Engine/Transmission (1998.5 - 2002) Another Turbo Upgrade Question

[BSKI]

1999 Ram 2500 automatic transmission with ATS Triple Lock T/C and Triple Lock Commander, 80HP injectors, 4" exhaust, afe proguard 7, hypertech power programmer



I tow some tall hills 15K toy hauler, I have more throttle than EGTs will allow, Lots of turbo Bark when the T/C locks up and blowing boots right and left. Ordered the High Performance boots from piers but am struggling with the Turbo upgrade.



PDR HX35 $650

PDR 14Cm2 housing $415



HTT Stage III upgrade $425

HTT Stage III Upgrade with 14Cm2 housing $660

HTT HX35/40 swap with 14 Cm2 housing $945

(includes new bearings and quick spool mod)



Now for the questions,



HTT uses a 60mm high flow wheel and PDR uses a 58mm wheel. PDR says more flutter and bark with the 60mm wheel? Any feedback?



Do I really need to upgrade to the 14Cm2 housing, in other words will the 14Cm2 housing make that big a diff in EGT at higher RPM and of course spool lag and hotter EGT at lower RPM? I am hoping just a 2cm upgrade will be just right.



I know PDR has good stuff and is a leader in the industry, HTT has good prices and appears to build a bullet proof turbo... . some help would be greatly appreciated



I want the best all around turbo for towing HEAVY and of course drivability. I also want some room for growth, (new chip). From everything I am reading it doesn't sound like this is possible.





Thanks



B

 

[PC12Driver]

My advice would be to approach it in steps. Get the PDR or the HTT and try it with your 12cm housing. If your wastegate is getting overrun (can't control boost) then go for the 14cm. As long as the wastegate keeps boost under control, the drive pressure (exhaust backpressure) will not increase. But this is where I'm not a fan of Holset turbos; they only 'gate 3 cylinders. You can drill the divider and 'gate all 6, but you'll loose a bit of spool.



Then there's the HTBx series of turbos from HTT. The HTBG is a sweet little turbo. You can run a 12cm housing for great spool, and the compressor is good to the mid 40's of psi. And the housing is factory wastegated on all 6. TDR member Clmsnow ran a HTBG/14 for a while, and switched to a 12cm housing and egts did not increase (the wastegate does a great job of keeping drive pressures in check), but he gained a bunch of response, which is what you need for towing (his WFO temps were mid-1300 on a 450hp-ish truck). And HTT has a great upgrade program if you ever want to bump up to an HTB2 or change your housing. The downside is that you need to change your downpipe, and turbine mounted exhaust brakes will not work.



Sizing a single turbo is about trade-offs and deciding where you want your power delivered. Increasing the size of the compressor and/or increasing the size of the housing will move the effective rpm range of the turbo up in the rpm band. And that will almost always result in higher cruising egts while loaded. Yes, more fuel can spool a turbo faster, but that's not practical when towing at mid throttle. My stock HX35/12 keeps towing egts much better under control than my Hybrid/14 (as in 100-200 degrees cooler and passes/pulls hills without downshifting). But if I'm playing around empty, the Hybrid easily outperforms the stocker on top.



IMO, if you're gonna tow, keep it tight. Or get twins... .

 

[darkhorse]

I'm running a DZ/14. it has a 61mm compressor wheel. The exhaust housing & OE exhaust manifold were ported per hdm48's instructions. Frankly I don't notice it spooling slower than my original HX35/12 but it sure pumps more air when I lean on the go pedal. I was told it would run a little hotter at cruise but in fact, it's been a little cooler. I don't know why but that's what my pyrometer says.

 

[PC12Driver]

Is it running cooler empty or with a trailer? Mine runs about 50* cooler empty with the DZ, but hotter under a load.

 

[darkhorse]

definitely cooler empty. I only tow about 5-7K & since the trailer has horses in it I baby that load. Under those conditions my towing temps. are not much different than with the OE spinner.

 

[BSKI]

I think I am dumping everything listed in my first post and have setteld on the HTBG. The price is right and the upgrade progam suites me well in the event I go bigger. I called HTT and they say most people cant tell the Diff between a 12cm housing and a 14cm housing. I dont know as i have never felt the diff before. Any one out there with some expierance with HTBG with the 12 and 14 CM Housings?

 

[PC12Driver]

Clmsnow just went through this recently with his truck. Check these threads out:



This one is a bit lengthy but debunks some misconceptions. Results toward the end.



And this one is pretty much a summary of his results.