rx7legend

well today i took my turbo 2 to the dyno and im very happy with the results.
right now my only mods are safcII, rb turbo back and a walbro 255. the car run at 11 psi but when it reached 6400 rpms it drope to 5, if i had an external wastegate it should've been much better results. i did 220.23 whp and 200.17 max torque. ill post the dyno chart soon.

snowball

you can port your wastegate

jacobcartmill

iTrader: (6)

what does porting the wastegate have to do with anything? the wastegate has nothing to do with the boost dropping off. its a stock turbo...

anyways. decent numbers. my old TII made i think 222whp and 200wtq with the same mods so you're right on.

rx7legend

dude whats the function of the wastegate, i think that it is to maintain the psi. the internal one sucks. im going to put a 38mm ew. people say that is stupid but well see.

snowball

of course it only has to do with creep, but i never said otherwise.
its a cheap alternative to all the work involved in an external wastegate on a stock turbo.
can you even mount an external to the stock turbo?
and if so whats the point you might as well just go full aftermarket single.
no offense to the thread starter.

jacobcartmill

iTrader: (6)

i was just saying that boost creep doesnt even really seem to be a factor for the thread starter, so its kinda irrelevant.

also, about the external wastegate thing: its a waste of time and money to do all that work to the stock turbo/manifold setup. kahren's buddy on here welded a tial onto his stock manifold and i'm sure it worked well, but its on a stock turbo and manifold, so you wont see much of a power gain, it'll just control boost better.

Dom_C

Good numbers man

rx7legend

i know bro but im not doing it on the stock manifold i have another one, also i really don't want to change my turbo or anything like that, im trying to get the much hp i can by putting just relative mods. turbo back, walbro pump, safc etc. i really want to see how much hp i can produce whit my stock turbo. well see how this come up.

Wankel7

Not sure what you have for intake.....

But anyways your looking at what it can do....your boost is falling to 5psi at 6400rpm. Your turbo is tired.

Aside from putting on a fmic intercooler where else could you go?

James

rx7legend

im not thinking going front mount, im planning on an external wastegate, msd 6al , blaster coils and some other stuff. im planning on reaching 250whp at least. i think it can be done and thats what im aiming for.

Gaby scan

jacobcartmill

iTrader: (6)

that stuff isnt going to get you anywhere near a 30whp increase.

Wankel7

Gaby,

Like Cartmill said your not going to reach that goal with that. I am not trying to be an *** here....but it seems like you do not understand how a turbo works; specifcly the wastegate.

http://auto.howstuffworks.com/turbo.htm

That is a great write up.

James

jacobcartmill

iTrader: (6)

yeah... the fmic may get you 5-10whp, but the ignition and wastegate stuff are going to be marginal gains.

rx7legend

well see bro, i know that if the psi would've stayed in 11 psi and not drop, it would have been a big difference, from 11 psi to 5 psi i think i lost power there, and bro i know about turbos,and i know that if i put a better wastagate lets say a 38mm tial its certain that its going to hold the 11 psi and not drop, the local dyno that i go have a tII that has 500 whp so i think im in the right place, i told him that i was going to port my wastegate and he said that its a waste of time, that is better to go external, maybe where you live you don't see much TII's whit external wastegates on a stock turbo but down here ive seen it a lot, down here they dont port the iw they just put an ew.

thanks

Wankel7

Your right man I really don't see to much wild stuff.

You have the advantage man...you live in the PR. You guys have rotary in your blood

Anywho, the reason the boost is falling off is because of the stock turbo. That is just what happens. The compressor and turbine are not designed to make power past 6500rpm.

Dig up stock dyno charts and your going to see that. Now, maybe a good MBC will help you hold the 11psi longer. But it is really an uphill battle.

At this point....your wastegate is not your problem.

You never answered my previous question. Have you modified the intake?

Now if you have an OPEN intake and an OPEN exhaust and your boost goes from 11psi - 5psi by redline with a boost controler....your turbo is toast.

But if you have no boost controler try that before an external wastegate. At least that mod does not involve welding

James

andrewb70

You should read about what a wastegate does. It has nothing to do with HOLDING boost. The function of a wastegate is to release some exhaust flow to bypass the turbine in the event that boost pressure is going to HIGH. On a stock engine with a stock turbo where boost pressure is falling, a larger wastegate won't do anything. If the shop you are working with is telling you otherwise, take your money and run. Run FAST!

Andrew

P.S. Sorry..Didn't mean to steal the thread...

bigdv519

iTrader: (3)

A wastegate, no matter how big, isn't going to keep your stock turbo from choking your motor.

Link:

http://www.bankspower.com/Tech_howtu...egateworks.cfm