HX-35 Turbo

[tugboatphil]

I notice that some 1st Genners have added the newer turbo. Without it being modified by PDR, is it worth the time and work to add it? If so, what kinds of modifications are necessary to make it work on our engines? Does it fit with our exhaust housings? Does it need a wastegate? I apologize if this has been addressed before.



Thanks.

 

[dpuckett]

The housings are interchangeable. On intercooled trucks, it is a drop-in replacement. On non intercooled trucks, it requires some creative engineering to plumb it, along with needing a new intake hose from the air filter to turbo. I put a PDR HX35 on my early 91, and am happy with it. The old one had 1/8" endplay, so it needed replacing anyway. I have read that the HX35s are more efficient in higher boost apps than the H1c. SOmethign along the lines of 33psi vs 22 or so in the H1C. THese are guesstimates based on the findings here.



Unless you plan to majorly BOMB it, or your H1C is worn out, I would say a stock unit may not be worth it, but a hybrid may well be. Go with a smaller housing either way. I had good luck with a 12 on a daily driver. I'd go with a 14-gated or 16 NG for towing.



Daniel

 

[tugboatphil]

Thanks, Dan!



It looks like you've got a pretty good setup on your truck. I still haven't gotten a rear end for my 90, but plan to get her back on the road. The oldies are sure enough the goodies!



Phil

 

[dpuckett]

Originally posted by tugboatphil

Thanks, Dan!



It looks like you've got a pretty good setup on your truck.

Thanks. I still need to get an intercooler before returning to the high country. EGTs here at 400 ft peak at 1300; can hit 1400 at home. MDW is supposed to get me a 12 housing form his truck; then I can tell you how the PDR HX35 works with a non-stock housing. THe PDR HX35-18 spools a hair slower than a H1C-12, but catches up pretty quick. I can get to 25 psi quickly enough, and I have the pump set to delay fuelling because of the injectors- they need rebuilt/ replaced/ upgraded and I HATE laying a cloud, unless 90% of it goes in the window of a hoopty- mobile with his stereo thumpin. (Getting better at that, too).

Happy BOMBing.



Dan

 

[BushWakr - RIP]

Just for comparisons' sake... ...



I installed the HX35 with my 14cm N/W housing in place.

My dyno run was long but still, I hit 1700*F ... wayyyy too hot.

On the highway, at WOT in OD, I would hit 1600'ish, at about 100 mph with 40psi boost.



I changed out the 14cm and put on my 16cm housing... at the same time I did some modest porting of the inlets/outlets on the exhaust manifold, as well as the inlet to the 16cm.

With no changes to fueling/timing etc, I now run about 1450*F at WOT, at 100 mph, with about 36/37 psi boost.



Cooler, and slower to come up to that temp as well.

I'd suspect that the 18cm would likely repeat that result, with a bit of plus or minus.



The spoolup was certainly slower with the 16cm, and I had an increase of idle/very low throttle smoke with it, over the 14cm.

I am going to do some work on the 16 to speed up the spool rate, and see if I can get the low end smoke to go down to the 14cm level.

If I am successful I'll post results.

It's also my intention to do some drive pressure tests with a 12cm WG, 14cm N/W, and the 16cm N/W to compare boost/temps/drive pressures.



For now, I'd suggest that you may want to go easy with a 12cm if you already have EGT issues, which will be compounded at higher elvations...



Bob.

OLOAC.

 

[Steve Campbell]

Daniel Puckett.....

it sounds like that PDR-35 is working good for you.

 

[dpuckett]

Re: Daniel Puckett.....

Originally posted by Steve Campbell

it sounds like that PDR-35 is working good for you.

Yes it is. I would recommend it highly as a good upgrade if your H1C is showing some age. I can hit 30 psi here at sea level; peak EGT is about 1200. Since I dont do a lot of towing, or racing (stoplight-to-stoplight against ricerboys is NOT racing- it is putting them in their places), I think a 12 would be good for me for now.

Daniel

PS- soon as Mom gets back with her camera, I'll post pics of how I got the HX35 to work with no intercooler, and no modifying (butchering) of the turbo itself.

 

[R.E. Miller]

$.02

I have been running the 12 on my truck, and if I keep the thing, I will be removing it. At high rpms (i. e. 65-80mph) it becomes too restrictive for my likes. No it might be that our heads are non-swirl, and the fact that the 12 is small together, but it just isn't worth it to me. My dad's truck has the 16, and off the line, their is a little lag, but rolling down the road, it just kicks



Good luck all,

Russell