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gregg63

Predator Carb 6000pxi now it works !

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Just thought I would post the results of my Predator Experiment for those that have thought about using one. About 4 years ago I decided to try one on my 389"/351 stroker engine on my street rod. Years ago I raced against alot of guys that had them on dirt stock cars and they seem to work awsome.  Since I had the engine out and had access to the dyno I thought it would be neat to try the Predator. Bought a brand new one off ebay. Well after messing around 3hrs of dyno time, it was a failure, the carb kept going way rich over 5000 rpm and no matter what I adjusted,main mixture screw, idle mixture screw, air damper doors it just went rich and wouldnt make over 530 hp that was with the leanest fuel cam in it. So I got fed up and put holley 750 on and she tuned in to 580hp.

Ok well 4 years later I decided to take a good look at the carb and see what might be wrong with it. Ok here's what I found, the main metering block needs to float on "shouldered" bolts with spring washers on them. the main mixture screw moves the metering block to adjust the mixture. Well apparently when it was assimbled in the factory they didnt check to see that the metering block had clearance enough on the shouldered bolts in order to move. When I tried to adjust the mixture screw on the dyno to lean it down it just ripped the mixture screw nob out of the metering block leaving it in the FULL RICH position. So with a u clamp and two small plastic screws I repaired the ball socket to the metering rod. Then I shimmed the shoulder bolts so the metering block could move and not break the adjuster screw out. 

So I put it on the car yesterday , did the adjustments as per the manual. It Idles way better than the holley, throttle response is dang near as crisp as a mechanical injection. Driving in slow speed and midrange rpm is much smoother than the holley, you can hardly tell that there is a 650 roller cam in it lol. And wow! Wick that throttle and it is right there braking tires loose twice what the holley was. I am curious to see if it will shave off on the 10.30Et at the dragstrip. 30 years off racing experience that I have tells me it will shave off a few 10ths, it sure feels more powerful, we'll see. Has anyone else worked with these carbs and how were your results? 

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just mess'n around i grabbed one very used off ebay, had to do some repairs & fix'n due to the previous owners attempt to do something i can't remember but he just barely missed with a drilled hole. maybe it was a vacuum advance tap? but i found the same as you, crazy responsive like an injection system

01_08_06_1516.jpg

predatorthrottleblades.jpg

predatorbowl.jpg

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Tinman I drilled in vacume advance on mine too. I notice yours has a fuel baffle above the float. Is that something that was an ad on for the Predator? Cause mine doesnt have that plate? I didnt have any problems with fuel slosh on friday when I drove it. I did some hard accelleration tests, but I didnt do an all out warm up the tires and then dump the clutch deal either ya know.

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Heck IDK!

looking at it now it looks like something anyone could make & put in if the grooves are there to hold it.

i searched over the web page but i don't see the bowl baffle listed http://www.predatorperformanceproducts.com/

it's been a long time since i played with it but yeah they are pretty amazing

https://www.pinterest.com/pin/365284219747420428/

 

 

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