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  #1  
Old 05-31-2000, 05:12 AM
RDemon RDemon is offline
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Question

I have a 340 Demon and am having a lot of problems with the right cam. I just put a Hughes Engines cam in it and it is dead off the line and slowed down from 8.30's to 8.50's. I have x heads not ported. I am running a single plane intake now but am thinking about trying a dual. I also have a 750 Holley Race carb. Anytime i try a cam with high lift, i slow down. I am new to this so i would greatly appreciate any information. I did try a mopar performance 508/292 and it killed the car also. When i bought the car the 340 had a 25 year old crower cam in it and it has given me the best times but is worn out. What is better with a 340, more lift or more duration? Thanks
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  #2  
Old 06-01-2000, 05:11 AM
moeflo moeflo is offline
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Give us as many details as you can, Old cam specs, your converter, etc. Somebody here will spot your problem. All I can add at this moment is those old heads are horrible on exhuast. Remember all the trash talked about 351c exhuast ports? You are about -40 cfm of that.
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  #3  
Old 06-01-2000, 05:29 AM
RDemon RDemon is offline
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Arrow

1971 340 bored 40,
x heads with 2.02 1.6 new perf. vavle job,
torker 2 340 single plane intake,
4.10 gears, *also have 4.56*
25 year old crower cam with specs not available at all. They don't even list the part number is what came out of the car and what has run best in it> The NEW cam is a Hughes Engines 3844... 237/244 @50, 286/290 advertised, 535/540 lift, GER 3500 Stall,
put the new cam in and went from 8.37 to 8.57 so HMMM... DEAD off the line also. There has to be something going on here, the car has always been slow off the line with never better than a 2.00 60' time. Thanks Guys

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Old 06-03-2000, 03:24 AM
AJ AJ is offline
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I think that the problem is not with the cams you have been trying, but more with the GER converter. I have never heard anything good about their products except for the price-but-you get what you pay for!! Your cams are good ones. AJ
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  #5  
Old 06-03-2000, 02:28 PM
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Leigh Leigh is offline
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AJ's on to something. You probably need a little more converter. Depends on your useage for this vehicle, but a 340 with 727 needs a lot more flash than most people agree on. I always liked p4120655 for a mechanical setup. Turbo Action 4400 or 4600 seemed to be the ticket. Like I said though, it'll be a terrible street deal.
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  #6  
Old 06-04-2000, 12:04 AM
RDemon RDemon is offline
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I drive the car on the street every weekend, and the cam is hydraulic, so i wouldnt want this. I did well with this converter and the old crower cam, so i dont think it is the problem.>> any other ideas?

Quote:
Originally posted by Leigh:
AJ's on to something. You probably need a little more converter. Depends on your useage for this vehicle, but a 340 with 727 needs a lot more flash than most people agree on. I always liked p4120655 for a mechanical setup. Turbo Action 4400 or 4600 seemed to be the ticket. Like I said though, it'll be a terrible street deal.
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Old 06-04-2000, 03:08 PM
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Leigh Leigh is offline
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Go back to basics. You must have missed something. Everything has a cause/effect. If you aren't sure of the cam centerline, for example, find someone who can do it for you. There is no magic solution other than sytematic, step by step diagnosis. Literally millions of this car/engine combo have worked outstandingly, with much wilder cam/converter/fuel systems. Turn over every stone, the answer is there in front of you. I recall a bumper sticker many years ago at a race track. "I accept all items for free except advice" Something to ponder. Happy hunting, its what seperates us from the masses.
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  #8  
Old 07-26-2000, 11:21 PM
wedgehead wedgehead is offline
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I was wondering what you meant by the Crower cam that came in the car being worn out. Did you wipe a lobe or something? Was this a solid lift cam? With the 340 and a 727 you need to be very careful with duration @ .050 numbers and make sure to match your converter with the camshaft. With stock X heads you dont't want to go more than 252-255 @ .050 and with this you'll probably need a true 4000-4200 stall. This converter should flash at least 5000 and lock at 4000-4200. Also your ignition will need to have a quick advance, start at 900 rpm and be all in about 2000 rpm. You'll need light advance springs for this. Good luck, Wedgehead
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