Turbo Advice

[turbo84voyager]

About 2 years ago I helped a friend put a cummins from a wrecked 91.5 D250 in his 92 Ford F150 4x4 short box. The cummins has the Holset H1C turbo ( no wastegate). The truck runs great but the turbo is very laggy. The most boost he can make is about 10 psi. He would like to replace the turbo with something that will spool faster. He is not looking to make more power, just less lag. There is no comparison between this and another friends 94 dodge 2500 which must have a smaller turbo ( has a wastegate). This spools much faster and makes 20+ psi of boost. Both are 12 valve engine and the only difference is the 94 has the newer style pump. The problem he has is the worst when towing something when he shifts gears, it's slow to build boost and there are a lot of hills in our area. When towing ( not heavy loads) EGT's are around 1,150. Does anyone have any advice as to what turbo he should get?

Below are the specs on the truck:

92 Ford F150 4x4 short box (was gas 300)
91.5 Cummins 5.9 (Intercooled version) using a hybrid 300/cummins mounts I fabed.
Dodge Intercooler
Ford ZF (gas big block) 5spd with Destroked adapter - This is not the close ratio version that the Powerstroke uses but the gear spacing is not enough where I would expect to have any major problems. Others have used this without problems.
3.55 Gears -- Started with 3.08 gears but lag aweful
3" exhaust with no muffler or cat


He does not want to make big HP numbers because he is concerned about breaking something. He just wants less lag. Pretty much everything we have found online are for performance upgrades. He already cracked the stock ford 8.8 rear carrier in half ( was quite impressive) he now has a much stronger differential.

Thanks,

Justin

[RoadWarrior222]

Somethings up, that should be a pretty good size for spool... check this post though.>> http://www.cumminsforum.com/forum/94-98-powertrain/435731-holset-h1c.html#post4494565

[turbo84voyager]

Thats what confuses me, guys can spool them with 4 cylinder gas engines but it struggles on a 360 CI diesel??? It appears there have been different exhaust housings. His has I believe the large 20cm housing. I wonder if a 16cm housing with a fuel pin would work.

[shackwrrr]

I'm sure it has the 22cm lag master h1c. There is a thread around here somewhere about swapping it out

[turbovanman²]

HE351 or HE341. 351 is the HX35 with a smaller turbine a/r, 341 is same a/r but slightly smaller.

[dixiedodge7369]

You gotta remember that engine only made 160 hp maybe some fuel pin mods and such might improve the lag... My 06 has he351 stock and it spools pretty quick and pulls almost 40psi stock... Those 12 valves can make some good drive able power... Mines 325hp stock and its not overbearing or super fast..

[440dart]

You can pick up an he351 for pretty cheap most 12v guys on a budget swap there stock turbo out for the he351 wich is the stock turbo on the 04.5-07.5 its going to be the best performaning stock turbo. Drill out the wastegate to almost the same size as the wastegate puck dont run any boost to the wastegate can let drive pressure force it open.

[94GTC]

Pretty shure I have a 12cm housing, "new" collecting dust. My 92 had a 21cm housing stock, and I put on a non wastegated 16cm housing, screwed in the afc and turned the psi up a little and it made a huge gain in response and power.

[Vigo]

Ive driven a 91 or 92 cummins with that turbine housing and it totally ruins the truck. Seems to me you just need a turbine housing swap.

[turbovanman²]

21cm housing, great if you like lag, :confused: :p

[Vigo]

Or the second turbo on a compound setup.... *crickets*

[82F100SWB]

Yes, that truck has a lagmaster exhaust housing. My 92.5 with it's 18.5cm housing is MUCH better. Without a wastegate on mine there is no way I would go smaller than the 18.5, the egt's skyrocket past 2800 rpm and I have 35 psi right now.

[94GTC]

Mine never ran hot with the 16cm housing, but I never went that high of psi with it either. An He 341 would be ideal for what he is doing. It would spool quickly, and hve more than enough air for a stock/ mildly fueled early engine. Enlarging the waiste gate passage is always a good thing, though not needed for his application.

[The Pope]

I have the 40 hp marine injectors, K&N, turbo back 4" diamond eye, all the fuel pin safe gaurds removed and the pin ran in till it bottoms, star wheel to the top, custom ground fuel pin, timing leaving the pump 1/8" off the engine, idle screw pulled back a hair over 1/8", and a 16cm housing.

The big thing is not turning the star wheel down too far with the fuel pin. Turning up the screw all the way in gives up the raging mileage, I was getting 28 with stock exhaust and just went to 4". Really helps temps but you don't feel that much power as that comes from fuel. The intercooled trucks got a smaller injector, the early non intercooled trucks don't need an injector swap for a while.

A local here builds the custom converters, a must with a shift kit for the auto trucks. Otherwise it'll hit boost giving a jump off the line then nothing really. The trans shifts too late and the fuel shuts off before you get to shift point stock. The fuel screw deals with that and the all important 3200 RPM fuel spring needs to be there. I also did a head gasket and more bolt torque, had a valve job done and I mildly ported the head. I run the star wheel in just a turn or more, to get just a light haze out back under boost. If the star wheel is down and you get a big black clowd your not moving enough air and it'll get hot fast. Without maxing the fuel screw you get poor mileage, the lower pressure doesn't atomize the fuel as well. I tunred my all the way down for emissions and there was no power and 16 MPG..

[mopardad1]

We swapped the exhaust side on our 93 4.10 geared 2wd from a 21 cm to a 16 cm and saw a definite increase in spool speed.
It had a slightly noticable lag with the 21, but it would keep boosting till you ran out of fuel, well almost, but it produced well over 20 pounds of boost.
The only modifications are a) no muffler, b) cold air intake. We have since added a custom downpipe, 3 inches out of the turbo, immediately belling to 4 inches going staight down then to 5 inches under the passenger floorboard exiting just in front of the passenger side dual wheels.

[Vigo]

I think in your case the 21cm housing was being band-aided by 4.10 gears. That housing absolutely sucks in the taller geared trucks ive driven.

[mopardad1]

Yeah, I could spank a 5.0 Mustang.....across the intersection!

[moparzrule]

As others said, thats a 21cm housing on the Holset H1c turbo. Starting in 94' they went to the 12cm housing on the H1c and then it was called the WH1C. But in 95 they started using the HX35W. You really want a 95-02 turbo as in 03-newer they started using a 4'' V band turbo and also the compressor housing has a 90 degree bend instead of straight outlet.

Also in around 99-00 they went to an 3'' cast exhaust elbow coming off the turbo instead of the 3'' V band outlet. So ideally you want a 95-98 turbo.

This turbo right here would be direct bolt on replacement for an H1C-

http://www.ebay.com/itm/Dodge-Ram-Cummins-Holset-Turbo-HX-35w-Turbocharger-/321064357052?pt=Motors_Car_Truck_Parts_Accessories&hash=item4ac0ed4cbc&vxp=mtr

[turbo84voyager]

We replaced the housing with an aftermarket 16CM housing. What a difference. Thanks for the info everyone!