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CarburetorsCarb discussion and questions. Upgrading your Third Gen's carburetor, swapping TBI to carburetor, or TPI to carburetor? Need LG4 or H.O. info? Post it here.
87 iroc going carb cannot resolve efi issue.So have all required parts except fuel bypass .Can some one recommend a good quality afpr for my project as it I'm using the stock pump but need to dumb down the fuel pressure.
What is wrong with the EFI? Going to carb is a massive downgrade probably better to fix the origonal system
My last venture was to put a new regulator in and gas spilled out imy exhaust. I took reg out and it was torn.wtf.A brand new part defective pissed me off.So that made.up my mind.
Last edited by Chaddyboy; Sep 14, 2023 at 11:56 AM.
I did the exact same thing. Changed from TPI to Carb on a ZZ502 base. I also went with the MSD Billet distributor so I could change the advance curve and all in timing. If you have WBO2 in one or both sides, it will help you with the carb set up. I initially used the Holley 870 as it was the OEM on the Deluxe zz502. I dropped back a bit with an AED 810 cfp. I have had to drop primary jets and the AFR a bit to get the mixture to lean out some.
The regulator you need is the Aeromotive 13220. A two stage regulator where the first stage dropped from 50 or so down to 18 psi. The first stage is bypass. The second stage drops from 18 to 6 or 7.
For the record, I am glad I made the change. I spent a long time with Tunerpro and never got it where I felt that I didn't need to carry around my laptop.
I did the exact same thing. Changed from TPI to Carb on a ZZ502 base. I also went with the MSD Billet distributor so I could change the advance curve and all in timing. If you have WBO2 in one or both sides, it will help you with the carb set up. I initially used the Holley 870 as it was the OEM on the Deluxe zz502. I dropped back a bit with an AED 810 cfp. I have had to drop primary jets and the AFR a bit to get the mixture to lean out some.
The regulator you need is the Aeromotive 13220. A two stage regulator where the first stage dropped from 50 or so down to 18 psi. The first stage is bypass. The second stage drops from 18 to 6 or 7.
For the record, I am glad I made the change. I spent a long time with Tunerpro and never got it where I felt that I didn't need to carry around my laptop.
Don
Williamsburg, VA
Yes that regulator you mentioned isn't cheap.However I chose the holley regulator mention by the other member .I'm running a eldebrock carb 650 cfm should be fine.
I initially went with a Holley Regulator but it did not bring the FP down to 7 psi. I have the Walbro 255 LPH pump in the tank (for the BBC) and maybe the volume was too much. I have spent so much money on this car, a few more hardly counts.
Thats a beautiful machine.I still have to figure out my throttle body cable connection as mine was originally a multiport.Ps I bought a 340lph fuel pump and it destroyed my regulator diagram split open not good.
What transmission are you running. If 700r, you will need the right adapter for the holley and the lock up stuff.
That BBC TPI set up is waiting for a new home. Oval port.
Don
yep it's the 700r tranny .Im running a eldebrock carb.Im told i will loose my lock up if i dont set it up or loose a few mpg.However this is just a weekend driver
There is a sticky at the top of this forum about lockup. I installed the Ron Francis lock up. It is based solely on MPH. Has a speed sensor that you connect to the transmission. It requires you to run a brake interrupt line from your brake lights. I also put in a relay that would not allow the TCC to lock unless I was in 4th gear. The 4th gear switch out of the trans goes to ground when in 4th. I put an idiot light to know when I was shifting to 4th. I also put a separate idiot light for lock up. Finally, I put in a vacuum switch that would unlock the trans if i was above the speed but hit the gas (dropped vaccuum) for passing, etc.
