twin turbo 350

[big reazon]

I own a grand national that is pretty much stock probally going to leave it that way for a while though until I can afford to put the best in it. Here my problem. I drove a mone carlo ls as a daily driver. That I want to start racing sort of. So this is what I did. I got two turbos from 2 2003 duramax diesels. I brought it to a local gn buddy of mine and he ordered springs for the wastegates to get the psi down to about 10 to 12 psi total. The rest of my set up will be a chevy 350 two bolt main with spayed billet main caps.Going to hhave a forged eagle bottom end All clevite bearings. A set of afr210's. Twin intercoolers. Also maybe an xe 274 cam. I also plan on ordering a msd pro e curve distributor with a 6bl msd box. I plan on using a demon blow through carb havent figuredout what size. This is a mostly street driven car. The suspensipn and the rest of the drive train is being handled. going to use a pypes exaust which is a x pipe exaust and maybe even have cut outs added. Expecting about 8:1 compression ratio. But how much hp and torque can I expect from this setup. Also do you have any sugestions. Only reason using modded diesel turbos is because they came free. Buddy used to work at wrekking yard. All I paid for was getting the waste gates modded. But What can i really expect with this setup in number. Suggestions are welcome also.

 

[Dusty Bradford]

Couldn't tell you. I don't know of anyone using the d'max turbo's. Try it and let us know

 

[TURBOPOWERED68]

try and look at what other SBC guys are doing with 10-12 psi that should help.

 

[SGRIM]

Well you have to remember 10psi from one turbo isn't going to be the same 10psi from a different, larger or smaller, turbo.

Good luck with your project though, please post numbers as you get them that is a very interesting setup. I have often wondered how far a 2bolt SBC can be pushed!

 

[John Wilde]

Can you give us any numbers off of the turbo?
Do you know what year that the turbo application is from?
We should be able to get the hp rating once we know what turbos they are.

 

[1dmbth]

03' duramax LB7 Turbo Specs.
Manufactuer IHI (Water Cooled)

Compressor
Inducer 59.9mm (inlet)
Exducer 82.0 mm (max diameter)

Exhaust turbine
Inducer 68.0mm (max diameter)
Exducer 61.8mm (outlet diameter)

 

[John Wilde]

03' duramax LB7 Turbo Specs.
Manufactuer IHI (Water Cooled)

Compressor
Inducer 59.9mm (inlet)
Exducer 82.0 mm (max diameter)

Exhaust turbine
Inducer 68.0mm (max diameter)
Exducer 61.8mm (outlet diameter)

Thanks pro.....
turbo_chart

I am going to guess in the 800-900 range, with a little left.

We made 1021HP with twin 60-1s a million years ago.
That was a Duttweiler tuned Stage 2.

 

[big reazon]

Is this a good setup or should I save for some differnt turbos. This is a mostly street driven car that will make it to the track. I've been getting handled by these dang ricers around here in the monte carlo. I don't want alot of turbo lag if any. I decided I am going to use a Carburetor Solution Unlimited blowthrough 750 carb. I want about 800 to 900 maybe about the same in torque. With my current turbos will I get a bunch of turbo lag. Remember this is a streetcar so it will be running on pump gas. Should I use differnet turbos. Oh yeah and my bottom end will have the billet splayed main cap conversion. Is it possible to have a daily driver run mid 10s thats what I'm after really maybe even more. But shuld I use my current turbos or another set if I stay with my current ones will I have to worry about a bunch of turbo lag? I want to use my current ones though so I can use the money I saved to do something else to my car. Such as sound proofing and interior.

 

[cory ray]

twinn turbo 350

you should be fine with the eagle forged bottom end i have found thier stuff to be strong!! i also run the 5.7 h beam rod with a 3.48 crank!! the block will be fine at 800-900 hp range with the 4 bolt splayed caps in the 2 bolt block. i would not recomend anything over 900 hp with the stock chevy block even with a partial fill, as i found out the hard way!!! mine lasted about 25 passes till the block cracked around all the main caps and cracked two cylinder walls!!! the only thing i hurt was the block itself the crank,rods,pistons were all still good, i simply rebuilt the same combo in a dart block!!!!!! i also run the 210 afr heads they make great power,i made almost 1100 hp with a d1 procharger at 18 pounds!! as far as the duramax turbos i am not sure how the would run on the sbc but one of them on my 02 chevy diesel is impressive!!! good luck with your project and let us know how it runs thanks cory ray

 

[jhanson1750]

The only thing I would worry about is tuning the blow-thru. If they can get the fueling correct you should not have any problems, but they can be a pain in the a$$ to tune. We delt with great street manners but lean under boost or stupid power with fuel under boost but WAYYY rich otherwise. We finally compromised with fuel and 7psi on a 355sbc and were making @ 765hp. This was about 6 years ago so the head selection has come a long way. Oh you may also want to look at an alky system for insurance. We built one with an old rising rate regulator and an efi pump. took a while to tune but worked pretty good for us. Good luck Jon Hanson

 

[INTHEEIGHTS]

This guy got it prefected 1200 HP 23 LBS with PAIR OF BULLSEYE 66 MM TURBOS with a csu blow throw carb .

 

[INTHEEIGHTS]

heres there site. stevemorrisracingengines.com

 

[Tim Barnum]

I used a duramax turbo on my 98 Sonoma 350 project. It would spool to 5lbs with a 2500 converter on the foot brake . Unfortunatly the stock bottom end gave out before i got it to the dyno:biggrin:. Yes it made alot of power with just 5 lbs max boost on a blow threw carb system. I have a built 415 small block in there now without the turbo. I'm going to put the turbo system on the new motor soon. With 2 of them it would be crazy. But well worth the effort. Good luck