Street 383 recommendations

-
I ran that same basic spec Thumper in my son’s 10-1, 360 in his ‘91 4spd pick up truck. It was good. I liked it. He loved it.
 
I think it's the dead best street grind ever and that Summit cam is basically it. Almost makes me wanna find a 383. LOL
NOTE! I have a complete '64 383 out of a Sport Fury, that is the hp motor for that era. Intake to pan, with oem exh man and like new Hughes am/lifters. S E Tx. $600
 
I ran a 383 with that thumper cam, Performer RPM, and an 850 Holley dp, and it would snap your neck at go and pull like a sob.

It didn't sound any different to me.

I wouldn't be against swapping it out for that Summit cam, but with all the new cam/lifter horror stories out there lately, don't really want to roll the dice and fix something that isn't broke.

Got another 383 that I bought fully rebuilt with a Mopar 'purple' cam.

Is that a specific cam, or are there versions of it?
Can I get away with using the stock stamped rockers?
 
That’s possible. Here’s why….

Probably not likely, but cams can be ground with a smaller or larger base circle than what cam as stock.

Even if it is ground on the proper diameter base circle, the new lifters can have a seat height difference. There was over .100 between my MP solid lifters and the Comp Cams solid lifter. That my dear sir, is gigantic!

This issue with lifters are, where the plunger sits and how far down the pushrod pushes the plunger down. There has to be some travel. This amount differs from lifter to lifter manufacture to manufacture.

The only good thing is if you stick with a MoPar lifter, the seat height (should!) always be the same for whatever style you are working with.

Comp cams has 2 tools which IMO everyone should have and that’s adjustable pushrods for checking length & a 12” dial caliper to measure the pushrod length.

You could just roll the dice and see if the pushrods fit in between the rocker arm and the lifter while it is on the cams base circle.
If the pushrod doesn’t depress the lifter or is just outright obviously short, then ether get the tools or call a buddy over that has them.

I’m sure the pushrods will fit if you use MP lifters. There’s no issue mixing lifter brands and camshafts.
 
You can always use something like the ductile iron rockers 440 Source has. It'll give you a little adjustment.
 
-
Back
Top