365" or 403" LS2 with T-Trim?
#1
365" or 403" LS2 with T-Trim?
Hey Guys, I've been talking with Leo at Weber and I'm ordering up one of their LS2 shortblocks for my F-body.
At first I decided to go with a 365ci, stock crank, 4.005" bore, -11cc pistons. Now I'm having second thoughts and think a better choice may be a 403ci, forged 4" crank, 4.005" bore, -15cc pistons.
My car is 95% street car. I'm going to run a Vortech T-Trim with a 2.75" pulley, and 8.00" crank pulley, so it'll be maxed out. The blower will supposedly support 825fwhp/1200cfm. I've seen good numbers with the T-Trim, of Late, "Navy" making 730rwhp.
So, my question is about longevity of the engine. With the blower, both engines should be capable of making the same power, with the 403 probably making a little more power under the curve, with less boost.
Would there be a benefit of running the 403 at say ~10-12psi vs. the 365 at 14-16psi? The boost numbers don't matter to me, so If I can have a 403 making the same power with less boost, wouldn't that be the way to go for reliability and longevity?
You Procharger guys are more than welcome to give me some insight too.
Thanks in advance
At first I decided to go with a 365ci, stock crank, 4.005" bore, -11cc pistons. Now I'm having second thoughts and think a better choice may be a 403ci, forged 4" crank, 4.005" bore, -15cc pistons.
My car is 95% street car. I'm going to run a Vortech T-Trim with a 2.75" pulley, and 8.00" crank pulley, so it'll be maxed out. The blower will supposedly support 825fwhp/1200cfm. I've seen good numbers with the T-Trim, of Late, "Navy" making 730rwhp.
So, my question is about longevity of the engine. With the blower, both engines should be capable of making the same power, with the 403 probably making a little more power under the curve, with less boost.
Would there be a benefit of running the 403 at say ~10-12psi vs. the 365 at 14-16psi? The boost numbers don't matter to me, so If I can have a 403 making the same power with less boost, wouldn't that be the way to go for reliability and longevity?
You Procharger guys are more than welcome to give me some insight too.
Thanks in advance
#6
Not sure off the top of my head, but it's rated for 55,000rpm. Overspinning it a little won't hurt it. Heck, guys on here have been doing it for a while now. Although, the 2.75" pulley is the smallest RMCR recommends.
Anyway, back to the original question...
Anyway, back to the original question...
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#8
Hey Guys, I've been talking with Leo at Weber and I'm ordering up one of their LS2 shortblocks for my F-body.
At first I decided to go with a 365ci, stock crank, 4.005" bore, -11cc pistons. Now I'm having second thoughts and think a better choice may be a 403ci, forged 4" crank, 4.005" bore, -15cc pistons.
My car is 95% street car. I'm going to run a Vortech T-Trim with a 2.75" pulley, and 8.00" crank pulley, so it'll be maxed out. The blower will supposedly support 825fwhp/1200cfm. I've seen good numbers with the T-Trim, of Late, "Navy" making 730rwhp.
So, my question is about longevity of the engine. With the blower, both engines should be capable of making the same power, with the 403 probably making a little more power under the curve, with less boost.
Would there be a benefit of running the 403 at say ~10-12psi vs. the 365 at 14-16psi? The boost numbers don't matter to me, so If I can have a 403 making the same power with less boost, wouldn't that be the way to go for reliability and longevity?
You Procharger guys are more than welcome to give me some insight too.
Thanks in advance
At first I decided to go with a 365ci, stock crank, 4.005" bore, -11cc pistons. Now I'm having second thoughts and think a better choice may be a 403ci, forged 4" crank, 4.005" bore, -15cc pistons.
My car is 95% street car. I'm going to run a Vortech T-Trim with a 2.75" pulley, and 8.00" crank pulley, so it'll be maxed out. The blower will supposedly support 825fwhp/1200cfm. I've seen good numbers with the T-Trim, of Late, "Navy" making 730rwhp.
So, my question is about longevity of the engine. With the blower, both engines should be capable of making the same power, with the 403 probably making a little more power under the curve, with less boost.
Would there be a benefit of running the 403 at say ~10-12psi vs. the 365 at 14-16psi? The boost numbers don't matter to me, so If I can have a 403 making the same power with less boost, wouldn't that be the way to go for reliability and longevity?
You Procharger guys are more than welcome to give me some insight too.
Thanks in advance
#10
I currently still have the G-Trim on the car, and have been collecting parts, ie: T-Trim, fuel system, suspension, rear end, etc. The engine is pretty much one of the last things I need to buy.
The more research I do makes me lean toward the 403 now.
#14
#15
Thanks for the replies everyone. I think you've helped me make my decision to go with the 403. I'll call Leo at Weber in the morning to discuss it.
Mr.Big, that really is a great price on Mr.MartySone's engine. It even comes with head studs which run another couple hundred dollars! In my original post I mentioned -15cc pistons, but when I looked into it a little more I realized -20cc would net around 9.7:1 compression with a 65cc combustion chamber, which is where I want to be. Like I said before, If I hadn't already made arrangements with Weber Racing, I probably would have bought this engine.
Mr.Big, that really is a great price on Mr.MartySone's engine. It even comes with head studs which run another couple hundred dollars! In my original post I mentioned -15cc pistons, but when I looked into it a little more I realized -20cc would net around 9.7:1 compression with a 65cc combustion chamber, which is where I want to be. Like I said before, If I hadn't already made arrangements with Weber Racing, I probably would have bought this engine.
#16
Are you getting the noisier T-trim (the V-1) or the Superquiet V-2 version? The internal stepup is a little different - V-1's are 3.4:1 and the V-2's are 3.61:1. All the T-trims have a rated redline of 55,000rpm.
I like your choice of the bigger motor. That will be a great combo.
Jim
I like your choice of the bigger motor. That will be a great combo.
Jim
#18
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I would do some research....years ago i read hear on the forums that it you run a supercharger that its better to not run that much stroke. that is why i am looking to go with the 365 or 370 vs a 402 with my procharger d1. i will try to find the link for you..