Engine/Transmission (1994 - 1998) help me bomb a twelve

[mgoncalves]

Okay guys, I've tried searching and cannot find the idiot's guide to turning up a twelve valve, so please help me out a little.



The truck is a stock 94 4x4 auto, the guy bought it for a steal and wants more power, but doesn't want to upgrade anything (trans) until it's not working.



I've told him he needs gauges and exhaust but, he still wants more power first.



So, how do I turn it up?? I am somewhat familiar with the first gen pumps (just turned up my dads last weekend ) but don't know where to start with the P-pump. Any tips are appreciated.



Thanks

Matt

 

[SEmerson]

Just sliding the plate will help alot. and it is free. You can buy a more agresive plate and reajust the lever. Also bump up the timing but for this you need tools. How much does he want to spend?

 

[Deezul1]

Turning it up without an EGT gauge is asking for burnt pistons. If you cant afford a gauge you sure cant afford a engine rebuild. Moving the plate forward helps but adjusting the AFC star wheel to the farthest forward position will make a difference without too much chance of burning something up. The star wheel is under the plug on top of the injection pump at the rear and takes a large ALLEN wrench to remove.

 

[mgoncalves]

Originally posted by Deezul1

Turning it up without an EGT gauge is asking for burnt pistons. If you cant afford a gauge you sure cant afford a engine rebuild. .

I've tried to tell him that. It's not that he can't afford the stuff, he just has a don't fix it until it's broke mindset.



Which way do I move the starwheel??



Matt

 

[Deezul1]

Turn it so the spring is relaxed rather than compressed which is towards the front of the truck

 

[SEmerson]

forward for more fuel sooner. It is true if he tows full pedel he will proble burn a piston.

 

[R.ebel]

More Power

Hey Matt, be sure to slid the AFC housing all the forward. Not a huge increase but it will help in the quest for more power. Also if you slid the plate forward get a boost elbow. A stock 94 automatic will start having problems around 240-250 hp. I would also consider some govenor springs. The stock govenor springs in the early P7100's really pull off the fuel pretty aggressivly around 2400-2500 rpm.

 

[98rammer]

without a gsk, you should definately NOT be getting into the danger zone. when i had my 180 pump, intake, exhaust, disabled wastegate, and a #0 plate (no gsk, injectors, etc. ), i was hard pressed to hit #1150*.



with the stock plate slid forward i'd say that he'll only be hitting around 900* maybe 1000*-1100* with the stock exhaust/intake... as along as the transmission can hold it (or you know how to drive it right without slipping it). the gsk is far better for driving, but it simply depends on what you want.



Tom

 

[SMorneau]

Save the diesels!

You should probably tell him the gauges are the first step, Period. They are needed for safety as well as tuning the performance of the truck. If you are his advisor he should take your advice.



These forums are full of real world knowledge on these trucks. It is up to your friend to figure out what he wants from his truck.

 

[Extreme1]

Guages first. Otherwise he will be replacing REAL EXPENSIVE parts that he normally wouldn't have to.



Then I'd do a GSK. With the weak torque converter in the '94 auto, more power won't matter, he won't be getting it to the ground but the GSK will help with a stock trans.



Then it time to play with fuel delivery more agressively. Plate (or, if high milage, remove the pump and send it to PDR for slightly more $), injectors, timing.



Then air flow will be an issue and he'll need bigger exhaust and intake flow. Which parts he selects will be (somewhat) guided by where he wants to end up power-wise.



As for the guages and not removing parts until breakage, if he had a nice early 70's musclecar would he remove the exhaust manifolds to install headers? Would he add temp and oil pressure guages? What are the odds of an oil pump failure compared to EGT damage when you can't tell the temp?

 

[Hammer]

Well I treid to steer clear of this one,BUT....

Matt...

Really I tried but I'll drop a post in for this and await the flaming I'll receive because I know its coming. I disagree with most on the guages being needed and the first thing to be bought. Old wise man once told me this when I was a real young buck and seen his race car at the shop with no guages in it... "If you can not see it from the grandstand or it doest't vibrate your goggles off it is not necessary",that man was none other than the legendary Kenny Weld. Why do I say that above you ask,in the heavy truck market today there are alot more trucks out there hauling alot heavier than we can and are equipped with alot less guages than some here recommend. Most even nowadays do not even use a egt guage and some companies dont even use much more than a speedo,alt guage and air pressure guages. Its his truck and wallet as long as he is willing to accept the consequences for his actions without you having to receive repercussions,let him proceed. One thing on the guage deal I will say,IF,he hauls heavy trailers or tows allot he ought to think about a egt at least.



One thing I'll add as most have already touched base on some minor tune-ups. Make sure he has a fresh service on the truck first for a good baseline. This means all fluids checked or changed as needed-fresh oil & filter,fresh fuel filter,fresh Tran fluid & filter,transfer case fluid changed,change the antifreeze,new air filter and adjust the valves. It sounds like alot and will make him learn that a good baseline is the first step before tuning. He just bought the truck and its used,I am not him I know,but,how many people actually keep the maintenance and proper records for all this,unless the truck was owned by a TDR member,not many. I take no ones word on fluids myself and changed mine all when I bought any of the trucks I own or owned.



Mods and tune-ups are deadly on stock transmissions/converters. Make sure he understands completely what could happen there. I have seen more than one stock converter rattle apart inside along with many wiped out clutch packs and bands. Make him look around at all the diesel boards and see how many have destroyed stock parts with good tune-ups. One last thing and I'll step out and quit being so windy. Explain to him Rome was not built in a day and mods are not all needed as soon as he sits down in the seat. While I do understand the quest for more power,I also understand more research and wiser spending will net better gains or a better bang for his limited bucks. Hope this helps and now I'll don my flame retardant suit... ... ... ... Andy



P. S. -Have him write our saying down from here at least a 100 times on paper so he learns it and completely understands it... ...

"I AM MY OWN WARRANTY STATION"

 

[R.ebel]

Gauges

Originally posted by 98rammer

without a gsk, you should definately NOT be getting into the danger zone. when i had my 180 pump, intake, exhaust, disabled wastegate, and a #0 plate (no gsk, injectors, etc. ), i was hard pressed to hit #1150*.



with the stock plate slid forward i'd say that he'll only be hitting around 900* maybe 1000*-1100* with the stock exhaust/intake... as along as the transmission can hold it (or you know how to drive it right without slipping it). the gsk is far better for driving, but it simply depends on what you want.



Tom

Something is wrong with this picture. When my 97 12 valve was completely factory stock the egt's would go as high as 1250 degrees (pre turbo) in 5th gear near redline. Gauges are a must on any bombed truck, especially so if you tow or haul.



Tom I'm not flaming you, but I have to wonder about the accuracy of your egt gauge. Were these temps post turbo or pre turbo?

 

[Deezul1]

"In the heavy truck market today there are alot more trucks out there hauling alot heavier than we can and are equipped with alot less guages than some here recommend. Most even nowadays do not even use a egt guage and some companies dont even use much more than a speedo,alt guage and air pressure guages. "



Would this be due to computer controlled fueling that is reduced automatically when EGTs are getting to high? This for sure wouldnt apply to a 12 valve with no computer engine controls.

 

[bmoeller]

Originally posted by Deezul1

"In the heavy truck market today there are alot more trucks out there hauling alot heavier than we can and are equipped with alot less guages than some here recommend. Most even nowadays do not even use a egt guage and some companies dont even use much more than a speedo,alt guage and air pressure guages. "



Would this be due to computer controlled fueling that is reduced automatically when EGTs are getting to high? This for sure wouldnt apply to a 12 valve with no computer engine controls.

Even the older mechanical truck engines I've seen/run, most didn't have more than the minimum for gauges. No boost or pyro, let alone engine oil/transmission/axle temp, air spring/load pressure for the air-ride susp. and others.



Personally, I think that boost/pyro. (and transmission on auto) gauges should also be standard OEM epuip. whether it be light or heavy duty useage.

 

[Joseph Donnelly]

Just put in a TST Power Kit, #8 = 210 hp, or #6 = 230 hp. That is about all the transmission will take stock for an extended itme, and egt will remain OK unless the exhaust is very restrictive (e. g. plugged cat).

 

[98rammer]

Re: Gauges

Originally posted by R. ebel

Something is wrong with this picture. When my 97 12 valve was completely factory stock the egt's would go as high as 1250 degrees (pre turbo) in 5th gear near redline. Gauges are a must on any bombed truck, especially so if you tow or haul.



Tom I'm not flaming you, but I have to wonder about the accuracy of your egt gauge. Were these temps post turbo or pre turbo?

that's because you have the 215 pump. they tend to get a lot hotter than the 180 pumps. these were pre turbo. my buddy's stock HO will hit 1300* stock.



tonight i hit a new record of 1750* for a quick second or two



Tom