No More Clunk In The Rear & 10 More HP

[rsiwicki]

I finally got around to re-installing new bushings (bought new poly's 300ZX) for the differential. Somehow the ones installed several months ago were never installed correctly still creating a very nasty clunk sound from the rear of the car leading me to think my original differential was shot and so when I replaced it with a much tighter 4.08 rearend I was still surpised to hear a clunk/thud from the rear of my car which required a different mechanic to reinstall the new bushings correctly. The car has no more clunk and is very solid sounding.

I also got another 10 HP this weekend thanks to the cooler weather. We have highs only in the high 80's now versus low 90's and the air is less humid making for a scientific butt dyno estimate of about 10rwhp more.

Unfortunately, I am still getting an error on the rear TCS/ABS sensors even after installing a new used sensor so now I am thinking f_ck it. I will try to find a whole uncut sensor wiring harness and also try replacing the relays under the battery just for good measure and see where this gets me, but I never use TCS anyway so it is not that much of a biggy.

Now for the excitement…now that I don't have to worry about the clunk/thud from the rear it is off to the drag strip to see what the old beast can do these days as I have not been up there in a long while. I will try to get up there in the next 2~3 weeks for some fun.

[Q_SHIP]

I might run the bone stock Y33 at the track this weekend. Im going down there to watch some buddies run and I might just to see what she does.

Im guessing around a 16.

[3rd Q]

Rob,Glad you found some TCS sensors (Greg's ?) for the diff, too bad it didn't cure the problem. Are you planning on keeping the Q then? Can't wait to see some time slips on the '69!Paul

[rsiwicki]

The track generally will not allow me to run the vette without an approved NHRA roll bar. I had 3 different answers, one person tell me no problem as long as it does not do the 1/4 less than 14 secs, next person tells me it had to has to havea a roll bar regardless of ET's, and lastly I got an answer saying that it does not have to be NHRA approved roll bar and can be any old in aftermarket (for looks only) roll bar which would not require any cutting. These responses all from the same track and 3 different people. Go figure….guess it will be luck of the draw on who is working there that night and how tight they are on restrictions.

To put a NHRA approved roll bar into the vette is near impossible without major modifications to the rear deck lid that covers the covertible top. I am not going to do any cutting of the rear deck lid so I can run the 1/4 a few times. I will probably take the car to get weighed and then buy a G-tech that should get me within 0.25 secs which is nothing like lining up side by side at the lights on the track, but will get the job done none-the-less.

The last owner took it to a Corvette Club 1/4 track day and did 13.7xx about a year ago and the car is exactly the same setup. I can chirp 1st, 2nd, 3rd very nicely, but have lots to learn on how to properly drive a manual having never owned a manual before. My launch techniques need a lot of practice along with trying to do something called a power shift by keeping rpms up while shifting. My guess is that I will be in mid 14's until I learn the car better. I so far have 400 miles in 2 weeks of ownership on the vette….that is a lot good times and I did not drive it for 4 days last week due to the rainy days.

The new TCS/ABS sensors from Greg are a tad different in design than my originals but seemed like they should work, however, I still get an error just like I did before. We sodiered (sp?) the connections but still getting same error so now maybe somehow it is a relay that is malfunctioning. It is very nice to have 2 cars again so while one is in the shop getting fixed I still have a set of wheels to drive so I am seriously rethinking about keeping the Q versus getting a truck but only time will tell if/when I buy a truck. Something about owning the vette makes me want to buy a SUV or truck versus driving the Q.

I might put back on the 15" BBS just for kicks to see what the lighter wheels will do for me in the 1/4 mile.

[Q_SHIP]

Thats backwards. Here you only have to have a cage in a sub 11's car. 13's you have to wear a helmet, 14's nothing at all.

Really, who wants to put a cage in a car in the 13 second range?

[rsiwicki]

It being a convertible is making things difficult. If it was a coupe I would have no problems until I got into the 11's and as you say would need a cage.

[elwesso]

Thats backwards. Here you only have to have a cage in a sub 11's car. 13's you have to wear a helmet, 14's nothing at all.

Really, who wants to put a cage in a car in the 13 second range?

Plus, thats simply NOT something you do to a numbers matching car...

Rob, since you got the vette, why do you not like the Q as much???

[AZhitman]

Rob - Are the bushings you refer to the two donuts on the front sides of the diff?

I think I need those too....

I've got the same issue with my 240 - It should theoretically (on paper) be a low-13's car when finished, but I'll not be dragging it - they require top up and a roll bar for 'verts.

Not gonna happen.

BTW, the newer G-Tech is more accurate than that (within 1/10th of a sec. in the quarter).

[rsiwicki]

Wes....Don't get me wrong, I still like the Q a lot (main reason I have not put it up for sale), but I have always thought that the perfect combo would be to have a SUV/Crew Cab Truck & a hot sports car. The vette is a lot faster than the Q from 0-70….at 80mph as the 4.11 rearend in the vette and a 4-speed puts my tach at 4,000rpms and with a 6,000rpm redline it starts to lose its power quickly. This problem will be fixed in November with the installation of a new 6-speed transmission that is a direct R&R kit (new driveshaft, mounts, etc.). I have finally tracked down the last known owner of the vette back in 1993 and he told me that engine was fully redone by previous owner for which he had the build sheet (trying to find it again for me) and is a full roller engine with forged internals with about 16,000 miles on it given the current odometer reading.

Hmmm…maybe the perfect combo would be 3 vehicles…..vette, truck/suv, and a heavily modified SC Q45?

Greg...this is the link to the bushings I bought. It is literally night and day difference with the new bushings. The problem was with the bushings around the 2 rear differential studs. They were never properly installed several months ago so I ordered new ones.

Thanks for the info on the g-tech....that is very good news.

http://www.courtesyparts.com/M..._Code=
Modified by rsiwicki at 4:43 PM 10/18/2005

[5seryan]

Rob if your board with your Q, Ill trade you mine. then youll have plenty of fun and games. But seriously I want your car but cant dump mine.

[jamesmost]

beltronics makes a g tech type of product as wellhttp://www.beltronics.com100 milliseconds accuracy out of the box 50 ms accuracy w/fine tuning$99-179 on their site$89-149 elswhere

[Jeff Williams]

beltronics makes a g tech type of product as wellhttp://www.beltronics.com100 milliseconds accuracy out of the box 50 ms accuracy w/fine tuning$99-179 on their site$89-149 elswhere

I have the same issues with my 2000 Corvette convertible. I want to take it to Road Atlanta, but need a roll bar. I think I have the answer, though...A hard top convertible. The only problem is that it is about $4K for the Z06 hard top kit.

I like the idea of the G-tech comp.

[rsiwicki]

yeah.....I have the hard top sitting in my closet that came with the car, but I don't know if they would approve of it and it weights a good 100+ lbs not to mention it squeaks when installed making the 80 minute drive to the track very tiresome. I think I will stick with the G-tech or Beltronics thingy.