another n00b question... carb guys! come in!

[MaxTheHooker]

Ok, so as a lot of you know i currently have a carbed 306....

gt40 heads, big ass cam, 670 street avenger, and performer rpm intake...

now, i'm told one of the only things still choking off my set up are my 1 5/8th inch long tubes and my ****ty ass carb with vacuum secondaries. i was told by multiple people to find a new carb with mechanical secondaries and have been looking at the Holley 650 Double Pumpers... now, my question is, would that set up be ok for a street/strip application, or should i save my money for a brand new one of these:

Holley 0-82651 - Holley 4150/4160 Street HP Carburetors - JEGS

or should i get something entirely different? i'm really trying to do this as cheaply as possible because i'm currently fixing up a car that i wrecked to sell it... so if you guys could help a brother out with some good advice, i'd appreciate it!

-Max.

 

[Fast63]

Well, your 1 5/8 longtubes definitely aren't choking your setup. Neither is the 670 street avenger. What's the problem you are having with the carb?

 

[MaxTheHooker]

nothing, i think the car runs fine... but i was told that the vacuum secondary is killing me and is choking off the cars full potential.. i was told to get a mechanical secondary carb, like a holley double pumper. truth or no?

 

[90 lx convert]

Can we get some details? Engine,Mods,Tranny, Gears? What is the car doing or not doing? Mike

 

[89streetbeast]

big ass cam,

now, i'm told one of the only things still choking off my set up are my 1 5/8th inch long tubes and my ****ty ass carb with vacuum secondaries. i was told by multiple people to find a new carb with mechanical secondaries and have been looking at the Holley 650 Double Pumpers

how bigs the cam?. and no, those headers are fine for what mods you have. your carb is fine unless you drag it only, otherwise i'd shoot for mechanical secondaries otherwise vacuum is fine for street. how does the motor rap from dead to XX rpms?. does it stumble or does it do good?. if its fine leave it man. sounds like a good setup.

 

[MaxTheHooker]

well, to be completely honest, the thing is a monster from idle all the way up... (from a dig)... from a roll, she doesn't bog at all... like, she'll accelerate, but then start pulling hard in the later gears.. for instance, forth.. i'll take 4th and punch it at about 45-50 and she'll accelerate moderate, and then just pull real hard in the higher rpms right up until i shift...



i don't know, i just like driving my car.. it seems fantastic to me, the driveability isn't so bad for such a huge cam...

and i couldn't tell you guys what kind of cam it has because i didn't build the motor... the guy who sold me the car told me it was a comp cams x something or other, but i'm positive he was full of ****... i've also had guys tell me that it sounded exactly like an e-cam (but when they told this to me she was idling between 1050-1100 because she's a real bitch at a lower idle - almost impossible to drive at 750)... when i bring down the idle to about 750-800 she'll barely run lol.

YouTube - My 1989 Ford Mustang 5.0 LX

here's a video of the car... it's below freezing outside so it takes a while for the idle to kick down. she kicks down at around 1:09, and even then the car was idling at around 900 or so.


but anyway, back to the issue... i had one of the most trusted street racers around this area tell me that the 670 with vacuum secondaries was choking me real bad, and i could definitely see his point.... i just don't know if it'd be all that worth it to put something like a double pumper on it... would there really be THAT much of a difference? the car pulls real hard as she sits, but if i can get that much more out of it i'd jump at the opportunity, you know?

 

[89notchboy]

the guy whole sold you the car wasnt full of SH$$T by the way ... maybe he just didnt know what cam was in it and was only going by what the previous owner said .. you got allot of car for what you paid ..

BTW .. watch your mouth

 

[MaxTheHooker]

yeah? ya think? i don't know, i hope i did :/.....

and yeah, i'm sorry about my mouth - i tend to cuss like a sailor. i'll try to keep it down

 

[Rick James]

If ''the most trusted street racer around'' told you that those headers and a vac secondary carb is ''choking your engine'' than he is retarded.

 

[lang williams]

I'm no expert but the 670 on a 306 sounds right on to me. I have a reg vac secondary holley 600 on my 5.0 with mild ported gtp heads an crane 2020 came (.530 lift). My bro made the mistake of assuming his motor needed a big carb since it was a race only motor. He picked up a barry grant 850 speed demon an he car bogged like made. He called Barry Grant, told them his set up an they recomended a 650 mighty demon. That was on a 355 sbc with dart heads.