CLASS RACER FORUM - Christmas continues for MOPAR rsacers

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Re: Christmas continues for MOPAR rsacers

Quote:

Originally Posted by Sam Capizzi Jr (Post 364836)

The 318 2bbl motor has two major issues... Intake/carburetor and Valve clearance. Right now I'm using a 240 duration cam at .050 and I have .025 clearance on the intake and .040 on the exhaust. If they would allow a 4 eyebrow 318 replacement piston, the combo would be good at 185 hp and would pull high rpm with more cam... Btw the 69 motor has .031 less clearance.

Well Sam, if you can stand another FWIW(don't ya just hate us keyboard racers?). I don't know how bad your intake is but I do know that some of the early 70s 318s had a single plane intake that doesn't look bad and the carb is bigger than the carb I'm allowed to use on my 307. Have you ever had the heads on a flowbench? What kind of cranking pressure (cylinder pressure) do you have? I'm asking because I think that your cam is a little too big. Shorten up that duration (and tighten lobesep?) and you've got valve clearence. What have you got for header dia? length?

Re: Christmas continues for MOPAR rsacers

Quote:

Originally Posted by Billy Nees (Post 364906)

Lets see...
There are two intakes listed. (3698431 and 3698437) Ill have to try and find the one ending in 7.

Heads. No flow bench

180psi cranking pressure

Headers are 1.50 dia with 3' out. Not sure of length but has 12' collector

Re: Christmas continues for MOPAR rsacers

Quote:

Originally Posted by Sam Capizzi Jr (Post 364919)

Lets see...
There are two intakes listed. (3698431 and 3698437) Ill have to try and find the one ending in 7.

Heads. No flow bench

180psi cranking pressure

Cam is .240/.246 109 advanced 4

Headers are 1.50 dia with 3' out. Not sure of length but has 12' collector

Well FWIW, I'd like to see what the other intake looks like.
180 psi is OK but I'd like to see it around 200.
I'd love to see that things reaction to about a .236/.240 on a 108(or even a 106) and with a lowgear TF it shouldn't need the cam advanced.
1.50 headers are right but I'd like to see it's reaction to a 2.5" collector.

Re: Christmas continues for MOPAR rsacers

Quote:

Originally Posted by Billy Nees (Post 364931)

Very useful information. This is the first cam I've tried but I'm working on second one. The only reason I went with the 109 was to gain some clearance. I had the 2.5 collector on the car and it was a tenth slower then the 3. No low gear in 904. Yet. Next time it's out. Also use 4.56 with 28 tire

Re: Christmas continues for MOPAR rsacers

Sam: You Really need a 275 low gear! They came in some of the
later 70s- 80s cars. When I put a spare trans in my 340 low comp.
stocker it went from 1.45 60s to 1.58 and would not fall out of a tree!
The difference should be pretty dramatic on your Duster.
I used to get them from a Transmission parts core shop in Vegas .

Bob Mazzolini Racing used to sell them by themselves years ago.
If you can not find one..........let me know and I will start looking for one
they are not expensive and probably a lot of Mopar Guys have some
laying around.

The next thing I would try to find is a Aluminum front Drum as they make
a good improvement for the money.

PM me if I can Help!