You gave me hope.

What was your fuel setup?
What tuning?

So, I guess I can use T76 with 12 psi for close to 700RWHP. Maybe with race fuel I can up the boost to 14 or 16 psi.

If I use 64cc Trickflow heads, my compression will be 9.35:1 with those -16 dish pistons. Not that much.

 

Aeromotive 1000, -8 fuel lines, 71# HI injectors
HP Tuners 2 bar map.

regarding your other post, cooling is my speciality.

 

blue, there is a lot of experience in this room, all but one telling you 700rwhp is not safe on pump gas at that compresion ratio.

I will be going to the dyno soon with my low compresion 408 and pt88 turbo, i would be thrilled to see 700rwhp with my set up on pump gas.

i dont know about other turbos but this small frame 88 that i have now spools quite a bit slower than the 76 that i had before and i have 408 cubes spining the thing. i would stick with the t76. you can always step up later if you do max out the 76.

 

Parish,

So, I should count 2 for people who support going with 10.25 CR for 700RWHP turbocharging.

I like the way you're doing your own R&D. Keep up the good work.

 

no, sorry i guess i didn't make much sence there.

i am saying with my much lower compresion, more cubes and more efficent turbo i would be happy to see 700rwhp with pump gas. i dont think you have a chance, your compresion is too high.

 

Okay, got your message now.

What was your compression and boost when you where running the T76.

How much boost do you think I can run with my current CR, be it pump gas or race fuel. I keep saying it's not a daily driver.

 

with race gas you wont have any problem maxing that turbo. not sure of your driveline losses but if your running a stick you might hit 800rwhp.

on pump gas i really dont know, too many variables. you might hit 600rwhp on the dyno but put it on the street and i bet you have to back off the boost to keep it from detonating.

a meth kit is cheap and would go a long ways toward your goals. 700+rwhp with meth injection and a t76 might be possiable.

 

my 6.0 was 9.4-1 and the most boost i could run was about 9psi. with the 408 at ~8.8-1 compresion i can get to 11psi before i see knock. i could always run more boost than that on the dyno but not on the street with a real load. dump in race gas and i could crank it all the way up to about 18psi(falling to 16psi) with no knock at all. the turbo was maxed at that point.

i have tried from 10deg timing up to 24deg and varied my fuel from 11-1 up to 12.5. the fueling didn't seem to make much diference on either power or knock. the more timing i ran the more power i made but the sooner i showed knock. i could run 11psi with 14deg of timing or 8psi with 22deg of timing and have about the same power with both tunes on the verge of knock. 14deg with more boost seemed safer so i went with that.

 

Don't forget that Bryan has 427 cubic inches. That helps a little

 

So, it's possible to go for 16 psi boost on 10.25CR with race fuel. This is what I want to hear. Is that correct?

I can live with 8 or 10 psi intercooled if I use pump gas. Is that good enough without detonation?

Do you mean with my current 10.25 CR an pump gas? Need more on this.

 

you should be able to hit over 800rw w/ that t-76 on a 6sp
Not sure about the CR question but since Brians combo works pretty good i dont see why urs wont. Just shoot Wilkerson a PM and get some info from him since he seems to have a pretty impressive pump gas/power setup
jus my .02 cents

 

Good idea.

I want to keep the flow of info into this post eventhough I am communicating with Bryan through the PM.

 

race gas is some bad *** stuff. i think you will be able to max that turbo with race gas even with your high compresion.

8psi with an intercooler at your current compresion would probably work. you will just want to start low and work your boost up till you see/hear it knock.

my limited experience with meth injection sugests it isn't as good as race gas but it is close. i am still playing with my kit and i think i may just need more meth volume.

you may be fixating on a hp or boost number too much. just take this one step at a time and see where it takes you. 8psi is going to FLY and take some geting used to. add some meth or race fuel and start turning it up a little at a time, you are going to find making the power is the easy part. geting the rest of the combo to work for you is going to be the hard(fun) part.

 

i know a t76 can make over 800rwhp but he has a lot of cubes and will not be in that turbo max eficency range once he turns it up. with my stock headed 408 the best i could do is 640rwhp. how well do P+P lt1 heads flow? his motor may flow about the same as mine. i do have huge driveline losses so he will see much better numbers than me but going over 800rwhp my not happen. what are the other guys around here doing with t76's?

 

Any backpressure issues with TO4 flanged T76 on big cubes engine?

 

Here are flow numbers on TPiS's heads that I have.

.100 64/52
.200 135/105
.300 193/142
.400 232/165
.500 251/177
.600 251/188

 

sure, a larger turbo would be better for max power but it will be laggy.

how fast do you want to go with the car? i ran a 10.94@124 in my 5000lb truck with boost only on a t76. a crappy 60' too so there was more in it. that is a ways into the 9's in an f body. if you go bigger the lag will be significant. there are ways to get around that at the track but it wont be as much fun to drive on the street.

another thing to consider if you go with a larger turbo is geting it to fit. a pt88 like i have needs at least a 4" down pipe and the turbo itself is larger. geting that to fit in an fbody would be hard and prety much turn it into a race car only set up.

 

seems like that is prety close to what a stock 6.0 head flows and we are not too far off on displacement. we should be able to make some comparisions.

 

Not sure how fast I should do but I want to crank the HP/TQ and Boost numbers to justify cost of putting the turbo, otherwise, 200-250HP nitrous shot will do the job. That's my reasoning for turbocharging.

I have no problem to put low pistons to knock some compression but would like to explore all my options. If it can be done with 10.25 CR even with race fuel, why not.!

 

Not to offend, but I would think one would have tried before comdeming. At least I can say that I have done it. So are you saying that because I am the only one that has done it, that it isnt possible? Or becuase I am the only one that has done it, its not safe. I would have to go back and look but when I came to the forum and asked, what is the maximum amount of power possible on the GM PCM, 600RWHP was the number. When I asked what was the most power I could make on pump gas, I believe the number was around 650. My example is proof that normal engine building rules do not apply to the LS1 family of motors, which every one is basising their opinon on. Not one person on this forum can make that claim. I did the research, spent the money, got the results. No one on the forum has yet to prove to me that it is unsafe, other than it cant be done. The parts in the engine seem to have something different to say about it. when we took it apart, The Carrillo A-Rods, made for 600HP, the bearings, the rings, nothing showed any signs of detonation. Nothing. So prove to me that it is unsafe or not doable. The only reason that I am stepping down in CR, is I want 1100RWHP on the same pump gas. The higher the CR, the better the thermal efficiency. The better the gas mileage. I did not say that you could run 12:1 and on a 427 with pump gas, I reached the limit with 17PSI on pump gas and somwhere around 20:1 dynamic compression, and the limit was not the pump gas, the limit was the weak *** gasket from cometic.

Are you enjoying paying $4.00+ per gallon for gas. and here is the kicker, with dynamic compression being the real measurement, if 822RWHP on Pump gas with 17 psi of boost is possible, anything south of 700 should be extreamly doable. It is not necessary. At 822RWHP if I was on the bleeding edge, 700RWHP is most certainly obtainable on pump gas with his setup and the tune is right.

One more thing, I do not give a flying F&*( if I did not take it down the strip. I drive it on the street, take it on 8 hour plus road trips and every once in a while get the opprotunity to step on it and I pay less than $2.30 a gallon for gas and get 25 miles to the gallon to boot. CAN YOU SAY THE SAME. My guess is not. So the message I would give to you and the rest of the people who have zero clue, quit talking about stuff you know absolutely nothing about. If you build a motor, making 10:1 CR and throw 17PSI at it you blow it up, then you can tell me Im wrong, but basing your information on what everyone else has said here and over the past 50 years of the small block chevy is weak, and not welcomed. The LS style engines are in a class of their own.