turbo upgrade question..

[Xjeepyjx]

Im sure that this has been asked numerous times, and im sorry but i looked for a answer but cant find it. i am restoring a 91 w350 with a non i/c baby h1c on the truck now. i am going to intercool the truck with a 2nd gen i/c. i also have a intercooled h1c , is it worth it to swap the intercooled h1c? are the inter cooled h1c larger?? can i make a one good turbo out of the two?

[cmann250]

The intercooled version is slightly larger. 50mm vs 54mm I believe. What pipes are you going to use and do you have the clamp on cast elbow for the outlet of the intercooled H1C?

[Xjeepyjx]

yea i have a v band and elbow, and all the hoses for both the first and second gen. i will fab my own pipes. ive read that the i/c turbos suck, the exhaust is smaller than the baby h1c

[oldestof11]

Huh.

If you have it and in good condition, use it. Not worth BUYING but better than the baby H1C.

What are your goals?

[CumminsPower59]

ive read that the i/c turbos suck, the exhaust is smaller than the baby h1c

The IC H1C's, there are two stock exhaust housing sizes, 18cm2 and the lagmaster 21cm2. Neither are really overly desireable, but a smaller exhaust housing is better

[Xjeepyjx]

how can i tell? the exhaust looks the same as my baby h1c, the compressor side is considerable larger. im trying to make the best with what i have until the truck is finished and i start tuning...

[bmoeller]

The 18.5 turbine housing has "18.5" cast into it. The 21 has "21" cast into it. Can't miss it.

If you push enough fuel, the 21 lights up decent and still keeps the EGTs in check.

[Xjeepyjx]

i found the 21 on the one turbo .but cant find it on the other h1c i think i found a little 18 stamped on. i looked on both my h1c that i have, all non ic h1c 18? so i should put the i/c compressor and wheel to the non i.c .

[cougar]

Put the 18 on the intercooled H1C.

[Xjeepyjx]

why cant i put the compressor wheel and housing off the IC on the non IC baby 18? i believe the compressor backing plate are the same..

[PToombs]

Would you rather change 3 parts or 1? Damn state employees and their "make work" mentality!

[Xjeepyjx]

the best baby h1c is already mounted on the truck... i figured it would be easyer to remove the compressor parts cause ive had issues in the past removing exhaust housings.. are the exhaust wheels the same from the 21 and the 18? i wouldn't think so... just saying lol. plus i dont think i have any more left over drain gaskets. i had a stock pile from all the cummins warranty i use to do , when the CM2150 ISB had all the turbo issues, they have you 2 drain gaskets per job, and i stopped collecting after 10. but i been giving them out to friends and using them on side jobs now i need them,

[PToombs]

The wheel is the same, the housing is larger internally. You can go from a 12cm to a 21 and only change the housing.
If you do swap the compressor wheels, remember the nut is left hand thread.

[Xjeepyjx]

hmm i just had a brain fart....what about balancing? isn't that why the nuts are trimmed? maybe ill just put the non ic18 housing on the IC h1c lol im a pain in the ass...

[PToombs]

Brain fart is right, I never did when I put on the 60mm wheel and it's been fine.