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Punk in Drublic
11-20-2004, 01:55 PM
i got a built 300-I6. its got a lumpy cam .030 over ported and polished head, dual port offy intake, 390cfm holley, with almost stock compression(block has been zero decked) is a stock exaust(2.5inch) with a cherrybomb enough. i was planning on getting a dual setup as i am using the shorty manifolds of an 87 and figure it'd be pretty easy to just throw some pipes on each and send them through eithe glasspacks or maybe flowmasters.

know ive been thinking about going cheap and keeping it like it is, or blowing some mone and getting a custom header made.

i am plannig on going nuts on the motor in a few years (.060 over, stroker(clofford once made a kit and i will find one) high compression, turbo etc. etc.)

should i just wait till then.

Tom or anyone else in the biz what kinda pries would i be talking for a header (PM me)





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u2slow
11-20-2004, 05:39 PM
I think a single 2.5" is plenty.

I had a 2.25" single on a 250 Chevy straight six, and it was okay - but I thought more had to be better. ;)

Then I went to dual 2.25" and headers ... Boy did it suck [xx(]

My conclusion was the six makes its torque down low, and the big exhaust just kills it. Also, the six can't rev up high enough to realize the extra flow potential.

Lordco performance can order this stuff:
http://www.cliffordperformance.com/Site04/ford_240_300.htm

STranger
11-21-2004, 05:35 AM
like he said^^

i dont need people to get me,i just need people to get out of my way

barracuda
11-21-2004, 06:25 AM
Off of your ford cast iron shorty header based 3 into 1 manifold goes into a 2" tube and then both 2 inch runners tie into a 3 inch tube and after that it reduces down to a 2" tube. Go back to where it is still a 3 inch pipe and put in a 3 inch exhaust .
Now before people start talking about back pressure it is Velocity and frequency occilation and flow which are important (actually it is the relationship of these three ).
The two inch runners will give you the required veocity for your engine combo (3.14 area each) and the 3 inch actually flows better that two 2" tubes .
(7.068 vs 6.28 area and the three inch has less parasitic drag on the walls of the tube 9.42 for the 3" and 12.56 for the 2" (2"x2)of surface area to create parisitic drag)

Your biggest problem right now is that you are running a low flow cat and only a single 2 inch pipe . if you run a single 3" you will get alot more flow . and at a later date if you desire a header it will work well with that also . I think that once you open up the exhaust you will notice a big difference .

PS what do you call a lumpy cam??? Mine is 208 at 050 and i would not call that lumpy . what cam do you have(brand specs model number etc) and dont just say RV cam because it is a term that is so ambiguous that it is of little use .


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Punk in Drublic
11-21-2004, 09:39 AM
it is a comp cam, i think this is it:

Camshaft Specification Table
Part Number 66-248-4
Engine 1965-1996 Ford
240ci-300ci
10.00 Deck,
6cyl.
Grind Number F60 268H-10
Description

--------------------------------------------------------------------------------

Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.456 0.456
Duration At 0.006 Tappet Lift 268 268

--------------------------------------------------------------------------------

Valve Timing At 0.006
Open Close
Intake 28 60
Exhaust 68 20

--------------------------------------------------------------------------------

These Specs Are For The Cam Installed At 106 Intake CL
Intake Exhaust
Duration At 0.05 218 218
Lobe Lift 0.2853 0.2853
Lobe Separation 110

--------------------------------------------------------------------------------

Recommended Valve Springs 6903



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barracuda
11-21-2004, 03:40 PM
I wouldnt say you are over cammed . that cam should work well with your set up as long as your compression is sufficient and you open up your exhaust. the factory ford comes out of the cat at 2" diameter which is to small even for the stock engine.

"A level" mobile welder
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Punk in Drublic
11-21-2004, 07:15 PM
cool, so i'll just go three inch from the collector back. u say the collector before the cat is 3"? i think three inch with a flowmaster 4 series would be nuckin futs on a six. think that setup would work well with my cam/carb

Necrophilia: roll over and crack open a cold one