Hello i have a 1980 Bridgeport rx7 i just got it and I'm having some issues with backfiring on it when i push my gas petal more than halfway down it will backfire. Also, when i am in higher gears it struggles to climb rpms without backfiring too. im running 6psi of fuel pressure i have a electric pump and a regulator. my carburetor is a Holley 650 double pumper the primary jets are 65's and the secondary are 70's i also have a full street exhaust system. im assuming i either need to get a smaller carburetor or change the jets. does anyone have suggestions or solutions to help with the backfiring? also sorry if I'm missing simple knowledge, I'm new to cars in general and especially new to rotaries.

 

welcome to the board.

does the backfiring happen under load or while you're trying to cruise with it?

have you checked the timing? i think you might want to start there.

what are you using to monitor mixtures?

what regulator are you using? have you tried running higher pressure?

 

so, the backfiring only happens when I'm gunning it. so, if I dump the gas to try to climb rpms quicky it's a constant backfire spam. I am able to bring my rpms up higher if I feather the gas very slowly. I'm using a Holley regulator, and I have not tried to run a higher pressure. I also don't have a gauge to monitor mixtures. is there one that works best with my car or one you suggest by chance? also I will check the timing and see what that shows. thank you for your help.

 

well, go ahead and check the timing. no harm in doing that, but my brother's car (an '83 with a street ported 13B and Holley) used to do a similar thing, and it ended up needing more fuel. what pump are you running?

 

the fuel pump im running is a delphil technologies electric fuel pump.

 

do you have the output specs on it - particularly the volume? what i can say is if that pump is some sort of stock replacement, then you probably don't have enough pump for your Holley setup.

 

i think you might be right with the fuel pump not delivering enough I've looked up the part number and it says my pump isn't even meant for gas it says it's made for diesel (thanks previous owner lol). I'm going to have to change it to my Holley one.

 

yeah, we switched to a Holley Red (at least, i think it was Red) on my brother's car and all fuel issues disappeared. we tuned it to the best of our combined abilities and the car ran pretty strong and reliable.