Ray, what kind of RPM's are you turning at 55 and 65 with your current setup? Is the 413 mostly stock, or do you have a cam, headers, ??? What kind of mileage do you get with your rig?
2700 @ 55
3200 @ 65
BTW the truck versions had a governor set at 3,400 RPM redline!
All stock except HEI and hot/cold air cleaner snorkel
~9-10MPG
working on the code for a RaspberryPi dash computer with fuel meter (I added O2, vacuum, drive shaft, spark and crank sensors)
What kind of MPG improvement did you see as a result of the HEI and cold air induction? Did you do those before or after the switch to radial tires?
Will the raspberry thing be a data logger, or allow control over engine management? One more question- how in the heck are you getting those MPG's using a holley?
Not sure of any MPG improvement, but I have a local hill climb test I do that went from 41s to 39s from a standing start.
Pi has a 7" touch screen just to log / display data ( I normally write a lot of code) and maybe control an air bleed (IAC) that I got for mountain driving. I go up to 9,000' in the Sierras.
The 390CFM 4150 is all the low-rpm motor needs and was built and tuned by Rick Walker Carbs. I think the HEI helped a LOT - certainly runs a lot smoother than the OEM even after it had new bushings and all. I also use Mopar Performance Tune for the timing with a degree tape, and the dizzy was tweaked by The Dyno Shop.
I posted this on Tapatalk years ago:
I just had a 4150C Holley R-6189A gone through, with stagger jetting; no real issues, just confirming it was clean and jets were OEM. These carbs also have the 6.5 power valve and 2 idle screws only on the secondary block.
Holley tech confirmed the set:
L-Pri 59, R-Pri 57
L-Sec 70, R-Sec 72
It is a 413-1 in a Travco RV, and the left barrels see the deeper side of the dual plane intake; I presume that the left jets are larger since that side gets less average vacuum (I get ~16" at idle at 4000').
Once I put the HEI back on I'll be re-checking my O2 sensors' results, and I'm using Champion type 120 plugs at .045
When I was looking at the O2 data before I could see one or 2 were leaner than the others, but because of the cross-over manifold it's hard to tell which.
I also stay 65 or under on the freeway...
