ERA - 3 questions for a new owner

[PeternPlymouth]

Hello Everyone,

Three things -

I bought my ERA just last summer and I have 2.80 gears in it.
1. What other ratio gears are there for the Jag rear ends? My number ERA is #287.

2. The small connection bolt for the headers - is this as tight of a fit there is? seems very flimsy, mine cracked ( and the pipe was hanging down and ripped the lower piece of the fiberglass hole ) and i had to have it welded back together. Seems that i am having some exhaust come into the passenger side while driving.

3. I have a light burn / hole on the engine compartment wheel wells because the tires are so big that if you turn too much - it burns a hole in the fiber glass. I would like to patch up the " almost holes " and make it look like new. - thoughts?

Thanks -

PeternPlymouth

[patrickt]

1) There are several available ratios for Dana 44 gear sets. You'll probably want to move up to one of the following: 3.07, 3.23, 3.31, 3.42, 3.54, 3.73, or 3.92. Of course you'll want to pick a rear ratio based on your transmission ratios and the torque/HP curve of your engine. I have a 3.54 with my TKO600 and torquey FE. Post your specs and you'll get some suggestions on what ratio to go with.

2) I'm not sure I understand -- are you talking about this connection from the primaries to the side pipes?



3) Any good Corvette body guy should be able to handle that problem.

[xracerbob]

What size wheels/tires are on the front?

[hoppy]

If you are referring to the strap from the side pipes to the chassis near the door, mine cracked a couple of times. I cut a heavier gauge of stainless, drilled some new holes for the bolts and it's staying in place fine ever since.

[Jim Holden]

The 2.80 ratio works well with a Richmond Gear 4+1 trans in which fifth gears is a 1:1 ratio.

What trans do you have?

What size tires do you have... there are limits.

Jim

[CJ428CJ]

I agree with Jim. The 2.88 rear end along with the Richmond 5 spd is a great combination. If you have the Richmond 5 spd, 2.88 or 3.08 will work about the best. If you're considering changing your existing gears, be careful. Even though 3.21, 3.31, 3.54 etc gears are available they will not necessarily fit in your existing center section. As I recall there are 2 case sizes and the gears between the two case sizes will not interchange. I could be wrong, but I think the 2.88 and 3.08 gears fit one case size and all the others fit a different case size.

Chris

[patrickt]

Originally Posted by CJ428CJ

As I recall there are 2 case sizes and the gears between the two case sizes will not interchange. I could be wrong, but I think the 2.88 and 3.08 gears fit one case size and all the others fit a different case size.

I recall that 3.73 and numerically lower gears all fit the same case and you only run in to a problem when you're crossing the 3.73 threshold (like going from 3.54 to 3.92). But I'm not 100% positive, so check before you buy.

[ZOERA-SC7XX]

Originally Posted by patrickt

I recall that 3.73 and numerically lower gears all fit the same case and you only run in to a problem when you're crossing the 3.73 threshold (like going from 3.54 to 3.92). But I'm not 100% positive, so check before you buy.

Nope. The 2.88 posi rear comes from the XJS. The XJ6 uses the 3.07 and up and have a different case. How do I know? I made the mistake of buying an XJS rear and had to have the case changed out to give me a 3.31. I had Curt Hamilton in Ca. do the rebuild...he explained what I needed & what I had originally bought. Now I'm all set, although I spent some extra cash.

[patrickt]

Originally Posted by ZOERA-SC7XX

Nope. The 2.88 posi rear comes from the XJS. The XJ6 uses the 3.07 and up and have a different case. How do I know? I made the mistake of buying an XJS rear and had to have the case changed out to give me a 3.31. I had Curt Hamilton in Ca. do the rebuild...he explained what I needed & what I had originally bought. Now I'm all set, although I spent some extra cash.

OK, good to know. I stand corrected.

[RICK LAKE]

PeternPlymouth Welcome to the ERA family. First question the rear end ratio depends on what trans is in the car. If you have a 5 spd richmond the 2.88 or 3.07 is a perfect choice for the car. Great accelleration and nice cruise rpms. There are 2 center cases for the Jag Dana 44 rear. One is from 2.88 to 3.73 and the other is 3.92 and above. It's the inside machine work to clear the carrier gear. There are 4 different carriers for the Dana 44 Jag center section. The 2.88 is series 1. series 2 is ratios 3.07,3.31,3.54. series 3 is 3.73 and 4.09. series 4 is out the gate over 4.09. The mounting plate is different on the carrier for the correct back spacing in the different case. (Ring Gear) There are also different splines for the spider gears in the carrier. 27 and 30 are the strongest. Your Jag rear is good for a min of 450hp and torque. As long as you reframe from slicks on the car or smoking burnouts, the rear will be fine. A change of fluids every 2 years. If you want to beef it up, add a rear cover supporter for the caps in the carrier. You will need to add a vent tube to the cover. If you build up too much pressure in the rearend the oil will be pushed out the seals. As for the tire rub, 2 choices, either raise the height of the car with the springs. about a 1/2" you will need to get the car realigned after this, Get smaller tires to fit the opennings. When is the rubbing happening?? normal driving or spirited driving?? This will also decide if you need to improve on the springs and shocks. For the exhaust I have n't had the pipes fall off the car or the tab break on either pipe. I do install the pipes a certain way. I loosen all 4 header pipes and side on the mufflers with a little antiseize on all 4 pipes. I install the rear mount to the muffler. I then bolt and nut the tabs to each other. I finish by tightening the header bolts to the heads. The other thing to check is maken sure the motor is level in the car and not twisted. You may have to loosen the motor mount bolts, jack up the motor in the car, maybe an 1/2" and resettle it in the chassic. If the car is on a total flat area, I use a small level on the carb or intake manifold to make sure. Some guys have the L/s a little lower than the RS to acount for the torque of the motorunder spirited driving. You can get a small fiber patch kit from almost any auto parts store. Make sure you know how to install, prep the area, sand, seal, and paint or undercoat the car if not, Go find a good body shop to do the repair. I also use a small turnbuckle on my sidepipes at the rearend to support the pipes and keep them straight on the car. There is a little play for engine movement. Hope this helps Pete, Again welcome to the nicest family on CC. Rick Lake. If you have any problems you can call the Tech line and talk to Bob or Doug. They are both pros at helping fix a problem. Any thing else, Decooney or myself will be willing to help anytime. I'm on the east coast, he's on the west coast. You make want to look into the Watt's linkage for your car. My number is 732-254-3536 after 8:00pm est time. Good luck

[Jim Holden]

Ah, but if you are willing to go with the 2.88, it generally has a posi. Other ratios may not and would require a rebuild, etc.

Jim