Kerrdogg

After I was pretty much convinced the starting line was bald I decided to weigh the GS (2011 M/T) last night at PBIR, 3360lbs , the guy at the ticket booth zeroed out the scale before I pushed the car on even asked "Aren't these made of fiberglass so they are light?" I laughed and said not this one. The weight includes my stereo add on (40lbs) and sound deadener (50 or so lbs) hope to be adding headers so that might knock 20 lbs off or so, here's the kicker with me in it with safety gear 3620 lbs @ 1/4 tank of fuel.

On a side note after Joe G set a new record time for clutch spring removal (Thanks Joe!) I cut a PB 1.97 60 ft and ran a 12.35 @ 114.07, the sad thing is before the cam I ran 12.61 @ 113.9 with a 2.05 60 foot so that being said I have shown no gain from the cam and intake swap yet, all I can say is I must be the first jackass to install a cam before exhaust on a Corvette..... Headers should be here any day, they better work or this bitch is going down the road...

JUIC3D

You have a road course car, not a 1/4 mile car. No 2 ways about it.

Did you do any weight reduction for the quarter mile? Pull the passenger seat? Front sway bar? Slicks/skinnies?
Those huge front wheels/tires, bigger brakes, dry sump system, etc, all add substantial weight.

GMHTP just dynoed a 2012 dry sump LS3 and they said they got 415whp out of it. . . I'm not sure how accurate that is but damn, that's a good dyno sheet for a stock motor.

I personally think it's just a gimmick to promote the 'hand built' LS3 but. . .

My race weight is 3028lbs.

Do you have any more information on your launch/shifting technique. The weather was supposedly good for that event so I'm surprised to see you only have a 114mph trap. For comparison, my car went 11.6@117 with intake, headers, and no tune.

Kerrdogg

Yeah she's a brick, almost kick myself for not going with the base car and some fat CCW's and the blower like I originally had planned. Oh well, I didn't even know the GS was dry sumped till I had driven it home, then I was like crap, 10 quarts of Mobil one (sometimes my cheap side still shows )

I would think the dry sump would act like an under drive pulley, we hardly ever saw gains on a dyno but the numbers would be apparent at the track. The 12.35 @ 114 pass was in my opinion about as good as it could get, a 1.97 60 foot on the stock tires, flat shifting at 6500 rpm every gear. (It might have like some more revs but the rev limiter was still there). I'm sure drag radial would help brake into the 11's but that is not what this car is about, this is my classy / fun / date car / driver. I have a drag car, it has slicks, a turbo and weighs 2,600 lbs, if I can ever get the tranny back from our neighbor it will be at PBIR popping wheelies and such . Back to the vette, my only thought is that the extra flow from the cam is hurting the exhaust so much that Dan had to pull the timing back so far that the gain from the cam is almost invisible. (It's at 16 degrees midrange and 22 up top). The headers will be here any day, my buddy is going to coat them for me and then we'll stick them on with the zo6 exhaust and re tune it, at this point I am expecting a very large gain from the exhaust package and tune. Hope to have it done and on the dyno / track next weekend.

Joe_G

Kerrdogg, it was a pleasure to finally meet you and I'm glad to add you to the list of my successful "Spring-ectomies".

Here's your vid. Next time get some drag radials, that's what you need more than headers! The low trap is due to the fact you have to baby it so much off the line. Plus your clutch will appreciate it, you were really slipping that bad boy to get moving.

Kerrdogg

Thanks for the video Joe. No doubt the drag radial would help but they won't raise the trap speed 8 or 9 mph where it should be. As far as babying it off the line that was about 4800 rpm with the clutch dragging out, the tires threw in the towel and chirped, I got more aggressive the next pass and cut a 2.06 letting out of the gas to get it to recover. Like I said earlier for drag racing I picked the wrong car, the 1st gear is all wrong and the weight is porky but whatever I just wanted to see if there was improvement, I didn't feel any driving down the street so hopefully the headers will help and Dan will be able to lean on the tune a bit without detonation like last time.

I don't know if I ever mentioned my other LS project to you guys, it's got a 5.3 large frame 72 mm turbo, 4l80, circle D convertor and full aluminum exhaust, it should drive to the track with AC on and run 9's, oh and it's ugly, 1980 Zephyer box ugly.

Here's a short vid of the turbo Stang running, the grinding noise is the tranny and the reason why it's out and at the neighbor's shop, I don't know nuttin about Liberty four speeds except this one sound bad and needed an input shaft .

http://www.youtube.com/watch?v=ZG6-7...feature=relmfu

JUIC3D

Holy cow that thing is quiet John. You need that exhaust asap.

Kerrdogg

Waiting on the big brown truck for some O B ... shut your mouth headers!

When you did your install did you need o2 extensions or can you just solder extra wire length in? I have seen 24" and 36" extensions, but if you aren't running meows then can't you turn off the second set of sensors and just plug the holes?

JUIC3D

I wouldn't solder wiring for something as critical as the 02 sensors wiring. Casper electronics sells some really nice OEM quality extensions and that's what I used in my car.

Rear 02s are unnecessary as they only serve to measure catalytic efficiency. Since you either have high flow cats or no cats at all, those sensors will be disabled in the tune so you don't have a constant CEL. I used my 02 sensors to plug the holes until I bought a wideband at which point I replaced 1 with the new WB02 and used the supplied plug to plug the other hole. I still have the rear 02 extensions in the car since it was a bitch to get them out with the headers installed.

When I do the clutch swap next week, I'll be pulling them out.

Kerrdogg

Yeah I know John (Caspers from my Buick days, he used to have an AC Cobra kit car with a GN drivetrain swap) he makes nice stuff like you said. Do you need 36's or 24's for the front extensions?

A buddy of mine just stopped by that has a 9 second TT Saleen street driver, watched my video and laughed at me, watched your video and said "Hold Shitzt" that thing gets moving.

Did you see my PM on the ZO6 exhaust?

JUIC3D

Damn, 9 second street cars are nasty. I can't wait to have one of my own

I did see the PM and posted in that thread. I'm doing the clutch/rear end now and that doesn't leave much leftover $$ to play with. I'll do the exhaust at some point, I just don't know when.

I got the 36" versions I think. I figured I'd rather have too much length, than not enough as I could just ziptie up any excess.

MikeSVT04

So 3300 lbs without ur add ons. I'm okay with that. I was expecting like 3500 haha.

Joe_G

Here is my ragtop with skinnies and seat out as you saw it Saturday.

Its a wide body too, but my brakes are lighter and no dry sump.

The skinnies and seat out save about 85 lbs. Light c5z wheels and drag radials save about another 30 over your run flats if my memory serves.

JUIC3D

Can you get it any lighter than that Joe? How much fuel did you have in that pic?

You saw mine...3028lbs with the same configuration. I can't imagine the convertible adding an extra 137lbs... or can it? The widebody couldn't add all that much, could it? 10lbs at most?

Joe_G

The wide body didn't add anything, and I can tell you, the fenders on our cars are LIGHT. I can't believe GM went through the trouble of making front fenders carbon fiber, I think stock weighs like 2 lbs.

I was low on fuel, probably 1/4 or slightly above. At those times, we had to go 10 miles from the track for fuel so we didn't run as low as we can now. I didn't remove washer fluid and I run full on that most of the time.

I think the rag top adds something but not too much, I thought 50 lbs but don't recall exactly. Don't forget my car is fully loaded with NAV, heated & air bagged seats, HUD, etc., normal sized battery, etc. etc.

Last time I weighed it was more as I keep lug wrench, compressor, plug kit, etc. in the cubbies. When I made my record run I think it weighed over 3250 since I was 1/2 to 3/4 of fuel.

JUIC3D

Mine is a 3Lt as well. The nav was replaced with a 6 disc changer and I doubt there is much weight difference in the 2. I removed the antenna for the NAV but it was a few ounces at best.

My driver's seat is heated with side air bags etc, as well. That's why I'm not sure, aside from the convertible, why yours weighs so much more than mine. Same trim level, same amenities(HUD, heated seats, etc) but 130lb weight difference.

We both have C5 brakes so the only other difference I can see is the lighter battery, but that was only 20lbs.

Kerrdogg

Headers showed up today, will take the time to wrap them up and they should be installed Monday or Tuesday, hopefully a tune mid week and some found power!

Bedouin

My '12 GS, LT1, NPP, 6spd manual coupe has a shipping manifest I got from the dealer which says it weighed 3260. I've yet to weigh it myself however.

JCtx

My 4LT CE MZ6, also with NPP (basically every option available), said 3,306. So at least we can deduct the difference in weight due to options is 46 lbs. Having said that, we have to at least add fuel weight to that, to a more realistic 3,400 lbs fully fueled, in my case. I'm curious if automatics still weigh more than ours, even with dry sump and differential cooler. My guess is drivetrain weight difference should be almost identical, but curious to find out .

FloydSummerOf68

I definitely thought it would be heavier with the 19x12s and 325 runflats out back.

3 Z06ZR1

Hi, I'd do a search on the clutch spring removal.
Read on it's function! I'd pop it back in! The feel of the clutch when I had the spring out was poor. Plus it didn't return completely to the top. Can't see where anyone thinks it an improvement with no spring! Plus thats a pretty slow GS for stock let alone with
mods! Good luck on improvements! The driver mod is key!