First real HP mods: Thunder Racing Performance Pack
We took it out for a ride and it felt strong. GMHTP stated that they gained 30 rwhp with the kit on their 1994 Formula project. Once I finish up round one of my mods then I'll get it back on the dyno and the track. My stock numbers are in my sig, and I'm hoping for a 20 rwhp gain from round one and consistent 13's.
We also got a couple quick clips, before and after. The videos don't really do it justice, but they show the difference. My brother will post them up later.
After that we took the LT1 and the G8 out for a little fun and to see how they stack up now. When the LT1 was stock the G8 would pull it a solid 1.5-2 cars to the top of second gear. Once the LT1 hit 3rd gear then the G8 would run away HARD. We ran a few times last night. From a 1st gear roll the LT1 actually pulled out almost a car on the one run that it caught traction. After that the G8 stared pulling back, but not too fast.
From second gear rolls they were very close off the hit, with the G8 pulling maybe a 1/2 car to about 80mph and then maybe another car from 80-110mph.
We tried it from a dig twice. The first time the LT1 blew the tires off so bad that it wasn't even a race. The second run the G8 pulled out about a 1/2 car (had to ease into the gas on the LT1) and then slowly walked away about 1-1.5 cars up to 100 mph.
In the next day or so I'm gonna throw an old set of Nitto drag radials on the LT1 and then we'll run them again. We'll try to get it on video next time. Based on what I saw last night, the LT1 should pull out decently down low and then the G8 will be playing catch up.
And I how heartedly beleive the G8 will be playing catch up, a stall converter and a DR will clearly show that.
Last edited by BlackScreaminMachine; Feb 9, 2009 at 09:02 AM.
Magnaflow catback and K&N CAI - http://s166.photobucket.com/albums/u...t=MVI_0480.flv
The sound is 100% different and, in my opinion, about 1,000 times better with the Magnaflow. It's a bit louder at idle and a lot louder when you get on it. It was much raspier and tinny before, but now it's real deep and mean. And for the three hours of work we put in to do the entire performance pack, you can't really beat it.
The Z28 definitely picked up a LOT from the last time we ran them (when the Z28 was stock); I was shocked at how it actually pulled a bit down low on the first gear run that it hooked. I knew it was gonna do better, but I was surprised at just how much better. And even on the first gear run when it was spinning a bit, it still stayed right next to the G8 until partway through second where it lost half a car, then third the G8 pulled a bit harder. There's no doubt in my mind the LT1 is a high 13-second car.
Pic of the car:
Trending Topics
Given the current mods and even with a cam, as long as there is a decent 3kish stall that car will being beating up alot of stuff on the street.
The Best V8 Stories One Small Block at Time
On the EWP, when the wiring is done, make sure you wire up that light to tell you if it is not work.
Also wire it so it's not Key on Engine off, that was my biggest drain on power and my battery never held a good charge, thats w/ a new battery, and Alt, and a mini starter, the comp ratio also was a major factor, a small one to clear the LT's
For RR's there is no power diff between Alum vs Comp Cam Pro mags, but when the cam goes in going with the Pro mags is cheaper and stonger in the long run.
Those are definitely good ideas for the water pump. No need to take any more risks than needed.
For rockers, I'm strongly leaning towards the Hotcam kit (great driveabilty, should be decent on emissions, and compatible with N2O or blower if I ever decide to go either of those routes), so I might get that and just throw the rockers/springs on first.
http://s166.photobucket.com/albums/u...t=MVI_0480.flv
Those links should work (thanks for messing it up, Joe
)z_speedfreak, the G8's are rated 361 hp and generally make around 300 to the rear wheels. Mine weighed in at 3995 without me in it and ran 13.52 @ 102.9. It really seems to stay strong after 100 mph though, where the LT1 kind of falls on it's face in 3rd gear (in comparison). An LS2 GTO will walk away from a bone stock G8. My G8 is dead even from a roll against my father's stock LS1 GTO.
Quality 1.6:1 rockers are a great upgrade, mostly for valvetrain efficiency.
The increase in lift itself isn't worth much. I wouldn't waste my time (or money) on 1.7s.
It's not a P/V issue, it's just increasing stress on the valvetrain with the increased ratio for little/no gains.
High-flow cats (if you keep stock Y pipe), longtube headers (if you don't have to pass visual),
a mailorder tune, electric waterpump ... all good next mod ideas

Cams (or Heads/cam kits) are a little bigger undertaking.
Hold off on that until you have the supporting bolt-ons in place and have
enough money set aside to deal with "surprises" you run into.
A torque converter will help your track times, moreso once it's more heavily modded.
Not an HP mod, but you'll love the launches .. wheeeeeeeee
I'm not a fan of the Nitto DRs at the track, they just don't seem to hook as well as
the MT or Hoosiers.
Yeah, I have to pass the visual hear, so I'll probably end up going with BBK shorties. I'm considering mid lengths as well, but I've used the BBK's in the past and had great all around results with them.
The car will get a cam down the road, but probably just a hotcam for it's all around performance and compability with power adders (not to mention having a chance with emissions, lol).
For the Nittos, I've been using them for years and love them since I started. On my 2002 Z28 it's to the point that it makes enough power that with the 6-speed I'm ready to upgrade to MT radials or ET streets. For my mild LT1 the Nittos should be more than enough for years.




. lol. Squeeze every last bit of power out of it, plus some Scorpions are only around $220. Great looking car by the way. I love quasar blue Z28's. 