MAXIMUM OR GRIGGS???

[rppngears91]

Didn't MM bolt in a IRS to thier shop car and with a day or two of testing go faster then they did with the 3 link? Have they stayed with the IRS or did they switch it back?

 

Brian[/quote.]

 

Ive recently talked to MM, they didnt exactly just "bolt it up." A lot of fabricating was involved because the rear subframe in the Fox's are not designed the same way a newer Cobra rear subframe. And then after tuning and tweaking the rear (toe, camber ect..) for probaably a LOT longer than just a few days. And in the end they discovered the IRS is both faster AND slower. According to MM the IRS set up is MUCH faster on a more bumpy and higher birms type of track. But on smoother flatter tracks the 3 Link is superior. For example this year at Mid-Ohio Mr. Andrews (3-Link) was able to obtain faster laps because of the condition of the track. Also like XAIX states, it is very heavy and complex. But MM states that at thier home track (Buttonwillow) they were able to achieve MUCH faster lap times with the IRS. The right amount of track time and tuning knowledge are required in order to properly run the IRS at its best.

 

XAIX,

 

I dont mean to disagree with you simply because I cant. I dont have first hand exprience with racing IRS vs a 3 Link like you. Im just passing on the info Ive gotten from the guys over at MM

[92MNstanger]

Not that I have any business posting in this conversation, but...

 

I have a 92 lx with a stick 8.8 and get it aligned locally. One thing that always bugs me is the readout for the rear (I swear the techs do this just to bug me). I have the MM weight jacker arms and I always seem to have a bit of toe-out on one side of the car and toe-in on the other side. Camber is negative (old car) but unequal from side to side. I will admit these differences may be within the %R&R of the gage used, but it would be nice to set the camber and toe of the rear to "something" other than looking at the print out and sighing.

 

Oh yeah, MM for great customer service and durable parts.

[Ernesto Roco]

Sounds to me like you need to square up your rear axle.

 

Also, never trust those Pep Boy's alignment. Either learn to do it yourself or take it to someone who knows what they're doing.

[trackboss]

Factory axle housings are not very straight. Don't be alarmed it not unusual. The car will perform better however with a proper, jig-built, rear end with desirable and true alignment.

[92MNstanger]

Sounds to me like you need to square up your rear axle.

 

Also, never trust those Pep Boy's alignment. Either learn to do it yourself or take it to someone who knows what they're doing.

 

I trust my alignment guys. Why do you say they don't know what they are doing?

 

 

It's not a Pep Boys. There would be concern if I had the alignment checked after pulling the car off the rack and we got radically different numbers. I have had the alignment checked after events and gotten the same numbers (within a tenth) time after time unless I was off track. The alignment rack is just a big gage. No gage is perfect, but a properly trained person operating an alignment rack is not going to be any worse than a home alignment. They have 0.1 degree resolution and can hit the numbers repeatedly.

 

The reason they show me the data from the rear axle is to explain why they had to "interpret" the car's thrust angle.

 

I have no issues with the alignment. I have issues with my 8.8 and/or torque boxes. I was just trying to point out that with an IRS something could be done to tweak the rear more easily than buying the rear end mentioned above.

[Ernesto Roco]

You say you have the MM LCA, why don't you correct the bad thrust angle with the rod end adjustment?

 

With the panhard/watts link you can correct the lateral location of the rear axle.

[white_2kgt]

I have no issues with the alignment. I have issues with my 8.8 and/or torque boxes. I was just trying to point out that with an IRS something could be done to tweak the rear more easily than buying the rear end mentioned above.

 

So weld up your torque boxes (you'd need to do that w/ either IRS or 8. and pull your 8.8 and put it in a jig to get the alignment the way you want. If you go w/ an IRS you better enjoy getting alignments b/c you will have to align the IRS before every track outing and maybe even at the track to keep it where you want it. I have always used the MM TA/PHB setup but next season I may be switching to an IRS just for kicks. I have the IRS but it hasn't been built up yet.

[92MNstanger]

You say you have the MM LCA, why don't you correct the bad thrust angle with the rod end adjustment?

 

With the panhard/watts link you can correct the lateral location of the rear axle.

 

The MM weight jacker arms are fixed length. What equipment are you using to align your car?

 

So weld up your torque boxes (you'd need to do that w/ either IRS or 8. and pull your 8.8 and put it in a jig to get the alignment the way you want. If you go w/ an IRS you better enjoy getting alignments b/c you will have to align the IRS before every track outing and maybe even at the track to keep it where you want it. I have always used the MM TA/PHB setup but next season I may be switching to an IRS just for kicks. I have the IRS but it hasn't been built up yet.

 

Do you recommend welding up the torque boxes even if there is no visible damage to them? I only mentioned them for the sake of factory tolerances from side to side possibly contributing to this issue. I was under the understanding that with MM's spherical bearing on those arms and a three link the stress on the torque boxes would be less than in a stock configuration.

 

Do you have an on-line resource or book to reference for aligning and 8.8?

[white_2kgt]

You say you have the MM LCA, why don't you correct the bad thrust angle with the rod end adjustment?

 

With the panhard/watts link you can correct the lateral location of the rear axle.

 

The MM weight jacker arms are fixed length. What equipment are you using to align your car?

 

So weld up your torque boxes (you'd need to do that w/ either IRS or 8. and pull your 8.8 and put it in a jig to get the alignment the way you want. If you go w/ an IRS you better enjoy getting alignments b/c you will have to align the IRS before every track outing and maybe even at the track to keep it where you want it. I have always used the MM TA/PHB setup but next season I may be switching to an IRS just for kicks. I have the IRS but it hasn't been built up yet.

 

Do you recommend welding up the torque boxes even if there is no visible damage to them? I only mentioned them for the sake of factory tolerances from side to side possibly contributing to this issue. I was under the understanding that with MM's spherical bearing on those arms and a three link the stress on the torque boxes would be less than in a stock configuration.

 

Do you have an on-line resource or book to reference for aligning and 8.8?

 

I'd weld them up just as a matter of prepping a chassis for racing, much like subframe connectors.

 

Any competent shop should be able to setup your 8.8, it will most likely have to be pulled out and stripped down so they can heat it and straighten it properly. If you are looking for alignment specs sorry I don't have any of those for you, from what I've seen most people just run them straight.

[RACINRICO]

Well thanks for all of the input. I ordered my 03 cobra rear end today. i dont think weight will be an issue. my brother is a front end & supension tech at for & he said that me can make some major adjustments to help it handle much better. so we will give it a try. like i said THANKS AGAIN for ALL of the input here. see ya out there.