Boost to High?

Adam155724

Registered User
Well I have a feeling this is just a faulty stock boost gauge but I would like more opinions.
When I first got the car and went WOT the stock boost gauge would measure to about 12 lbs @2500 rpms the by the time it reached 5000 it would read 15 lbs. Then I installed a 5% OD pulley and now it reads 15 lbs @2500 and since that is where it pegs the gauge, all other readings are NA.
Since I have deleted the mufflers(sounds horrible, getting fixed soon) The gauge reads 15lbs a little later around 2800. I know the stock gauge reads backpreasure and isnt very accurate but the way its acting is goofy. Any Ideas?

Other mods incluse:
MP raised top
9in conical filter
Owner before said he gutted the cats
 
If your exhaust is stock then thats where the problem lies.
Backpressure from the restrictive stock exhaust can cause excessive boost pressure.
Before increasing the intake components the exhaust must be improved.
If not the head gaskets will not last very long.
Gutting the cats will help only a little.
The stock exhaust merges into a VERY small resonator. I believe it's dual 1-7/8 into about a single 2" pipe or resonator.
With the mods you have I would STRONGLY recommend updating the exhaust.
Deleting the mufflers will only relieve a small amount of backpressure.
Which is why you are probably getting 15lbs at 2800 instead of 2500 previously.
In regards to the gauge the readings, they are consistent with an increase of boost into a stock restrictive exhaust.
Check out this article.
http://www.sccoa.com/articles/cwexhaust.php
 
Same as above, you need to take that pulley off and put the stock one back on untill you replace the resonator. That is the major restriction in the exhaust. That little $50 part could quite possibly cause you $1000+ in damages soon. Flowmaster has a kit if you are up to doing it yourself.
Also, 15lbs is a little on the high side for a stock SC. You could also have pieces of the old catylitic converters clogging your exhaust.
 
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