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Discussion Starter #1
87 Caballero, 305, 200-4r, 3.08 rear. Assumption of it being pretty much stock.

So I pulled the top off the carb today, to fix the secondaries, the prior rebuild forgot to hook up the spring, it was just floating, and rerouted some vacuum tubing (two things directly in front of the carb were tied into each other, nothing going to the box on the left fender).

All seemed well and good, started up better than ever before, purred like a kitten. So after warm up cruise in the boonies, I opened her up from a dead standstill, no brakes. 4 second squeel, not bad. Got to @ 3k on the tach, bogged down considerably, got to 4k still kinda gutless, 5k decided to shift into second. Hello, wake up, slammed me into the seat, chirped the tire and took off.

Same deal getting to third, but much smoother shift.

So I'm assuming a shift kit in the trans, no idea why so aggressive 1st-2nd. What bothers me is the 3k+bog down when @ 4k should be max HP.

According to vac guage, at idle I'm pulling 20 at 750rpm.

So, question. Sorry for story. Something not right with the carb still? Timing? It seems very decent at low gas pedal, just really gutless at WOT.
 

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Check easy stuff first, fuel filter, fuel pump, and timing, check vacuum and mechanical advance mechanics. Then you will need to check fuel float level inside of carb and needle valve for something in it. If all else check cat (s) and muffler. I have seen the old cats melt down and plug the muffler.

That'll keep you busy for a while. lol
 

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Torque gets you moving; HP keeps you going. Your torque peak is around 2800 RPM which is about where you landed when you shifted from a 2.74 trans ratio, 3.08 gear at mid 40 mph to 1.57 trans ratio. Did it also bog down at 3K+ in 2nd and 3rd? What are the cylinder compression readings (200+PSI new or 120-PSI old) and is PCV system in good condition?
 

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Discussion Starter #5
You know that little spring on the left side by the adjustment/lock screws to tension the butterfly shaft on the secondaries. It was hanging off the shaft hook, not even on the tensioner screw and the lock screw underneath is torx and was almost all the way out. What I did find is that the shaft binds a little (still, but not as bad now) so wouldn't close the butterfly fully (without a little push) except when the choke vac pulls it closed. I'm thinking the air horn is warped a slight amount.

Yes, it bogs at just over 3k upto almost 4k then clears up, mostly, like it hits HP peak at 4k and then starts dropping off. Happens in any gear, but only at WOT. It was worse before I rerouted the vac hoses, came out of the front of the carb, to the first valve, one to canister, one to second valve, from second valve was looped back to second valve and then back to first valve. Dead end loop. At least now the electronics on the left fender are now hooked up to vac.

I wanna say compression should be good, there's no misfires or knocks or skips or anything to say it's weak before 3k, it will chirp at 1-2nd shift, and supposedly only 126k on the engine, but no guage to tell exactly.

When I pull the air cleaner, there's a small amount of vacuum at the left side pcv tube that goes from valve cover to aircleaner, so I'm thinking that's right and good.
 

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OK sounds like your looking at a carb issue at 3K. I will let the more experts answer. All my vehicles run injection now. Got rid of last carb Elco a couple years ago.
 

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Discussion Starter #7
Heh. Yeah was kinda thinking that. Not sure what the prior owner did to this thing. Think I'll have to Holla at Mountainman and send it to them if they are still rebuilding carbs?
 
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