Buick V6 Performance Troubles???

Hi, I'm posting this for my father and I'll try and describe the problem as best as possible. We own a 1966 V6 CJ-5 Tuxedo park. The problem is it isn't running well at high rpms. My father says it's running "rich" and we can't figure out why. He says it just doesn't feel like it has any power at high rpms like it should... being a V6 and all. Any suggestions would be nice. Thanks guys

 

What do you consider high RPMs?

 

sounds like the carb or the timing need further adjustment. Another problem might be a restriction (animal nest) in the intake/exhaust

 

My father says in the 2000 rpm range it starts to loose power. He says it feels like it's running lean at high speed but the spark plugs are black as though the engine is running rich. Timing has been checked and double checked. We can't figure this out, need a serious jeephead answer! thanks

 

Has the carb been tuned lately?

 

how much advance do you have on the ignition? mine runs best at 5* advanced.

 

The carb isn't the problem, it was totally rebuilt. Then thinking we did something wrong, our skilled mechanic took it apart checked it, took it apart again and re- checked it. So we know it isn't the carb. How far it is advanced... hmm I'll have to ask my father, it's not in our garage right now so... I'll get back to ya on that one. But thanks for the help guys. Really appreciate it.

 

vacume advance canster advancing the timing??

 

Just a comment. If you are used to a fast reving V8 (especially with an auto trans where the converter will let it spin up) the 225 feels pretty sluggish above 2000 rpm. It is spinning a BIG heavy flywheel and a lot of drive train and big tires in my case. Also they are built for torque, small intake ports and a small carb. These do not lend themselves to quick revs in my opinion. Mine jumps out of the hole pretty quick but then feels a little draggy! (Is that a word??)

 

mine will jump pretty well if i accel at 2K rpm. i did remove the vacuum advance but that was so i could fit the gm hei in. still mileage is about ave for this engine/cj (12 - 14 around stop and go traffic

regarding the plugs being carboned, are they fouled? if so with fuel or oil?
what are your plugs gapped at? how's the coil? i believe that at higher rpm's the coil doesn't put out as much per cyl since the buildup time is less between firings so when the field in the coil collapses (i.e. when the points open) there is less voltage put out to the plugs and a weaker spark.

correct me if i am off base anyone. cause obviously i may be way off base here.

 

is it back firing at higher rpm? when i had points, the nut that controlled the opening of them was rounded and the points were not working properly. anything above 2500-3000 and it would back fire alot. it was lagging power above 2000 aswell because it couldnt run very well with the points messed up. i switched to HEI and it cured everything but the blown motor (which came later) 0=) .