Twin Turbo Header

[Lextreme II]

I will have some time during X-Mas and would like to start a Twin Turbo header. Its most likely be log style with 1.5" from the header flange and i am deciding to use either 2.5" or 2.25" as the maine. This will be dual. What do u think. 2.5" or 2.25"? Those two headers will power two GT30R.

 

[turboandrew]

I would use what best matches the T3 inlet flange cross section on the GT30R. Most likely 2.25"

 

[stevechumo]

For the V8, I recommend using two Garrett T25s which used to be very efficient on Hondas. Each T25 will support 2.0 to 2.5 Liter engine easily. Therefore, combine 2 of those for a 4.0 Liter is good. It's compact so fitting them into the tight space would be nice. I'm planning on using these T25s on my SC400.

 

[200sx-v8]

Are you sure the t25s wont be a little too small. I have had that turbo on a 1.8, and it was too small. I switched it for a t28, and that was much better.

A t25 can't support more than maximum 250hp.

Unless it's the gt25 series you are thinking about.

 

[Lextreme II]

You can get GT25 with different compressor. Up to GT40 compressor size.

 

[stevechumo]

Twin turbo

Are you sure the t25s wont be a little too small. I have had that turbo on a 1.8, and it was too small. I switched it for a t28, and that was much better.

A t25 can't support more than maximum 250hp.

Unless it's the gt25 series you are thinking about.

You & Lextreme are right in all that. It's just a matter of how much hp you want to make. I never tried forced induction on these V8 but I don't think it'll handle more than 400hp without engine & torque converter rebuilt. Also, please remember that fitment is very important because there's hardly any room to fit the big turbos above the oil pan level. My car was lowered so I don't want to risk putting the turbos that low. There're several T25 kits on www.turbokits.com for Honda Accords that support up to 300 hp. I think you may use bigger A/R trim such as .62 to gain more flow. I never tried a T25 but I've had success with T3 on various Accords, Civics, and Integra. I'll stick with the T25s first instead of GT25 for cost saving. However, I'll still need to do some compressor mapping for the T25s anyway.

 

[R-Jay]

I don't think it'll handle more than 400hp without engine & torque converter rebuilt.

Ok just from that statement, i think you need to do more research... the engine will definately handle more than 400hp in stock form.... torque converter is another issue.

As for t3's and t25's, they're worlds apart. T3's are generally larger in all aspects than the t25's.

 

[Lextreme II]

Garrett GT Ball Bearing Turbos

This is what i was talking about http://www.lextreme.com/forums/showthread.php?t=2604

 

[88Alltrac]

The t25 is more suited to a 1.5L engine, way too small unless you go quad-turbo on a 4L engine. And that is a big waste of time. There is more to properly sizing turbos then you could imagine.

 

[stevechumo]

T25 turbo

The t25 is more suited to a 1.5L engine, way too small unless you go quad-turbo on a 4L engine. And that is a big waste of time. There is more to properly sizing turbos then you could imagine.

The reason that I mentioned the T25s because I'm only looking to make around 400hp. Each T25 can produce 200hp efficiently. Add them up to make 400hp. Also, I've seen the new T25 can max to 300hp on some Hondas including the F23(2.3 liter engine, 98-02 Accord, 4 cylinders), so I don't see why two T25s can't work on a 4.0 liter engine. I still can't forget about my turboed Accord with F23 engine. However, I used a T3 on it. Sorry, it's kind of off-track. Please think about the fitment & the pipe routing in the tight 1UZ-FE engine compartment and the heat from the turbo. If not properly positioned & insulated, the big turbo can do more harm than good. I haven't tried it using them yet, it's just a plan. Last but not least, I'm glad that all of you know about turbochargers. WELL, NO DEBATE, JUST DISCUSSION.....

 

[Lextreme II]

GT2871R = 400 hp (each)
GT3071R-WG = 450 hp (each)

The above turbos use have T25 turbine but larger compressor. I am interested in dual GT3071R-WG. That will be about 900 hp.

 

[chimpy]

screw the T25 all together, at LEAST get twin T28bb's from S15s

 

[thefastj]

agreed. use late model SR20DET turbo's.

or if u want new... look into GT28RS.

 

[chimpy]

or T518Z or T517Z's

they are nice sized turbos, nice power too, very resposive.

I am a personal advocate for Apexi turbos too

 

[edz]

Twin turbo's - pics of my setup

agreed. use late model SR20DET turbo's.

or if u want new... look into GT28RS.

I'm using two roller bearing watercooled turbos off a single turbo Nissan Vg30det , cheap and plentiful (rated at 190kw each, $350 ea if you buy a pair - SSS in Sydney).

Have included pics plus first manifold. Response wise they should be good, not after all out power, just want heaps of torque, and feeding them on lpg should be interesting!

 

[Zuffen]

Ed,

Will the manifold need a support bracket under the turbo back to the block to stop the mainfold from cracking due to vibration?

Also the bonnet will get a bit warm as the turbo will be close to the bonnet.

I'm surprised how much room there is in the old EH.

 

[edz]

twin turbos

Ed,

Will the manifold need a support bracket under the turbo back to the block to stop the mainfold from cracking due to vibration?

Also the bonnet will get a bit warm as the turbo will be close to the bonnet.

I'm surprised how much room there is in the old EH.

I'll definitely be putting a bracket in there under the turbo, that's why I left the plate sticking out (may cut that off and bolt straight under turbo or weld on manifold to support back to the motor.

Going to run 2 small bonnet vents straight over the turbos to feed cold air in while driving and hot air out when parked. Still want the sleeper effect.

A fair bit of room in theold eh yet! Mounted them forward to give room for a 3" dump plus wastegate pipe doen through each guard. I'm still looking and thinking, may move them back a bit as I'm worried about the stress of the turbo's hanging so far forward - a lot of leverage on the manifold. I'll see what I decide nextschool holidays in 3 weeks.

Cheers

Ed


PS: see you all in December for the garage crawl/meet in Canberra!

 

[88Alltrac]

I can't quite tell, but it looks like you have used 2 flanges for each manifold? I would suggest just cutting them apart to allow for thermal expansion, it can prevent cracking as well as a brace. (Although not 100% needed. I figure; it can't hurt.) They look good, good job! I am glad you went with the bigger turbos, you honestly will have boost almost instantly. Are you going to use a mixture of LPG and gasoline or just one or the other? I am considering LPG after I finish my hydrogen setup on my other car. LPG seems like it would be GREAT even just for fuel enrichment, and with an aftermarket ecu like mine, I can control it directly. What are you going to run your LPG system with? Good luck!

-Steve

 

[edz]

I can't quite tell, but it looks like you have used 2 flanges for each manifold? I would suggest just cutting them apart to allow for thermal expansion, it can prevent cracking as well as a brace. (Although not 100% needed. I figure; it can't hurt.) They look good, good job! I am glad you went with the bigger turbos, you honestly will have boost almost instantly. Are you going to use a mixture of LPG and gasoline or just one or the other? I am considering LPG after I finish my hydrogen setup on my other car. LPG seems like it would be GREAT even just for fuel enrichment, and with an aftermarket ecu like mine, I can control it directly. What are you going to run your LPG system with? Good luck!

-Steve

Hydrogen car - you're keen! Trying to beat Toyota and Mazda!

yes, 2 plates per manifold (cut with oxy by someone with a steadier hand than me!). You're probably right, I can seperate them and then get the whole lot milled flat on the mill at work or at my mates place.

With standard compression and roller bearing turbos boost should be very smooth and torqeuy!

LPG - I'm looking at running straight lpg (but have recently thought about running a small petrol tank in the boot side as backup).

My tuning guy who does turbo's and lpg cars all day reckons we'll try with a simple ignition module, lock the dizzy and set it up as you would a dissy car to keep it simple, but I'm not convinced yet - i'll wait and see. I was thinking of a simple ems ($900) so we can at least control the timing, he feels the gas simplifies it and it's unnecessary?

Have rotated the intake side on one turbo, currently trying to rotate the exhast side to get the centre bearing/oil/water feeds the right way. Any ideas, have drowned it in wd40 for 4 days, thinking of warming the exhast housing with the oxy this weekend, that should do it?

 

[vn1uz]

yeah give the exhuast housing a heat with the oxy
just be carefull you dont damage the exhuat wheel as they are ceramic in these turbos
i had to do this with a VG30DET turbo i had on my old mazda