SD turbo on a OBS truck

I know this has been discussed many times on here.
I decided to go with a SD turbo instead of a D66 mainly cause of the 3 inch airflow all the way through. I got new intake plenums and a fred give me a heck of a deal on a used turbo.
So, I have all i need except o-rings and exhaust donuts, I think.
Can anyone tell me about my IC pipes? Will I need to lengthen them? I know I asked a couple times before about the downpipe but will the OBS downpipe fit right up?
Anything else I need to know for those a youn's that done this?

Whose IC pipes are you running?

The OBS DP wont bolt right up. You'll need a SD exhaust flange to weld on to your DP. DI and Bean both sell them.

Do you have the SD pedestial?

Cowboy Steve

Thanks pard.
Well I was afraid of that on the downpipe.
Here's what I have.
SD turbo , stock and in good shape I plan on rebuilding it myself.
Sd pedestal and stock spider, downpipes, and exhaust collector.
The pipes I have installed now are just homemade pipes they fit perfect and I have a stock early 99 spider. So, ! hopefully they might match up pretty good? I'll see about getting the flange from Beans
W

The spyder should interchange fine

Cowboy Steve

Thanks Steve!

Early 99 spider is OBS size the late 99 spyder is bigger ,sorry to burst your bubble !!

He has the later 99+ spyder and 3" manifolds to put on with the SD turbo. He's running the factory manifolds and early 99 spyder with his OBS turbo. The IC piping shouldn't need to be changed if he's swapping spyders out. Still 3" hotside pipe outlets on both

Cowboy Steve

Misunderstood my bad!

I think everthang i got will work just need a flange for the downpipe.

the wife runs the d-66 with 3" everything (IC pipes,spider,SD intake plumes) and the OBS pedestal. i had the spider made, works and looks great.here is her 2" an 3" spiders together.(don't mind the pink it's her truck)

http://inlinethumb49.webshots.com/19632/2564866640094312740S425x425Q85.jpg (http://rides.webshots.com/photo/2564866640094312740CXdjVm)

but good luck with the project ahead of you

Thanks but? which is really better performance wise, durability and cooler egt's? I can do either but if the D-66 is really better I will just do that. The thing that got me wondering about the D-66 is you squeeze it down to 2 inch anyway and then back to 3 inch. I dunno I just need some advice I guess.
W

I don't think anyone will tell you the D66 is a better turbo than the 38R.
Both have the 66mm wheel and the 38R is a much more robust turbo. Guys with Stage-2's have eaten the D66, whereas the 38R can withstand just about any injector, even in a twin set-up.

If you swap the OBS exhaust housing onto the 38R (yes, it'll bolt right up) you can use the OBS downpipe. But if you want to keep the 1.0 housing, the OBS pipe won't work.
1.0 housing give better all around get-up and go, towing, etc.
OBS housing better for top-end performance. But still drives around fine. I haven't towed with mine yet and I don't have a 'cooler on that truck yet, either...

Even with the 2" stuff, the D66 will still flow loads more air. 1100 cfm vs. around 800 stock I think. The 2" isn't the hold up, even jumping up to 3" your turbo will still only flow 800 cfm.
Biggest thing on helping the D66's live is proper tuning so that backpressure stays low. That's why guys like rtxcoon and 3-starj.r. can beat on their D66 with hybrid injectors and have no problems.

Justin

Even with the 2" stuff, the D66 will still flow loads more air. 1100 cfm vs. around 800 stock I think. The 2" isn't the hold up, even jumping up to 3" your turbo will still only flow 800 cfm.
Biggest thing on helping the D66's live is proper tuning so that backpressure stays low. That's why guys like rtxcoon and 3-starj.r. can beat on their D66 with hybrid injectors and have no problems.

Justin

Good stuff there I am rethinking my setup and am thinking d66 and a nozzle change later on.

I don't think anyone will tell you the D66 is a better turbo than the 38R.
Both have the 66mm wheel and the 38R is a much more robust turbo. Guys with Stage-2's have eaten the D66, whereas the 38R can withstand just about any injector, even in a twin set-up.

If you swap the OBS exhaust housing onto the 38R (yes, it'll bolt right up) you can use the OBS downpipe. But if you want to keep the 1.0 housing, the OBS pipe won't work.
1.0 housing give better all around get-up and go, towing, etc.
OBS housing better for top-end performance. But still drives around fine. I haven't towed with mine yet and I don't have a 'cooler on that truck yet, either...


Words of wisdom.

Well, the plan is to do the SD turbo with a 91 mm wheel with the heavy thrust bearing. still don't know everthang about this rebuild yet but i think it will work fine. only thing that bugs me is if the shaft will hold up. I think that is more a SD turbo problem isn't it with the shaft breaking??

I would think the D66 inlet and outlet would cause more hot air. I'm probably going to go with the 38R because of durabiltity.

Thats another reason for going ahead with the SD setup when I get ready for a 38R it will be that much easier .

I flip flop but I will probably send an OBS turbo to majestic an have it rebuilt an balenced an leave it be till I can get a gt38r .

:whs:Thats another reason for going ahead with the SD setup when I get ready for a 38R it will be that much easier .

My engine is out right now and now is the time to change everything. Too bad my debt can't be changed.

I'm going to do what DZL Jim said to do. I'm going to put the OBS 1.15 housing on the 38R and still use my Exhuast brake. Just need to change the Pedistal and uppipes. Along with the spyder. Once the 38R is one it will handle the 200cc's and more.

where'd you get the 200 cc injectors? I had planned on building mine like Jim did but that may not happen now...
I should know more about this 91 mm wheel today.
Sposed to be a 62 x 91.
Anyone know the small side on a 38R wheel?

...Just need to change the Pedistal and uppipes. Along with the spyder.

If you can weld, have a buddy that can weld, or a shop that's reasonable, just add 1 1/4" of 2" pipe to each OBS uppipe instead of paying for new SD up-pipes...

I got the 200cc off another member that was put together at beans, I already got the uppipes just to make it easier, should be able to get the driver side manifold from swamps.

If you can weld, have a buddy that can weld, or a shop that's reasonable, just add 1 1/4" of 2" pipe to each OBS uppipe instead of paying for new SD up-pipes...

What are the OBS up-pipes, 409 stainless?

Don't think so.

I alreAdy got SD uppipes. I guess all I need is the driver's side manifold and then get the turbo parts, etc.

What year is your truck? Depending on the year, you may not need the drivers side manifold

Cowboy Steve

It's a 97. Thanks a lot for the help on this. I think I am gonna like this turbo it will be very comparable to a 38R just not ball bearing .

No need to swap the driver side manifold out then ;)

Cowboy Steve

How about a 96 then?

I believe the '96's meet the deadline, but Im not 100% sure

Cowboy Steve

thanks for the help steve

I have a SD exhaust flange coming from Red Smokey :evil

will be headed to the post office to send it off to ya today after work :D

Thanks Smokey!

No problem. Good luck with the swap!

I think you will be OK without changing the manifold but the pipe is going to be on the short side. This is from research not personal experience. I have picutes of the difference in those manifolds.

Tom

From not having the turbo mounted, I'm going to wait and see how much I am lacking before I get the DR side manifold. It looks like it may just fit. Hopefully.

On my 97 I did not change the driver side I just ordered sd up pipes and no leaks in 2 years

If I need to I will just weld an extension on the drivers side pipe. It will be a few eeeks till I get around to doing this. I still have to modify the turbo.
Tom I studied your article over real good. Thanks for putting it up it has been very helpful. :D You all been a lot of help!

On my 97 I did not change the driver side I just ordered sd up pipes and no leaks in 2 years
What kind of conditioner do you have on your swather Deerzilla? We decided we like the roller conditoner lots better.