hi friends ! i have 1991 camaro RS with 305 tbi and 700r4 trans with 60 k miles on it ! its one the cars that made for export to japan.

i bought 1994 z28 lt1 cam and put it in my L03 , after starting up , the engine was runing rich !!! i used the ALDL and figured out that my map sensor show about 45-50 KPA in idle , which the stock one shows about 25-30 KPA on my car !

what should i do ? how can i change that ?

i did every thing just like this topic :

https://www.thirdgen.org/forums/tbi/...-ultimate.html

all the sensors working great, ive even changed the map but didnt help!

think that it makes engine runing rich (MAP sensor ) . have any idea that can help me ? PLZ

what should i do to change that parameter ?

 

very interesting. My Stock 94 vette LT1 idles at 30-35 KPA. you must NOT have a vacuum leak or you would be LEAN. You installed CAM "ONLY"

 

i checked eveything !

another intresting thing is that when i adjust the TPS , map sensor in going to show 30 KPA , and the car runs fine !

but when i turn it off and immediately turn it on , map shows +45 KPA and the engine starts running rich !!!!!

 

In your case. With the speed density. I would look for a vacuum leak. The cam is not increasing your map KPA.

 

Says who???? I had a LT1 F-car cam in a 305 TPI and it idled about 45 kpa at 650 rpm. Even in a 350 TBI it idled a bit rich. Going from a 179/194 @ .050 cam to a 201/208 @ .050 cam will absolutely throw off the speed density tune. The stock 305 cam makes about 22 in/hg of vacuum @ 700 rpm vs 18 in/hg of the LT1.

My Express van 350 Vortec idles about 45 kpa in gear @ 750 rpm with the a/c on with the tiny 395' marine cam in it. It is only 196/206 @ .050.