upgrade to 8.8" or 9" rear on E-M

mg2166 · #1 (**permalink**) 02-24-2004, 02:04 PM

I currently have a Mustang II rear end on my Cobra with the MII leaf springs. I don't like it. Straight ahead she works fine. Cornering is another story.

I spoke with Bob at Everett Morrison, and it is possible for me to convert to their 4 link setup with a little welding and some parts they can supply.

My question is this. Do I keep my MII rear end, 8.0", or do I upgrade to an 8.8" or 9" rear.

I would really like to hear from someone who has done this. I remember a thread from the past year or two that discussed this very topic, but I have been unable to locate it.

Dan Stryffeler · #2 (**permalink**) 02-24-2004, 02:32 PM

I did the conversion to the 4 link during the winter of 2002. Was never quite happy with the handling or the stance of the leaf spring set-up... too big a gap between the top of the tire and the wheel flares - wanted that 'ERA' squat.

I kept the 8" rear only because I don't beat up the car that much and the rear tires don't hookup, i.e. they tend to spin, so why spend the $$$ - If I was doing it from scratch, would pony up for the 9".

We also narrowed it quite a bit, probably about 4 inches and moved the axle forward about an inch so that the tire sat forward in the wheel well a little.

Handling and apearance have greatly improved, very happy with the result. The only problem is that the panhard (panard?) bar wants to hit the trunk floor on hard bumps... we ended up putting a "Gurney Bubble" in the trunk floor to get rid of most of the problem. The side of the trunk towards the front also had to be relieved a bit to accomodate the tire, but no big deal.

Yeesh... third edit - but, I also did the conversion to a disc brake setup at the rear while I was at it.

If you go this route, be careful... EM has the coil over shocks pretty much straight up/down. You want some angle in there or you will have a very bumpy ride - follow the installation instructions from the coil over manufacturer.

Not a great picture, but if you look at my gallery, you can see what she looks like now, (have added a roll bar since the picture was taken).

- Dan

rbray · #3 (**permalink**) 02-24-2004, 03:28 PM

Dan,
Thanks for the information on the Panhard bar. I have an EM with the 8.8 four link setup and I have been experiencing an unexplained bump .... maybe I have the same problem you had.

Mg,
When I spect out my EM they told me the car would handle better with the 8.8 , but the 9" would make a better drag racer.
I'm really happy and some what surprised at how well my EM handles. I have the Aldan Eagle coil overs all the way around as well. Good luck with your conversion.

mg2166 · #4 (**permalink**) 02-24-2004, 05:17 PM

Dan,

I try not to abuse my cobra either. It is used for cruising, not racing. I was leaning towards keeping the 8", so I'm glad to hear it works well for you. I also had trouble getting the rear tires to hook up until I let the air out of them. I am now running 25-26 PSI. She hooks up better and even corners better. You mentioned that you upgraded to disc brakes at the same time. How did you accomplish that? Thanks for the info.

Rbray,

Thanks for the info and the encouragement.

Dan Stryffeler · #5 (**permalink**) 02-25-2004, 10:38 AM

Mark,

I've got all the receipts at home, will dig the stuff out and repost on the same thread asap.

It was relatively simple... while they were narrowing the rear housing, they cut off the old flanges for the drum brake backing plate and welded the new flanges on. After that it was pretty much a bolt-up conversion. Had to redo the parking brake cable, which still doesn't work all that well.

Roger,

If I hit a bump with the left side or right side independantly, I was ok... if both tires hit a bump, thats when the panhard bar rod end would hit the trunk floor. Its mounted on the top of the differentail.

- Dan

mg2166 · #6 (**permalink**) 03-01-2004, 10:23 AM

Dan,

When you did the rear end conversion on your E-M, did you have to remove the body in order to weld the brackets to the frame?

Mark

Dan Stryffeler · #7 (**permalink**) 03-01-2004, 01:41 PM

Mark,

I'm sorry... I forgot all about pulling the part/kit numbers for you, will do it tonight.

I had wanted them to remove the body when they did the conversion, wanted to touchup the frame and engine compartment, but the builder did it with the body on... apparently, it wasn't a problem for them.

- Dan

Dan Stryffeler · #8 (**permalink**) 03-02-2004, 06:22 AM

Mark,

Dug out old invoices;

The disk brake kit was from Master Power Brakes, P/N DB1517B

http://www.mpbrakes.com

The axles were from Moser, P/N BSPN-147 - I don't think that these are a standard part... my rearend was narrowed quit a bit. I think that the housing ends (flanges) were also from Moser; the part number that I have is 7755 and is described on the invoice as "Small Ford Housing End"

http://www.moserengineering.com/

I have the blueprints from EM on the 5 link if you want to email me a mailing address.

- Dan