'90 760 Needs Ne Turbo...13c or .42/.48 T3?

I'm not sure if this newb-ish question should be in performance or maintenance, so mods please move if necessary .

Here's the story:

My '90 760's turbo needs to be replaced. It's got a good bit of in/out slop and I'm going to swap one of two possible turbos into it.

Option A: Replace the tired 13c with another 13c that's on the shelf that is practically new.

Option B: Replace the tired 13c with a .42/.48 Garrett T3 that came out of an '88 760. This one is practically new as well. I have all of the CBV stuff from the T3 and the rest of the plumbing that would be needed.

I realize that the T3 will require a different oil drain(which I have), and for the oil feed I would make up a -4 AN line.

Questions: Will the T3 oil drain line work with the 90+ exhaust manifold? I assume that both old and new style manifolds place the turbo in roughly the same position, but I'm not certain. I realize that studs will have to be added that are long enough for the T3 to bolt up to the '90+ manifold.

I figured I would do some light opening/porting of the '90+ manifold no matter which turbo I use.

I was also thinking about swapping out the cam for an A cam that I have.

Will LH2.4 get along with the A cam/T3 combo?

I know a 15G would probably be a better turbo to swap in there, but that's not an option as I don't have one; I'm going to use one of the above turbos.

Opinions or experience with this type of swap?

Thanks!

Option B is basically what im running in my car, only using B cam. But i am also using a 3"amm and bigger injectors, on e85. Lh learned, and loves it, as long as all componets are working properly, you shouldnt have any issue.

I vote for the T3! Better flowing exhaust housing!

Hi, T3 drain tube will end up being about 10mm too short when used w/ 90+. I am putting together a t3 on 90+ mani on a stand right now, and what i have so far is a spacer to go between the turbo and the drain tube. I just roughed it out of 1/4 inch steel plate. It basically looks like a drain gasket. My plan is to run a gasket above and below the spacer and use longer bolts to hold it all together. keep in mind I dont have this running yet, but it looks ok on the stand.
Dave

122ti said:

Hi, T3 drain tube will end up being about 10mm too short when used w/ 90+.

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Dave, you're correct. I mocked up the '90+/T3 on an extra engine on a stand and the stock drain tube isn't long enough.

It did appear that the 13c drain would work with the T3 if only the flange was sized for a T3. I'm looking into de-soldering the flange from a 13c drain pipe and adding one that fits a T3. I'll probably just make one from 1/4" steel if I can't find one and then solder it to the 13c pipe.

If all of this doesn't work, I'll probably just go back to a 13c. I could drill the oil drain out for 3/4" NPT and use an AN line with the T3, but I don't really want to deal with all of that.

I went with the t3 drain and my spacer thingy because it's so close and with the spacer i didn't have to mod any of my parts. That being said, it does bring the drain tube very close to the wastegate actuator arm. You might be on to something with the skinnier Mitsu drain tube. I don't have one to try. My only concern is that it wouldn't be big enough for the T3's oil volume, but someone else should chime in on that, I'm not an expert.
Good luck,
Dave

122ti said:

You might be on to something with the skinnier Mitsu drain tube. I don't have one to try. My only concern is that it wouldn't be big enough for the T3's oil volume, but someone else should chime in on

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Dave,
Actually, the 13c drain tube has a larger inside diameter than a -10 AN fitting, so it should be plenty big as lots of guys use -10 hose with no issues.

I guess this stuff was pretty overbuilt from the factory.

FYI, I've put a couple different T3s on 90+ manifolds w/o having to change the studs.

Having run both, I feel like the cars are faster with Mitsus if you're running stock boost levels. The turbo spools more quickly because its smaller.

towerymt said:

FYI, I've put a couple different T3s on 90+ manifolds w/o having to change the studs.

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Thanks, Mike. I was considering swapping to M10 studs as that's what size the T3's used, but it may be overkill.

The T3 didn't use M10 studs, it had bolts (you knew that, just saying). The M8 stud will be fine since you have the interlocking flanges. Since the T3 did have M10 bolts threaded into it, the holes are large enough to slip over the M8 stud w/o having to drill out the turbine housing.

I use M10 studs on my '90+ that uses a flat standard T3 housing. Probably not a requirement, but I got the manifold w/M10 already so that's what I'm using.

Mike, it appears that the M8's will do, but they look a little short and I'll probably replace them with ones that are a little longer.

Right now, the game plan is to silver solder up a 13c drain pipe to a T3 flange, port the '90+ manifold to match the T3 opening and run it.

If I can get the intermediate shaft out without having to pull the engine, I'm going to install a geared IS to run a block distributor and put an A cam in it. I think I can nudge the a/c condenser out of the way enough to do this. If not, I'll keep the T cam. I wish I had a slotted A cam....

t3

I have built two 94 blocks with 90 plus manifolds and t3 turbo's and never had a issue with the oil drain tube being to short. Did they by chance have a few different oil drain pipes for the t3 in the later applications. just was reading thru this post cause soon putting my super 60 spec t3 in my 94 940 to upgrade from stock 13c. Also I have also put nearly 8 t3 turbo's on 90 plus manifolds and never had to change studs they all worked great for me. thanks

Wren said:

I wish I had a slotted A cam....

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They show up on ebay from Penta sohc motors (eg AQ131). Probably even craigslist if you look for the boat motor.

I'm also interested in seeing how this goes since I want to upgrade from the 13c in my '90 760 too.

Xeroni said:

They show up on ebay from Penta sohc motors (eg AQ131). Probably even craigslist if you look for the boat motor.

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I was able to get the intermediate shaft out pretty easily. I just had to yank the radiator/intercooler and there was enough room to get it out of the engine after pulling the front engine seal cover and the breather box so I could pick up on the oil pump drive. I've got a non-slotted A cam that I'm going to put in it.

rwturbo said:

I have built two 94 blocks with 90 plus manifolds and t3 turbo's and never had a issue with the oil drain tube being to short. Did they by chance have a few different oil drain pipes for the t3 in the later applications. just was reading thru this post cause soon putting my super 60 spec t3 in my 94 940 to upgrade from stock 13c. Also I have also put nearly 8 t3 turbo's on 90 plus manifolds and never had to change studs they all worked great for me. thanks

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The oil drain that I have for the T3 came from an '88 760. I can't comment as to whether other B230/T3 drain tubes will work or not as I don't have any others. I think brazing up a flange on the 13c drain tube won't be difficult. I thought they were silver soldered, but they are brazed.

The studs on my '90 Exhaust manifold are too short to get a full depth of threads on the retaining nuts. I'm not sure if this is an anomaly, but that's what I've got on this one.

I have heard that Garret t3 and 90+ will make an extra 10 bhp over stock on a 760T or 765T - but that might only be in Europe where the 760T and 765T were the B230ET engine (and am I right the European B230ET will have had the A cam and 531 head anyway - memory may be playing me up there?) But then the B230ET in Europe was Garret anyway.