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Discussion Topic:
power deficiency?
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ermine white |
04-01-2023 @ 10:56 AM
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Member
Posts: 5
Joined: Apr 2023
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I recently purchased a 35 5 window coupe with its stock 221, going up the bigger hills in my area it won't maintain the 45 mph speed limit (drops down to 35 or so) is this normal with these 85 hp cars, or am I dealing with a tired or poor running engine?any input would be greatly appreciated.
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1931 Flamingo |
04-01-2023 @ 12:37 PM
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Member
Posts: 388
Joined: Nov 2019
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Are you downshifting?? Paul in CT
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carcrazy |
04-01-2023 @ 1:31 PM
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Senior
Posts: 1667
Joined: Oct 2009
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There are several things that affect the amount of power available from a stock engine. Among these are the rear axle ratio, the overall gear ratio and altitude. If you live in the Denver or another area significantly higher than sea level, you will experience a reduction in power. You should be able to shift down to second gear to provide enough power to maintain 45 MPH at areas around sea level.
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MG |
04-01-2023 @ 3:30 PM
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Senior
Posts: 1260
Joined: Nov 2009
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Clutch slippage is more than likely the culprit...
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ermine white |
04-01-2023 @ 4:05 PM
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Member
Posts: 5
Joined: Apr 2023
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ok thanks, with no tach not sure how to gauge how high to rev it without blowing it up!
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carcrazy |
04-01-2023 @ 8:00 PM
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Senior
Posts: 1667
Joined: Oct 2009
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Making the following assumptions: your tires are the stock 6.00X16 size with an aspect ratio of 90%, your rear axle ratio is the stock 4.11:1, your 2nd gear ratio is 1.60:1 and you don't want to rev your engine over 3800 RPM (the power peak), 2nd gear is safe for 46 MPH. If you have the stock 2.82:1 1st gear ratio, 3,800 RPM engine speed in 1st yields 26 MPH. Your top speed in 3rd gear at 3,800 RPM, providing your engine has enough power will be approximately 74 MPH.
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ermine white |
04-02-2023 @ 8:01 AM
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Member
Posts: 5
Joined: Apr 2023
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thanks for your input, yes, all of your assumptions are correct,the information you provided has been very useful,thanks again.
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JayChicago |
04-02-2023 @ 11:45 AM
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Member
Posts: 484
Joined: Jan 2016
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I'm thinking that this low power issue could be due to so many different things, that we on this forum can't really give any meaningful advice. My only advice is to join your local Regional Group, have someone with experience drive with you on those hills.
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ermine white |
04-02-2023 @ 11:57 AM
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Member
Posts: 5
Joined: Apr 2023
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Thanks for the advice,I will do so.
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CharlieStephens |
04-02-2023 @ 12:09 PM
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Senior
Posts: 893
Joined: Oct 2009
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Check to be sure you are getting full travel on the throttle, sometimes the linkages get bent. Charlie Stephens
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