Increasing HP

Make your Cougar run faster, handle better, and jump higher... okay maybe not jump higher. If you feel the need for speed, this is the place.
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yearby
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Location: Australia

Re: Increasing HP

#21

Post by yearby » 20 Apr 2019, 10:52

Just a cautionary note here, the standard 289/302 Windsor's have very weak con rod bolts, they tend to stretch under high revs, and these engines do love to rev.
I suggest that a cheap alternative to aftermarket rods is to replace the 5/16 rod bolts with the Chevy 3/8 rod bolts. Then have the rod big ends resized, have the rods crack tested, checked for straightness and magnifluxed. Having the rod resized will prevent the bearing spinning in it's bore, safe insurance.
With this done I would push to 6500 rpm with out any problems, but have heard of standard bottom end engines doing in big end bearings at 6000 rpm.
May be worth while to do on a stock rebuild to be on the safe side as well.

If anyone here was going the stroker route, use stronger aftermarket rods.

:)

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yearby
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Re: Increasing HP

#22

Post by yearby » 20 Apr 2019, 10:54

CMCE wrote:
20 Apr 2019, 05:54
If everyone doesn't already know, Pypes has stepped up to the plate and developed a 2.5" X-Pipe exhaust system specifically for the '67-'70 Cougar.
Check it out- https://classicmusclecarexhaust.com/c/q ... ugar/pypes
Would like to know what cabin noise is like with these? Anyone?

canted 393
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Location: New Hampton IA

Re: Increasing HP

#23

Post by canted 393 » 20 Apr 2019, 11:13

Yearby I have this kit on my 73 stang with a 525 hp 393C and my answer is no its loud out back but not inside. But I did go with the violator muffler option which is a strait thru design. Its nice kit and living in the Midwest where everything rusts to the ground because humidity or anything that had been driven in the winter the stainless is nice.
Last edited by canted 393 on 20 Apr 2019, 11:28, edited 1 time in total.

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yearby
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Re: Increasing HP

#24

Post by yearby » 20 Apr 2019, 11:27

Thanks :)

Steve68Cougar
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Location: Manhattan, KS

Re: Increasing HP

#25

Post by Steve68Cougar » 20 Apr 2019, 19:13

yearby wrote:
20 Apr 2019, 10:52
Just a cautionary note here, the standard 289/302 Windsor's have very weak con rod bolts, they tend to stretch under high revs, and these engines do love to rev.
I suggest that a cheap alternative to aftermarket rods is to replace the 5/16 rod bolts with the Chevy 3/8 rod bolts. Then have the rod big ends resized, have the rods crack tested, checked for straightness and magnifluxed. Having the rod resized will prevent the bearing spinning in it's bore, safe insurance.
With this done I would push to 6500 rpm with out any problems, but have heard of standard bottom end engines doing in big end bearings at 6000 rpm.
May be worth while to do on a stock rebuild to be on the safe side as well.

If anyone here was going the stroker route, use stronger aftermarket rods.

:)
Good point on the rods. I went the "easy" route and just replaced the stock 5/16 bolts with ARP rod bolts. It's seen 6000 rpm quite a bit and (so far) has not been an issue. I wouldn't want to push it to 6500-7000 without doing something more extreme like you're suggesting. That's another part of why I didn't go with any more cam than what I did.
68 Cougar -Augusta Green
08 Mustang Bullitt - Dark Highland Green

CMCE
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Joined: 11 Apr 2019, 16:21

Re: Increasing HP

#26

Post by CMCE » 12 May 2019, 17:59

yearby wrote:
20 Apr 2019, 10:54
CMCE wrote:
20 Apr 2019, 05:54
If everyone doesn't already know, Pypes has stepped up to the plate and developed a 2.5" X-Pipe exhaust system specifically for the '67-'70 Cougar.
Check it out- https://classicmusclecarexhaust.com/c/q ... ugar/pypes
Would like to know what cabin noise is like with these? Anyone?
I can tell you from experience that the Race Pro mufflers are pretty quiet at idle and cruise, but being a straight through muffler they'll bark at full throttle. They flow extremely well but the actual sound that comes out will always depend on cam, compression etc. Classic Muscle Car Exhaust has sound clips with most of their systems. https://classicmusclecarexhaust.com/

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bsbeck
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Location: Alabama

Re: Increasing HP

#27

Post by bsbeck » 15 May 2019, 11:11

canted 393, I'd like to hear details on your engine build please. PM me please.
Scott B.

1970 Cougar Eliminator (Competition Blue / Black Comfortweave / 351 Cleveland / Automatic)
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canted 393
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Location: New Hampton IA

Re: Increasing HP

#28

Post by canted 393 » 16 May 2019, 05:29

Scott will do as time permits. Thanks Dan

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