I'd like to make contact with a fuel economy guru/ rocket scientist to discuss some of the finer points of optimizing my fuel/ spark curve in the 1- 2,000 rpm range.
Recently I swapped my TBI for a carb as a temporary fix on a malfunctioning, tired, O2 sensor fouling, high mileage engine while I'm finishing a rebuild.
Along with that came a set of recond. ported 041 heads (65cc 1.94/1.50 '70 pass car) This raised the CR a bit, and improved the flow. I wasn't sure how this would go cause the added comp could cause the rings to let go, but so far so good.
The swap also allowed me a opportunity to experiment with the fuel/ spark curve unrestrained by the limitations of the factory settings which I don't yet posess the technology to deal with.
I expected good things and I found out that in addition to more power, there was an improvement in fuel economy. Highway seems about the same but in town it's noticeably better. I haven't done any measured tests but I can honestly say that I'm spending less on gas than I was before the mods, and that was when gas was .15/gal cheaper.
The thing is, outside of the bare basics, I don't really know what I'm doing. I'm just using the hotrod basics along with a small cam, and SOTP tuning. I realize there's a lot of fine tuning that could be done and there would be even more improvement.
I'm not gonna make any mileage claims yet cause I haven't measured it but it's better than it was before and I was getting about 17 hwy, 11 in town then. I'd be really excited if I could get 20 hwy.

Any Help? Thanks in advance

 

17 and 11 WTF? that sucks soooooooo bad....damn, man even my leaky injectors on my tpi don't stop my car from getting 26mpg on the highway....(trip to NC, my odometer is bustedm but My 01 S10 Crew Cab was following so.... i used that one and i used less gas then that thing with its new 4.3 V6, it was gettn like 24.

 

Hot rodding cars is about increasing effecency of the engine. Therefore as long as you don't change your driving habits the more efficent engine will get better mileage.

 

I should have mentioned, It's a 1/2 ton 4x4.
So where's my rocket scientist???

 

Uhh, I think I got lost. Didn't I log into a 3rd gen f-body site? Invoke a highway lean cruise mode and tune the EGR up nice, you should see an improvment. I would imagine the weight and lack of aerodynamics would be the next area to work on.

RBob.

 

Thanks,
I'm not really complaining, my MPG numbers are pretty good for a full size 4x4 IMO, especially for a backyard guy like me. What I'm looking for is to fine tune the spark curve, the carb stuff, I've pretty much got dialed.
Yeh, I know this is a car site, I'm walkin' on eggshells aren't I