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i have just dropped a 253 into my hq prem and was looking for tune up settings for the points and timing. also it has a 4 barrel carb but dosnt seem to open the 4 barrels up. it seems like it may have a mild cam and has extracters but i know nothing else about the motor. any help will be greatly appreciated thankyou
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If it is a vacuum secondary carb (which it sounds like) then only two barrels will open at rest. The other two will only open when there is enough load / acceleration to activate the mechanism that opens the second pair of throats.
A good starting poi |
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If the carby is a quadrajet the secondaries will only open when the choke is of.
Warren
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thanks jabba. that should help a lot. just one more silly question, ive never had an 8 before and dont know where the idle screw is. there is two srews in the bottom left and right hand side of the carb and are these what im looking for?
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depends on carb. If it is a holley, go to their website and track down the model you have, and download a setup guide. They are reasonably straightforward.
The throttle linkage / cable will attach to a lever on the side of the carb. The idle screw w |
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The tuning settings are OK as above, and the big secs usually wont open until u get a LOAD up.
The idle screws are those 2 fiddly hard to get to screws in front of the carby.
Next problem is that the internal MAIN jets and MAIN (skinny) rods will be
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trubluhg is right most quadajet carbs must be jetted down to get it to run right( not overfuel) if you know the correct specs for the cam thats in it you can ring the supplier of the cam or even a carbbie place and have a chat with then and they should be
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1) I have a fj 1200cc yamaha I would like to put bigger jets inthe carbbies i'm pretty the one's in there are standad , what are the best and prise in live in queensland ../2) matty here now i have a gpz 600r 1985 model and i have drilled the fuel jets
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Rank: Guest
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1) I have a fj 1200cc yamaha I would like to put bigger jets inthe carbbies im pretty the ones in there are standad , what are the best and prise in live in queensland ../2) matty here now i have a gpz 600r 1985 model and i have drilled the fuel jets ou
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Find out what sort of manifold vacuum you have. 13" of HG is good, higher is better, 5s in bad. The Quad needs good vacuum to ensure that the needles are correctly seated. Dont assume got checkt it.
Also you will NOT see 4 barrels open at IDLE, or stat
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Find out what sort of manifold vacuum you have. 13" of HG is good, higher is better, 5's in bad. The Quad needs good vacuum to ensure that the needles are correctly seated. Dont assume got checkt it.
Also you will NOT see 4 barrels open at IDLE, or sta
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