Looks like my turbo is a goner, what are some good options?

[teedoff00]

Hey Guys,

It's been a long while since I have posted, but I am getting back into the Supra as of late and been fixing and tracking down a few issues. I have been running a CT-26 60-1 Trim for the last 10 years, I had it rebuilt about 5 years ago and the car has around 2000 miles on it since. I have been having some smoking issues and after going through valve seals, pcv, etc I checked the turbo and its exhibiting some decent side-to-side shaft play, and there is a lot of oil in the intake/intercooler piping.

So... its time to move on.

What are the current best options? My only issues are... I'd like to have the turbo installed before the 8th of September. I plan on bringing my car to SIV and I have a tune appointment for a newly installed AEM V2 on the 8th.

What are my options? Bolt-on 57 trim from Driftmotion? Bolt-on 5531 or 5831 from SP Racing? Others? Or should I ditch the bolt-on all together and go with a t4 setup? The later may be asking for a lot given the short time frame.

Let me know you thoughts. Fortunately, I don't really have a budget for this, I just want something that will be a reliable street turbo that will give me comparable power and spool compared to the CT-26 60 Trim that I have. I drive this car mostly on the weekends and have never really taken it too the track.

Thanks!

Trevor

 

[plaaya69]

To me it sounds best to rebuild your current turbo. I usually hear bad things about the DriftMotion turbos from others that have bought them. I originally was going to go with a DM turbo kit but I ended up going with the precision 6262 Sound Performance bolt-on turbo which has been a very nice turbo and I have not owned it for that long but it puts smiles on everyone's face I let drive the Supra so far


What is your wheel hp goal you would like to be around?

 

[teedoff00]

Thanks for the input. Yah, I have been leaning towards the SP bolt-on as I think it would be easiest given my time frame and setup.

I don't have a solid goal persay, but if I could run low 400s rwhp i would be very happy.

So in your opinion whats the advantage of going for the 6262 over the 5831? Less lag intriques me... my motor has been rebuildt, but I decides not to go forged, so I really have no desire to push it too hard. Would the 5531 or 5831 do it? Or is the lag going to be comparable jumping up to the 6262. And if I were to do the 6262, is it worth the extra 900 for BB? Id assume the latter would be overkill given my goals.

Any advice appreciated.

 

[Piratetip]

To me it sounds best to rebuild your current turbo. I usually hear bad things about the DriftMotion turbos from others that have bought them. I originally was going to go with a DM turbo kit but I ended up going with the precision 6262 Sound Performance bolt-on turbo which has been a very nice turbo and I have not owned it for that long but it puts smiles on everyone's face I let drive the Supra so far


What is your wheel hp goal you would like to be around?

When did you pick up the 6262?
Last time I talked with SP they didn't have anything for the MKIII anymore.

 

[plaaya69]

I bought it used with about 3k miles on it from a member on SF but it is in new condition. When was the last time you talked to SP? I always check in on their site and it says that they still have 4 available versions of this turbo.

http://www.spracingonline.com/store...t_87-92_MKIII_Supra_Direct_Bolt-On_Turbo/3143

 

[teedoff00]

I just talked with them this morning... they are all still available including the 6262 in journal and BB. But they all have 4-5 werk lead times at best, nothing instock:-(

I guess I'm going with a 57 trim CT-26. At my power goals and running pump gas, a larger turbo would probably be overkill...

 

[Piratetip]

Yeah I talked to them last year.
Interesting they still have something now at least.
Might have to pick one up before all new bolt on turbos besides the CT-26 are extinct...

What did they price you for a journal and/or a BB now?

I would prefer a 6262, its all about air flow and compressor maps.
Would rather run a 6262 at lower boost than a high strung 57 trim, going to last a lot longer.
Lag can be countered with a number of methods, don't have to sacrifice much of anything there.

 

[teedoff00]

Their website has all their current options and pricing.
http://www.spracingonline.com/store/Precision_MFS_CEA_Billet_87-92_MKIII_Supra_Direct_Bolt-On_Turbo/3143

Alec at SP thought the 6262 would be a little much on pump gas. He thought the 5831 would be a good inbetween. I really did want to give the SP bolt on a try, but the lead time just wont work for me.

 

[suprarx7nut]

Yeah I talked to them last year.
Interesting they still have something now at least.
Might have to pick one up before all new bolt on turbos besides the CT-26 are extinct...

What did they price you for a journal and/or a BB now?

I would prefer a 6262, its all about air flow and compressor maps.
Would rather run a 6262 at lower boost than a high strung 57 trim, going to last a lot longer.
Lag can be countered with a number of methods, don't have to sacrifice much of anything there.

Do you know if they have compressor maps available for the SP bolt on turbos? Is it similar enough to another map to just assume they're the same? I've been trying to nail down my turbo choice, but haven't seen many maps for anything bolt on.

 

[teedoff00]

As far as I was able to research no Compressor Maps are available. They just ask you for your horsepower goals... lame

 

[Piratetip]

Yeah I don't have any compressor maps.
Garrett compressor maps are very easy to locate, these not so much.

Unless someone has an inside source I see no compressor maps for a PT6262 CEA.
I doubt if precision ran the testing required to create these maps.

 

[Suprapowaz!(2)]

I'd wait the lead time for a turbo i really want. Even if that meant missing that SIV event. Don't compromise for a weekend event. When that weekend has come a gone you'll be wishing you went with the better turbo. Be patient.

 

[suprarx7nut]

Yeah I don't have any compressor maps.
Garrett compressor maps are very easy to locate, these not so much.

Unless someone has an inside source I see no compressor maps for a PT6262 CEA.
I doubt if precision ran the testing required to create these maps.

That's such a shame. That's a pretty essential part of the turbo decision in my mind. A single number HP goal (with no mention of RWHP or BHP) is pretty meaningless if you really want to size your turbo correctly.

I'm trying to find the best solution for 500rwhp, but I don't want something that's good for far more, or obviously less.

 

[Piratetip]

Yeah it is very tough to see where your air flow targets land with respect to the turbo efficiency map.

I find it very strange that this information is not available as these compressor wheels appear to have quite a good reputation.
Its the fly by the seat of your pants type situation.
You could somewhat indirectly measure turbo efficiency by mapping compressor out air temps at varying loads/airflows/boost pressures.
Effectively mapping intake air flow and boost pressure to compressor out air temperatures.
But it would be a very rudimentary type 3 dimensional scatter plot or similar.

Without testing the turbo on the bench with the sophisticated equipment required to actually create a real map its a long shot.

 

[suprarx7nut]

Yeah it is very tough to see where your air flow targets land with respect to the turbo efficiency map.

I find it very strange that this information is not available as these compressor wheels appear to have quite a good reputation.
Its the fly by the seat of your pants type situation.
You could somewhat indirectly measure turbo efficiency by mapping compressor out air temps at varying loads/airflows/boost pressures.
Effectively mapping intake air flow and boost pressure to compressor out air temperatures.
But it would be a very rudimentary type 3 dimensional scatter plot or similar.

Without testing the turbo on the bench with the sophisticated equipment required to actually create a real map its a long shot.

Not knowing much about the design process of SP's turbo-making myself, I guess I'm surprised SP has a casting different from the CT26, but still bolt on and doesn't produce flow data or a map for buyers. They obviously invested some serious work on it, right?

Perhaps this all leads to bigger questions I have about the bolt on turbos that would be better directed towards SP themselves. IE- Did they design the housing casting? If borrowed from something else, what is it? If they did the casting, what info can they provide? Surely there was some significant engineering that went into it. Is it similar to a known brand's housing that we could infer info from with the known brand's compressor maps with the same wheel? What flow can the wastegate reliably regulate?

I love the SP product offering... just really don't like the lack of info.

 

[Piratetip]

I cannot claim to be 100% correct on this but SP does not appear to do much beyond some machining work...if any at all.

The PT6262 CHRA is an off the shelf turbo from Precision Turbo.
The compressor housing and CHRA are done by Precision, they look exactly the same as the SP photos.
http://www.precisionturbo.net/products/details/Street-and-Race-Turbocharger---PT6262-CEA--174-/245

The question I cannot answer directly is where they are getting the new CT-26 turbine housing.
Someone is casting this component that is able to bolt on to their CHRA and have the CT-26 manifold and downpipe bolt pattern.

There are other vehicles they offer this same type of solution for:
Turbine housing options:
- T3 .63 or .82 A/R with 4 bolt (2.5") discharge
- T3 .63 A/R with 5 bolt discharge (with or without wastegate hole)
- T3 .63 or .82 A/R with 3" OD (outer diameter) V-Band discharge
- V-Band inlet .64 or .82 A/R with V-Band discharge
- T4 Tangential .58 or .68 A/R with 3 5/8" OD (outer diameter) V-Band discharge
- T4 Divided .84 A/R with 3 5/8" OD (outer diameter) V-Band discharge
- Mitsubishi .63 A/R
- Buick .63 A/R
- GMC Syclone/Typhoon .85 A/R
- K26 .82 A/R

I would guess at some point they probably had listed the Supra turbine housing in that list.
It is likely volumes dropped off enough to remove it from the list.

SP appears to me to just be a distributor of the Precision product.
Precision probably has more information on what work goes into creating this product.
As well explains why they have such a lead time now, getting it from another company.

 

[Suprapowaz!(2)]

Not entirely sure if it was Precision Turbo, but I could have sworn they've already told the public why they don't have any compressor maps/info on their turbos. It was to keep the cost down on their turbos by not investing in all of that equipment and R&D that would result in passing the savings to their customers. Not sure which forums I caught it on though. I do remember a thread a out this same subject, and PT came in and explained themselves. If you guys remember Precision Turbo used to be a distributor for Garrett turbo. They started modifying Garrett turbos and selling them as their own. Back in the late 90's I had a Precision SC61. Turns out all it was was a Garrett T04e 60trim with a ported/polished compressor housing inlet & outlet. Then they ID'd it with a dremel scribing on the compressor cover. Now they make their own turbos.

 

[Piratetip]

Lots of questions on these turbos can be answered here:
http://www.supraforums.com/forum/sh...Turbos-Gauging-Interest-**POLL-INSIDE**/page2