after a little over 4 months of working on and rebuilding my Z, i will finally be turning it tomorrow. the engine was rebuilt, trans rebuilt and will have new exhaust. right now, it only has the headers and tubes. rest of the exhaust is in a box, pending the outcome of the turn(s). today i was finally able to put power back on to it, so i rolled the engine over with the starter with no spark or fuel to check the valves and rods. they seem to be good, didn't see any binding or anything, so i buttoned up the valve covers and moved on to putting everything else on. i will be putting a fuel pressure gauge on it and checking IAC and TPS before i light it off, but is there any other things i should check before i turn the key? i will be initially just lighting it off and getting it to run well enough to leak check everything before i actually time it, etc. putting just water in the cooling for now, will dump it later if leaks are good and replace it with coolant. any other comments and/or suggestions are welcome.

my next question would be, if all goes well tomorrow and i get the exhaust put on, what do i need to do for a break-in? this is my first time ever doing a major rebuild so i could use all the guidance you can give me on this. thanks. you guys have been a lot of help and i appreciate every bit of it.

KAM

 

As far as break-in period...I would say at a BARE minimum 500 miles. When I get to mine and do my rebuild...I will probably go between 500 and 1000 miles for the break in.

 

you'll probably want to put your old exhaust manifolds back on the car during the cam break in... otherwise your headers will become dull, and not so shiney, dont know about overall longevity, but I bet it cant help it either.

The cam break-in is about 15-30 minutes of idling time (IIRC). I read that you should vary RPMs between idle - 3k, but I dont think I would... probably better off just letting it idle... but I'm no expert so if anyone else chops in, listen to them!

but after your cam is broken in, then you can put your headers back on, and then just go easy on it the first 1000-3000 miles. 3000 is more than enough, 1000 would be barely enough. (Enough = enough to drive with enthusiasm )....


Enough is one of those words that doesnt look right when you type it even though you know it is.... lol

 

IF you are breaking in a flat tappet cam, you should keep the car at 2000-2500 RPMs for at least 15 minutes. We usually always do 20. No idle time is desireable.

If its not a flat tappet, dont worry about it, rollers dont need broke in.

 

Thank you for clearing that up Ljnowell

 

well here's another question i asked on another forum, but since we're sorta' on the topic...

when i finally got that thing to light off (first run) i noticed very minor seepage around the head bolts in a couple of places on the driver side head, none noticed on the pass side, but after the engine got good and hot, opened t-stat, etc., i never saw it again on any other runs, short as they were. i was told that that was possible til the engine was heated up and then cooled down to seal the gaskets and thread sealer. yes, i put thread sealer with teflon on all the bolts. other than that, almost burnt a couple of wires, ran ok for the most part. tranny lines leak, got a service engine light, probably cuz the IAT wasn't hooked up, but haven't checked the code yet. for the most part, doesn't look like the eng and/or trans would need to come back out so will press on with putting the full exhaust on, which i'm sure will help with trying to time and tune this thing... that is, when i can get back to it...

KAM