Diameter of stock cat pipe - '89 951
#16
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Originally posted by Flight_951
Bump.
Maybe someone can take a glance at their 951 and see what if anything is attached to the little brown vacuum port in the photo above (left side of photo). It would help me out greatly. TIA
BTW, the location is top of engine in the back, behind/under intake manifold. Can see it best leaning over from driver's side.
Bump.
Maybe someone can take a glance at their 951 and see what if anything is attached to the little brown vacuum port in the photo above (left side of photo). It would help me out greatly. TIA
BTW, the location is top of engine in the back, behind/under intake manifold. Can see it best leaning over from driver's side.
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Ron
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Thanks, I verified in the factory manuals that the valve without the tubes is the "timing valve" which I guess is the same as the cycling valve. I thought (or hoped!) that was the answer to my problem but nope.
Just an update for reference... I had the car at the shop today and we measured the temp of the exhaust pipes before and after the cat. Warming the car up for a couple minutes produced a temperature over 100 degrees hotter at the inlet before the cat vs. the outlet pipe after the cat. Therefore the cat appears non-functioning and partially plugged.
Although the car failed the emissions test across the board this time, it has had a high NO ppm number for the past couple years. This may indicate high combustion temps due to a failing cat. (This was even before I installed non-stock chips which raise the timing.)
Over the past couple weeks the coolant temp has started increasing more than normal too.
The space provided for the cat or its replacement is pretty tight and the stock cat is rather long so we elected to not try to install a universal replacement in there.
So... I just ordered the SFR 3" test pipe with optional cat section. In the next couple weeks, I should have the product and have it installed. The shop has a dyno so I am considering running the car with and without the cat to see the hp difference.
Thanks all for the info!
Just an update for reference... I had the car at the shop today and we measured the temp of the exhaust pipes before and after the cat. Warming the car up for a couple minutes produced a temperature over 100 degrees hotter at the inlet before the cat vs. the outlet pipe after the cat. Therefore the cat appears non-functioning and partially plugged.
Although the car failed the emissions test across the board this time, it has had a high NO ppm number for the past couple years. This may indicate high combustion temps due to a failing cat. (This was even before I installed non-stock chips which raise the timing.)
Over the past couple weeks the coolant temp has started increasing more than normal too.
The space provided for the cat or its replacement is pretty tight and the stock cat is rather long so we elected to not try to install a universal replacement in there.
So... I just ordered the SFR 3" test pipe with optional cat section. In the next couple weeks, I should have the product and have it installed. The shop has a dyno so I am considering running the car with and without the cat to see the hp difference.
Thanks all for the info!
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#19
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The testpipe on Fabspeeds' website does look like my SFR pipe.
However, the cat-back on their website looks nothing like my SFR setup.
Whoever made mine I care not, I love it.
However, the cat-back on their website looks nothing like my SFR setup.
Whoever made mine I care not, I love it.