No, the old 4 bbl is also made from GM TBIs. We think it was just too much injector for fuel system layout that was used.
No, the old 4 bbl is also made from GM TBIs. We think it was just too much injector for fuel system layout that was used.
The man who says something is impossible, is usually interrupted by the man doing it.
Cool throttle body!
Glad to see someone else's work bench looks as bad as mine.
Interesting.
For years I've wanted to build a two or three TB intake using the smaller 2bbl units found on 2.8 truck engines but I never thought about a dual bore unit like that. The smaller bore should be better for response and would be less likely to allow fuel to drop out of suspension provided you can tailor the AE curves correctly. I wonder if there's any advantage to swapping to late / big block injector pods and using pfi injectors with fuel pressure as high as possible to keep droplet size small?
Very interesting indeed. I'm intrested in how you connected the throttle linkage. Do you have it set up to where both shafts open at the same rate, or do you have it rigged up like a old 4v carb with mechanical seconairys.
79 Jeep Cherokee, AMC 401, T-18 manual trans, hydroboost, 16197427 MPFI system---the toy
93 Jeep YJ Wrangler, 4.0L, 5 speed, 8.8 rear, homebrew hub conversion and big brakes, hydroboost, 2.5in OME lift, 31x10.50's---the daily driver
99 Jeep WJ Grand Cherokee limited, 4.0L, auto, 2wd, leather and power everything, 99% stock---the long distance highway ride.
Right now the throttle linkage just opens both throttle shafts together. Eventually, we might set it up to be progressive, but I will have to build a progressive injector controller to do that, to reduce possible flooding of the later opening throttle plates.
We plan to run it about 20 PSIG or so, at WOT, and use the vac ref FPR to bring fuel pressure down for idle. With the current TB, we could get it to either run like a scalded cat with high fuel pressure, or idle along, and have good manners at part throttle with lower pressure, but couldn't seem to get both.
BTW, it flows over 1100 CFM, dry flow flow.
The man who says something is impossible, is usually interrupted by the man doing it.
That's similar to what I had originally planned for my Camaro, but I decided to keep the linkage simple, and mounted them the same direction and real close.
1978 Camaro Type LT, 383, Dual TBI, '7427, 4L80E
1981 Camaro Z-28 Clone, T-Tops, 350/TH350
1981 Camaro Berlinetta, V-6, 3spd
1974 Chevy/GMC Truck, '90 TBI 350, '7427, TH350, NP203, 6" lift, 35s
Conjoined twins!
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
Bookmarks