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Old 05-17-2003, 05:04 AM
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Unhappy Help New engine low power !!!!!!!

HI,
I Have a Chevy 350 in a jeep wrangler. I Had the machine work done to a 76 L48 vette motor. Valves were done and cylinders were honed. I replaced the pistons with new flat tops and installed a rv cam with new lifters. My intake is a edelbrock preformer. My exhaust manifolds are older ram horn style with full dual exaust and 40 series flowmasters.
The tranny is a 700r4. I also still have the transfer case. My rear end gearing is 4:11.
The Problem is when it is not in gear it runs great, revs up with no hesitation. But put it on the road and the silly thing has no power. It will not even break the tires loose. This entire thing only weighs 4000lbs.
I have changed from 4 different carbs 2 being brand new(holley 600 &750) and also 2 distributors and a new summit racing 50,000 volt coil and 8mm wires.
There is not one thing on this motor that is not new. I am lost this time. A friend said that the only thing he could think of was maybe I got a bad cam. Thinking that the cam has improper lobe grinding.
Any ideas would be a great help.
Thanks in advance
Rob
Blueyedwolf71@yahoo.com

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Old 05-17-2003, 05:53 AM
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go over your spark timing and fuel flow carefully, if you find no problems, then I have to ask have you slipped it down in low range? a friend had a small block in a jeep, in high range it was a slug with 35 inch tires and 2.35 gears, he slipped it in low range and it blasted out of the hole like a bat out of hell. he later had some 3.73`s installed and end of problem. the wranglers are extremely high geared, i think 2.73`s were optional, and if the tires are taller than stock, that makes the problem that much worse. one way to check, is to see how far in MPH you can wind it up in first gear, if you can wind it way up there you don`t have enough gear.
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Old 05-17-2003, 06:02 AM
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I have double checked the gearing. This was a 4cyl jeep stock those have 4:11 gearing. The 6cyl jeep had either 3:54 or 3:73. I have a digital timing meter and the timing is at about 16 btc. On the fuel flow thing I have gone with a new stock pump and a carter 7 to 9 psi electric pump and also the stock jeep FI pump which is about 35psi (used a regulator with it). I was also thinking that I was not getting enough voltage to the distb so I put the hot wire directly to the battery. Still no joy
Thanks
Rob
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Old 05-17-2003, 06:45 AM
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You say that your initial timing is set at 16 degrees BTDC. Is this with the vacuum advance hooked up? Your timing (initial and/or total) should ALWAYS be set with the vacuum advance line disconnected and plugged. Re-connect the line after you have set the timing. If you have your initial timing set at 16 degrees BTDC with the vacuum line connected you will actually have your ignition retarded. Thus the low power. You will also experience "glowing" exhaust pipes and more than likely your coolant will be on the "Hot" side.

[ May 17, 2003: Message edited by: Frisco ]

[ May 17, 2003: Message edited by: Frisco ]</p>
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Old 05-17-2003, 07:09 AM
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you might check to see if your timing marks are correct, are you sure the cams in perfect time? just a thought
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Old 05-17-2003, 08:08 AM
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Yes my timing was done with the Vacuum advance was disconnected and pluged. I am going to pull the cam out and try that alley. We just put a third distb coil and wires on it with the same results. I guess it has to be in the cam. It runs great driving with out your foot in it. as soon as you give it gas it seems like it will not burn it.
Crossing fingers
Rob
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Old 05-17-2003, 03:52 PM
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Ok I figured it out.
I had the timing marks on the cam 2 teeth off. I don't know I did it. Surprisingly it idled great but under a load it would not get out of its own way.
Now it will roast the one tire from a stop.
Thanks for the responses
Rob
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Old 05-17-2003, 08:37 PM
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just to let you know and all other new members, that posts like this last one where we all get to find out what the hell the problem was and that it is fixed, are the best posts of all to read about. thanks!
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Old 02-07-2004, 05:26 PM
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Chevy 350

Im new here, I have a chevy 350. We built a motor top and bottom. Put it in the truck and had a problem. We put in an RV cam and I think that's where IM having trouble. I still have all the emission system and the Computer control working in a 1991 setup with a throttle body . The problem is LOW power and small back fire on take off. Also low power between gears until the RPM builds up. Some of the power comes back to normal after it gets up to TEMP. but the low end is still lacking. Top end is much better. I timed the thing at TDC with the computer wire unplugged. Then when I plug it back in it jumps to 22 BTDC. I have no idea where I should start with the timing. Or if the Computer or emission system is overriding no matter what I do. Any help or ideas? Email or post I'll try and find my way back here.
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