Hey guys, me and my friend are working on a 95 z28 bone stock 180k miles! The car is getting paint as we speak and then we are going to pull the motor. He ran 14.0 last year with nothing but mid lenght headers ( I told him to get LTs but he didnt) He wants to get this thing in the mid 12s at lest.

Some questions...
Heads, can we use stock ported, LT4... what are some cheaper options?
Cam... what would be a good streep/strip cam
intake... stock ported, LT4?
Going to run true duals off the mid lenghts, he wants to keep them.

I figure at lest a 3000 stall and the car already has some set of unkown gear in it. Its toped out in 3rd at the strip. Any input would be great. Also we might just buy a freash LT1 instead of a rebuild if anyone has anything. Thanks guys

 

Don't bother with the lt4 stuff. Keep the lt1 stuff and get a heads and cam package from one of the sponsors on here like ai or le. 3000 stall is a good all around size if the car sees street driving pretty often, although you may want to go bigger depending on your cam. Going to need tires and suspension as well.
So boltons, h/c, stall, suspension, and sticky tires should easily be in the twelves.

 

180k miles? Spray it once with about a 250 shot. Run a 11.2 blow the engine in the process, then start building something. >=)

 

Tires are a must, suspension will be stock for now. Are heads a must for mid 12s or can he get away with a little porting on the stockers?

 

You don't need any headwork to get into the mid 12s. A mild cam such as the popular XE503 can get you there easily with bolt-ons and good tuning/suspension.

 

You can mid 12s with just bolt ons. I ran 12.9 on a very soft 1.9 60ft. Get that down to a 1.6 or even a 1.7 and you should see a mid 12...

 

go for a higher stall. Maybe around 3600.

 

Thanks guys, the motor is going to need a rebuild so I was thinking just do new bearings and rings. Throw a cam in it, rebuild the heads with a litttle porting. Not sure how much he wants to spend yet, what about the intake manifold and throttle body.... Any solid gains that can be made there?

 

At this point no. The stock lt1 intake manifold is good to around 400rwhp. If youre gonna port the heads, you can probably go for a cc306 cam if you dont want a custom cam. Itll make a little more power over the 503.

 

With that many miles I'd be willing to bet the block is going to need to be bored, so at that point I'd buy a set of forged pistons and a set of Scat Pro Comp I beam rods with ARP 2000 bolts, turn/polish the crank with new rings and bearings and the cam of your choice. New timing set and all new gaskets and if you have the skill or the money I'd have the heads ported add a stall and at least 3.73's and you'll easily reach/exceed your goals.

 

You will have to pull the pistons out to see if it needs to be bored. Even at 180k with proper oil changes it could be just fine.

 

You'll definitely want these two things due to the difficulty in correcting later or failure at higher power levels.

1. Forged pistons
2. ARP Rod bolts
3. Stock crank (not some POS aftermarket $200 crank)

Everything else can be corrected later (heads work, cam, etc.).

Also, if this is also a driver, don't go to crazy on the camshaft. Head work will actually pay off more than a huge cam on the street.

None of it will work right without a proper tune.

 

Just going to use stock crank, arp rod bolts and have the rods done should work. Were not planning on big power, we just need to be able to drive it to the track, make some runs and go home. He won't be driving the car daily or anything. Forged pistons would be nice, hopefully the crank looks good and this thing don't need to much work. First step is tear it down, if the motor looks shot would it be worth a ls1 swap instead? He said he would be happy with around 400 flywheel for now, he has been out of the game for a long time LOL.

 

Why in the hell would the pistons have to be pulled in order to measure the bore...?

 

You wouldn't have to.... measuring the bore has about jack crap to do with determining whether the cylinders need to be bored....

 

spend a lot now, or a lot more later, labor costs the first, and second time. do it right the first time, its cheaper in the long run

 

Depends what worth means to your buddy. A budget is the first step in this build I think. Figure out the platform first then go for the build. Either way though, the stinky 10bolt isn't going to last too long with sticky tires and getting hit with a high stall.

 

Lol OK... I know exactly what you're getting at and anyone competent could determine bore symmetry, taper, and piston to bore clearance with the slugs in place.

Did you miss the mild part?

Why not just do a damn compression and leak down and go from there?


Too many assumptions that the engine "must" be worn out with that mileage.

FWIW I would consider replacing rod and main bearings if a compression test is within spec. There are engines that go over a million miles and never lose ring seal, but they do like fresh bearings every once in a while.

.02

 

I told him the same, at lest needs bearings and rings with some fresh gaskets if he wants to keep a tight budget. Rebuild the rods with ARPs would be a good idea too just for peace of mind. I am gonna have to talk to him about the 10 bolt rear too, I know he is gonna want the car to be reliable.

 

Autos are a lot easier on the 10 bolt than the six speeds are, rebuild ut with some 3.73s and get a good install kit and it will be fine.