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.

 

Sounds like a nice setup! Think I've seen your car down there parked next to the dyno. +1 for Fran and the RPM crew.

 

Thanks! Hope to have track numbers as soon as the weather gets warmer.

 

+1 for Fran and RPM

How is street driving the spool????

 

Damn, those are some awesome gains, this is looking like a potential ten second car on spray. I'm curious to hear how you like the spool on the street.

Oh, and will you fix your retarded sig already?

 

Fran is great for sure. I also want to know about the spool. On the fence soft locker or spool myself.

 

Thanks guys!

So far I've only driven it with the Nittos. I will say that it's ok once you get going (probably over 5 mph or so), but in a parking lot situation it's terrible. The whole car jumps and shakes and it feels like the world is ending. People look at you like your car is about to explode. That being said, I don't DD the car and feel much more confident now that it won't break, so I don't care about that and am more than willing to put up with it.

Supposedly it won't be so bad once I get some MT's on the car so I'll let you know if I notice a difference.

Also, the car only made 389/353 on Fran's dyno baseline and that's the setup that I had when I broke the Eaton posi. I probably launched it at 4500 rpm and popped the clutch fast. I've also seen people run the same posi in 9 second cars though without a problem, so who knows.

 

I appreciate it guys.

 

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?

 

Just face it, your $2,500 Trickflows can't put my $900 Patriots to shame...

 

hahaahahahahahaha

 

Oooooouch...

 

Good numbers, looking forward to meeting up with some of you CT guys this summer.

 

umm yes that was a BURN

 

I guess the real question is, are the Patriots really better than everyone thought or are the Trickflows just overhyped...

 

Well he made 400rwhp and you made almost 440. Are your guys cams similar? You deff need a fast intake also. I bet you will make almost 460 with a fast.

 

His cam has about the same lift as mine now that I have the rockers, but his duration is less, I believe in the 228 range. I'm just curious why the extra hp that I have over him isn't letting my car pull away? Everything is pretty even between the two cars and we seem to have gone from him being 1/2 a car ahead to the cars being dead even. Is that about right for a 40 hp gain?

 

well your car weighs more, that will make a difference, those TT2 wheels are HEAVY, they look great but are just anchors

 

Similar lift but mine is a 224/228 on a 113 LSA. His is 230/236 on a 112 LSA. I think the only way to compare the power numbers is to dyno them on the same dyno, which would mean him dynoing up here because I'm not driving 4 1/2 hours for a dyno.

Regardless of the numbers they put down, they were as dead even from 60-110 both in fourth gear as two cars can possible be. In those races, it was the same gearing, similar weight, we even both filled our gas tanks at the same time. He's got heavier wheels but I've got an amp in the back, still have my front swaybar, and still have back seats in the car. Everything was comparable enough to show that power-wise either 40rwhp doesn't make almost any difference or the cars are making very similar power and the dynos aren't comparable.

And no, I didn't put a 50 shot on my car just to mess with him. Although, that would have been funny as hell because I would have been pulling pretty hard.

 

As far as actual weight, they aren't heavy enough to make a huge difference (even 5 lbs each would only be 20lbs total). As far as rotating weight, they were on the car when it was dynoed, so they they would have been factored in to the gains. Also, they are the same wheels that were on the car almost every other time we raced, so they shouldn't effect the outcome any more than before.