Wickedone

iTrader: (12)

Motor is stock and swapped into my RX-7. I installed a LS2 timing chain, Melings oil pump and underdrive pulley.

Now the motor looses all power at 5500 rpm's. It is kinda acting like it is hitting rev limiter. Other than that is seems to run fine, idles smooth, revs smooth and has power. I was very careful to make sure nothing moved when I installed the new chain but could it be a tooth off? What would it run like?

Any other ideas what could be wrong?

CamaroZstyle28

iTrader: (1)

Sounds completely fuel related. What fuel pump are you using ?? If the motor is stock then the stock size injectors and rails are plenty just take them apart and clean them (injectors) or buy new ones. Do you ever get a long cranking time?


>>Check fuel pump/clean injectors>>




good luck

Wickedone

iTrader: (12)

Forgot to mention I thought is was a fuel pressure issue that turned out to be a bad gauge. I replaced fuel pump and FPR. Should be getting a solid 58 PSI.

I did have an issue with a blocked return line and this caused me to have 90 psi, could this have damaged the injectors?

GOaT Cheese

Did your problem only happen after the timing set was installed? If so, I think you know where to look.

slow trap

iTrader: (22)

^ what he said. if that isn't it you could possibly be experiencing valve float if it isn't fueling issues.

Wickedone

iTrader: (12)

I was extremely careful to make sure the timing chain was lined up but you never know. It there any way to check it without pulling it all apart?

Wickedone

iTrader: (12)

Up Up and away!

098z28

iTrader: (12)

no u half to tear it back apart

GOaT Cheese

You can kinda check it. Use a piston stop and mark an exact TDC mark somewhere on the front cover and balancer. Then pull the left hand valve cover. When your home made timing marks are lined up on the front cover, the #1 intake valve needs to be closed. If the valve is open a bit with the piston at TDC then you definately have a valve timing issue.

Wickedone

iTrader: (12)

What is a piston stop? This sounds a heck of a lot easier than pulling the entire front of the motor apart.

GOaT Cheese

A modified spark plug type tool that has a protrusion, and when inserted into the #1 spark plug hole, you can slowly rotate the engine by hand until the piston contacts the protrusion, this obviously stops crankshaft rotation. when the crank stops, after hitting the protrusion on the tool, you simply mark the balancer and front cover so the marks line up, then reverse the crankshaft rotation until it hits the stop going the other way, then mark the front cover again where your balancer mark is. Now you should have two marks on the front cover and one on the balancer. Now make a third mark on the front cover EXACTLY in the middle of the other two, remove the piston stop, and rotate the crank until the single mark on the balancer lines up with the MIDDLE mark on the front cover. This will be perfect mechanical TDC for #1 piston, and the #1 intake valve should be closed at this point.