KAyers

I sold my 2002 awhile back due to a divorce and needing to free up some cash. I had to drive a gasser for a few months.

But, a few days ago I bought a 1st gen reg cab 3/4 ton automatic truck. It's kind of beat, but I paid 2000 dollars and it gets 23 mpg, so I'm real happy. I'm excited to not own a truck with an electric lift pump or VP44 pump. I plan to do a good bit of towing with this truck. Max trailer weight will be about 7500 pounds.

This truck is an auto trans, and that leads to my questions....mods and this trans

I'm doing gauges first. Isspro trans temp, boost, and pre-turbo pyro.

Then, I'll do the 3200 spring and tweak the pump a bit. I'm going to go easy on the pump tweaks though as I want good mileage.

I figure I'll add a large fan-cooled trans cooler under the bed like some factory 1st gens had. The trans seems quite healthy so far and I'd rather delay expensive torque converters and valve body swaps for awhile if I can.

Will my trans tolerate the pump tweaks and 3200 spring assuming it's healthy now?

Another question. I understand this truck has an 18 cm turbo housing. Is it worth changing to the 16 cm housing? Is that minor of size difference worth the money and trouble to swap housings?

I appreciate everyone's input and hope I didn't ramble too much.

Kevin

Ilikebikes

If you do minor pump mods (IE not maxing out your pump) then you'd probably be fine. Check to make sure that you're getting full travel on the throttle level and adjust the TV cable to make sure you're getting all you can to the ground for now.

I wouldn't bother with the 16. Get yourself a 12 off a 2nd gen and put that on. You'll love the 12 with just a tweaked pump and stock injectors - I ran it like this for a few months. Spools WAY fast and the whistle at idle is awesome ! I have a 16 on mine now, and it's way laggy compared to the 12. With the pump mods and a 12, it'll feel like a new truck.

KAyers

Thanks for your response.

As far as the turbo housing goes, will I still be able to tow easily in 110 degree Texas heat without the 12cm housing causing my EGT go too high under load? I thought I had read that the small housing may spool quick, but it does contribute to elevated EGT's compared to a larger housing in similar conditions.

I guess I was spoiled by the 2002 in my sig. With the HO, 6 speed and fuel box, the truck pulled very, very well. I hope this truck winds up pulling as nicely as that one did. I never had EGT issues with that truck. I couldn't load it hard enough to heat it up no matter what.

Ilikebikes

These older trucks have much smaller cooling systems than the new ones. I don't really tow with mine, and if I did, the weather here isn't 110*. As long as you keep your eyes on the gauge, it should be fine.

If you're worried about a 12 being too hot, then go for a 14. If you just keep the stock injectors with only mild pump tweaks, I think you'd be ok. IMO going from a 18 to a 16 wouldn't be enough of a difference to be worth the time and money.

G1625S

What speeds do you plan to tow at? The 18 is not a bad housing for an auto-equipped truck, but if you're around town a lot, the 12 will definitely make things more fun. If the truck will be doing double duty as a daily driver and you're only pulling up to 8k, a 12cm may not be a bad idea...still, the 18 is fine with the auto and stock injectors. While it's true your properly-valved truck will not breathe as well as your previous rig, I think you'll be satisfied with the tow-a-bility of the new ride

BigWaylon

I regularly tow ~6,000-6,500 lbs...

it towed 75MPH uphill when it was bone stock...I would've hoped the EGT's were in check, but I didn't have a gauge until after I did some mods...

it probably would've run even faster (not sure why you'd do that) if I had adjusted the throttle linkage...I didn't do that until after some mods...

Greg

johnny5.9

Why would going to a smaller housing raise egt's? True, the smaller housing will increase backpressure but I thought that putting a smaller housing on increased boost levels which would lower egt's.

flashgordon

Hmmm, let me see if i can explain this .......if the back pressure is higher then the boost pressure then the syliner will be filled, paisley, with both ex. gass,(hot) and boost charged air, (warm) causing evan hire sylliner temp as the fuel is burned in the syl. and causing the gass or hot air leaving the eng to rise evan higher....tell you let off of the go peddle!
this could also be vary hard on the turbo causing it to snap the shaft in the turbo