Author Topic: Performance Improvements  (Read 255 times)

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Offline crossboss

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Performance Improvements
« on: September 15, 2018, 11:02:24 am »
Boys,
What single change/modification improved the performance on your stock/near stock CJ?
<My old C.J. heap  aka  S-B Racing!
Current lifelong project: 1969 Mustang Fastback/FOX chassis, Powered by a modern Can-Am 494 (Boss 429), Kaase headed, Autolite 1425 cfm 'B' Inline mounted carb, 5 speed, 4 wheel discs, ala Trans-Am style--Whew!

Offline gregb

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Re: Performance Improvements
« Reply #1 on: September 15, 2018, 11:32:48 am »
Headers........

Offline RoyceP

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Re: Performance Improvements
« Reply #2 on: September 15, 2018, 11:42:13 am »
Detroit Locker

Boys,
What single change/modification improved the performance on your stock/near stock CJ?
1910 Model T Ford Touring Red
1915 Model T Ford Touring Black
1914 Model T Ford Touring
1917 Model T Ford Torpedo Green
1968 Mercury Cougar XR-7 GT-E Green 427 W Code
1968 Mercury Cougar XR-7 428CJ R code 3.91 C6

Offline Bic69scj

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Re: Performance Improvements
« Reply #3 on: September 15, 2018, 12:04:18 pm »
Without a doubt ..... headers.
Dave Bickler

Original owner of a 69 SCJ Mach 1

Offline LightWtJet

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Re: Performance Improvements
« Reply #4 on: September 15, 2018, 12:21:20 pm »
Headers by themselves?  With or without exhaust system / and a carb jetting change? Elapsed time improvement? Thanks
68 White Fastback- Body work done

Offline rockhouse66

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Re: Performance Improvements
« Reply #5 on: September 15, 2018, 12:59:48 pm »
I agree it is headers and preferably in combination with a 1970 style exhaust rather than the crossflow muffler used in 1969.
Jim

'69 Grande CJ

Offline geraldt52

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Re: Performance Improvements
« Reply #6 on: September 15, 2018, 02:30:43 pm »
Match the gears and tires for the intended purpose.  Then headers.

If you're going to run them open, headers have a tremendous benefit, closed through stock exhaust less so.  On anything other than a big block shock tower Ford product headers are a no brainer, but they would no longer be worth it for me on a CJ Mustang...too much hassle if not seriously racing.  The CJ manifolds are pretty good,  and I'd probably go with one of the 2-1/2" engineered X-pipe systems if original didn't matter.

Then off to the chassis dyno for fine tuning.

Offline Chris Teeling

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Re: Performance Improvements
« Reply #7 on: September 15, 2018, 08:03:20 pm »
Timing advance.

With good fuel, 40+ degrees makes a huge difference.
1968 1/2 Fastback
1988 LX 5.0 Hatchback

Offline 428 CJ hardtops

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Re: Performance Improvements
« Reply #8 on: September 15, 2018, 08:41:10 pm »
That's the cheapest . A CJ with 34 degrees is a mutt . Gear is next if you have a 3.00 -3.25 or 3.50 .Good exhaust is vital . They can run real strong with manifolds . My engine came off a reliable not a happy dyno and made 475 at 5900 with manifolds before the valve springs started floating the valves at 6000 . It was still gaining 6.2 hp per 100 rpm between 5800 tp 5900 rpm . With better springs and light racing oil at 6300 it should be pushing 500 hp through the manifolds .
had many 428 CJ and SCJ cars over the last 30 years.I currently own a 68 1/2 coupe and a 69 R code SCJ Coupe and a 70 R code SCJ Cougar Eliminator .I am looking for a 70 428 coupe if anybody knows of one for sale.

Offline 70cj428

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Re: Performance Improvements
« Reply #9 on: September 15, 2018, 11:30:35 pm »
Old School :

Distributer recurve ( 38 total, all in by 2500-3000) , then headers, then gears, then a modern custom ground cam …..


New school:

Giant Fart pipe exaust tips, then NOSSSSSSS    :o :o :o :o :o :o :o