351 W heads & compression?

69Rcode_Mach1

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Apr 20, 2004

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Apr 28, 2004

#1

• Apr 28, 2004

• #1

Hello all mustang lovers out there. I need to know the size of combustion chambers on my heads on my 351 Windsor on my 1969 Mach 1. Its bone stock. I heard that they are 58cc's, but i want to be sure before i go blow money on some pistons. I want to up the compression ratio upto 11.1 what kind of pistons do you guys recommend? I was thinking of JE, but i first need to make sure I have the right size for my combustion chambers.

 

Max Power

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Jul 31, 2003

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St Paul

Apr 28, 2004

#2

• Apr 28, 2004

• #2

Everything I have read says 60cc.

11:1 is a lot of compression for stock heads in todays world.

 

69Rcode_Mach1

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Apr 20, 2004

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May 2, 2004

#3

• May 2, 2004

• #3

really you think so. It is one of the cheap ways for me to get power out of my car since i can do it myself. I was thinking of doing aftermarket heads, but it would be too pricey. Do you know the size of my combustioin chambers.

 

69Rcode_Mach1

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Apr 20, 2004

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May 2, 2004

#4

• May 2, 2004

• #4

o sorry stupid question nevermind ignore the combustion chamber question.

 

Max Power

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St Paul

May 2, 2004

#5

• May 2, 2004

• #5

Hot Rod did a test last year on a 440 Chrysler, and fir every point of compression, they gained about 4% in horsepower. That would be about 25 horse for you.

If you bolt on aluminum heads, 50-75 easy. Plus, you dont have to pull the motor.

 

LMan

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Aug 10, 2002

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May 2, 2004

#6

• May 2, 2004

• #6

C90E and DO0E heads are 64 cc.

11:1 is really pushing it for today's gas, unless you plan to run booster or something similar.

 

Max Power

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Jul 31, 2003

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St Paul

May 3, 2004

#7

• May 3, 2004

• #7

Just remember, flow is more important than compression for this conversation.

And heads are easier to bolt on than pistons. Save your money for heads.

 

Edbert

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Jul 13, 2002

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May 3, 2004

#8

• May 3, 2004

• #8

I kept my comp ratio low on my 351W buildup so pump gas would not become an issue. I am at 9.25:1 and some say I went too low. I'd say 10:1 or so would be the practical limit and followed the thought process of "Max Power" here, it is all about airflow.

 

1320stang

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Nov 13, 1998

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May 3, 2004

#9

• May 3, 2004

• #9

I had '69 351W heads on my race 289 that had 12.7:1 TRW's installed, but that would be with the '65 heads that came on the motor. Best we could figure was that we had lost around a point of compression, somewhere in the neighborhood of 11.7-11.5:1.

I wouldn't go over about 10.5:1 if I were you though, I don't think you'll notice tha half point difference.

 

69Rcode_Mach1

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Apr 20, 2004

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May 3, 2004

#10

• May 3, 2004

• #10

What kind of gas would i have to run. 100 octane?? My goal is to get it up to 400hp at the flywheel. It currently dynoed at 155rwhp which is pitiful, but i am at 5000ft elevation. It runs an edelbrock performer 351 manifold, and a holley 4010 running at 600 cfm. Help me guys!!!(I am new to the performance field.)

 

Edbert

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Jul 13, 2002

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Austin TX

May 4, 2004

#11

• May 4, 2004

• #11

Dump the performer intake, it is an RV intake and only good for a tock cam and saving weight. The Performer RPM is the performance dual plane from them. To get 400fwhp from a 351W is not hard but it is not THAT cheap either. The easiest way I can think of is to buy the entire Perf-RPM kit. Cam, heads, intake and carb. That will put just about any 351W at or near the 400 mark and cost you under $2K (assuming your block and reciprocating assembly is up to the task of course). I almost did just that but I picked a Holley carb and let my shortblock builder change my cam according to their preferences/recommendations. I also overbuilt the bottom end which can take 7500-8000 RPM (but my cam wont ever allow that).

 

69Rcode_Mach1

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Apr 20, 2004

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Salt Lake City, Utah

May 5, 2004

#12

• May 5, 2004

• #12

With the whole piston deal, my friends dad is helping me with that and he built dragsters when he was younger. He said the best way to gain power is up the compression and if you do it yourself it shouldn't be too expensive. I am planning on doing a new exhaust first though since the car is having trouble breathing. I will be keeping all the original parts for down the road when i want to do concours, but until then why not have some fun. Im planning on probably putting on some hooker super comps, X-pipe, and 2.5" exhaust pipes, I just don't know what kind of muffler will get me the most power. Or should i just straight pipe it. I have a ford 9inch diff, and an fmx tranny. Will the fmx hold 400fwhp without problems?? Thanks guys.