One of my most interesting and most likely to happen fantasies is an RX7 with an SBF. Recently read where an Explorer makes a great donor for this. Engine, tranny, 8.8 posi rear end. If I do this insanity, it will be a bucks down project, so the automatic will be a part of the deal. My question is that the Ford automatic is seemingly not very stout. Can they be set up to handle 350-400hp? What Pagan Majic is necessary? Thanks, all.
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Nov. 8, 2011 6:21 p.m. cwh SuperDork
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Nov. 8, 2011 6:32 p.m. ransom Dork
You're planning to keep the auto for cost only? Surely you can sell off an Explorer auto (especially if they're not that stout and people are killing them in their Explorers towing and such) for enough to pick up a 5-speed out of a Mustang, or at least be within a six-pack or so...
And I apologize, I'm stepping on one of my own pet peeves wherein a peson asks the Internet "How can I achieve A?" and some shiny happy person (in this case me) says "A? Are you out of your mind, why aren't you doing B?"
I just can't help myself in this case. I'd love to do a V8-powered FC RX7, but an auto would just kill it for me...
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Nov. 8, 2011 6:34 p.m. Greg Voth HalfDork
Our Lemons car is a 83 RX-7 with a 302, T-5 and 8.8 Rear end. We bought it in almost running condition for $500 plus a cage and race seat for another $700. A fuel pump I pulled off another RX-7 got it running. The rear we got off craigslist for $200 and welded from the RX-7 rear onto the 8.8.
T-5's can be had pretty cheap. I just bought one last week for $150 sans bellhousing. Manuals make everything more fun.
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Nov. 8, 2011 7:01 p.m. aussiesmg SuperDork
Not done cheaply, 5.0, T5, RX7 rear end. Weighs within 20lb of stock weight for 84 GSL.
long tubes fit
slave cylinder
teaser
http://s869.photobucket.com/albums/ab256/aussiesmg/RX50/?action=view¤t=0...
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Nov. 8, 2011 7:09 p.m. familytruckster Reader
The explorers use a 4R70W trans. They can handle 400hp easily. However, unless you find a 2wd V8 exploder you will have to rip the trans bare to swap the output shaft to a 2wd shaft and housing.
I used a 6 cyl (less clutches) 4r70w as a donor for my wide ratio AOD, and that trans has stood up to a few seasons of autocross and a lot of hard miles and it still is like brand new. This is on a 4500lb 245rwhp wagon.
Even the old AOD could be stout, just toss in a good VB.
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Nov. 10, 2011 7:20 a.m. just_james New Reader
I thought the Explorer's 8.8 was offset to one side and had different axle lengths. Maybe we're thinking of different model years since they were made for a long time.
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Nov. 10, 2011 8:18 a.m. Curmudgeon SuperDork
Toyman and I did some measuring; the rear axle in the ThunderTerd (1986 Thunderbird LeMons car) is almost exactly the same width (~57") as a 1st gen RX7 piece and the Fox body Mustang axle is the same width as well.
Here's the cool part: there is a 29" long Ranger/Explorer rear axle shaft which, if you grab 2 of them, converts the 4x108 Fox body T Bird or Mustang rear axle to a 5x114.3 and there are all kinds of bolt on rear disc parts available from Crown Vics, Exploders and the like. (The Ranger/Explorer rear axle assembly is 54", too short.) There's lots of rear axle ratios and limited slips available either boneyard or new for that same axle.
Then you grab the front struts and front brake stuff off of a 5 bolt 2nd gen RX7, stick that on the front of a 1st gen and voila! 5x114.3 bolt circle all around with 4 pot front calipers.
Then stuff in the V8 of your choice and roast the tires.
Yes, I am an enabler.
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Nov. 10, 2011 12:30 p.m. Greg Voth HalfDork
We have the T2 RX-7 brakes on the front of our car. You can get the RE-Speed kit (awesome experience with ours) for $300 ish with SS brake lines. You could fabricate your own adapters or swap in the entire second gen subframe but you then need to figure out engine mounting again.
Since no-one else has mentioned it grannys speed shop is the place for the engine mounting kit. Its pretty simple but worth the money saving the headaches of figuring out mounting points.
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Nov. 10, 2011 12:52 p.m. Curmudgeon SuperDork
ReSpeed's kit is nice but only works with the late 1st gen strut housings. About swapping the front brakes and struts: my thought was (and I need to do some measuring): use the 2nd gen/T2 front strut housings but cut them off, remove the guts and use the 1st gen replaceable inserts in those housings. The 2nd gen ball joints can easily be adapted to the stock 1st gen lower control arms, meaning using the 2nd gen knuckles too.
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Nov. 10, 2011 2:32 p.m. weedburner New Reader
'86-'98 Mustang/T-bird 8.8 solid axle housings are all the same tubeflange/tubeflange width of 54.10". '99-'04 housings are a little wider at 55.51"
Overall wheelflange/wheelflange widths for the FOX 8.8 varied... ...86-'93 Mustang 59-1/2" ...'94-'98 Mustang 60-7/8" (same housing as '86-'93, but uses .705" longer axles to make room for ABS tone rings)
Left side Ranger axles are the ones used for the cheap 5 lug upgrade, and are 28 spline. Explorer axles are not compatible with the FOX housings (different bearing size).
1st gen RX-7's used 2 different width rears... ...'79-'85 12A cars w/ 4 on 110mm lug pattern is 56-3/4" AF/AF (add 1/4" for drum brakes, add 1/2" for disc) ...'84-'85 GSL-SE w/ 4 on 4-1/2" lug pattern was 58-3/8" w/ rotors
A 58" WF/WF rear is almost perfect for fitting big wheels/tires for the drag strip, as it enables you to use common offset wheels (15 x 8" w/ 5-1/2" backspace wheels and 275/60-15 radials can fit)
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Nov. 10, 2011 5:06 p.m. Curmudgeon SuperDork
I don't recall the exact measurements but I knew it was real close. I had a 1st gen axle standing in the shop when we were measuring, scratching our chins and talking over eVil plans...
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Nov. 10, 2011 6:50 p.m. aussiesmg SuperDork
Mine is still running the 1st gen RX7 rear, its a lottery but some RX7 rears are running 8's.
