP beause of that. More TQ will get you better 60's, more HP will get you more mph. But either combo can get you there.
Case in point - I have a 402 with a D, a friend of mine has a 370 with a T-76, another has a 383 spinner with a 250 shot. We are all making very close to the same HP & TQ. They run 10.0s, I run 10.4s, but my setup still has a couple issues to work out, theirs are close to perfect. So in the end we should all be neck & neck.
There is no wrong choice IMO! As long as you complete the setup you'll be fine.
Oh, and the reasons I went with an iron 402 are I don't like sleeved motors with boost, and it cost me about the same $ to buy a new short block form Scoggin Dickey as it would have cost to re-do my bottom end.
11-26-2006, 07:21 PM
#44
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He didn't make a whole lot of sense their. I see what he is saying in that a stroker motor is harder to spin at a higher rpm but that's really a non issue here in LSX's. They only time I would say not to over rev one of these motors is if it has a stroke bigger then a 4'' which not to many people run.
11-27-2006, 04:58 PM
#46
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my goal is a bad *** street setup with as much torque as i can get. maybe a couple of track passes to see how long before i get kicked out!
but really a nice street rod with some bragging rights. maybe 650rwhp with as much torque as it can muster.
but really a nice street rod with some bragging rights. maybe 650rwhp with as much torque as it can muster.
11-27-2006, 07:50 PM
#48
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if you want mad torque get a big block and call it day like kp said.
go with as much cubes as you can. if the dart block ever comes out , you can get a 454 out of it. then add boost and that would be nice street motor.
but keeping stock cubes and overcoming it with a big blower is cheaper and easier to do.
go with as much cubes as you can. if the dart block ever comes out , you can get a 454 out of it. then add boost and that would be nice street motor.
but keeping stock cubes and overcoming it with a big blower is cheaper and easier to do.
11-29-2006, 05:09 AM
#49
A 346 with a D-1SC can make you over 700 rwhp, enough power to scare the crap out of you until you're use to it... With a chassis set-up for the dragstrip, this kind of power can get you into the nines in the 1/4. Bob
