IFS/IRS swap bolt pattern issue

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nohotrod
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IFS/IRS swap bolt pattern issue

Post by nohotrod »

I am looking at swapping a 2008 CV IFS and a 1996 T-Bird IRS setup into my 69' F100. The problem is that the CV has a 5x4.5 bolt patern and the T-Bird is 5x4.25. I would like all four wheels to have the same bolt pattern.
Any suggestions?
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convincor
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Re: IFS/IRS swap bolt pattern issue

Post by convincor »

Yes, Send them to Stu. He's does all the redrilling of these hubs for FFR Cobra replicas. He did mine. :thup:
http://irsmachining.com/

Another option would be to use 99' Mustang Cobra hubs.- http://www.breezeautomotive.com/details ... &cat_id=36
Cost wise it's a no brainer, redrill yours. The other thing I don't like about using the Cobra huds in that the center spigot is bigger than the t-bird part. So the centers of your t-bird rotors need to be machined bigger which will need to be done on a lathe vs taking a T-bird rotor and enlongateing the bolt holes which can be done by hand and the rotor will still be hub-centric. Cheaper and easier in the long run.
Now with all that said, :nopix:
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Re: IFS/IRS swap bolt pattern issue

Post by nohotrod »

I read in another forum that the T-Bird/Cougar IRS will not work with the CV IFS due to different ride heights. I interpreted this to mean that either the front or rear of the truck will sit higher or lower than the other. Is this true and is there any options to use both the IFS/IRS combination?
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convincor
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Re: IFS/IRS swap bolt pattern issue

Post by convincor »

I'm search'n for your answer. so far I've come up with so pics of it down but not sure on the ride height issue.
pics- http://s15.photobucket.com/albums/a358/ ... /?start=40
Did you see this? http://team321.com/truckirs/HomePage.html
68 Custom Cab Shorty, 390, C6, 9"-3.50:1 Currie T/L
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Re: IFS/IRS swap bolt pattern issue

Post by nohotrod »

I've been some research also between different forums and not finding an answer yet either. I'm gonna call TruckIRS.com tommorow and ask if they have solved this problem.
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Re: IFS/IRS swap bolt pattern issue

Post by fuzzier1 »

Here is a thread that you should look at. He started installing an IRS on page 5 of this thread. It is not a bolt in project but it can be done. Go here for the entire thread http://www.fordification.com/forum/view ... vic+diesel. He has a MUCH larger write up (last I checked, 66+ pages) over at the darkside. While I don't like sending anyone there it is well worth the read. I am planning this for my 71 SWB this summer. Very cool truck.

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Re: IFS/IRS swap bolt pattern issue

Post by nohotrod »

I spoke with Dave at TruckIRS.com and he said that his installation kit (to install IRS) will lower the rear of a 56' Ford truck 5". Is the frame the same or similar between a 1956 and a 1969? From what I have read, a Crown Vic engine cradle assembly will lower the front of a 1969 5". I also changed my mind and went with a 1998 Lincoln Mark VIII IRS whick is the same as the T-bird but has the aluminum differential. I paid more than I wanted for them but I was having a hard time finding them. I hope this setup works, I'm sure it will, without too much fabrication.
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Re: IFS/IRS swap bolt pattern issue

Post by 1lowf150 »

i like the thunderbird irs i put in my truck. i modified the stock cradle to bolt to my frame, however i used a 89 cv front clip and built my own frame. figure out what ride hight you want the truck to have, set it up there and make everything else work at that height. you may have to z the frame in the front. i redrilled the rear hubs myself, but we have a mill and rottory table for it. i would think any machine shop could do it, just press the hub apart and go pickup the new wheel studs so they have all they need. if i get to build another truck i would go the later model front suspension.
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Re: IFS/IRS swap bolt pattern issue

Post by nohotrod »

I love it. I am thinkng of finding another truck to do this swap on as my 69 f100 is very clean and I don't know if I want to "cut it up". I will hold on to the 08 CV front end and 95 Mark VIII rear end for now until I can do some more research and make my final decision. Also, I am planning on taking my truck on the Hot Rod Power Tour again this year and I don't know if I could have the swap finished in time. I would hate to have to ride with my buddy in his 72' Chevelle. I am the type of guy that jumps before he looks, so I am trying to be patient and think this completely through first. It's killing me to look at these parts and not start doing something with them. 5" doesn't sound too terrible but that is a pretty good drop. Also, I like the look of the Boss 338's I have seen on other trucks, so I have been loong at these and trying to determine backspacing. From what I can tell, I thing a 20mm offset is what I need. I would like to run 20" x 8" or 9"s. Maybe 20"x10"s if they will work. Do I really want to do this and keep the three in the tree. I don't know, we'll see.
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Re: IFS/IRS swap bolt pattern issue

Post by convincor »

I'm in the same boat with my 68. Not going to do any major mods to this frame. Except I am working on a "bolt in" 4-link set-up though. It'll use all factory holes and no welding..
As for the IFS/IRS, that's going to be another truck. Another shorty. Going to venture into a IRS similare to what FFR uses with tubular control arms.
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And thinking it'll get FORDS new Hurricane 6.2L when it comes availible. :evil:
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Re: IFS/IRS swap bolt pattern issue

Post by 72-F100-4V »

I was the one on the dark side that posted the IRS would not work with the truckirs.com brackets. There is nothing wrong with the parts I received as they will work as advertised, I unfortunately was trying to use them with a front suspenion that had not been tried with the brackets (Panther IFS from a 07 Marquis). I had it all mocked up as Dave told me (he helped me over the phone that day) and they came up short, again nothing wrong with the brackets.
Fast forward some time and carcrafter22 pulled it off, without brackets, by cutting off the mounting ears and welding it up to his boxed in frame. Proved me way wrong. My hat is off to him!
Ive been studying carcrafter22's photos and plan on tackling the IRS install once I get home from this deployment. Ive been researching CV axles, and have been thinking about building a jig to widen the IRS cradle, which would need longer CV axles. This would be to eliminate the need for the wheel adapters to widen the IRS track width. Though there seems to be a even split of opinion on the use of adapters, which leads me to just get some, have a channel milled between the lugs and safety wire them and forget it.
**
Here are 3 great sites for info on what parts to get to rebuild the IRS suspension, How to strengthen the IRS, and a wheel size calculator with the particular sizes of 18's I would like to use. If I were not to use adapters and had the coin to spend on wheels I would need a -19 offset rear wheel for it to have the same track width as the front. Ive priced everything through rockauto for the rear suspenion rebuild and it comes out to exactly 445 dollars with the 5% discount, this would be for the brake lines, and the parts outlined in the TCCOA thread. That does not include the Cobra hubs, Cobra rear rotors, caliper brackets, new bearing, or hub nuts, differential mount bushings, 4.10 gears, gear install kit, that I already have at the house waiting for this install. Or the cost of the 93 Mark VIII IRS assembly.
**
http://forums.tccoa.com/showthread.php?t=99795
http://www.rims-n-tires.com/rt_specs.js ... Wheel-Tire size comparer&showRim1=1&showTire1=1&sw1=275&ar1=45&bd1=18&rd1=18&rw1=10.0&et1=-19&showRim2=1&showTire2=1&sw2=255&ar2=45&bd2=18&rd2=18&rw2=9.0&et2=20&text1=&text2=
http://www.tccoa.com/articles/mn12how-to/irs/irs.html
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