Dynamometer Results & Comparisons - 383 466hp/470ft lb

Just had the 383 dynoed yesterday. It put down 466hp and 470ft lb. Thats with the room the car was dynoed in being a 104 degrees and on a set of drag radials with only 16psi in them. I'm pretty happy.

whats your setup?

Nice tq

Details on setup?

MS4 cam with 1.8 ratio rockers, hand ported 241 heads, 12.25:1, ported FAST 102, 1 7/8 headers, true dual 3", 93 octane, 6spd, dana s60.

The tq was awesome. I'm gonna switch to solid roller this winter and try to pick up a little more.

I would just go with a bigger head/cam. All your supporting mods are there, big intake, big headers, now give it the heads/cam to match those bigger cubes and youll see 500+ no doubt.

I just need solid roller lifters and more duration. The MS4 with 1.8 rockers is .690in .645 ex with a little over 240 duration on both sides and a 111.5 lobe sep. I'm thinking of going with something like .720in .690ex and mid 250's duration on a 111 lobe sep. I don't think my heads are holding me back. They flow about 330cfm at .700. I know my lifters are holding me back. My spring pressure is 161lbs on the seat and 500lbs at .700 and over 550 at .750. I have comp 850 lifters now and know they can't take the spring pressure. My peak hp is only at 5800rpm and it falls quick after that. By 6500rpm its completely done. I can tell by looking at the graph that it starts to loose valve control after about 5200rpm.

Yeah Your having big time valve control issues for sure, you should be peaking at or around 65-6600 rpm, the MS4 with 1.8's will be seriously hard on valvetrain parts!
for a solid roller i'd go 250i-256e .660 lift 113lsa cam, much bigger than this and your just going to be a race only deal and with 1.8 rockers you'd be around .674i .672e net lift = after lash, and btw that extra .030 of lift isn't gaining more than 1-2 engine hp but it will kill springs a lot faster, run 200lbs seat pressure minimum and 550 open, set the springs so that at max lift your .050 away from coil bind
My best advice though is to use TD shaft Rockers!
PS who got 330cfm from your 241's? has that been verified?

Yeah, I know it's real hard on my lifters and springs. This car is just a Saturday night special anyways. I've had the car almost a year and a half and only put 5000mi on it. Most of that was in the first 6 months till the newness wore off. The idea of running a .720 lift cam is that flow numbers pretty much peak around .650 lift and don't fall off until past about .750 lift, so if I keep the lift a little on the high side, it will be in peak flow numbers for much longer than if I used a cam around .650 lift. The car made a very noticeable gain in power by switching from 1.7 to 1.8 rockers. And yes the flow is verified. They are one off heads done by a guy in his garage. He really knows what he is doing. It shows by my dyno numbers. 466 by 5800rpm on a 383 is really good. I can see in the graph it starts having valve control issues around 5200rpm too.

Anybody want to buy my cam, rockers, lifters, and a set of pushrods?