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L98 Power Numbers

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Old Jul 16, 2013 | 11:53 PM
  #1  
Cole317's Avatar
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L98 Power Numbers

Hi Guys,
I have the chance to buy an '88 350 with ported aluminum l98 heads, gm hot cam kit, carbureted conversion, and dual plane intake manifold. the seller claims this combo will put out a little over 400hp and 400tq. Does this sound about right?
Thanks!
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Old Jul 17, 2013 | 12:18 AM
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Re: L98 Power Numbers

Not even close.

270-290hp and 320-340tq.

Im pulling those numbers out of my bum hole btw.
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Old Jul 17, 2013 | 12:24 AM
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Re: L98 Power Numbers

Then how did you come to those numbers? Thats barely better than stock. I've read articles where people get well over 400hp from this set up and some others say around 350hp. It would be awesome if anyone had this set up or something similar!
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Old Jul 17, 2013 | 12:50 AM
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Re: L98 Power Numbers

I just found this article: http://www.hotrod.com/techarticles/e...n/viewall.html
Stock, using a carb and new intake, they got 329hp and 393tq. This makes the seller's claims seem more realistic.
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Old Jul 17, 2013 | 07:44 AM
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Re: L98 Power Numbers

Originally Posted by LSJuan0068
Not even close.

270-290hp and 320-340tq.

Im pulling those numbers out of my bum hole btw.
At the tires maybe...lol

I saw testing years back of stock L98 aluminum heads vs vortecs and the stock aluminum heads were making 380 hp on an engine that made a littlr over 400 with vortecs. I saw a gm 350 ho 330 hp crate engine run with an airgap intake, quick fuel carb, hedman longtubes, and a LT4 hotcam kit make 401 hp and 428 tq.

Last edited by Fast355; Jul 17, 2013 at 07:47 AM.
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Old Jul 17, 2013 | 08:04 AM
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Re: L98 Power Numbers

The HotRod article #s pretty much pass the smell test, for a well-tuned motor on an engine stand with no accessories and a REALLY GOOD exhaust. They're probably 40 HP high for the same motor installed in a chassis, and about 80 HP higher than it would read at the rear wheels.

400 HP is basically approaching the Outer Limits for those heads, unless the porting job was done by a race shop with a flow bench that could monitor the effectiveness of what they were doing (and had plenty of cores to do-over on when they scrapped one).

As always, the rule for buying used cars or car parts is: never believe one single word out of the mouth of a seller unless you can verify it yourself by independent means. You can tell if they're lying: if their lips are moving, they're lying. You can tell if they're stabbing you in the back: if they're smiling, watch out for the knife. Sad, but that's just The Way It Is.

IN general, I put magazine article #s in the same category as used-car sellers. The purpose of a magazine is NOT to educate or "tell the truth"; it is to ENTERTAIN, and in the process, MAKE MONEY for its publisher by providing a vehicle to SELL ADVERTISING. Just like the used-car seller, once the supplier of "information" has a financial interest in outcomes derived from the "information", all objectivity and trust goes out the window.
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