I have a 91 non ic w/ a baby H1c(that's what they're called, right?). 3" inlet. I have a spare turbo from an intercooled truck, is it a noticeable gain to switch them? I was going to make a new crossover pipe also. Its eventually getting an intercooler too. I've had a lot of intercooled trucks, this is the first non ic I've played with. Thanks

 

best of my knolege the H1c is the same the i/c ones have the 21cm exaust and 4in intake i think?

 

Keep your 18 cm housing off of your old turbo. It will spool faster than the 21 cm housing on the newer turbo. If I was going to go with a different turbo, i would get a WH1C, or an HX-35, because they are wastegated. If you want to run a lot of fuel, you will need a bigger exhaust housing for the newer turbos. If you are running relatively stock fuel settings, the 12 cm housing on an hx-35 is great, because it spools fast (according to others on this site).

 

If you have both the turbo's then it would be an ok swap. I don't think you will notice a big difference though. As previously stated you need to make sure that the exhaust housing that you use is the 18cm one and not a 21cm one.

 

I'd def. be keeping the 18 cm, isn't the baby like 50mm and the reg. is 56mm?

 

89-91 baby- 50/60/18.5

91.5- 54/60/21

92- 56/60/21

93- 56/60/18.5

stay AWAY from the 21cm housing.

 

Can you tell me where you got this info from? In 91.5 and early 92, the engines share the same CPL, 1351, but have 2 different size turbo wheels?

 

So ideally, you want a turbo from a 93.

 

I'm pretty sure someone has measured there 91.5 turbo and it came out to 54.. someone measured there 91.5 turbo and got 50mm with.the info has been ran across over the years in arguments and such. All i know is any stock H1c is still a stock H1c,

91.5's were mystery trucks, just a bunch of left over crap from the early years.

But yea you want a 93 turbo. stay away from the 21cm housing.

 

My cousin has a 91 non intercooled, with an intercooled style grill. It also had a 50mm/ 18cm. My 92 had the 54/21. I measured both of them with calipers. So i'd stay away from the earlier stuff, you never know what your going to get. Go with the 93 56/18, it seems to be pretty consistent.

 

Its no big deal to change an exhaust housing... I have an extra turbo from a 92, if time permits I'll measure it. I actually have one of each 91.0-93, could measure them all if I got bored enough.

 

measure them all.

HTT says all 350 trucks got 54mm compressors. idk

why would a 92 have a 54mm compressor?? wierdd

 

my buddys 93 had a 54 mm wheel


And to answer the OP question I would put it on, Its bigger than whats on your truck and you already own it

 

I probably would, if they were just extra turbos laying around. They are all running trucks. I am going to measure my extra 92 turbo though.

 

I've put a 1992 H1C I/C compressor housing and wheel on my original baby h1c turbo and with increased fueling I did notice some better performance... The problem with the h1C 54s when you put fuel to them from non i/c sticks cranked up is you get major major flutter/surging on the low end. (no MWE slot) That said, when it actually does light up on the high end of the RPM, it is much better than that squeeling 50mm wheel.