::Twin Turbo'd Dohc Progress Pics::

[Penny-Benjaman]

Here are pics of my progress so far with my twin turbo?d & intercooled 3.4 Dohc that is going in my 94 Trans Am.

So far I have completed.

-All machine work to the block & heads
-Cryo treated rods and crank
-Fabricated both headers of 14ga Stainless Steel
-Fitted both TiAL 35mm wastegates
-Have a majority of the fabrication completed on the ?Double Barrel? aluminum intake
-Have partially completed the 4130 Chromoly tubular K-member that is need to be able to route the true duals out of the engine bay
-I also had to cut and reshape the bottom side of the cowl on my car, the intake was too tall otherwise and had not chance of fitting, but it does now

I still have quite a bit of work in front of me in order to get her back on the road.

-Install Haltech E11v2 programmable computer?and tune
-Finish welding on the ?Double Barrel? intake
-Fit twin throttle bodies to the intake
-Purchase custom slugs from JE
-Get headers/down pipes shipped off to Jet-hot for coating (leaving Monday)
-Route all aluminum tubing to/from intercoolers/throttle bodies
-Route all oil and water lines
-Mount both TiAL 50mm BOV?s
-Change routing of manifold heater hose and the thermostat housing, seeing that the hole for the thermostat touches the firewall as-is


Here's the link:

http://photobucket.com/albums/c133/PennyBenjaman/

-Let me know what you all think of it!-

[z34phoenix]

RE: ::Twin Turbo

[Guest]

RE: ::Twin Turbo

If you are using external wastegates, then why are you using turbos with internal wastegate housings?

[Penny-Benjaman]

Because those are the only housings that came with them, I really didnt have a choice otherwise I obviously would have went with blank housings. That reminds me of yet another thing I have yet to do...tap and plug the holes and remove the actuator arm...thanks!

[SappySE107]

Nice to see the progress on this project How is that intake setup since it looks like all 6 tubes run to both "plenum" tubes.

[Penny-Benjaman]

Actually on the intake the three runners on the driver's side bank are fed by only the drivers side plenum tube, and the same for the passengers side. there will be no physical connection except for a bridge for boost monitoring and MAP pick-up.

[SappySE107]

Ok, i figured that was what the 2 tubes were for but didnt see it. Are you boosting 1 side with 1 turbo? Any thoughts on unequal pressure from different banks causing problems? I would have something connecting both plenums, more than a tube anyway.

[Penny-Benjaman]

I had worries to begin with about unequal pressures between the two sides, but then I talked to the boys at Haltech and they put me in contact with a drifter that they sponsor that uses the same E11v2 to control engine functions and boost on his twin turbo'd car. He has a similar situation in which two turbo's supply two seperate plenums with no link for pressure equalization. According to him with how accurate the computer and accompanying Haltech solenoids are at controlling boost pressure that a problem has never arisen, mainly because this computer is capable of controlling twin turbo's using twin solenoids, therefore individually adjusting each wastegate in order to maintain proper boost for that turbo. He did stress however that I use top of the line wastegates to assure that proper exhaust metering is always maintained, hence the TiALs. So I guess the only real test for me is when I get it fired up and see how it runs, but I dont think I will have any major problems with that. Thanks for the potential heads-up though

[SappySE107]

Cool, glad that is sorted out for you then Looks like changing your timing belt is gonna be interesting as well:P Can't wait for a video of it running (oh please make a video!).

[OldSkoolGP]

So.....very.....evil!

[Baelrog]

What size turbos you using for the twins?

[Penny-Benjaman]

The ones on there right now a Mitsu TE04h's. They will give me 73% compressor efficiency @ 12psi. The down side to these turbo's is that, anything above 12psi and they are blowin too much heat to be useful, and they have a fairly restrictive turbine housing. I bought these turbo's when I had planned on leaving relatively stock internals in place and only blowing 10-12psi, but now I'm going to be pushing 14-16psi, so a pair of 14b's or possibly small 16g's will be in order to keep the pressure coming with reasonable efficiency at those levels.

[Scott205]

I love what you are doing, but wouldn't it have been cheaper to put a 4.3L 90 degree or a V8? or if you wanted crazy, a 3.8L Supercharged and Twin turboed engine

[DEI37]

Yeah, but then it wouldn't be a 60* V6, now would it?

[d.o.h.c]

my question is how is it going to fit. it looks like it is backwards. if you put that in a w body wont it hit the computer and the coolant tank. i thought it was easier to move the battery.