I have a motor built to handle a good deal of abuse (build by KDR/Speed1) but no snail to match it. I have decided to bite the bullet and have a custom manifold/dp and other related piping done by someone that knows what they are doing; however, I havent settled on a turbo to build around.

I am looking for a list of possible, off the shelf turbos that would be reasonably well matched to the rx8. T618z would be on the small end. I currently have what would nominally be a 620.

My constraints are these:

1) I would like to install it at the exhaust ports.

2) An external wg is not a problem. (Though I would rather not incur the extra expense.)

3) Ballbearing, water-cooled unit is a major plus.

4) Spin up no sooner than 4250 rpm and no later than 5000.

5) Flows somewhere north of 300g/sec or 40#/min at >70% eff. and 14psi, but less than 500g/sec-65#/min.

6) Can include any make, model that can be accessed off-the-shelf.


As usual, if you dont know what the **** you are talking about, please keep it to yourself.

 

gtx3076

 

are you looking for a top mount or bottom mount setup?

 

Brettus, that is number one on my list, but I was hoping for a little lessonage in HKS, turbonetics and others.

I am really not interested in a top mount. I want it as close as possible to the exhaust ports as per 1) on my list.

 

NGO has an HKS somefing - ask him about it

 

the Garrett website has a decent tutorial for beginners

GTX3076R

otherwise if you insist on the Greddy position quietly wait for MM to finish your 2+ year old Greddy upgrade, but if you cant wait then BNR also has a Greddy upgrade, same make as the original but a hybrid I believe

 

Carbon - do me a favour and measure the wheel on your current turbo pls .

 

Team: Read it already and as I said, I have the gtx3076r on top of my list. I am looking for pro/cons on other manufacturers.

How long would you have me wait? 2 more years? I dont think so.

Brettus: I will do detailed measurements wen it is off the car.

 

http://www.turblown.net/store/index.php?productID=248

with this turbine housing;

http://www.turblown.net/store/index.php?productID=229

and this compressor housing upgrade;

http://www.turblown.net/store/index.php?productID=127

 

Why change housings?

 

ok so you want something that will be located where the Greddy kit puts it?

 

Essentially, yes. I have a bit of latitude in that regard, but for the most part, this is where I would like it to go.



I had a little time to do some reading today with regard to picking a proper turbo for the application. I am starting with two general requirements. Quick spool-up (, i.e., usable on-boost at not much more than 4250rpm), good auc on a torque v rpm plot and good hp numbers at high rpm, perhaps upwards of 400hp. Use will be both street and track so peaky hp/ torque is to be somewhat avoided.

Using a conservative estimate of 8hp/lbs/min and shooting for 50lbs/min, the gtx3076r might just be able to reach that at 70% eff and 14psi. Taking the next step up into the 35 range, flow jumps a bundle and the turbine plot of turbine flow v press ratio (not the compressor map) suggests (maybe, if I am reading it right) that I would find it difficult to spin as early as I wish to.

I think what I am looking for is something that can still be wrapped in a t3 housing, spin as quickly as a 3076 but flow just a tad more than what the 3076 does.

 

sounds to me like you're looking for a hybrid close to what I'm running on my mirage...check these guys out:
click here

look at the T3/T4 stage 3 with the .48 a/r exhaust side. That's the exact one I have on my mirage. Insane little turbo! It swears that it's a GT30...I just go with it because I don't want to hurt the turbo's feelings. haha Of course, they have other sizes. that company has decent turbos for just about any need. Not to mention the pricing is fairly decent. I haven't had a problem to date with that little guy.

 

FWIW - the GT3576 on an FD will spool by 4000RPMS. SO a renny should be pretty close.

 

So a question about that. As some of the 35 series are quoted as fitting in a t3 housing, can I assume that it would fit?

Also, besides surge and lag, what are the downsides of having too much turbo?

Take a look at the compressor map of the GT3582R. To me, it looks only slightly oversized, but very close to what I would want. Is it? Can I estimate spool up from calculating estimated/normalized exhaust flow at 4000rpm (same as unboosted intake at 4000rpm normalized to temp) using their turbine plot?

The way I figure it, the GTX3582R gives me exactly what I want. Reasonably quick spool up if Kane is correct that the 35 turbine is not so overly large that it lags, but also pushes plenty of air at high eff. I am thinking perhaps this is the one to go with.

Anyone want to argue with me??

 

Nope I like it, the packaging may be tough.... if you want it down low. If memory serves, it is a pretty big boy!

 

1/Do you have the fabrication skills to make it happen ?
2/Alternatively are you prepared to spend a bucket load on someone who does ?
3/Do you have the mechanical skills to follow thropugh with trouble shooting etc once it is fitted
4/see 2 again
5/Do you have the tuning skills to get the best out of it or are you prepared to learn from someone that does ?


If answer is no to any of the above then the exercise will end up like practically every other similar projet we have seen on this forum ..............

 

1) I do not. Car is getting shipped today to someone that does.
2) Bucketload? Define.
3) To an extent. It should be pretty worked though when I get it back and there will be considerable help from the mech that did the install.
4) Again, define. And two whom are you refering in this case?
5) To an extent. It should be pretty worked through when I get it back.

This is going to happen. It is going to be a very interesting build. Trust me on that.

Kane. WHen you say big boy, are you refering to the compressor? The turbine fits in a t3 housing, which should fit. I am not sure how to pick the compressor however.

 

anything is possible given the fabrication.

the GTX3582R has a huge compressor housing. with a low mount it will probably require a custom motor mount to provide extra clearance.

regardless, the GTX3582R does sound like it would suit your needs and constraints 3, 4, and 5.

 

About this big.....

 

the greddy is only a T25 so the housing is bigger than that. however I think AUZOOM is using a T3582 variant on a low mount manifold. from what he has posted it was probably repackaged by the people who installed the turbo for him.

 

ALright. I think I have settled on one that meets my needs! Might actually flow as good or better than the GTX3582, but the GTX3582 itself doesn't look like it will fit my application (at least not at the exhaust ports. Might be fine otherwise.)

Thanks all for your help!!!!

 

I agree..go with satin's hairdryer!!! won't be disappointed

 

That car was stupid fast too.... even while still stupid rich and half tuned it was stupid fast

rofl, fail

 

Yeah, I loved that thing....***** to the wall.

By the time the WG opened to ATM.... you couldn't even hear it cause you were going "oh ****, oh ****, oh ****, oh ****,oh ****, oh ****,oh ****, oh ****!"