Author
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Topic: Somehow I have lost 2 tenths!
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70coupe Gearhead Posts: 357 From: Toronto,Ontario,Canada Registered: Aug 2000
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posted 10-14-2002 01:42 PM
I went through all my numbers over the last few months and my average time is 12.09 at a corrected altitude of 2000'. My last few times out my average is 12.30 at 2000' wind conditions are the same. I've changed the plugs,wires and distributor as mentioned before, so that is out. Next I'm thinking valve springs or cam which have also been mentioned by helpful m&m posters. How should I go about checking the cam? Should I remove it or try to figure it out by checking the valve train? Whats the best way to do this? Thanks, Brian. ps I still have that very small poping sound out the tail pipe at 4000 rpm and over when in neutral.------------------ 351c 4v clsd heads 60'1.619 1/8 [email protected] 1/4 [email protected]
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Rustang1 Gearhead Posts: 110 From: Registered: Nov 2000
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posted 10-14-2002 02:08 PM
If you haven't already I'd pull the plugs (maybe take a quick look at how they're burning), if they look alright, run a compression check or leakdown. If you suspect cam problems a compression check would probably be more effective. Sounds to me like a valve/seat problem.------------------ 1968 Mustang,Clevor,C4 1969 Torino 351C 4spd 1978 F150 460 C6 1978 F150 351W C6
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Moneymaker Administrator Posts: 19704 From: Lyons, IL, USA Registered: May 99
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posted 10-14-2002 02:15 PM
How's your speed? ------------------ Alex Denysenko Co-Administrator and Moderator NHRA/IHRA/SRA member and licensed Superstock driver MCA member# 53321 NHRA and IHRA SS/LA National Record Holder '00, '01, & '02 Fleet of FoMoCo products including 88 ASC McLaren Mustang #28 Professional Manwhore The Barry of BarrysGrrl Quote #1: "I never met a magazine mechanic I liked." Quote #2: "Make sure brain is in gear before engaging mouth!" Quote #3: "If you can't run with the big dogs, stay on the porch!"
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70coupe Gearhead Posts: 357 From: Toronto,Ontario,Canada Registered: Aug 2000
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posted 10-14-2002 02:27 PM
Mph seems to be down by 1 in the 1/4 and .7 or so in the 1/8th.
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steve'66 Gearhead Posts: 6522 From: Sonoma,CA,USA Registered: Mar 2000
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posted 10-14-2002 03:20 PM
How do your 60'ers compare? SteveW
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70coupe Gearhead Posts: 357 From: Toronto,Ontario,Canada Registered: Aug 2000
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posted 10-14-2002 03:45 PM
My 60's are fairly consistant. 1.62-1.63 for most. Best ever of 1.610 I ran an [email protected] about a month ago with a corrected altitude of 1809'. Yesterday,I ran an [email protected] but the corrected altitude was -12'. Thats quite a difference in air. The difference in air temp alone was 80F down to 53F for the 11.99? I should have gained some HP with that air and ran in the neighbourhood of .18-.20 faster.
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Mike_R Gearhead Posts: 151 From: Indianapolis, IN 46237 Registered: Feb 2001
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posted 10-14-2002 04:57 PM
As far as the misfire, Once the ignition has been ruled out, I start looking at the valvetrain. I would pull the valvecovers and check the rocker arms, pushrods, etc. They may either need adjustment or have some sort of problem you're not aware of.
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Fordwiser Gearhead Posts: 217 From: Metamora, Illinois Registered: Dec 2000
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posted 10-14-2002 06:25 PM
MSD rev control chips has been known to go bad, would be a quick and easy test to pull it out and see if it still has the miss, before you tear into the engine. Roger
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70coupe Gearhead Posts: 357 From: Toronto,Ontario,Canada Registered: Aug 2000
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posted 10-14-2002 06:41 PM
Yea, I replaced the chip with another one to see if that would help. NO luck! But thanks, anyways. BrianI will post the results on the weekend when I get a chance to get at the motor.
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