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i'll be removing my carburetor to detail my engine compartment. i might take that opportunity to have it rebuilt. how hard would this be to do myself? i can have it done for $125 and i would gladly pay that to not have trouble with it later. is there anything that could be done to the carburetor during the rebuild to improve performance? by the way, the motor is stock and the carburetor is the original autolite 4300.

also, would a carb spacer improve my performance? the motor quits making power at 4000 and some have suggested that it is not getting enough fuel to rev past that point. would a spacer improve this? thanks.
 

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From what I remember reading a while ago, 4300's are pretty complicated and are more of an emmissions carb. They're not that big either, under 500 cfm's, I think more like about 440 cfm's. Pay to have it done by a reputable shop.

I don't the spacer will do anything. To add my $.02, I'd store the 4300 and put the $125.00 toward a Edelbrock 600 cfm carb. These are fantastic carbs and run really well right out of the box. I've used Holleys before, but this carb is really sweet, you won't go wrong!
 

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ok a engine detail could be done around 50-100 very nicely eastwood sells the right paint for everything and a carb spacer would improve your proformance slightly but a bigger carb (cfm) and free flowing exhast. when you upgrade top end proformance usealy will low the low side, like for exaple if you use large valves with a tunnel ram or single plane intake and large tube headers and the right cam then you will get alot of hp in the 4000 up range but lose alot of it in the low rpm range and some idle and driveablity problems. a engine rebuild can cost 500(halfassed) to 1500(relyable) even more for a profromance build up then you have to worry about tranny and rearend build up too. but now im just getting off track
 

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I have put a spacer on recently, and can tell you that the performance difference is there, but it isnt really noticable without measurement (dyno/qtr mile). What is noticable however is the fact that the car never has problems starting once hot anymore, and a (very) slight milage improvement due to the fuel not boiling anymore. For around 5-15 US I'd say its worth it for a 1/2 in phenolic spacer.
 

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Spacer improve fuel atomisation (mixes the air/fuel better) and improves throttle response. Would make little difference with top end. Rejetting the carb would help the top end, but replacing the carb might be easier. The spacer is easy to install.
 

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A phenolic spacer will work to isolateyour carb from engine heat and thus keep your carb and the fuel in it cooler, and that will help performance under hot conditions.

I agree with Huskinhano though - while I love my 4100 for my 289, for your 351 I'd upgrade to a slightly larger carb. The Edelbrocks have lots of fans. Dickson
 

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I noticed a noticable improvement in throttle response with a 4-hole 1" spacer on my old 302.
 

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While I have to agree with everyone on the spacers and especially the phenolic spacers. However, in his particular case with al things being stock, I don't think it'll make a worth while addition in his case, other then heat reduction. Sorry for not clearifing that.
 

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I got maybe (?) good news for you. I have a Edelbrock 600cfm carb Electric choke I had bought with an RPM manifold for my old 302. 302 has been out for about 4 months now, and the carb only has a few hundred (not even) miles on it. I'd be glad to part it to a fellow VMF'er for $150 (okay price?). Also, if you need the manifold, I can pitch that in for cheap too!

Let me know!
 
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