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Old 12-28-2008, 06:55 PM   #1
10.5
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Default Is this a decent cam?

A friend of mine has an engine that is set up to be a "nitrous" engine. The cam in it is absolutely huge. Do you think it's too big?

.816/.803
274/294 @ .050
116 LS installed @ 113

Valve events: OPEN--int 24*BTDC, exh 86* BBDC, CLOSE--int 70*ABDC, exh 28*ATDC

Engine is a 440" windsor, 4.070 x 4.23
~13.4:1 compression ratio (1.3cc dome)
Victor Jr's (flow 324 on intake)
Super Victor

Motor only has ~155 lbs cranking compression...is this normal and due to the cam size?


Thanks!
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Old 12-29-2008, 10:43 PM   #2
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I think its too much camshaft. Do those heads actually flow at .800 lift?
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Old 12-29-2008, 10:58 PM   #3
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Quote:
Originally Posted by 10.5 View Post
A friend of mine has an engine that is set up to be a "nitrous" engine. The cam in it is absolutely huge. Do you think it's too big?

.816/.803
274/294 @ .050
116 LS installed @ 113

Valve events: OPEN--int 24*BTDC, exh 86* BBDC, CLOSE--int 70*ABDC, exh 28*ATDC

Engine is a 440" windsor, 4.070 x 4.23
~13.4:1 compression ratio (1.3cc dome)
Victor Jr's (flow 324 on intake)
Super Victor

Motor only has ~155 lbs cranking compression...is this normal and due to the cam size?


Thanks!
Not really. how heavy is the car? and how hard are you going to spray it?
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Old 12-29-2008, 11:04 PM   #4
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looks like it might be in the ball park. Depending on the headers that LSA may need to be tightened up but you might wanna chase the ICL around before trying that if the car is unresponsive to tunning changes.
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Old 12-29-2008, 11:25 PM   #5
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Car weighs 2950lbs w/ driver

Here is the flow sheet: (intake only) All at 27.95 depression

.300--186.1
.350--211.5
.400--236.1
.450--262.8
.500--284.3
.550--299.1
.600--315.6
.650--324.8
.700--324.8
.750--320.1
.800--321.2
.850--325.5
.900--324.3
.950--326.2


Planning to spray somewhere in the range of 34N/30F or 36N/30F on an Edelbrock fogger w/ E-2's.

Headers are only 1 3/4 to 3" collectors--3" exhaust to the axle.

It just seems that this cam bleeds so much cylinder pressure, but I'm just curious with the amount that will be sprayed, will it be fine? How much more (if any) power could be picked up with a smaller cam?

Thanks for the input!!!
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Old 12-29-2008, 11:44 PM   #6
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Cranking compression is not terriably useful for figuring out what cylinder pressures will be in the intended operating range.

Run it and see what happens. IMHO the headers are to small so that wide LSA will help you. If you are after more cranking compression though advance the camshaft if you have sufficient Piston to Vlave clearance.

Quote:
Originally Posted by 10.5 View Post
Car weighs 2950lbs w/ driver

Here is the flow sheet: (intake only) All at 27.95 depression

.300--186.1
.350--211.5
.400--236.1
.450--262.8
.500--284.3
.550--299.1
.600--315.6
.650--324.8
.700--324.8
.750--320.1
.800--321.2
.850--325.5
.900--324.3
.950--326.2


Planning to spray somewhere in the range of 34N/30F or 36N/30F on an Edelbrock fogger w/ E-2's.

Headers are only 1 3/4 to 3" collectors--3" exhaust to the axle.

It just seems that this cam bleeds so much cylinder pressure, but I'm just curious with the amount that will be sprayed, will it be fine? How much more (if any) power could be picked up with a smaller cam?

Thanks for the input!!!
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Old 01-01-2009, 02:55 PM   #7
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top post is right.
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Old 01-01-2009, 04:11 PM   #8
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heads and headers to small for cid and camshaft, it will work but can be alot better.
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Old 01-02-2009, 09:28 AM   #9
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Quote:
Originally Posted by team hyperactive ez555 View Post
heads and headers to small for cid and camshaft, it will work but can be alot better.
That's exactly what I thought...kinda stuck with those heads though. That being said, would this set of heads/headers make the best power with a smaller cam, or will this cam do fine. It's one thing to be down by 10-20 hp with this cam...but I'd hate to know that the motor is down by 50+ hp over a better cam.

What is the total amount of spray that this combo could handle with this cam, assuming the tune-up is perfect?

Thanks for all input!
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Old 01-08-2009, 05:34 PM   #10
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Headers are only 1 3/4 to 3" collectors--3" exhaust to the axle.

How did you put SBC headers on a BB?
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Old 01-11-2009, 06:43 PM   #11
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Quote:
Originally Posted by BTL FED View Post
Headers are only 1 3/4 to 3" collectors--3" exhaust to the axle.

How did you put SBC headers on a BB?
Those headers are small for sbc.
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