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I have found a used polymer intake for sale. The asking price is $200. Comp cams catalog says the intake will weigh 16 lbs less than the stock. Will this intake have a flat torque curve? Is this intake worth considering? Thanks guys for your help.

David
 

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I am using a Hartman PowerBox upper intake on a stock lower. This is the same intake as the Comp Cams as they bought out Hartman 2-3 years ago. My engine is a stock '89 5.0 with MAC 1 5/8" headers, 65 mm throttle body, no smog pump, and standard rotation waterpump with no idler. There is no lack of low end power as some people suggest. With the stock 2.73 rear gear, I can spin the tires at any speed in 1st gear and have little traction in 2nd and the engine pulls to 5500-5600 rpm.
The main reason I bought it was to clean up the looks of the engine. I think that $200 is high. I just found the receipt for mine, $130 including shipping.

Chris :cool:
 

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I can't help you on the performance issue. Because mine is for the next Cobra I build.
But I can chime in on the price. I have the one that matches the GT-40 lower and I piched it up for $140 shipped. E-bay usually has them for sale, or check the Corral.net

Brad

 

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On nearly every dyno test everywhere on the planet they lose power to a "long runner" style intake except at over 6000 RPM in NA form.

They do well on power adder cars. (Turbo / SC)

I asked several good shops about going with a box upper. They all said don't do it...and I have a SC.
 

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David,
As you may have read or heard in the past, it's all in the combination. I'm not sure, but I assume you have a fairly stock 5.0 engine.

Box style intakes like the Comp and Hartman generally improve power above 5000rpm over stock, long runner style intakes. Box uppers are designed for high RPM engine combinations. On a stock engine, with stock heads and cam, this intake would certainly make less power than the stock upper intake below that rpm. Unless you have the rest of your setup optimized for it, you will make less average power, and a little more peak power at the expense of much less torque and midrange. The engine would probably feel "peaky". The car would be comparitively slower in the quarter mile.

With better heads, more gear, and the right cam, this intake would work much better.

Check out the November issue of 5.0 Mustang and Super Fords magazine. There's an article comparing six high rpm intakes( two are box style ) at Anderson Ford Motorsports on an 8000rpm small block. The motor is a DSS 347 with an AFM N113, High Rev camshaft, and Stage V ported, Trick Flow, Twisted Wedge heads. Not exactly stock!
 

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How long are the runners in the Comp box-type upper? Are they really short? The reason I ask is I'm trying to build a custom upper intake. I can easily get the runners in the upper to 4" or more. Would this be long enough to keep the low end power from dropping off too much?

Greg
 

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What I'm talking about is the section between the box and the lower intake on the Comp. How long are those? Just trying to get an idea of how long I need to make the runners in my intake to keep the performance respectable. I'm not saying my intake will have a box on top of 6" runners, but I'd like to know if I need to work on getting my runners longer to keep the power up. I guess what I'm trying to say is: what is the minumum runner length I should shoot for. Sorry about the confussion.

Greg


[ December 29, 2002, 12:51 PM: Message edited by: GregR ]
 

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Discussion Starter #9
Thanks for the info guys. The price is too high, and I dont plan to run over 5000 rpm, so I have already forgot about it.
 

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Without using a string and a measuring tape I believe they need to be 11" to 13" long.
 

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The runners on the Comp. Box upper are about three inches long.

Brad

 
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