carb sizing

tayzoid1 · 10-12-2008, 09:21 PM

i have a carbed 302 f303 cam edelbrock 289 performer intake and i was wondering i have a 600 holly w/ vacum secondaries and i was wondering if i put a holley 750 double pumper w/ mechanical secondaries would it be too much carb or would it make the car stronger this is my first performance carbed car so not really sure
thanks
taylor

92 lx · 10-12-2008, 09:31 PM

i would go with a 650 double pumper w/ mechanical secondaries if u didnt already have the 750

03slobra · 10-12-2008, 10:13 PM

I think the 750 will be a little much.If its a street motor I'd go with a 570 street avenger.I've put one on a 351 and 302 worked nice.If not go with the 650 or 600.

qkjuicedpony · 10-13-2008, 04:28 AM

the 650 will be as big as you will need.But like said look for the 570

QWKSNKE · 10-13-2008, 06:18 AM

stock heads? If so, stick with the 600

tayzoid1 · 10-13-2008, 04:31 PM

ohh ok no i dont already have the carb it has the hooley 600 vac 2nd i was going to throw on my buddies 750 dp for a day when i go to the track but if its too much its too much

thankjs
taylor

Craig K. · 10-14-2008, 01:00 PM

750 is way to much for your combo.

I have a 650 mechanical secondaries on mine and it runs around 12.1:1 air fuel (don't know jet size) in a 10:1 compression motor and a .500 lift / 228 duration cam.

I would think 600 CFM would be good for your application

LeeH · 10-14-2008, 07:52 PM

I hate the Street Avenger carbs, Give me a 4150/4160 any day! The general public cant spell or tune a Holley let alone choose the correct size or type. The vac sec carbs are proven performers and provide the best balance for daily driven street/strip car, The Holley 1850(600 vac sec) is an excellent choice, What you give up with a larger CFM carb is bottom end Tq. You want a carb that will provide good throttle response(smallish primary) without being a restriction up at peak engine speed, The way to check carb size is to check engine vacuum below the throttle plates at full throttle(while making a pass) and if you show more than a few inches of vacuum at full thottle you need to step up.

10-12-2008, 09:21 PM	#1
tayzoid1 5.slo stanger Join Date: Jan 2007 Location: oxford alabama Posts: 735	carb sizing i have a carbed 302 f303 cam edelbrock 289 performer intake and i was wondering i have a 600 holly w/ vacum secondaries and i was wondering if i put a holley 750 double pumper w/ mechanical secondaries would it be too much carb or would it make the car stronger this is my first performance carbed car so not really sure thanks taylor __________________ no mustangs anymore but i do have a 1jz swapped 83 supra

10-12-2008, 10:13 PM	#3
03slobra Senior Member Join Date: Nov 2006 Posts: 488	I think the 750 will be a little much.If its a street motor I'd go with a 570 street avenger.I've put one on a 351 and 302 worked nice.If not go with the 650 or 600. __________________ Preston 1947 mercury 2door coupe 331w/tko 600 project 2003 f350 5in lift 6.0 with upgraded stuff!!!

10-13-2008, 04:28 AM	#4
qkjuicedpony Dayuuuuuuum!!!!! Join Date: Dec 2004 Location: Dallas GA Posts: 2,933	the 650 will be as big as you will need.But like said look for the 570 __________________ 86 Mustang Gt......Mods piling up in my garage. 07 F350 dooly.....Tows my fifth wheel

10-13-2008, 06:18 AM	#5
QWKSNKE 3v's are slow Join Date: Dec 2004 Location: Here and There Posts: 17,152	stock heads? If so, stick with the 600 __________________ 2009 Porsche Carrera S 2008 ///AMG C63.. Eurocharge Tune. RIP 2019 AMG GLC43..wife's 03 F250 SD.. Edge Evo, AFE Stage 1 CAI 08 GT. JBA axle back, FRPP springs, FRPP swaybars.. daughter's 01 Cobra vert... wife's I need a new toy

10-13-2008, 04:31 PM	#6
tayzoid1 5.slo stanger Join Date: Jan 2007 Location: oxford alabama Posts: 735	ohh ok no i dont already have the carb it has the hooley 600 vac 2nd i was going to throw on my buddies 750 dp for a day when i go to the track but if its too much its too much thankjs taylor __________________ no mustangs anymore but i do have a 1jz swapped 83 supra

10-12-2008, 09:31 PM	#2
92 lx Member Join Date: Dec 2006 Location: speedmont Posts: 53	i would go with a 650 double pumper w/ mechanical secondaries if u didnt already have the 750

10-14-2008, 01:00 PM	#7
Craig K. Nothing new here Join Date: Dec 2004 Location: Senoia, GA Posts: 2,990	750 is way to much for your combo. I have a 650 mechanical secondaries on mine and it runs around 12.1:1 air fuel (don't know jet size) in a 10:1 compression motor and a .500 lift / 228 duration cam. I would think 600 CFM would be good for your application __________________ 1974 Triumph TR6 1985 Monte Carlo SS 1986 Mustang GT 2011 KIA Optima GTS

10-14-2008, 07:52 PM	#8
LeeH Senior Member Join Date: Dec 2005 Location: The conservative underground Posts: 341	I hate the Street Avenger carbs, Give me a 4150/4160 any day! The general public cant spell or tune a Holley let alone choose the correct size or type. The vac sec carbs are proven performers and provide the best balance for daily driven street/strip car, The Holley 1850(600 vac sec) is an excellent choice, What you give up with a larger CFM carb is bottom end Tq. You want a carb that will provide good throttle response(smallish primary) without being a restriction up at peak engine speed, The way to check carb size is to check engine vacuum below the throttle plates at full throttle(while making a pass) and if you show more than a few inches of vacuum at full thottle you need to step up. __________________ 89LX Hatch 89LX Coupe 89GT 90GT 93GT