Goal is 8s with a six speed (built if necessary, and it probably will be) with 20 or so psi and race gas. high 9s on pump gas. Will be in a 3400 or so raceweight SS with whatever gears I decide to run in the moser 12 bolt (has a solid pinion spacer and spool with 33 spline axles). I will be running a BS3 I think as well.

I am having a 408 built at ape right now with a callies crank, callies pro I beam rods, and diamond pistons as well as all the little stuff. The motor will be about 8.5 to 1 with 72 cc heads. First off, do you think the heads really make that much difference in hp as far as their flow capability. It doesn't seem that most here think so. The reason I ask is that I want to be able to run 20 or more psi and like the thickness of the decks of the AFR's. I was thinking of just getting some as cast AFR's and having a local guy do some minor porting as well as a valve job and maybe a large exhaust valve.

Second, I think a single T88 is the best option and most cost effective. What do you guys think. The big motor shouldn't have a problem spooling this up I think. The only thing that will be hard is to get the large 5" or so down pipe out into the back of the car. I saw the speed inc setup which uses a 5" knecked down to a 4". Is it possible to split it into a y and run two 3.5 pipes with borla xr-1 sportsman mufflers?

Third, what intake for this kind of power. Lingenfelter runs the ls6 and has gone 8s. Should I just go back this route? Mine is ported and I will be selling it only because I think it is too thin to run 20+/- pounds on it.

Fourth, what fule setup are you big boost guys running? What injectors? What fuel rails? What sized fuel lines? I can control a low impedence injector with the BS3 I think so that should open up some oppurtunity.

Fifth, what style cams do you guys like? would a tight lsa cam work well for a turbo because it bleeds off cylinder pressure into the exhaust and spins the turbo even harder or will I loose too much cylinder pressure to be effective. It seems the single pattern cams are very popular with the turbos.

Any suggestions will be greatly appreciated. I am looking forward to getting started with this project. I'm sure I'll have many question for you guys down the road. Thanks.

 

BigStuff3 will drive high or low impedence injectors.

 

Well with that weight you are going to need a bigger turbo. 94mm should do, as your going to need alot more power for the 6speed.

i dont know how you would Y the exhaust into 3.5" pipes, you will probably be getting a motorplate where you can pass a 4" pipe by the engine to the back, or you could just dump a big 5" exhaust out the front bumper. there wont be enough room on the driverside for a big exhaust pipe.

injectors you'll probably need some 160's and one or two big external pumps. 10 an line, billet fuel rails.

ls6 intake willl work, or you could do a sheetmetel, or single plane

id go with some good AFR heads, youll need everybit you can get.

 

Ur gonna need to run a lot more than 20lbs of boost. Chad William's viper was running more than that with a 488cid v10 and ported heads when he went 8.75. With a six speed you will need to make up for all the boost lost between shifts by making more when you are actually in gear. Obviously it is not optimal.

 

Thanks for the input man. A t94 hugh, that sounds like a monster. Do you think it will spool up below 4000rpm? I am shooting for high high 8s with this setup. Man, those are some big injectors.

 

What kind of boost were they seeing on that motor?

 

I am having a 408 built at ape right now with a callies crank, callies pro I beam rods, and diamond pistons as well as all the little stuff. The motor will be about 8.5 to 1 with 72 cc heads. First off, do you think the heads really make that much difference in hp as far as their flow capability. It doesn't seem that most here think so. The reason I ask is that I want to be able to run 20 or more psi and like the thickness of the decks of the AFR's. I was thinking of just getting some as cast AFR's and having a local guy do some minor porting as well as a valve job and maybe a large exhaust valve.
---AFR 225 castings sound good to me.



Second, I think a single T88 is the best option and most cost effective. What do you guys think. The big motor shouldn't have a problem spooling this up I think. The only thing that will be hard is to get the large 5" or so down pipe out into the back of the car. I saw the speed inc setup which uses a 5" knecked down to a 4". Is it possible to split it into a y and run two 3.5 pipes with borla xr-1 sportsman mufflers?
---no idea


Third, what intake for this kind of power. Lingenfelter runs the ls6 and has gone 8s. Should I just go back this route? Mine is ported and I will be selling it only because I think it is too thin to run 20+/- pounds on it.
---OH Boys have made big power with LS6 intake.


Fourth, what fule setup are you big boost guys running? What injectors? What fuel rails? What sized fuel lines? I can control a low impedence injector with the BS3 I think so that should open up some oppurtunity.
---2 Bosche 420L fuel pumps, Speed Inc drag tank, 83 lb Siemens, BS3, -10 to the front, -8 crossover, -6 return, Weldon regulator, C16 fuel


Fifth, what style cams do you guys like? would a tight lsa cam work well for a turbo because it bleeds off cylinder pressure into the exhaust and spins the turbo even harder or will I loose too much cylinder pressure to be effective. It seems the single pattern cams are very popular with the turbos.
---Get with Kurt from W2W to pick a cam.

 

I dont know an exact number, as they were kind of secretive on all those issues. But I can probably talk to Chad and find out. They are increasing the boost and putting in a glide for 7's this year. I will try to find out exactly how much air is actually being pumped in per minute and see what that comes out to.

 

Thanks man, if ya find out let me know, if not no biggy.

 

Thanks John. Weel to weel keeps comming up in f/i. I will give them a call. Thanks again.

 

ya W2W does good work

i dont think 83's will support an 8 second time slip with a stick at that weight, your going to need to move up to 160s or multipul injectors, which bs3 can support

 

I think Siemens 83's with the base fuel pressure around 50psi could be okay.

 

where are you going to fit a turbo like that? keeping stock radiator position? what about power steering or a/c? high mount alternator?

what is your header configuration going to be?

would take 1100rwhp or so i guess??

 

I happen to know the answers to all these questions, I'm finishing up one right now. The goal for said car is only 9's with maybe a high 8 for fun. You can use this formula to get you close on the fuel side. Crank HP (you'll need about 1000-1100 at full weight) x .5 , divide # of cylinders x 11 = you needed injector size. Remember most injectors are not rated at our fuel pressure and you'll probably run more anyways.

I personally would us a GT42R (BB) or maybe the new 55. Header size is pretty much limited to 1 3/4 due to space limitations. 4" exhaust is the limit you can fit under the car. You could run a 5" dump but that wouldn't be very streetable. If you needed more volume I'd split the 5" to duel 3 1/2" out the back.

 

I would like to see someone do large twins (76's maybe) with accessories, a mn6, and 16 injectors...8 for 93, 8 for 110-116.

I'm just thinking out of my *** right now, but what about positioning the turbo's like the QMP does...but with one on the other side too. Or like the TTi Race Kit...same config. OR...like the phamspeed does x 2. Inlets facing each other, run the DP's through the fenders or something...I dunno. OR maybe some HUGE GN-style hybrids (70mm compressors - at least) mounted low like that. I think getting the exhaust out would be easier, but the wastegates and discharges would be harder. Who knows.

here's the moral of that rant. Just do something...don't wait for any of us to give you a magic formula. Talk to the pro's (majestic turbo, ptk, forcedinductions, etc.)...especially 5.0 builders and pic a hp goal, then turbo's, then a motor, etc, etc.

 

I started a post a while back about the 42R dual BB and Harlan said t was to small to get 800 rwhp...... at least for my 370 so i doubt his 408 will be any better................ do a search for the thread.... thats why i going with a T-88... but my goals are not 8's.... hell there not even 9's right now..............
Kyle

 

It will be a similar setup to speed Inc's. No a/c, no power steering, re-mount the a/c. I was thinking somewhere close to where the a/c pump would normally be. The car will going up to the shop I tune for this week and will be getting measurements.

 

I don't see my 408 being any better on anything except allowing the turbo to spool faster, 4" stroke probably moves a lot of exhaust.

Here is the pics of the speed inc setup. Do you think necking down to 4" will hurt power potential. Do you think it would be better to take the 5" and y-pipe it to two 3.5" pipes. I don't rely like the idea of having a 5" pipe dump at the front of the motor, too many fumes and too much heat.

https://ls1tech.com/forums/showthrea...&highlight=T88

Also, if you go to the sixth page of the thread you can see the system in the car.

 

The GT42R-76 will make 800rwhp on a 370 LS1. Its nothing more then a 76GTS with a BB CHRA.

Jose

 

I don't think that will be enough for my needs. Looks to me like 1000rwhp is where I need to be with this car.