|Username||Post: Need 383 Input For Build|
02-04-20 06:57 AM - Post#2785848
Building a 383 for street use and have a couple questions. I’m striving for about 10:1 compression so it can be safely driven on 91 pump gas. I planned to get one of the Eagle or Scat balanced rotating assembly stroker kits from Summit. Does anyone have any experience with these?
Secondly, with trying to get to my compression...according to Eagle's website, if I run 64cc heads, I’d have to get their +12cc pistons (9.67:1) or if I run 70cc heads I can get their more flat top pistons at +5cc (9.85:1). My question is, would you have a preference in combination? I feel like the 64cc heads may be more universal to have down the road in case you ever wanted to put them on a standard 350?
I’m open to any assembled aluminum head in the ~$1k price range. Currently considering the Brodix IK 200’s
"19th Year" Silver Supporting Member
02-04-20 08:49 AM - Post#2785855
Your static compression ratio is not as important as your dynamic compression ratio, and that will depend a number of factors. Read the post about dynamic compression ratio. Most people will recommend flat top pistons over dished pistons as flame travel is more efficient. Your cam, compression ratio, rod length, and combustion chamber must all work together to give you the best possible combination to fulfill your goals.
SCAT and Eagle are both good sources. According to builders, SCAT has fewer quality control issues.
02-14-20 01:28 PM - Post#2786506
I did a lot of research for my street 383 build and I am very pleased with the results.
My compression ratio is about 9.7 with a .040 quench. I used Promaxx Maxx 64cc heads which look very much like (almost identical too) Brodix. Everything about these heads were spot on out of the box, EXCEPT they didn't put thread sealant on the screw in studs going into the water jacket, so that would be something to check. These heads were just under $1000 when I bought them a few years ago.
In case anyone is wondering ... I was a little concerned about buying these heads, but there is a guy on youtube who did a multi-video review of these heads and after watching his videos I was more than willing to try them and I am happy I did.
My rotating assembly is SCAT and I used -12cc pistons. I used a short duration camshaft 211/219 @.050 with about .515 lift and couldn't be happier.
If you have any questions about anything just ask.
Super Senior Member
02-14-20 03:59 PM - Post#2786521
I couldn't be happier with the 383 I built for my Express van.
6" rods and forged flat tops with 2 deep valve reliefs. +6cc.
It is 11:1 compression with 0.040" quench.
Assault Racing castings ported by Lloyd Elliot that ended up around 215cc.
Lunati Bootlegger 232/244 @ 0.050 roller on a 108 LSA and 104 ICL.
Rhoads V-Max lifters that knock 20° iff the duration at lower engine speeds.
Mercruiser dual plane MPI intake with a 1,200 cfm 4bbl throttle body.
4" air intake with a 100mm MAF sensor.
Doug Thorley Tri-Ys into the stock dual 3" exhaust tubing.
Dual 3" in/Single 4" out muffler.
Pulls strong with a 2,800 stalled 4L85E and 5.13 rear gear.