How much will a cam only change on a Turbo affect tune?
#1
How much will a cam only change on a Turbo affect tune?
Last week I blew the 5.3 in my Chevelle. The tune was fine but I wanted to test the limits of the stock engine and we hit 23lbs of boost before it blew. This week, we through in another 5.3 with more miles on it but left everything stock. So the only change is the cam. The last engine had the XER273 in it...224/230, .581.588 on a 114. Car ran great. Low 6's at 118mph in the 1/8th but at 20-22lbs of boost. This time I wanted to just try the stock cam. Everything else is the same. Same engine, same heads, same valve springs, fuel, injectors, etc..
Here is what it's doing. We just got it running today on the same tune I had. It fired right up and idled very smooth. It did have some blow by, but the engine has 180,000 in miles. I did here and watch the engine run prior to pulling it for my car. Anyways, when I went to drive it, it would backfire and run like **** if you tried to accelerate any at all. I am thinking the stock cam probably is getting way to much fuel but am not sure. As soon as I turn the car off and turn it back on again, it idles fine again.
Driving....it will pull pretty well at part throttle but anything over half throttle and it backfires and just runs like plain ****. Would just a cam only swap cause this or is something wrong with my engine?
Thanks. The cam is just stock. I pulled the engine out of a 2000 running silverado.
Here is what it's doing. We just got it running today on the same tune I had. It fired right up and idled very smooth. It did have some blow by, but the engine has 180,000 in miles. I did here and watch the engine run prior to pulling it for my car. Anyways, when I went to drive it, it would backfire and run like **** if you tried to accelerate any at all. I am thinking the stock cam probably is getting way to much fuel but am not sure. As soon as I turn the car off and turn it back on again, it idles fine again.
Driving....it will pull pretty well at part throttle but anything over half throttle and it backfires and just runs like plain ****. Would just a cam only swap cause this or is something wrong with my engine?
Thanks. The cam is just stock. I pulled the engine out of a 2000 running silverado.
#4
Banned
iTrader: (10)
Ahhh, the guessing game. OK, I'll play! I guess...........crank sensor issues!! LOL
J/K, only way to know anything is to data log it. Dial it in for the new cam, and see what happens.
(Disclaimer: This post is brought to you by boredom! Courtesy of sitting in an airport waiting to board De plane boss! De plane!! LOL)
J/K, only way to know anything is to data log it. Dial it in for the new cam, and see what happens.
(Disclaimer: This post is brought to you by boredom! Courtesy of sitting in an airport waiting to board De plane boss! De plane!! LOL)
#5
I haven't tried to pull the old cam yet. Going to try today but I really wanted to see how it did on the stock cam. JFYI, I wasn't planning on racing it or even keeping this tune but figured the tune would have been close enough to at least have driven around to make sure no leaks, weird noises, etc.. Figured it would fine out of boost.
Thanks, we will look data log and see what it is doing.
Thanks, we will look data log and see what it is doing.