GT350Stang

I want to get GT-40P heads, E-303 cam, Edlebrock performer intake, and bbk longtubes with flows. I have a 600 cfm holley on it right now and it runs alittle rich because the stock one was a 550 cfm. i also have MSD wires, coil, and dist. do i need to buy a bigger carb. to put the stuff on that i want to? and remember the word gas mileage when you respond

birdman076

If you want gas mileage, go with an Edelbrock carb. If you want performance stick with the Holley lol. I would honestly say to get the most out of the combo your planning a 650 double pumper, but if its a daily driver I would go with the 650 or 700 Edelbrock. You may be able to get by with the 600 but in all honesty its not really a performance carb, it was meant and marketed as a universal replacement. You could jet it up if its not enough, and if you dont need a choke mill the air horn, rumor has it that is worth 50cfm.

BigMg

Dude on a 5.0 a 600 is plenty big, sence you want gas milage. If you want to have black smoke out the tail pipes and really dirty exhaust go bigger but you wont get any more power. Go with the holly street dominator 600 cfm vac secondary and if you are not happy with how much gas your getting you can jet it up a little and play with the secondary spring.


BigMg

GT350Stang

Ok so i should get a 600 cfm street dominator? or could i just stick eith the one that i have and just do a rebuild kit with a jert kit on it if i ned it and it would act the same?

JD1969

Lets get a couple things straight here. 1. you are not running rich because you went to a bigger carb, it is out of adjustment for your combination, any time you change somthing the carb will need to be re-jetted to take advantage of the new mod. 2 When picking out a carb you need to look at the CFM needs of the engine "jetting up" a carb that is too small will not help you. Luckly I think the carb you have will be fine, rebuild it and get it tuned right for you combination, the NUMBER one mistake people make when picking a carb is to go too big, a 600 cfm vac. secondary will be just fine on that 302. Also contrary to what some people may say a properly set up Holley will get just as good of milage as any other carb out there, the problem with Holley carbs is that there are alot adjustments and people like to fiddle with them and this will result in poor milage. There have been tons of books written on the Holley carb, go to Borders and buy a couple they are worth it and you will have all the info to help you pick out and work your carb.

vfast

and if you need more flow from the 600 just mill the air horn or put on a stub stack.....the 600 come out the box as a general carb..you need to adjust stuff like power valves if you have lower than stock vacuum, different sec springs or even a faster ramp cam on the throtle plate..or just need bigger sqirters..there is so much to adjust to tailor to what you need....the double pumpers are nice as if the carb is too big you don't have the bogs because it dumps fuel to not uncover the problem......if you need gas milage drop down a jet size or 2.....I used to run 1 carb during the week for mileage and a hugh one on the weekend for hp

GT350Stang

ok so with the heads, headers, intake, and cam you think that i should be fine with that 600 cfm?

vfast

yes..just adjust it