M1 intake

[bemiller]

I recently replaced my Torker intake with a M1 single plane. The car slowed down at least .15. Before M1 ran 11.73 on hot days. After M1 ran 11.83 on cool days. I ran about 4 races with the M1 changing jets and such with 11.83 being best time. Seems like a waste of money. The car is a 69' Dart with a 383. Running .557 cam, 12.5 pistons, 3800 stall converter, 4.56 gear. The heads are faily stock (unported). Could this be problem. Any suggestions appreciated.

[Christopher]

I would call Mopar on this.I belive the M-1 on a 383 works best if there are some fuel distribution dams epoxied to the floor.I can't remember for sure ,so I'd call them.

[340king]

Did you port match the new intake to the heads and was the old intake port matched? Usually Edelbrock is very small on the as-cast port size. If the M-1 was not checked for proper port alignment and size, a slight drop off in perfromance can be expected. It is very easy to check port alignment on the RB-B M-1's as you can just remove the carb and look down the ports.
If the intake port on the head is smaller than the intake itself, then you could expect a reversionary reaction in the intake and would lose HP. Single pattern cams are more susceptible to intake reversion. Also, some of the early production smallblock M-1's had some core shift problems. You may want to check that.

[bemiller]

Thanks for tip, actually I never checked, so it's probably not matched, I did clean the casting flash out of intake though but the heads haven't met the die grinder yet.