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Hey guys my young bloke is into speedway and his class only allows the production carby for that model. My question is what can i do to a varajet carb to get more power. Engine is black 202 with 11.3 comp (all ccd and measured)258 at 50 cam and has a converted to mech sec varajet with standard manifold(which can't be modified).
Carby is allowed to be modified as long as it looks standard visually. On the chassis dyno it makes 141 rwhp on premium fuel(rules) and another car was dynoed earlier with very similar specs and made 153hp. But the owner wont give out any secrets to his carb .
Also the head can't be ported at all from standard and to have stardard size valves and rest is open to mod.So i'm guessing that there must be power to be made out of the carby . Any ideas or no someone with expertise in these carbies. Thanks guys Dave
MONARO!!WHERE!!NICE |
MONARO!!WHERE!!NICE |
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All we done was remove chock butterfly totaly, bored out the venturies and removed the steel inserts in the manifold, cut the center devide , smoothed after filling all holes (egr etc) with liquid steel. Have a couple of carbs handy to get it right and if |
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Rank: Veteran
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Varijet 2 = 398 CFM
Varijet 1 = 375 CFM
that should be worth 5-10 HP.
A1 Bogan. |
Old holdens brought on the spot, quick decision, cash paid. |
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Rank: Member
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Thanks for the response fellas, is a varijet 2 and will try these mods asap . Are the available jets for these or will i have to drill them and what sizes would recomend.
Im not sure if id get away with altering the manifold as the rules states this.
Da |
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Rank: Member
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Thanks for the response fellas, is a varijet 2 and will try these mods asap . Are the available jets for these or will i have to drill them and what sizes would recomend.
I'm not sure if i'd get away with altering the manifold as the rules states this.
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There should be no reason that you couldnt block the egr valve off and remove the butterfly in the exaust as well, the jet sizes I used where the same size as in the quadrajet off a 308. I dont know how hard they scruineer the car where you race (where a |
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our class is QSCA street sedans and ive done the erg valves and butterfly which is allowed and will check on the steel insert as no one up here has mentioned that. I removed the choke flaps and seem to respond quicker . How much did you take from the vent |
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Rank: Member
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our class is QSCA street sedans and i've done the erg valves and butterfly which is allowed and will check on the steel insert as no one up here has mentioned that. I removed the choke flaps and seem to respond quicker . How much did you take from the ven |
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Cool, Queensland Saloon Car Association, they also run with ASCF. Maryborough has picked up alot since Bundy shut down (shame I liked the Bundy track) Whats your home track?
Any way getting back to the car its a patiance job and fiddly you need to take |
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Maryborough is our home track and its a big shame about Bundy track .I have access to a flow bench so i might flow them as well .Street sedans is the way to go if you move to south east QLD they race at Maryborough, Gympie,gladstone,Rocky, Kingaroy, and |
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A flow bench is perfect! Thanks for the heads up on the street sedans, I will look into them when we move and with a bit of luck we have an inspection tomorrow and I may be up there for christmas! Hope you find those few extra HP and good luck for the res |
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