i was just reading the thread about turbo cpl number went to chk mine and chk to see if there was any shaft play and there is. just a little i guess its time to do some work since i have a 21cm. do they make rebuild kits for the bearings and should i change the housing to a 16cm? this truck is my daily driver and work truck for my side work.

91.5 I/C auto 3.55 4x4 so going with soon going with 4 inch exhaust tues of next week

 

yes they make rebuild kits I got mine from Gillet diesel service for $74 deliverd to my door. i would go with the 16 if that is what you want/ can afford a lot of guys seem to be using gated 12s with improvements.

 

im going to add new injectors and gauges buy summer time

 

do you havw gauges on, boost and pyro. the improvement i was talking about were to the exhause housing the make the wast gate larger and other things. what else does the truck have please add to you sig tranny, rear end ratio. then the other guys might be able to help even more I'm still kind of new.

 

thanks for giving a little more in your sig, and I've seen other question just on turbos for the old trucks, choices,choices,choices. try searching 14cm. lots of explaination on sizes.

 

just a lil advice dont go with the 12cm that is what i am running on mine i have a 14cm gated housing and the valute is a touch bigger on it but the spool is still the same all depends on what you want with the 12 i have notice a lot on the low end but dosnt help on the top end

 

was the 12 you were using modified?

 

If your turbo is stock, it should have the 18.5cm housing. Only 92's got the 21cm. Stepping from the 18.5 to the 16 is a waste, especially on an automatic truck. There is nothing wrong with a 12cm/wg housing. With the divider drilled and some porting, it will easily hold my engine to 25psi, and that is with a maxed pump, ground AFC foot and larger non-intercooled injectors. The quick spooling is a must for a 5 speed truck that tows. If I had an automatic, I'd stick with the 18.5, JMO. It's hard to get too excited about hot side changes on the H1C because no matter which one you choose, it'll only cool about 250 rwhp on a working truck, even with a hybrid upgrade on the cold side. The size of the exhaust housing simply dictates where the power is made. Small housing=good spool and around town manners. Gets the engine up on torque peak quickly which is good for getting loads moving. A 12 (or 14) will choke a bit on the top end...this is where you've gotta be honest about your driving style. I spend most of my time below 2500rpms, so the 12 works for me. The occasional high temps on the top end are a calculated risk and, after swapping from the 12cm to the 18.5 and back again half a dozen times, it's not that much different temp-wise, yet the 12 makes the truck so much more fun to drive under everday circumstances. Don't get me wrong, if I had an auto, I wouldn't even bother with the 12, especially if I were looking at injectors. As for the 14wg, for what they cost, you're already halfway to a better turbo--s-300, etc. As for the play in your turbo, as long as the compressor wheel has not contacted the housing, you're in good shape. The shaft runs in a bushing that is bathed in oil. When the engien isn't running, the oil drains out and there will be some play.

 

Correction on the turbo housing/year thing, the 91.5's to 92.5's had the 21cm housing. 92.5 on went back to the 18.

 

its a 91.5 i think i think its a 21.5 so going to a 16 would be good i dont think i have a 18. last night i spent some money on a stage 4 compressor from HTT and still thing about the 16 cm?

 

I've gotta say that I've never seen a '92.anything with an 18.5cm housing, but then again, I haven't seen every '92 either

Confed, supposing that you do indeed have the 21cm housing, a 16 would indeed make the truck feel snappier. My concern would be its ability to flow the large additional volume of air that the stage IV is going to push though the engine....and that volume will also be dictated by your injector choice---what are you leaning toward? What does your truck do? Daily driver, always hooked to the trailer, fun-time toy?

 

My '92 came with the 18.5 cm housing, just thought I'd throw that out there.

Dawson

 

you will probaly want the 16cm with that compressor. tomd has that set up i beleive.