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Author Topic: Compression Test
Frank Todaro
Member

Region: Ohio Valley Region
Car #: 35
Year : 1999
Posts: 170
Status: Offline
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Does anyone know what the base line compression in Pounds per Sq. inch would be for a 1999 1.8.

My second question. my spark plugs are burning white or close to it maybe a tint of light brown but vary white. Is that good, bad or Ugly. Can it be to hot? The water temp runs about 210 when itís real hot out.

I was two seconds slower at Mid Ohio this weekend, I am hoping its something other than me.

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Frank
Member: No Pain Racing

ChrisA
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Year : 1999
Posts: 197
Status: Offline
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209-psi is "standard", which I take to mean new.

I went one step colder on plugs and they look like they are burning right. The OE temp range also burned white on my car under track usage.

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Chris

"Nothing can be simple. Everything's got to be a pain in the ass." - C. Adams

Frank Todaro
Member

Region: Ohio Valley Region
Car #: 35
Year : 1999
Posts: 170
Status: Offline
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Here is the compression results. How bad is it?
#1 185
#2 158
#3 168
#4 178

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Frank
Member: No Pain Racing

ChrisA
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Year : 1999
Posts: 197
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Hum, those don't look good. The spread between 1 , 4 and 2, 3 is pretty big. The test should be done with the car warmed to operating temp and throttle open. If that wasn't the case, do them again. If it was, next you should do a leak down test.

Heading off to WGI tomorrow. Weather is looking good. Hoping to learn the track better and avoid the Blue Bushes. We got 7 onboard. See you guys at VIR in Sept. Let me know what you find out with the car. I hold positive thoughts.

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Chris

"Nothing can be simple. Everything's got to be a pain in the ass." - C. Adams

38BFAST Verified Driver
Member

Region: Waterford Hills
Car #: 38
Year : 96
Posts: 348
Status: Offline
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time for a leakdown test to find out if you need just a head or a lower end

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Ralph Provitz
#38
2008 WHRRI SM Champion
2008 WHRRI Top 10 Overall
V2 Motorsports, Race support, Data Dude

Frank Todaro
Member

Region: Ohio Valley Region
Car #: 35
Year : 1999
Posts: 170
Status: Offline
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I will redo the test because it was not warmed up first and I did not have the throttle open. Sorry, I will repost tonight.

--------------------
Frank
Member: No Pain Racing

Frank Todaro
Member

Region: Ohio Valley Region
Car #: 35
Year : 1999
Posts: 170
Status: Offline
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OK lesson #2 You need to do this hot with the throttle wide open Look at the difference in the results from above. This looks much better and not so urgent on a new motor
#1 205
#2 179
#3 190
#4 196

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Frank
Member: No Pain Racing

Johnny D Verified Driver Made Donation to Website
Hot Member

Region: SFR
Car #: 88 SM
Year : 99
Posts: 367
Status: Offline
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Hey Frank,
If you ever end up using this or something like it, I'd love to see your results.

http://www.restoreusa.com/

J~

38BFAST Verified Driver
Member

Region: Waterford Hills
Car #: 38
Year : 96
Posts: 348
Status: Offline
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quote:
Originally posted by 38BFAST:
time for a leakdown test to find out if you need just a head or a lower end

Hole #2 has some issues

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Ralph Provitz
#38
2008 WHRRI SM Champion
2008 WHRRI Top 10 Overall
V2 Motorsports, Race support, Data Dude

Dave Lewis
Member

Region: detroit
Car #: 17
Year : 1991
Posts: 293
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26 psi difference. FSM says 28 max. But I agree with Ralphie.
If you are using a Harbor Frieght type leakdown tester it wont give you an accurate reading for the rings. The pressure is so low it probably wont expand the rings.

   

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