69 Z/28 Day II Project (Air Force Brat)

[Chuck_Burg]

Originally Posted by NorCam

Chuck, that 2.20 first gear with 3.55 gears and 28" tires will have a final ratio of around 7.80 which is going to pull the engine down when you let go the clutch. Granted your 496 is going to have more torque but there are much better transmission gear ratio combinations for street cars that will also see some highway use. (See the AGE gearing options here)

To keep it fun off the lights with 28" tall tires, I chose to run a 2.99 first gear. With the stock 3:73 rear, this should have a final ratio of 11.15 and will feel like having 5:13 gears off the light. Granted it will be a short shift when driving normally, but at WOT this should keep a good set of sticky tires running on the ragged edge until 2nd gear is pulled at 50 mph. I'd then pull 2nd gear at 4500 rpm and 3rd/4th would keep me in the 5200/5300 range on a full pass.

Best part is I get all the excitement of a great rpm launch that won't pull the motor down and will still have the final gear ratio of 3.73 for the highway runs in 4th. I may even choose to step down to a 3.55 rear gear when I rebuild the diff. That would have me in the 10.6 final range which is even more ideal. With big block torque, you could even go 3.31 and still have a better transmission ratio to easily launch the car without pulling the motor down off the line. Plus it's way more fun launching like it has 4:88's.

Might want to look into the gearing options here and check the multiplier on trans gearing x final ratio.

Good advice! I think I'll go with 3.55s and the current set up initially. If it lugs too hard in first, I'll go with the wide gear set in the AGE M22. I've never owned a car with this kind of torque (other than a magnuson superchargerd 2016 LT1 Camaro, which was just stupid) so I'll see how it goes... I don't think street tires will stand a chance even with the 2.20 first gear and 496 torque.

[NorCam]

Still working away on the car here while the search is on for some good parts. I have a couple sYc members who have a number of good parts including many NOS trim pieces that are aligning well for use on this car. Should be hitting the body shop with it in just a couple of weeks.

In the interim, I'm hoping that an sYc member may have a swath or two of original 714 Yellow Houndstooth fabric available so I can repair the covers on the front buckets. I know the dye lots differ but would love to know if anyone has a couple chunks squirreled away that they would compare/share so I can maybe get one or two seats up and running with some original cloth?

Here's a sample from Al Knoch (very bright vinyl) while I await samples from SMS and others. Looking for a more buttery vinyl.

[NorCam]

Had to get a bit creative while getting the diff out from under the car as it was sitting on the 4 post lift but it's out now and will soon be stripped down and rebuilt. The old ET cover is in great shape with some light oxidization and a few layers of dust. It will be properly restored when the housing is out being powder coated in the coming weeks. Lots to do as the car is out to have a frame jig built under it later this week, then it's off to the body shop for a month or two.

[X66 714]

It looks like it has a 10 bolt....Joe

[markinnaples]

Looks like a 12 bolt to me?

[X66 714]

Originally Posted by markinnaples

Looks like a 12 bolt to me?

I see it now...Joe

[NorCam]

Yup...original 12 bolt rear dated BU 0224. When I first looked at the cover I thought cool, it has the ET style cover but it kinda looks deep from the top down view. Are they all this way with that sort of overall depth? Tearing into to this week with a full restoration planned for it including fresh powder coating. Also adding C-Clip eliminators and performance axle upgrades.

[big gear head]

It always makes me sad to see someone take a nice original rear end like that and add c clip eliminators to it. When you do that the housing is permanently damaged. Do you really need them?

[scuncio]

To pile on, the C-clip eliminator kits tend to leak and do require irreversable changes to the tube interface. IMO if you aren't running slicks and sidestepping the clutch at 5k I would just buy a set of high quality replacement C-clip axles and call it good.

[NorCam]

Originally Posted by scuncio

To pile on, the C-clip eliminator kits tend to leak and do require irreversable changes to the tube interface. IMO if you aren't running slicks and sidestepping the clutch at 5k I would just buy a set of high quality replacement C-clip axles and call it good.

Yes Tony,

Have already looked at C-clip axles and they won't cut it with tech now days. Car should make near to 500 horse and anyone who knows me knows I enjoy side stepping the clutch at 4K. This car will see the track on occasion and in order to meet tech it's going to need c-clip eliminators or a conversion to 9" ends as it will be running slicks. Either that or if I want to step it up, a complete housing upgrade. (I can already hear the cheers)

I have considered a Moser 9" or maybe run a heavier Dana 60 and might go that route if I need a carrier and/or a new gear set. I'll know more on that next week and that may just be the option I choose so go easy here guys. I do not want a broken axle or torn up quarter panel just for the sake of saving an original set of axle tubes in a car that will never see the light of being a numbers car ever again.