headers? better ideas anyone?

[97GMC]

Well im looking for more performance out of my 97 5.7L GMC truck.

I dont want to get any ECU programs like westers becuase I wouldnt want to run higher octance, not with gas prices like they are. So far, all of my mods have given me better gas mileage as well as more power, and id like to stick with that trend.

The mods are:
AEM (4.5'') intake with heat sheild.
capped intake resonator.
ported and mirror polished TB.
Dual 2.5'' exhuast into flowmaster 40's.
O2 Sims with straight 2.5'' test pipes for cats.

The truck is pretty quick and gets great gas mileage (I broke 20mpg on the highway) but I would like more power. So far im leaning towards headers, but if anyone has a fantastic idea, im open to suggestions.

I wouldnt be opposed to a fuel tuning program tha allows me to optimize the trucks A/F ratio's without a hit on gas mileage, but I dont know of any programs that are user/dyno tunable.

[rjwms]

How about electric fans and/or underdive pullys?

[some1else]

Originally posted by rjwms
How about electric fans and/or underdive pullys?

I've read about people having good results with underdrive pulleys I don't think the gain you'll see with fans will be worth is unless you go the junkyard/ebay route.

I do like those flex-a-lite fullsize truck fans 5600 cfm.. mmmm

I say with no cats, go with some long tubes. You won't see much gain from shorties.

[truckin92pu]

Well if you go with pulleys beware of charging problems at idle if you change the alternator pulley. i would go with headers if i were you or maybe a computer programer.

[97GMC]

I completly forgot about underdrive pulleys. Im not worried about charging issues at idle. I spend myabe 5 minutes a day at idle, the rest of the time its to and from work (highway). Not to mention its really only a major issue if you have a blangin' stereo. I dont. Its all factory.

I wonder if larger ground wires would help. I know they at least smooth out the poewr delivery and idle, but I havent heard anything on whether they actually gain power.

[wm-webb]

I had underdrive pulleys on a truck and hated the lights dimming down at stop lights. The shorty headers and cat back exhaust really helped it out and it sounded:head:

[96ImpSS]

The best thing I did for driving enjoyment on mine was the Transgo shift kit. I had to get the torque management programmed out, but as I understand it, that won't be an issue for a '97.
Next best thing was the headers. I have the headpipes y'd into a single 3"; since you're running true duals, I'd recommend an H-pipe or some type of crossover as far forward as you can get it.

[va454ss]

Electric fans and underdrive pulleys.

Get the Power and Amp series from March. I don't have charging issues at idle.

The fans and pulleys netted me .3 reduction in 1/4 mile ET.:head:

[1996Silverado]

elect fans allowed my motor to rev more freely and made a difference, cost out the door was about $170. contrary to long tube die hards, my shorty headers definately made a difference on the bottom of the RPM range which is where you need it.

can't say anyting about pulleys, never used them.

[1 BAD BURB]

i would have to say that the fans are ur best bet!!! u'll be surprised how much power they free up! i changed mine and immediately i noticed a difference. i can't tell u mileage b/c my regulator was leakin for a long time, i finally got it fixed, but i know for a fact, mileage will go up a lot! 3-4mpg at least! as far as a pulley, im not too sure about that. i also have heard about chargin issues... but march does make a well engineered kit to prevent from low V at idle. again, i have no first hand experience on this, soo u gotta listen to what others say...

also, with headers, don't waste ur time with shorties. u'll want the mid length or long tubes. i have thorleys and i love them!!! this is a mid length, basically the same as long tube. but u'll really like the long tubes as far as exhaust noise and power increase. the exhaust will get a lot deeper and really grumble!!! thats why i love mine!

other great brands, Arizona Speed and Marine (ASM), The Other Guys (TOG), Hooker.

do a search, u'll find a lot!
Aj

[Otto]

do elec fans lower noise in the engine compartment alot???

[1 BAD BURB]

yea, they lower the noise greatly in the engine bay!!! and the fans sound a lot cooler than the stock clutch fan!!! definitly worth it, go for it!!!
Aj

[97GMC]

where can I find fans for cheap? And how hard is the install?

If I can get them for 170 like someone said, It would be a great deal. Much cheaper than headers, and it would keep the car running cooler on the highway (thats all I drive, basically. I live out in BFE)

Thanks for all the suggestions and testomonials. Keep 'em coming!

[no2guncntrl]

Ck out the 280. It might be the setup
that fits yer needs..They ain't cheap.
Summit has em..If ya want some cheap
power, put it on the bottle. You can get
kits that'll be a nice bolt on with safety
built in so you don't blow the eng..
Anyway..
http://www.flex-a-lite.com/auto/html/monster-electric.html
http://store.summitracing.com/partdetail.asp?part=FLX-280&N=120%204294924500%204294924499%20305597

[TXvortec350]

I got the Perma cool 14ich universal fans (I got 2 of them) and each one pulls 2950CFM a piece.They only run 85.00 a piece at summitracing.I would look into those if I was you.They are great fans and really work.If you want to spend some money then go with the flex a lites.

[va454ss]

X pipe (if possible) or H pipe.

More power, less noise:D

[TINY'S97]

haven't done it yet, but heard nothing but good about the fan swap. if charging is a problem check ASP Racing they sell just a crank pulley, @ 70 for steel 80 for aluminum

[no2guncntrl]

I agree with FordSmoker. The Perma's
really do pull some serious o2.
Here's a simple wiring diag that was
posted by a guy at another forum..
You can use it for two fans as it was
drawn up for the Ford Taurus two speed
fan..You can modify it the way you want
or if ya go with the Flexi's, it's all done
for ya just about.. Anway
Ck it out..
http://pic14.picturetrail.com/VOL544/713502/1204867/61024838.jpg

[1 BAD BURB]

well, i would search ebay for cheaper fans. also, i think u might be abe to pull them from a junkyard. the old f-bodies used to use elec fans. im not sure on what sizing though. persoanlly, soo far, i love my flex's... everything is given to ya in a kit! simply rip out the old stuff and throw in the new! the hardest part is to get the stock clutch fan out! after that, its pretty much str8 forward!
Aj

[Merc82]

which are better perma cool or flexalite?