return line on mikuni...
#1
return line on mikuni...
wel guys i just finished tinkering around with thw widebody today and just wanted to share with you what i did....but firswt some history...
i've been running a mikuni phh 44 with holley red, and holley fpr on my 1/2 street port 12a for the last few months.... and up unitl today i could NEVER get it to run as well as it did with the ol' nikki... i suffered from HORRIBLE mileage (read: 150 miles a tank) and poor all around drivability..i.e. surging, bucking, stumbling..poor idle. Well i'm happy to say that al of that is gone!!
and here's what i did... i'm still using the same holley red pump..but i upgraded to the holley 4.5-9 psi reg. Now for those of you that own a mikuni you know that most of them did come with a t-fitting for the fuel inlet (normally used to feed next carb in series when running doubles/triples.) what i did was hook this up to the stock return line on my 81.. now before everyone freaks out about working the pump too hard or losing pressure let me tell you the next step... i also hooked up a Mr. Gasket style in-line regulator post carb and before the return hard line... now what this does is efectively slow down return flow to maintain pressure under hard aceleration..
after a little tunning she seems to be running best with the fp gauge that's mounted on the holley fpr reading about 5.5 psi..and the in-line return regulator dialed to about 1 psi...this efectively keeps the pressure around the recomended 4-4.5 psi when underload.. and i'm happy to say that my car has never run better/smoother/ or stronger...and i just filled up so i'll post if there's been any mileage improvement..
just wanted to share with everyone...hpe that it helps anyone possibly experiencing similar symptoms...also if anyone can think of any negative sides to this mod by all means please share..also i'll try to post pics in a couple days...
i've been running a mikuni phh 44 with holley red, and holley fpr on my 1/2 street port 12a for the last few months.... and up unitl today i could NEVER get it to run as well as it did with the ol' nikki... i suffered from HORRIBLE mileage (read: 150 miles a tank) and poor all around drivability..i.e. surging, bucking, stumbling..poor idle. Well i'm happy to say that al of that is gone!!
and here's what i did... i'm still using the same holley red pump..but i upgraded to the holley 4.5-9 psi reg. Now for those of you that own a mikuni you know that most of them did come with a t-fitting for the fuel inlet (normally used to feed next carb in series when running doubles/triples.) what i did was hook this up to the stock return line on my 81.. now before everyone freaks out about working the pump too hard or losing pressure let me tell you the next step... i also hooked up a Mr. Gasket style in-line regulator post carb and before the return hard line... now what this does is efectively slow down return flow to maintain pressure under hard aceleration..
after a little tunning she seems to be running best with the fp gauge that's mounted on the holley fpr reading about 5.5 psi..and the in-line return regulator dialed to about 1 psi...this efectively keeps the pressure around the recomended 4-4.5 psi when underload.. and i'm happy to say that my car has never run better/smoother/ or stronger...and i just filled up so i'll post if there's been any mileage improvement..
just wanted to share with everyone...hpe that it helps anyone possibly experiencing similar symptoms...also if anyone can think of any negative sides to this mod by all means please share..also i'll try to post pics in a couple days...
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