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Pickup Truck

Sun Mar 18, 2001 12:33 am

I've got a 1988 GMC 1/2 Ton 4X4 that I've been tinkering with for a while. I've put a new engine and transmission in it and it's in the bodyshop getting some dings taken out of it and painted. I'm looking for some information on aftermarket computer power chips for the engine. Do any of you have any recommendations for me or know of any websites that I could visit and ask some questions from people who know. I've checked out 2 or 3 of the chip manufactor's sites and of course, their own chip is "the world's best performance chip - guaranteed to out perform all others."
 
NKP S2
Posts: 1665
Joined: Mon Dec 20, 1999 3:16 am

RE: Pickup Truck

Sun Mar 18, 2001 2:05 am

A few questions first: What size/year engine? Is the engine stock? What mods, if any? What are your camshaft specs? In my experience, a new program ( whether installing a "chip", or "burning" a new program in ) will have a negligable effect on a stock, normally aspirated engine's power output...A small increase that will probably not be apparent from a "seat of the pants" perspective. ----- That's only part of the story though: Depending on what kind of authority the ECM has over the drivetrain there are other benefits though that can imrove driveability;...Transmission shift points..rev limiter setting..advance curve etc.. If it's a dead stock '88 350, the engine isn't really flowing enough air/fuel for the stock ECM to be a limiting factor, so I would spend my $$$ on free flowing exhausts and less restrictive air filter assys. Now If you're running a longer duration camshaft you'll NEED a better ECM program. Hope this helps.
 
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RE: Pickup Truck

Sun Mar 18, 2001 4:43 am

Thanks for the reply. It's a brand new factory engine - dead stock with a 4sp OD auto transmission. I've already added the free-flowing exhausts and a K&N airfilter to get it breathing easier. I live in southern Oregon at 4100' MSL and all I'm really looking for is a bit more power to handle pulling a 2000 pound boat and trailer up some of our mountain passes. Is it going to be worth spending the $150 of so for the chip? What about the 160 degree thermostat that some of the chip companies pitch. Thanks again for your help.
 
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RE: Pickup Truck

Sun Mar 18, 2001 5:27 am

Oops, forgot to mention that it is a stock 5.7L 350 CI V8.
 
desertjets
Posts: 7570
Joined: Fri Feb 18, 2000 3:12 pm

RE: Pickup Truck

Sun Mar 18, 2001 5:45 am

I assume that the engine is fuel-injected and not carberated.

the amount of horsepower completely depends on how much money you want to spend, and of course how much of the work you can do yourself before paying somebody else to do it. With the airfilter did you just replace the stock filter or did you go with the full "Filtercharger" package which replaces the stock airbox and a few other components. You have started off in the right direction. Try watching the Sunday afternoon car shows on TNT, while they have a lot more money to burn than the average backyard tuner they do have lots of ideas.

Since you have a new GM crate motor you did miss an opportunity, but you could still do this. You could have had the old engine rebuilt using higher performance products... cam, lifters, valves, valve springs, crank, the whole kit and kaboddle. But then that does eat up a lot of money.

Getting the chip may be the cheapest option you have. I would make sure that it is somewhat programmable and has control over the ECM and the tranny as well. You may also want to upgrade the stock ignition system as well.

You could also replace the differential with something more appropriate to your application too. but again $$$$.
Stop drop and roll will not save you in hell. --- seen on a church marque in rural Virginia
 
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RE: Pickup Truck

Sun Mar 18, 2001 8:35 am

Thank you. I appreciate your help!
 
NKP S2
Posts: 1665
Joined: Mon Dec 20, 1999 3:16 am

RE: Pickup Truck

Sun Mar 18, 2001 2:02 pm

GM "crate" engines vary from mild to wild. It's difficult to draw the line just at which point the stock ECM is limiting output. Cylinder heads and cam are the deciding factor here: Unless the cam is hot to the degree it gives the tell-tale "rump-a-rump" the stock ECM won't be tripped up by any loss of low rpm vacuum...indeed, the computer will "learn" to deal with the increased flow...to a point. If your engine is mildly cammed and the free flow exhaust and the freer flowing intake are your best performance dollar spent. As Desertjets said, try to locate an aftermarket air inlet system...The stock air filter box and ducting are quite restrictive. K&N, Edelbrock, and Mr Gasket as well as others all make these systems. I now on the more modern ECMs and PCMs ( later version of GM powertrain control module ) new chips and re-programmers run 300-400 dollars...and I have yet to see signifigant gains in seat of the pants power_On a stock/mild engie_. If you can snag one for 150 bucks it makes it more worth your while...as small changes of your advance curve, shift points and such will help drivability and maybe add a few ponies as well...and 150 dollars is quite reasonable IMO. BTW, the 160 T-stat is not a bad idea regardless what route you may take...What's nice though is that a cooler running engine will be less likely to detonate...this will allow a more aggressive spark advance which will increase power--if not absolute output, a broader powerband. Remember the adage: Horsepower sells cars..Torque wins races. Best of luck.
 
Superfly
Posts: 37735
Joined: Thu May 11, 2000 8:01 am

RE: Pickup Truck

Sun Mar 18, 2001 2:58 pm

Do you want more torque for pulling power or do you want to race this truck?
GM makes a pretty good diesel engine that has more torque than the 454" cu engine. You can pull a house with the GM 6.2 or 6.5 diesels.
Now if you want to race, I know the 350 can haul ass!
Put in high performance electronic ignition, map sensor, and HP fuel injectors. That's if it's an EFI engine.

Carburetor, 4bbl, dual exhaust (No catalytic Converters) is all you need.

 Smile
Bring back the Concorde
 
Guest

RE: Pickup Truck

Sun Mar 18, 2001 4:28 pm

This is great information. All I'm really looking to do is for my truck to be able to pull my boat up some of the mountain passes around here with a little more enthuasium. Right now I've done some exhaust work and got a K&N filter. I'm thinking of a Hypertech chip with a 160 degree t-stat. Any better ideas? Thanks again!!!
 
desertjets
Posts: 7570
Joined: Fri Feb 18, 2000 3:12 pm

RE: Pickup Truck

Mon Mar 19, 2001 9:03 am

One last thing... but this could also be pricey.

You should make sure you have an appropriate rear differential for what you are doing. The stock one may not be suited to yanking a trailer. But just pulling a 2,000 lb trailer with a slightly modified 350 should be more than adequate. Just getting it to breath better will make a marked difference.

BTW, where in Oregon are you?
Stop drop and roll will not save you in hell. --- seen on a church marque in rural Virginia
 
Guest

RE: Pickup Truck

Mon Mar 19, 2001 12:33 pm

Klamath Falls

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