A couple years ago my brother bought my 1994 Z28 from me. The car is an automatic and originally came with 2.73 rear gears. Bone stock it made 230 rwhp and 273 rwtq SAE on a Dynojet.

By the time I sold it to him I had installed a K&N cold air, 1LE intake elbow, throttle body airfoil, and a Magnaflow catback. I also swapped the 2.73's rear for a 3.42 rear from a 6-speed LS1 fbody, along with an aluminum driveshaft.

Once my brother got his hands on it he threw an underdrive crank pulley and electric waterpump on it.

Before moving on with his mods he wanted to get it back on the dyno, but it didn't go as planned, with the car putting down 250 rwhp and 273 rwtq, with a terrible curve as it broke up. From inside the car you couldn't tell it was happening, but if you drove next to him and he gave it some gas then you'd hear it popping.

With about 80,000 miles on the car we swapped out the plugs and wires, and it seemed to fix the issue.

Last week we threw it back on the dyno and here are the results:

Green curve is last time, blue is after the new plugs and wires.



Not earth shattering numbers, but at least he's running at full power again!

Next up he's got a set of 1.6 roller rockers w/valve springs ready to go in, and he's hoping to get a set of headers on it.

P.S.

My brother also bought a used Hypertech Power Programmer 3 for $40, that he used to correct the speedometer for the gears. Since we had it anyway, I decided to see what would happen on the dyno. The graph posted was with the factory tune. On the immediate backup pull the power dropped to 268 rwhp.

After that, I installed the Hypertech tune, which took long enough that it allowed the car to cool a bit. With the Hypertech engine tune it made 267 rwhp. Also, the air/fuel was the same as the stock tune until about 5000 rpm, where it stayed lean when the factory tune dropped a bit.

I know most people won't be suprised by these results, but I thought I'd post up what we found.

 

with roller rockers and longtubes possible 300rwhp

 

For an auto car, with its mods, and it being a 94, atleast you can say its still making good power!

So in the end the hypertech hurt just a tad? its probably cheaper then a dyno tune for only a 5hp diff though, so thats not the worst.

 

I agree, but due to emissions and cost, he's probably going to go with Mac headers with a high-flow cat. I still think 290 rwhp is possible though.

I thought the power was pretty decent. A 6-speed 1997 Z28 with a cold air and catback just made about the same power recently on the same dyno, so that's pretty good.

He ran a 13.54 once, but it was like a magic pass that he could never duplicate. Usually he runs high 13.6's and 13.7's. I'm thinking that the car ran clean that one pass. Now it would be nice to see him nail a few 13.5's and maybe even a 13.4.

Looks like the Hypertech tune lost a couple horsepower. For $40 though, it's perfect for calibrating the speedo and you can play with the shift points. Once he finishes out the next round of bolt-ons he'll get it tuned.

 

Good numbers, he'll love the 1.6 rocker mod. Next stop a bigger stall and a 100 shot. Hey, what ever happened to your Camaro. Last I read,a timing chain went south. Did you ever get it back on the road?

 

I think this next round of mods will be just what his car needs. It runs strong through 1st and 2nd, but dies in 3rd. Some top end power should help a bit. A nice stall on top of those will hopefully put the car consistently into the 12's.

Yeah, the timing chain broke and all the valves got bent. I ended up selling the shortblock to someone and my friend and I swapped it in after a performance shop fucked up the guy's motor. My car is still down, but I'm hoping to start working on it soon. For now I'm trying to get the G8 to a point where I'm happy with it for a while. Just ordered headers and an underdrive pulley for it.

 

A stall would REALLY wake that thing up big time. It would feel like a new car. Also put some suspension under it and those time will drop too. I would bet with a stall and hooking up he could easily see 13.00/129X.

 

hey im on shift dude , im sellin my edge converter this winter its a 3.5k stall with about 3k on it . ask anyone on shift about my stuff im legit . also i may be selling my bottom end as well as im going bigger over the winter and its al off of a 94 as well . motor just did 379 r.w.h.p with a cc503 com and such