Performance drop ?
Thread Starter
Team Owner
Joined: Dec 2012
Posts: 30,427
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From: Outside the Quick Stop N.J.
Performance drop ?
O.K. here is one for all you higher mielage guys out there. Have you noticed and drop off in performance at 100k, 150k etc ? I have a long way to go, with only 3k on the new GS (winter stinks) but was wondering how long these engines can go before their age can be felt.
Team Owner
Joined: Apr 2008
Posts: 31,738
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From: Middle TN by way of KY, OH, VA, IL, CA, FL, NY, SC, HI
No drop felt as of 77K miles in mine.
I'm thinking you would have to have some significant degradation, e.g.; clogged fuel injectors, ignition wire dielectric strength breaking down, severe piston ring wear, before starting to feel any real noticeable drop by seat of the pants.
By dyno over time would be interesting, but have not read where anybody has done this.
I'm thinking you would have to have some significant degradation, e.g.; clogged fuel injectors, ignition wire dielectric strength breaking down, severe piston ring wear, before starting to feel any real noticeable drop by seat of the pants.
By dyno over time would be interesting, but have not read where anybody has done this.
Team Owner
Joined: Sep 2005
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From: Big Bend Country, TX
St. Jude Donor '06-'07-'08-'09-'10-'11-'12-'13-'14-'15- '16-'17-‘18-‘19-'20-'21
NCM Lifetime Member
Over 40k on my 18 mo old '11. I chunked the OE air filter at 30k and ran 1 can of Chevron fuel system cleaner through it. That's it. Car pulls and feels stronger than when new. I'll change the plugs at 75k. Just buy good gas is all I can suggest and do the required maintenance.
Instructor
Joined: Nov 2010
Posts: 162
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From: Indianapolis Indiana
After working on aircraft engines, I can say that it takes considerable compression loss before it shows up in horse power. I agree with the others that in most cases a performance drop would be due to injectors or tuning before anything else. Detonation margin decreases with oil usage, but it takes a lot of oil usage to get there. Seriously doubt 100k miles would show any loss at all.
after 200k you would probably run into valve guide or seat issues first.
after 200k you would probably run into valve guide or seat issues first.
Team Owner
Joined: Apr 2008
Posts: 31,738
Likes: 2,376
From: Middle TN by way of KY, OH, VA, IL, CA, FL, NY, SC, HI
After working on aircraft engines, I can say that it takes considerable compression loss before it shows up in horse power. I agree with the others that in most cases a performance drop would be due to injectors or tuning before anything else. Detonation margin decreases with oil usage, but it takes a lot of oil usage to get there. Seriously doubt 100k miles would show any loss at all.
after 200k you would probably run into valve guide or seat issues first.
after 200k you would probably run into valve guide or seat issues first.
I had not thought about poor valve guide/valve seat sealing.What about carbon buildup fouling? Any effect?
Instructor
Joined: Nov 2010
Posts: 162
Likes: 0
From: Indianapolis Indiana
What about carbon buildup fouling? Any effect?
Carbon buildup can cause detonation to occur earlier than usual, but with the electronic engine controls, and top tier unleaded fuel these engines stay very clean.
Carbon buildup can cause detonation to occur earlier than usual, but with the electronic engine controls, and top tier unleaded fuel these engines stay very clean.
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