whoo knows alot about carbs??

[85/96gt]

hey guys finally put my engine in!!!!
ok wen i bought my car ''85gt'' it had what i beleive is a holly 600 double pumper..( i have a holley book ill look it up and make sure and let you no wen i get time ) anyways impretty sure its a 600dp my engine is as follows
stock bottome end stock gt 40 heads exept beter valve springs e 303 cam performer rpm intake hedman 1 5/8's longtubes carter fuel pump and strait pipes into 2 chambers or race bullets dumped (any imput on what i should go with on mufflers =)? anyways i no that carb is probobly a bit small.. but im on quit the budget adn cant really swing a new carb... will it be fine.. maybe i can rejet it? i was planning on it cause i thougt idd have to .. that and a spring kit.. any idea what size jets to go with? or shoudl i jstu leave it alone and throw it on ? i really dont no what to do any help appriciated much ....

 

[mustangman33]

you should do fine with that 600 double pumper, almost anything higher would be overkill, with anything higher you may be getting too much air and fuel, if thats what came with the engine go ahead and stick with it, or just have it rebuilt.

 

[85/96gt]

ok thanks man ya it did coemw itthe engine '' it was stock then tho '' thats is why i was wondering if it wold be anough for thenew parts...its not stock " but not highly moded by any means.. 280 hp?..but if you say so ill stick it on ..
p.s.. i was goign to get a carb spacer as wel... shoold i get the 4 hole or open spacer?

 

[82boy]

i would have to agree a 600 is right for your combo. i would start out at holley's factory jetting. then go from thier.

on spacers they are a tunning tool. and need to be looked at as such. you may loos power using a carb spacer. its a tool to use. your performer intake is a duel plane intake . if you can try diferent spacers and see what happens. dyno time is expensive but track time is cheap go to a test and tune make a base line then make a pass with one space then another spacer and so on.

 

[battyice]

ok thanks man ya it did coemw itthe engine '' it was stock then tho

Are you sure you don't have the stock carb? 1985 GT's came with a Holley 4bbl stock, although they had vaccum secondaries and plugs over the idle mixture adjustment screws.

I'm not trying to insult your intelligence, just not sure how familar you are with carbs.

 

[maverick0716]

Stock 85 came with a 580 cfm vacuum secondary emissions carb. That 600 dp will do just fine for you (if it really is a dp). About putting a carb spacer on......I don't know about yours but my hood barely closes with a Performer RPM manifold with NO spacer....I even had to trim the air cleaner stud to make it shorter.