Build Thread '83 T-top Coupe - Welding Holes in My Rear
- Thread starter Davedacarpainter
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Actually Mike, i'm going to list it on Facebook this weekend. I don't like the site, but if it helps move out some of the extra stuff, I'll give it a go.
Ok, let's forget the mini-tub idea just for a moment.
IRS upper and lower control arms, couldn't I really just make my own? I have a nice flat metal table I could weld a jig on.
What type of steel tubing would work the best. Chrome moly?
Ok, now remember the mini-tub again. Couldn't I just disassemble the half shafts and send them to Moser or Strange and have them shorten them and re-spline them? Why find a hole new set?
IRS upper and lower control arms, couldn't I really just make my own? I have a nice flat metal table I could weld a jig on.
What type of steel tubing would work the best. Chrome moly?
Ok, now remember the mini-tub again. Couldn't I just disassemble the half shafts and send them to Moser or Strange and have them shorten them and re-spline them? Why find a hole new set?
- Mar 2, 2015
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I think a bad a$$ ideas would be to actually widen the car. To split the quarters beside the rear window and bring the whole side out 2 inches at the wheel well upper. Split the doors and widen them.... then the front fenders. Split the front and rear bumper covers and add a couple inches. No one that i know off has done that. The hood, trunk, and roof would stay the same. The tail lights would move out to match the widened quarters.
I bet it'll be easier for you to do that than to shorten the IRS. If done right it could be great.... and something completely different.
If i had your skill this is the path my mind would take me in. Remember the old Pontiac commercial, " wider is better ". I bet you could do it where no one would even figure it out at first glance.
I bet it'll be easier for you to do that than to shorten the IRS. If done right it could be great.... and something completely different.
If i had your skill this is the path my mind would take me in. Remember the old Pontiac commercial, " wider is better ". I bet you could do it where no one would even figure it out at first glance.
It's not just making control arms, but also redesigning how the wheel travels through its arc and shock/spring mounts and rates. A bit more complex.
Why not a little extra body work like matt Farrah's notch?
If I were to copy the stock locations for everything, just use tubes instead of that monster aluminum lower, do you think that would still be problematic?It's not just making control arms, but also redesigning how the wheel travels through its arc and shock/spring mounts and rates. A bit more complex.
Why not a little extra body work like matt Farrah's notch?
Problem is you've shortened the moments which require revised spring and shock rates. Coilovers out back would be best answer, but now you've got that cost as well. Between that, the IRS, and the custom half shafts and arm, your are gonna have a $2.5k rear when done...and no guarantee it will work as well as it could.
I mean...this solution is a tad extreme but it can also be done. How much work do you want to put into this?
I mean...this solution is a tad extreme but it can also be done. How much work do you want to put into this?
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Another thing to think about is the closer the tire goes inward, the closer to the rear subframe bolts which protrude out a bit
That's very kind of you to say, and I'm very impressed that you're even considering fabricating your own suspension. I'm sorry to say that this sort of thing is outside of my wheelhouse, though I like soaking up the experience of others. I'll just throw in a couple of observations that I haven't seen already addressed. What you've put forth should work, but if the differential housing to the wheel hub center is not in line, then shortening the rear track increases the angles of the CV joints to compensate for the offset. I would measure/calculate the range of possible angles and ensure they are well within the CV joint limits. A quick search turned up CV joint types and common limits: http://www.gknservice.com/gb/passenger_cars/constant_velocity_joints.html
From what I've read on the subject of improving fox handling, the big players spend a lot of time trying to eliminate the understeer, meaning that it's the front suspension and tire that needs the most improvement. And, before you entirely convince yourself that IRS is the way to go, I'd encourage you to read this from Bruce Griggs: http://www.griggsracing.com/pdfFiles/IRS vs Stick Axle Debate.pdf
Though it would be pretty awesome to see someone customize their own suspension, my gut says it will be be chalk full of unforeseen issues, less effective than off the shelf systems, very time consuming, and ultimately more expensive. So, the coolness of doing it yourself and the props from us on your fab skills are the only upside I see.
Hummmmm........that Griggs article is interesting.
Got to admit, tubbing would be far easier with an SRA.
Admittedly, a panhard bar on a narrowed SRA takes a bit of ingenuity, but not as much as narrowing an IRS.
No firm decisions here yet, but selling the IRS would be relatively easy for the same money I paid for it.
Hummmmmm.......
I hadn't considered the CV joints at all either, I'm betting that alone would take out the idea of narrowing the control arms and axles.
Parts are pricey for the IRS too. A good delrin bushing kit runs over $700. Then there's the upgraded toe links. Plus if I want control arms, there goes $1400. Lord knows halfshafts aren't cheap either. These costs are more than an entire MM front suspension, and I want that as well.
Plus if I stayed SRA i wouldn't get my thread moved around by @CarMichael Angelo for those Wild Rides torque boxes.
Things to consider. Thanks for chiming in Chris.
Don’t worry dave,as long as mike doesn’t put it in tech. I can move it back for ya 
10,000 years from now, the aliens will come down and find this heap of springs, body, and suspension parts. It'll be another thousand years before aliens are able to solve the riddle of "The Conveyor Pod With No Ass" which in alien, sounds like:
View: https://youtu.be/sWtBE0T6eD8
View: https://youtu.be/sWtBE0T6eD8
I haven't done any official measurements yet, but the inner fender is now the limiting factor as the mount now sits slightly inside that.
And Dave, just for your reference, this is what I am doing (though more polished and not quite as racy looking). I will be blending the rear quarter panels into the bodywork instead of riveting them to the body. With the fender flairs and hard tail mount, I can fit a 335 in the rear, though I will probably run a 315 to match my front. My front end will be a MM based road race setup with 1.5" forward offset control arms, with the matching fender flares. The front end of the mustang suspension is really where you have to pay the most attention, for handling purposes that is.
I remember reading that article when it came out (07) as I used to run all Grigg's components on my 95' cobra. Back then, I drank the Grigg's coolaid and couldn't believe there was anything better then what he recommended (not knocking him, he does know what he's talking about). I've had an SRA with a watts link and T/A, and it is amazing on the track. I've also driven fully track prepped mustangs with IRS's on the track, and after that, I don't think I would go back to an SRA. As I've always said, a properly tuned SRA with a watts link and T/A can put power down coming out of a corner way better than an IRS. On a flat track with no curbing, I don't think either would out perform each other. With an IRS on the tracks I normally run, I found I could enter the corner faster and follow a different line (use more curbing), which meant I left the corner faster and didn't need as much ability to put power down coming out of a corner. I finally got to ride in a street based foxbody with an IRS swap a month or two ago, and have to say the ride quality was much better than with an SRA.
Dave, IMO, you really need to decide what you're ultimately going to do with the car. If you main goal is getting power to the ground and running a wide tire, I'd stick SRA with a panhard/watts and TA. If you want a nicer ride on the street and a slightly smaller tire, run a build IRS. If you're planning on road racing, go with a built IRS, widebody, ect.
Just my 2 cents.
How freakin' cool is this^^^^^ a road race Mustang wearing Monster colors? I'm thinkin I like the satin paint line going over the roof.I haven't done any official measurements yet, but the inner fender is now the limiting factor as the mount now sits slightly inside that.
And Dave, just for your reference, this is what I am doing (though more polished and not quite as racy looking). I will be blending the rear quarter panels into the bodywork instead of riveting them to the body. With the fender flairs and hard tail mount, I can fit a 335 in the rear, though I will probably run a 315 to match my front. My front end will be a MM based road race setup with 1.5" forward offset control arms, with the matching fender flares. The front end of the mustang suspension is really where you have to pay the most attention, for handling purposes that is.
Dave.....Plane ticket time?
IMO Griggs is an IRS hater. He doesn't want to compete against MM and FTBR with R&D of products to upgrade the Cobra IRS. It's also not a huge market since there's not an abundance of desirable 03' & 04' Cobra IRS units. There's a sh*t ton of 8.8 SRA's though and they work well on the track and that's been proven time and time again. If you talk to anyone from Maximum Motorsports or even read the tech info from Bruce at Full Tilt Boogie Racing you'll find that they love both and either design has their strengths and weaknesses.
With all that said I believe you're getting in to the IRS for all the wrong reasons. The IRS in stock form has more design flaws working against it than good. The geometry is also not the best either. MM & FTBR has remedied these flaws. I think you're taking something that has flaws and you're going to make it even worse by narrowing it. IMHO, I think @Hoytster has the right idea, the hard tail mount is the way to go and blending small flares is the key to get 315 or bigger out back. This is a corner carving modification though, not a street car with big'n little's type mod but it's a free country and you can do whatcha like.. Seems to me that the hard tail mod gets you back to the wheel widths of a factory SRA but with a different backspacing. So an 18x10 with maybe a 285 tire without doing anything to the fender except rolling the lip. If you want more, and it seems you do, I'd stick with an SRA with a mini tub.
Function + form= winning!
Function - form= meh, it works though
form - function= show car, trailer queen
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