500cfm carb on 200ci

[Anonymous]

ok I know its too big.

but will it actually work? I got it on my parts car which has a xflow 250 in it. going out and buying a 350 would break the budget, so its either this or a stock single barrel!

 

[rbohm]

8) yes its too big, but yes it will work. you may have some drivability issues, and fuel economy issues, but it will work ok.

 

[Anonymous]

Just eBay the 500cfm and buy a 350cfm with the money. I bought my Holley 350 on eBay brand new in the box for $230 shipped. You can definetly sell the 500cfm for that much or more!

 

[Lazy JW]

Certainly not optimum but properly tuned it will run just fine until you open the throttle too far for the available airflow at that moment. Very few engines actually operate at full throttle all the time, so obviuosly it can be made to work. Maybe modify the linkage so it won't open all the way.
Joe

 

[Anonymous]

What's the engine like your going to put it on? Stock or hopped up??

I always say 350 cfm Holley for a mild engine and a 500 cfm Holley for a wild engine!

I've ran a 500 cfm Holley on mine for the past 3 years and have had no drivability problems with it.

Later,

Doug

 

[Anonymous]

If you use the 500, change the power valve to a 4.5 or 4.0. Your manifold vacuum will be pretty low, so the power valve in a stock 500 will try to open 'way too soon, causing you big tuning headaches and bad, REALLY bad MPG.

 

[wsa111]

I agree with Doug, use the 350-7448 on a mild or slightly modified engine.

Use a 60 main jet & set your idle air fuel ratio in the 13.5 area.

With the 500-4412 this carb should be used on a direct mount to the log & use a 68 main jet, 6.5 power valve & insert a .010 wire in the PVRC-power valve restriction orifice. Doing this will give you a 14.7 cruise air fuel ratio & a 12.3 full throttle air fuel ratio. The idle should be in the 13.5 area.

All these tests were run using an inovate lm-1 air fuel ratio tester. If you tune with a vacuum guage you are just wasting your time & fuel miliage.

Unless you use this air fuel ratio tester your full throttle air fuel ratio is in the 11,s way too rich.

Modern electronics sure beats the seat of the pants test method. William

 

[Anonymous]

well its not going to be over the top wild, but I was considering this cam..

Wade 1147
232ex/226in duration
.474/.456 lift

nice job on the 500 install wsa111, and thanks for the info. you dont have any photos of your log manifold modifications do you?

 

[Anonymous]

by the way, what are the specs of your cam mustang geezer?

 

[Anonymous]

by the way, what are the specs of your cam mustang geezer?

I dont have the cam card handy but IIRC, its .480 lift 274 duration but I'm running 1.6 ratio rockers so its actually a tad over 500 lift.



Later,

Doug

 

[66Sprint6]

Havnt been on here in FOREVER, but I ran the 500 no problem with headers, small head work, duraspark and thats about it. If you tried to punch it off the line it would sometimes stall, but eventually we worked that out...fun carb I think!! 350 might be better for light mods, but if you have the 500, put it on and get it runnin!!!!
Matt