I am in a bit of a dilemma...my current turbo is in need of a rebuild to put it mildly, and I am just going to replace it with something different. I ordered a GT40R ball bearing turbo through Aspec and through no fault of theirs, the arrival date is a bit longer than planned. Long enough that my current turbo probably wont make it. Being a daily driver, I need to get something on this car soon and I am looking at other options, specifically the Innovative GT66BB turbo. The compressor maps are very similar. I called Innovative and the turbo is quite a bit more expensive, about $1895 with all the fittings, Vband and a Ptrim Inconnel turbine. Flows 70lbs. a minute. Pricewise it is stretching things a bit but it might be doable for me. I know that Greg from the dark side forum is an innovative dealer and perhaps I can get something slightly less expensive through him or another vendor. Unfortunately his webpage does not work.



Another forum member may loan me his GT40R until mine comes in (at which point my turbo will go to him) but barring that, it seems like the GT66BB would be the best alternative. I have attached the 66 compressor map.



I currently use the GT40R 88mm compressor (exducer) on my T78 and it makes wonderful (understated) top end power. Jason put down 460+ on pump. Good enough for me and I dont want less than that. Really. Am I making the right move here? Feedback appreciated....

Garrett GT40 compressor map

Innovative GT76. Someone said it'll literally bolt right in to a T78 setup sans the Vband connection. Just throwing it out there. Compressor map looks pretty good but I'm sure it's waaaay to big for my needs, no?

And I just want to add, it took me all of five minutes to post the above on this forum. On the other, it took me AN HOUR. Sort of a love/hate relationship. Great job nopistons guys!

Have you called ATP? That's probably where A-Spec is getting it from anyway, but it wouldn't hurt to call. They do say "usually in stock"



GT40R @ ATP Turbo



http://www.atpturbo.com/Merchant2/gr...s/gt40r-01.jpg

Actually Sean and Aspec have better sources than ATP. They're in the same dilemma. Essentially Garrett is the largest supplier of OEM turbos for the major manufacturers. Their performance division, according to Sean, represents about 2% of their total business. So....they manufacture all the OEM turbos they need until the quota is filled and then move on to the performance stuff. Leaving guys like me hanging unfortunately. ATP does have the .84 housing in stock however, but that may be a bit small for a rotary given the 88mm compressor.

Michel

Not to mention I'd rather support an RX7 shop :-)

Innovative is an RX-7 shop?



By the looks of it you could buy the GT-40R with the small housing now AND get the big housing later if you want for cheaper than the GT-66 from Innovative.



If you get the bigger housing later and don't like it or see more power, you've already got the small housing sitting there ready to go back on.



BTW, is it .84 or .95? They list .95 on their site.

A-Spec. RX7 shop. ATP list the .95 on their website but all they have currently is a .84. Wouldn't switching to a .95 housing later on force yet another downpipe reconfigure? Add the cost of the Vband, etc...it'd be darn close to Innovative price if not more. Unless the GT turbine housings are under $300. Right now a GT40R is essentially $1600 without the V-band. The Innovative is $1895 with everything. And the Innovative has a ceramic BB CRHA that rotates 360 degrees so it can be rebuilt if needed and quite easily so. What concerns me is that even Innovative's wheels may not be as efficient as the Garrett GT series. I can't imagine a relatively small outfit out-engineering Allied-Signal and it's vast resources which I'm sure include supercomputer modeling of compressor and turbine wheels. I'm now looking at the Precision Turbo stuff as well, the PT66 and PT67. www.precisionturbo.net

I meant that you were now looking to Innovative for the turbo instead of A Spec anyway.



Hasn't Sean provided your V-band and fittings already as part of the kit you bought from him?



I don't think you will need a new downpipe to change between those A/R ratios.

I would think that would depend more on the size of your turbine wheel. What is spec on the hotside of these gt40R's? Is anyone selling a non-ballbearing version (gt40?). You could run that .84 if you had something along the lines of a Q trim turbine wheel.



If I'm looking at these compressor maps right, it looks like the gt40 has a little bit more punch than the innovative gt66bb. Are you looking to replace the turbo long term or just in waiting until the gt40R is available? If you're just waiting, I'd try to find a cheap T04S or something to bolt on in the meantime.



So the GT40 compressor wheel is only 88mm on the exducer?...interesting.



How much are the GT40s selling for?

sorry, my computer is screwing up - I was trying to post that over an hour ago...

Yes, 88mm exducer diameter. Not too big really...but larger than the T78's compressor (GReddy) and it required quite a bit of machine work to get it to fit in the T78's compressor housing. Inducer is much bigger.



The plain bearing GT40 is also available with a .94 and larger housing so I'm not sure where the .84 housing on ATP's turbo comes from.



Turbo replacement is long term. I want to put it on, tune it, make miraculous hp and then forget about it for a couple of months at the least :-)



GT40's with the ball bearing center section are $1595.

i'd get the its gt76 dbb w/ a partial bridgeport. go for it man!!!

wow, you mean Innovative is including a bridge port with their turbos now? https://www.nopistons.com/forums/pub...1047683785.gif

Well heres my opinion.



Look at all the pro stock, pro import, pro whatever...all the guys running insane times/trap speeds are either running Innovative or Precision turbo setups. In my opinion you can't really go wrong. Plus if something does go wrong its handled here in the states probably. I think in the long run your probably better off with one of those. But thats just my opinion. https://www.nopistons.com/forums/pub...IR#>/smile.png

That's not really true.



Pro Import Cars W/ Garrett turbos



Garrett is from the US. Why would you have to send your turbo to a different country to be repaired? They're also the single biggest turbo manufacturer in the world, you should be able to get repairs anywhere. They log probably a billion miles (literally) every year in the US alone.



Turbonetics turbos are on a lot of fast cars, too. You'll note 99% of top level competitors get their product for FREE, so they don't care if it lasts more than one weekend or not.

I looked at the precision stuff but what they recommended didnt seem right (GT37). Theyre all pretty much into drag racing which is fine, but on occasion I have been known to hit the road race course too. I would probably be happy with the Innovative turbo. Question is, would my wallet? Three hundered bucks is still a good chunk of change which I could put to use tuning the car on the dyno, having my injectors serviced, taking the wife shopping....https://www.nopistons.com/forums/pub...IR#>/smile.png

Is it just me, or does the compressor map for the GT76 Innovative look just about perfect? Am I reading that sucker wrong assuming a flow rate of about 60lbs. min. for my engine and running from 16 to 24psi? Seems to be right in its sweet spot. That thing has to be a bitch to spool though.....

https://www.nopistons.com/forums/pub...#>/biggrin.png Well, considering it's compressor map seems to fall somewhere between the two wheels for the GT42 and Garrett calls those 850 and 1000 hp wheels, just what kind of engine do you have? https://www.nopistons.com/forums/pub...#>/biggrin.png



http://www.atpturbo.com/root/maps/im...42compress.jpg



BTW, I just thought of this. Depending on how Sean made the manifold, won't the GT76 compressor possible hit something? It's got to be a bigger diameter than the GT40R front cover.

I guess not the right engine! https://www.nopistons.com/forums/pub...#>/biggrin.png Going back to daydreaming now....

hence the need for a partial bp. cmon, u know u want to do it.

What I don't want at this point is to tear out the engine and tear it apart (for the third time) again. I just want to get a nicely sized turbo on the car and enjoy it for a bit without something breaking. https://www.nopistons.com/forums/pub..._DIR#>/sad.png



I really need to get something else as a daily driver.... https://www.nopistons.com/forums/pub...1047683473.gif

Didn't the first couple of guys that got the gt35/40 have to send them to NZ to be rebuilt? That was my reasoning behind the statement.

http://home.columbus.rr.com/dv8/t66.gif

http://home.columbus.rr.com/dv8/gt40r.gif

Those GT's have a nice fat compressor map at low boost, don't they? https://www.nopistons.com/forums/pub...IR#>/bigok.gif

Hoo yah! Baby got bottom!

Thats cause they dont know about Turbo Performance in Elkridge https://www.nopistons.com/forums/pub...IR#>/smile.png

Just a quick update, after much work and knuckle busting, I managed to fit in a Garrett GT 40 plain bearing turbo where the T78 once was. Nick Riefner at N-Tech was mostly responsible for the installation and he did an amazing job and an amazing amount of work (all night as a matter of fact!). The Garrett is the 82mm turbo with a .94 hot side and the less agressive of the two turbine wheels (both 77mm but different trims). Apparently the 88mm wheel ONLY comes with the 1.34 hot side or a 1.19 on special order. I'll have more later including a full writeup in another post.

i swear by ITS up and down, i havent built a street motor with one. but they seem to last forever in endurance race conditions, so it'll laugh at a street motor (no offense)