87 renix 4.7 vacuum and stalling
Posted: July 21st, 2013, 10:21 pm
Last summer I built my stroker and got it running just enough to baby it home. Now I am trying to actually drive it because I have time to work on it.
1987 renix cherokee and block
96 head
gibson header and exhaust pipe cut just before the cat
scat crank
icon dished pistons
.60 over bore
stage 1 computer friendly lunati cam from rpm machine
stock lifters, springs, rods and valves
Right now when I drive it, it will stall very easily, feels like it has no power, only sounds smooth over 1000 rpm. If i start it, it will die in less than a minute and a half because it has trouble idling. At it bad idle it fluctuates from 8-11 hg. Compression was 120 across, leak down about 20%. This engine probably hasnt ran 3 hours yet and not even a half hour decently.
My biggest concern is this cam shaft, it is not one of anglefire's 4 lunati shafts and I cant find it on their website. The spec sheet that came with it listed: 10689905 grind 34-B185A-B127A Lob
> serperation 114 Lift .432in .426ex Duration at .5 258in 214ex
> and Advertised duration 264in 268ex.
I did not degree the cam shaft because nothing ever told me to do so. My worries here are: is the camshaft in my jeep what is listed here because it seems like a more agressive cam than stage 1. Would degreeing it fix the vacuum issue allowing it to idle again, or do I need to replace the cam shaft.
I ordered a 4529228 mopar performance cam just in case. Is there anything I need to worry about with this cam?
1987 renix cherokee and block
96 head
gibson header and exhaust pipe cut just before the cat
scat crank
icon dished pistons
.60 over bore
stage 1 computer friendly lunati cam from rpm machine
stock lifters, springs, rods and valves
Right now when I drive it, it will stall very easily, feels like it has no power, only sounds smooth over 1000 rpm. If i start it, it will die in less than a minute and a half because it has trouble idling. At it bad idle it fluctuates from 8-11 hg. Compression was 120 across, leak down about 20%. This engine probably hasnt ran 3 hours yet and not even a half hour decently.
My biggest concern is this cam shaft, it is not one of anglefire's 4 lunati shafts and I cant find it on their website. The spec sheet that came with it listed: 10689905 grind 34-B185A-B127A Lob
> serperation 114 Lift .432in .426ex Duration at .5 258in 214ex
> and Advertised duration 264in 268ex.
I did not degree the cam shaft because nothing ever told me to do so. My worries here are: is the camshaft in my jeep what is listed here because it seems like a more agressive cam than stage 1. Would degreeing it fix the vacuum issue allowing it to idle again, or do I need to replace the cam shaft.
I ordered a 4529228 mopar performance cam just in case. Is there anything I need to worry about with this cam?