What would be great, but probably never going to happen, is if someone came out with an EFI intake for BBC's like FAST's for LS's. Interchangeable intake runners and plenums.

https://youtu.be/3Q1uLxKAum8 https://www.youtube.com/watch?v=3Q1uLxKAum8&feature=youtu.be

cool video,,fast should make a variable length runner,,like what mazda did,,best of all worlds.

On motorcycles we lost power going to EFI until a second injector was added upstream higher in the air boot effectively giving it the best of both worlds. I wonder if it's worth the trouble to try on a bbc to have the TB actually lick in some fuel on top of the MPI set up?

Isn't the injector setup they used, sort of similar to how Smitty's are setup?

Could be , but his runners are more at an angle vs the injectors. Smitty would have to take a closer look.

Here is a better pic of the Pontiac....runners aren't angled much, so the way the injectors are, they spray pretty much right at the floor, Here is a better pic from that article

If they had bsfcs in .30 to .35 range data was pretty much useless and i wouldnt trust it at all.

[QUOTE=SB;4541011]Could be , but his runners are more at an angle vs the injectors. Smitty would have to take a closer look.
We never tried a carb when i built my mefi controlled pontiac and we only had tailpipe o2 sensors when we dynoed it BUT did have egts and they were 100 degrees apart. Motor made 580 ish, car runs 11.20s at 120 at 3950 plus driver w 3.42 gear. When i freshen it i will be trying a carb on dyno as a comparison!!

This would have to be the worst intake design in world as far as injector placement to give up almost 60ftlbs tq at 4400 besides every where else, injrctors are aimed exactly like the 454r victor we tested. Im going to verify base timing then crank up timing in the timing tables and see what happens, i also ran the lash today and made sure i wasnt losing a wheel or something, lash was pretty good. Might also build a adjustable throttle stop, we'll get to bottom of this one!

You arent taking intake manifold air temperature readings are you smitty ? I noticed on non intercooled roots setup, with carbs, man, the intake air temp drops when the throttles are opened. At cruise speed in the boat, even at 0 boost, the temps are hotter than they are at wot and 8lbs of boost. Id imagine the fuel has to have a decent cooling effect on the air charge.

I guess if you saw say a 20 plus degree increase in intake air temperature, along with the decrease in power, it would kinda make sense. But if the temps were nearly identical, then id think something else was going on . It really be interesting to see how a carb would stack up against port efi when its mid august and the ambient is 90+ degrees.

At 4400rpm, where shes down 60ft lbs, what was the carb setup timing at 4400, vs the efi setup?

33 was most i ran w efi vs 38 w carb, tq seemed to pick up when took timing down to 30 or so when looking at just the tq peak, had alot going on though fri when i was doing it and just had time today to go back and look hard at overal tq, down everywhere besides peak , my actual business is busy right now too so i only have a few hrs a night to dyno or work on setting up the new data aquisition Once the new stuff is installed and working i will be able to plot pulls on the screen w color overlays and see immediately how numbers compare vs flipping back and forth on the antique computer using dos commands , making hand notes of rpms , tq, afrs then flipping back to different pull and doing same thing. So plan is at moment first cool air, dry air day where we have those 2%correction factors going to pull with timing cranked to fawk and see if tq numbers come up. Then not doing any more dynoing till all data aquisition is installed and working as it wil make this more accurate and 10x faster. Ive had a few people ask me whats wrong when im not posting any updates, keep in mind I work 40hours a week on 3rd shift at my night job and 40 to 60 hours in my shop but 45 of those 60 hrs are building transmissuons, machining snowmobile clutches, doing performance tuning and parts upgrades/installations on street cars,race cars, mud boggers, diesel trucks etc. Luckily I do have one full time employee that gets alot done too so if i really burn candle i can put about 15 hours a week towards dynoing my own stuff/installing the data stuff etc. I also have a couple boats coming soon to install blowers on and tune the efi on, customers outdrives to build and on top of that once data stuff on dyno is faster and reliable i have 3 or 4 people wanting to dyno there stuff so in middle of all this i may be tearing my motor off to do paying work!