So, in early December I went to Atco and blew the Eaton posi in my Moser 12-bolt. Being a good 3.5 hours from home, Fran from Race Proven Motorsports offered to tow the car to his shop and fix it up for me. Do to the fact that my Eaton broke and was very noisy around turns even when it was working, and the fact that Tru Tracs seem to be dropping like flies, I decided to take the advice of everyone there and go with a spool.

While the car was there I also decided to go for some more power. The previous setup was as follows:
2002 Z28 M6
LS1 lid
FAST 78mm TB
UD pulley
factory LS6 intake
Dynatech LT headers with high flow cats
Borla catback
230/236 .551/.551 112LSA cam
nitrous tune
heavy duty aluminum driveshaft
Moser 12-bolt with 4.10's and Eaton posi
17x9.5 chrome TTM wheels
Monster level 3 clutch

(The car also has a Harris Speed Works wet nitrous kit)

New Mods:
Trickflow 215's (milled to 59cc)
Yella Terra 1.8 rockers
Racetronix fuel pump
42# injectors
spool

They baselined the car after fixing the rear, but before the heads, etc and the car put down 389 rwhp and 353 rwtq. After the new mods it made 438 rwhp and 385 rwtq.


Once they tuned it to be safe on the nitrous it made 430 rwhp and 380 rwtq. The green line is on a 100 shot. In order to get the air/fuel anywhere close on the spray they had to go way big on the fuel jetting. The kit recommends a .028 jet and this graph shows it with the .034 jet. On the 100 shot it actually gained as much as 130-140 rwhp down low, but up top it looks like the air/fuel goes from 12.0 to about 11.2 or so and I gained 85 rwhp up top. I'm wondering if a very slightly leaner fuel jet would pick up any more up top.

The red line is on a 150 shot, but I didn't have a fuel jet size anywhere close and they had to put a .044 jet (kit recommends a .034, but it spiked way righ and they had to abort the run). The next size I had was .044 and you can see the air/fuel drop right out and then peg the meter low. Once I get a few more jets to play with and talk to the guys at HSW, I'll get it back on the dyno and see what kind of numbers it can really make on the 150.


The car runs great and feels strong as hell the few times I beat on it. I haven't sprayed it yet since the new mods, but that's on the way

My goals for the year are to really get my driving down and put up some decent numbers at the track.

Big thanks to Fran, and all the guys at RPM! The car came out great, pulls strong as hell, and they even picked me up at the train station when I got in to pick up the car. The shop is extremely clean and well organized and all of the cars being worked on there are being handled with care.

 

Nice. I had similar issues with hsw jetting too. Get it squared away and that should be pretty quick. What kind of mph you think its going to pull o the 150 shot?

 

That's a good question, based on how I've run previously at Lebanon (I've run at other tracks and gone faster, but usually Lebanon so I'll stick with those numbers). The car usually trapped 117 on motor, but once I put the 28" tires on it I couldn't seem to get better than 115 (although it was 85 degrees that day). On the 100 shot that same day I went 124 mph, so I gained 9 mph. I would like to see 120 mph on the 26" tires and 118 on the 28" tires now. I'd like to see 127 on a 100 shot and maybe 130 on the 150 shot once it's working right.

That sound reasonable?

 

I could see it going 130 if you hit all the shifts good. Im hoping for something similar with ms3/150 shot.

 

congrats again ron youll def see 130 traps

-brandon

 

very nice comparision for the heads...good back to back dyno results...a gain of 49rwhp is very nice...what thickness head gasket are you using...also did you have to flycut the pistons...

 

Thanks!

No fly cutting. GM MLS head gaskets, but I'm not sure on the thickness for those.

I've been thinking about going bigger on the cam now that I have the heads to flow.

 

i will let you know how my LSL 239/243 .624/.624 on 111+4 does here in the next month or so i am flycutting later today...also remember with the 1.8s you are actually running a bigger cam...

I am going to be using .040 and probably around 58cc...might even go 57cc and put me around 12.1:1 and run a dual tune pcm for 93 street and 100 track...hmm decisions...

 

^Definitely curious to see how it does.

Yeah, I think my cam went from around .551 with the 1.7's to .583 with the 1.8's. I figure if I get a cam with around .570 with 1.7's then I'll be right around .603 with my 1.8's.

I will say that I'm suprised that the torque was kind of low with this setup. I know alot of cam only cars make right around 380 and heads/cam cars are usually in the 400 range.

 

chris dont be a bitch do 57cc thats what i did.... im hoping for 12.0 :1 ish

 

Nice gains!

I do think the torque is pretty low. I made that torque cam only. You should be right at 400tq. I'm sure it'll run a good number though

 

My brother (PewterscreaminMach) and I went out for a little real world testing. His car is a mild head/cam M6 2002 Z28 that made 400 rwhp and 367 rwtq on the same dyno that my cam only setup made 400 rwhp and 363 rwtq (not the same dyno that I had it on this time). Previously we had done a few runs from 60 mph in 4th gear to the top of 4th to see how the cars compared. This meathod takes driving out of the picture and keeps the gearing the same. Before I got the heads he would pull very slightly, usually getting about a 1/2 car on me and occasionally 1 car.

Tonight we went out and did the same thing a couple times. Every time the cars were dead even for the entire run. Obviously that means my car picked up some, but I didn't pull away at all, not even on the top end. I honestly expected that with a 40 hp gain it might be close at the start with my car pulling (at least slightly) up top.

Thoughts?

 

are you flycutting or do u have pistons...also you going to run a .040...

haha don't tempt me I will go 56cc

 

Your brother installed a 50 shot on his car and is not telling you! Seems like decent gains, I'd try to get your lift up around .610-.630" where you can take full advantage of those heads. That doesn't really seem to make sense at all.

 

do it! lol

 

After we ran my first thought was that he was going to get out and start laughing because he had done something else and not told me. Not the case though, unfortunately.

I think a FAST will probably come before the cam, but I would say that the car will be getting a bigger cam at some point.

 

Who spec'd that cam for you? It looks mighty familiar. Only difference mine is on a 113+3 and unless I'm wrong I thought the lift was .623 Almost twins, well at least cousins.

 

it's all in the family...it is really close to a ms4 and g5x4 also...Patrick G speced it...hopefully I show some good results like you did...

 

I'm honestly thinking something is not right with this setup. Gaining 1/2 to MAYBE 1 car length from 60-110 after installing TFS 215s and rockers just doesn't make any sense to me. If it really picked up 40rwhp from where it was before, then I can't see the car gaining any less than a couple car lengths from where it was before on a run like that. If nothing else, it should have been pulling pretty good up top considering you supposedly have 30rwhp more than me (both SAE on dynojets).

But the next to nothing gain is what surprises me the most. I just don't understand how installing TFS 215s with rockers (coming from stock 241 heads and rockers) could net only a 1/2 to 1 car gain over where it was before.

And this is coming from a car that's notorious for making great power and backing up the numbers at the track (ScreaminRedZ's). Something seems wrong to me.

 

Larger cam dude