My car seems to go to just a little past 5K and stop? is this normal? do the 85 firebirds come with rev limiters? my engine is in my sig. Thanks Guys

 

LG4 is air limited. no rev limiter.

 

so why does my engine seem to stop at about 5100? Its weird cause it seems like im making power all the way up then it like stops. Is there something wrong with my engine? if its the ignition i have a hypertech coil and cap kit coming by friday. will that help???

 

Valve float maybe? I've had mine up to about 6,500 rpm but usually shift around 5,500 to 5,700.. I do have some stiffer than stock valve springs in though.

 

As far as stock HEI they're only goof to 4500 and then they fall off. Right now I'm doing new 355 and I also bought the Hypertech kit, they kicker is that they don't send you a coil module so figure another $40.00 shot in the butt for that otherwise your new Hypertech is not working to potential cause it's missing a peice of the puzzle. Then I took it to a guy in town that cuts off the vaccum advance, installs new bushings (my weights were jumping over each other-way worn out), puts it on his machine and sets the springs so it'll be at full advance at 3000rpm. He said after these mods and his magic that the ingition will be good to 9000rpm (all the stock car boys run these) and that it's everybit as good as an MSD as far as spark energy. The only draw back is that with an MSD you can hook up all kinds of nifty rev-limiters, 2 & 3 step boxes, etc...but I'll buy that later after car gets more important stuff done. My original motor was the same way in that it stopped at 5000rpm-I had to let a vette go because of this-man that sucked!

 

Something else to look for is.Some of the F Bodies came with whats called a resistance wire.It's the wire that supplies the voltage to the Distributer.Check it with a volt meter,If it does have a resistance wire it will only be getting 11.5 volts.It was GM's way of taming them down some,so they wouldn't give too much competition to the higher option camaros/firebirds.

 

By chance is that resistance wire the wire wire (on mine anyway) that plugs into the distributor by the battery plug in?

 

The Resistance wire will be the main 12 volt source for the distributer.It's usually pink I believe.It's marked + on the cap.

 

i have the msd box hooked up..doesnt that change the voltage thats going into the coil? Its a 6a no limiter. like i said, the hypertech kit should be in tomorrow, and im going to get an hei module to go with it by next week. What do you think i should shift at, with all that stuff done? what will be my rpm limit, cause i dont want to blow this engine.

 

just so no one thinks i made a mistake, i do have the in cap coil.

 

As far as shift points go, that's going to be trial and error. With a stock 305 I would keep the revs below 5500 for sure if you want to have longjevity.(show me a dyno where anything but a race motor made more power above 6000 rpm) I've seen some guys pick up .2 by changeing to a lower shfit point 6000 rpm to 5000rpm just because that's where the motors power was and utilized it better.

 

My motor pulls up to 6k but my junk heads choke it...With a good set of vortecs this summer i should be able to shift her around 6,500....