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Cost difference when building a 306 vs. 347

  • Thread starter Thread starter 90mustangGT
  • Start date Start date Oct 19, 2004
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04-SVT

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Sep 5, 2004
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Las Vegas, NV
Oct 21, 2004
#21
  • Oct 21, 2004
  • #21
90mustangGT said:
Has anyone heard of C.A.T. products? They have some good prices and a local dealer stocks them.
Click to expand...

I would also recommend you stay away from them. Local shop here in Vegas sells them and he has nothing but bad things to say about their craftsmanship and quality of CAT products.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
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PA
Oct 21, 2004
#22
  • Oct 21, 2004
  • #22
Most of the CAT stuff is very bad....

There are a lot of other companies that buy there stuff and private label it as well, something to be careful about.
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
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Dallas, GA
Oct 21, 2004
#23
  • Oct 21, 2004
  • #23
I wasn't really considering C.A.T., just never heard of it. I was wondering how hood they could be when the 4340 Forged unit was about the same price as most companies cast, and cast 3.4" stroke was something around $120.

I did a compression check on the engine. It got suprisingly even numbers with the compression:

1 - 155
2 - 165
3 - 160
4 - 160
5 - 155
6 - 160
7 - 165
8 - 160

The numbers wern't on the digit because the gauge was in 5psi incriments, but that's all averaging 160psi, two down 5psi, two up 5psi. The test was performed at operating temprature, with all plugs removed, throttle closed, about 10 turns to get peak numbers. It took about 2 - 3 turns of the engine to get over 80psi.

I'll do the leakdown check next when my co-worker brings in the tool, he said that will tell me more.

If the engine does well with the leakdown, should I get another block and build that engine? I'd hate to tear down a good motor, it could be put in something else.
 

RydeOn

Licensed to Chill
Founding Member
Sep 26, 2000
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Oct 21, 2004
#24
  • Oct 21, 2004
  • #24
347 it 90mustangGT!! You know u want to!
 
9

9 Deuce GT

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Dec 10, 2003
550
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Geneva, NY
Oct 22, 2004
#25
  • Oct 22, 2004
  • #25
I am kind of in the same boat as you 90. I have a 351w already bored 40 over and fully rebuilt, but I will be faced with using my existing 302 stuff. I just put this combo together a year ago and will be on a serious boder line food stamp budget because of it. I would suggest stroking it. The first time you stomp on it and rip the seat bolts from the floor board or grenade your tranny, it will be well worth it.
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
2,773
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89
Dallas, GA
Oct 22, 2004
#26
  • Oct 22, 2004
  • #26
Leakdown test results:

Did a leakdown test today using a Snap On Leakdown Tester: Results measured in percentage of leakdown.
Rating are:
00-10 - Excellent
11-20 - Good
21-30 - Acceptable
31-40 - Trouble

My engine:

1 - 32%
2 - 36%
3 - 26%
4 - 30%
5 - 42% :damnit:
6 - 50%
7 - 42%
8 - --% not enought time so I didn't get to it.

Just another excuse to tear it down.
 
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