Just swapped 4.8 to 5.3 and wont start

[slinds]

Just got done swapping 4.8l to 5.3l shaved the heads installed 2000 ls1 corvette cam and ls6 intake and now cant get truck to fire.
I have tested for spark, fuel, injector pulse, and I have an rpm reading from crank sensor, also have taken care of all the vacuum lines for the intake swap. I am running the stock pcm from the 4.8l and i know that will affect how it runs but not cause a no start. Ran out of things to test wondering if anyone has any ideas

[Trevor]

will it crank then die back down? if so then just needs a crank relearn. go to Nelson Performance - Performance without Sacrificing Drivability and look around for the how to.

[RedHeartbeat]

You tested for these things, what were the results? Do you have fuel pressure? Did you remember to connect the cam sensor? Did you pinch any wires between the bell housing and block?

[slinds]

it doesnt start it just cranks so i cant do a crank relearn. I cant test the fuel pressure because the valve goes right into the back of the alternator but the fuel sprays out hard when i press the valve. i have checked all the wiring and i dont have anything pinched in any where. Would i have spark from the plugs if the cam sensor was unplugged?

[ff_jeff]

Maybe this will work.
Nelson Performance - Security Relearn for no start
you have 2 threads on this lol.

[George C]

i truely hate how everyone says you need a crank relearn. i have never needed to do this. ive been messing with this software going on 4 yrs now. never once. ive rewrote pcms from different vehicles and used them in others.

sorry had to rant!!!!!

are you sure you installed cam right?

if it is security it will still start just idle high then die instantly.

see if you have fuel pressure, check make sure coils are plugged in, make sure all your relays are in place.

[ff_jeff]

I thought that sometimes with the security it would just not start.

[George C]

I thought that sometimes with the security it would just not start.

from my experience. it fires then dies

[George C]

also if you happen to bend your valves from having your heads shaved, or cause you shaved your heads and didnt use smaller pushrods now. it wont start either since there isnt a combustion chambe it just goes right out the cylinder

[slinds]

Found out that 4 out of 8 injectors were stuck closed. so $100 bucks later and I have all 8 injectors firing at 100%. The truck is running great just got the program done and everything is great now have the horsepower bug and wish i went with a bigger cam.