Part of building these things is tuning and lot's of it. Built from scratch means tweaking this and that to get things optimal. I've had a tip in hesitation since day one, my plugs are burning a little fat, and my radiator recovery system needed some work.
With a MSD Pro Billet distributor you have no vacuum advance. With a large camshaft that means low vacuum at idle. To help with vacuum and signal to the carb you want as much intial timing as possible. The problem is as you increase intial you increase total. Today I pulled my distributor apart to find a 21 degree bushing and the heaviest springs MSD makes. Not optimal by any means. I replaced the bushing with the black 18 degree and used the blue springs. Now advance will come in 500 rpm sooner and I can add 3 degrees initial timing.
My engine was dyno tuned in NC. I am at 2500 ft elevation and in a drier climate. I have used formulas in the past to change jets on my quad. Basically I needed to jet down .002 front and back to 79/87.
I was using a catch can which would probably work for some. With the half height body bushings it does make your engine set higher in relation to the radiator. Basically what would happen is I would top it off and drive it, as the coolant expanded it would go in the catch can . Well after a few drives the coolant would get low enough it would get an air pocket in the intake at the sensor. No problem if I topped it off ever couple times. Now I have a recovery style resorvoir. It will pull the expanded coolant back as it cools like a new car.
So I rejetted and reset the float levels, adjusted the air mixture screws and added a few degrees of initial timing. Car has never run better or smoother. In fact it's helped my vibration at freeway speeds 85-95. The poly engine mounts go in next and that will eliminate almost all of that. Tip in heistation has vastly improved. Probably going to have to send in the metering blocks to get rid of it 100%. For now it's 100% better than before all the tweaking. All and all one of the best days of work yet. Just keeps getting better!
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
Next is the trunk carpet and box for my subwoofer. Then it's plug and play. Should have a really good sound system. Then I am on to finishing the interior. Back seat, rear panels, and AC/Heat. This flywheel deal put me behind.
Linear Mode
