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What's the most cost-effective way to increase LG4 horsepower?

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Old 03-20-2006, 02:00 PM
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What's the most cost-effective way to increase LG4 horsepower?

Hey everybody. I'm new to this forum, and it's quite possible that I will be buying a 1985 Camaro Z28 this Wednesday. Looking at the horsepower numbers for an LG4, I've got a feeling that I'm going to want to get a little more punch out of it. The numbers I've seen say about 155 hp and around 245 ft/lbs of torque. I currently drive a 1999 Toyota Rav4, which produces 125 hp and 130 ft/lbs of torque. The two weights are comparable, with the Camaro weighing about 300 lbs or so heavier (Rav4 is ~2800 lbs). I suppose my first question should be whether or not I'm going to notice the difference in power and torque when I'm driving. What is all that extra torque going to equate to when I'm driving? More pickup? Faster start? Second, what would you suggest I do to increase those horsepower and torque ratings? I'm not going to have a whole lot of money (I'm a poor high school student), so whatever I do has to be well worth what I pay for it. I was thinking about cold air intake (or a 5.0 HO air cleaner assembly, if I could find one), a new exhaust (headers, hi-flow cat, ect., though this would be pricey, I think), and an electric fan (so it doesn't leech my horsepower). Also, what other mods do you think would be worth my while? I know very little about cars, but I want to learn. Let me know what you think!

Thanks,
Frank

P.S. Anything in particular I should look out for when I go to buy it?
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Old 03-20-2006, 03:15 PM
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Re: What's the most cost-effective way to increase LG4 horsepower?

full exhaust and an open intake is a good, economical start. You can get away with full exhaust cheaply enough... hedman shorty's with y pipe is ~$200 at summit. If you don't have emissions, skip the cat. Hooker super competition catback exhaust is around $250. You'd notice huge gains from full exhaust and any kind of free-breathing intake setup. Many will say a 3" K&N and an open element lid is a good plan, but I think your HO lid with a K&N filter would work better.

Other things to think about would be rearend gears. They run around $200, which isn't too expensive, but install can be pricey unless you know someone. A set of 3.73 gears really wake these cars up.

A lot of people will get a nitrous plate kit for it and spray 50-100 shot until the 305 nukes. You could get away with 50 shot for years though, if the motor's strong.
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Old 03-20-2006, 03:37 PM
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Re: What's the most cost-effective way to increase LG4 horsepower?

What would do is save up my money and upgrade to a 350. You can get a 350, 4bolt from GM with 290hp/326ft lbs of torque for under 1700. Thats more power than ever came stock in a 3rd gen F-body. It's a good start, and very upgradeable. Goodluck, Charles
http://www.crateenginedepot.com/stor...29-P824C2.aspx
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Old 03-20-2006, 04:35 PM
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Re: What's the most cost-effective way to increase LG4 horsepower?

nos dawg. exhaust and intake stuff.
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Old 03-20-2006, 09:00 PM
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Re: What's the most cost-effective way to increase LG4 horsepower?

True, that crate engine is a lot of bang-for-the-buck. However, it isn't emissions legal, which is a problem. I didn't realize that exhaust is that cheap, I'll definitely look into that. Thanks for the advice, keep it coming!
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Old 03-20-2006, 09:30 PM
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Re: What's the most cost-effective way to increase LG4 horsepower?

if you want real power get away from the LG4

if you just want a little power exhaust and air intake are your basics,

I'd stay far away from nitrous on a stock motor,
it can be done but its generally not recommended
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Old 03-21-2006, 07:02 AM
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Re: What's the most cost-effective way to increase LG4 horsepower?

you'll notice the increase in torque off the line. the lg4 will run out of steam pretty quick in the rpm band, unlike the other car which probably makes its power higher.

the major downside for the lg4 was the rediculously small cam. step up the cam to something like a used LT1 cam (very cheap), a decent intake manifold, some headers and exhaust and you'll be suprised what the car will do.

it won't blow many doors off...but it will be a nice boost in performance
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Old 03-21-2006, 07:30 AM
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Re: What's the most cost-effective way to increase LG4 horsepower?

other than nitrous a new camshaft will get you the best bang for your buck, you can get a camshaft kit with the cam, lifters and lube for like $130 and itll wake your LG4 up like no other. that mixed and match with anyone else mentioned in this thread will give you very good results
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Old 03-21-2006, 08:26 AM
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Re: What's the most cost-effective way to increase LG4 horsepower?

Originally Posted by teke184
you'll notice the increase in torque off the line. the lg4 will run out of steam pretty quick in the rpm band, unlike the other car which probably makes its power higher.

the major downside for the lg4 was the rediculously small cam. step up the cam to something like a used LT1 cam (very cheap), a decent intake manifold, some headers and exhaust and you'll be suprised what the car will do.

it won't blow many doors off...but it will be a nice boost in performance
LG4 isn't factory hydraulic roller cam
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Old 03-21-2006, 10:45 AM
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Re: What's the most cost-effective way to increase LG4 horsepower?

Full exhaust and an open element aircleaner (3" K&N would be a good choice) will help wake the car up. A mild cam would also help, but I would save that for a little later.

Chances are your car has 2.73 gears, which will really make the car feel sluggish off the line. An ideal situation would be to find a fourth gen rear with 3.42s and also a set of late third gen axles (same width as your axles, but 28 spline instead of 26). Then you could assemble everything in the factory housing and have better gears and a posi (limited slip differential).

- Justin
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Old 03-22-2006, 08:51 AM
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Re: What's the most cost-effective way to increase LG4 horsepower?

Well, for examples sake, here's what i had done to my LG4 to get 230rwhp/270rwtrq (dynojet #'s and SAE corrected)

- NON computer carb/performer intake (the stock stuff will do if you need to adhere to smog)
- Rebuilt set of heads - just had a good valve job, no porting
- Crane compucam 2030 (these are ruff numbers, i dont remembert the exacts) but it was close to 430 lift on both sides, 214/220 dur, 114 lsa... it was around the biggest you could go, still keep the computer happy and emmisions guys happy, and also not have to clearence the pushrod holes...
- Edlebrock 1 5/8 shortie headers
- SLP cat back...

This was through a 5 speed trans... thing ran good, would hold it's own against even minor bolt on lt1 cars... beat the hell out of it all the way to 250k when a valve retainor broke and dropped the valve down...
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Old 03-22-2006, 06:28 PM
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Re: What's the most cost-effective way to increase LG4 horsepower?

89 vert,my 87 lg4 was a factory roller...and i tried giving the block away and noone wanted it so on garbage day i flagged down my local sanford and son garbage picker and he gladly took it for scrap
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Old 03-22-2006, 07:46 PM
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Re: What's the most cost-effective way to increase LG4 horsepower?

Originally Posted by anthony714
89 vert,my 87 lg4 was a factory roller...and i tried giving the block away and noone wanted it so on garbage day i flagged down my local sanford and son garbage picker and he gladly took it for scrap
87 is the only year then, I can say for sure 86 and down isn't roller
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Old 03-22-2006, 10:24 PM
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Re: What's the most cost-effective way to increase LG4 horsepower?

Originally Posted by 89Vert
87 is the only year then, I can say for sure 86 and down isn't roller
When did they start putting roller 350 TPI's in? I beleive it was 87. So it would make sense that an 87 LG4 was roller too. So prolly 87+ were rollers.
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Old 03-23-2006, 12:15 AM
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Re: What's the most cost-effective way to increase LG4 horsepower?

87+ were all roller.
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