4150 problems

Joe73 wrote:Mechanical secondaries, correct?  Probably dumping too much fuel at too low of an rpm.  That coupled with it wanting to die when braking sounds like carb tuning is required.  Did you set up all 4 of your idle screws with a vacuum gauge to get you close?  What cfm is the carb?

Joe73 wrote:Carb size is good but I think you would always bog when jumping on it at a low rpm.  The rear gear ratio is not helping the matter.  I prefer a vacuum secondary for the street.  But guys also love mechanical on the street.  I sold my 650 dp in exchange for a 750 vacuum thats going on my new motor.

Anyway.  how's the timing??  Do you have it set at a total of 32-36 when all in?  How much timing is the vacuum advance giving you?  Whats your initial timing?  Did you play with the weights to it all in ?  At what rpm?  

Joe73 wrote:Carb size is good but I think you would always bog when jumping on it at a low rpm.  The rear gear ratio is not helping the matter.  I prefer a vacuum secondary for the street.  But guys also love mechanical on the street.  I sold my 650 dp in exchange for a 750 vacuum thats going on my new motor.

Anyway.  how's the timing??  Do you have it set at a total of 32-36 when all in?  How much timing is the vacuum advance giving you?  Whats your initial timing?  Did you play with the weights to it all in ?  At what rpm?  

Joe73 wrote:Ok,  your timing is where it should be.  While power shifting your rpms are high so you wont have much of a problem.  I think its your rear axle ratio hurting you.  

JF74chevelle wrote:

Joe73 wrote:Carb size is good but I think you would always bog when jumping on it at a low rpm.  The rear gear ratio is not helping the matter.  I prefer a vacuum secondary for the street.  But guys also love mechanical on the street.  I sold my 650 dp in exchange for a 750 vacuum thats going on my new motor.

Anyway.  how's the timing??  Do you have it set at a total of 32-36 when all in?  How much timing is the vacuum advance giving you?  Whats your initial timing?  Did you play with the weights to it all in ?  At what rpm?  

Also, timing is 18 initial w/o VA hooked up, then 36 all in at 2700 with VA hooked up. I have one lighter spring and one heavier spring on the distributor weights.

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Bolt them on and go.
You can send them your carb for rebuilding,if you want to keep it 100% original.