'84 rear backspacing
#1
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Rotary Slave
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'84 rear backspacing
This is a 12A car, but the rear end will be to SE specifications. I seem to see a consensus in searches that 4.5'' is the maximum backspace for the rear on an FB, does this sound about correct? I will be getting a Ford 8.8 soon, and it is supposed to have same as factory flange spacing. I plan to run a 15x8 +4 in the rear. Do you see any issue with this wheel selection? It's a Rota RB, for what it's worth. Also, the front in order to match the rear, will either need a full SE swap, or hub adapters. I prefer the later since it's easier and cheaper by a long shot. This hub will be approximately 1'' thick, so I can get the Rota RB's that come in +25 and it should work out about right, front to back. Or maybe I should go staggered and run 7'' width up front. Not sure about the fit with the fenders.
Any pointers for me, or things to look out for/check while I'm going this road?
Thanks
Any pointers for me, or things to look out for/check while I'm going this road?
Thanks
#2
My 7 is my girlfriend.
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Depending on the total difference in the backspacing available between the SE's and lower models you may have an issue running an 8 inch wide RB up front. I've got the 15X8 RB's on my GSL and the fronts with a +20 offset require a 15mm spacer to fit.
#3
My car is a widebody (1984 GSL-SE originally), so the wheels are wider than yours will be but... My front wheels are 17x10 with 4.5" backspacing (TII big brakes), 4.5" backspacing seems to be about perfect for the front.
In the rear I have a grannys speed shop rear end and 17x12 wheels also with 4.5" backspacing. I wish I would have actually got a sligthly different backspacing like a 4", and got a 13" wide wheel. But 4.5" backspacing fits well.
Hope that helps.
In the rear I have a grannys speed shop rear end and 17x12 wheels also with 4.5" backspacing. I wish I would have actually got a sligthly different backspacing like a 4", and got a 13" wide wheel. But 4.5" backspacing fits well.
Hope that helps.
#4
4.5 is the ideal for track use which will allow the tires to clear the frame/inside panels during hard cornering. For street use, you can go with 4.75. I've fitted 5" backspace too but I feel that it is too risky
#7
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Rotary Slave
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Looks good, thanks! I would just go 15x7, but I need all the rubber I can get out back. I'm just worried about the front looking weird and sticking out too far. I think a +20 will be OK though, with the adapter which will likely be between 3/4'' and 1'' in thickness, so ultimately making the front more like a -5 overall. I might have to roll the fenders a bit.
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#8
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Looks good, thanks! I would just go 15x7, but I need all the rubber I can get out back. I'm just worried about the front looking weird and sticking out too far. I think a +20 will be OK though, with the adapter which will likely be between 3/4'' and 1'' in thickness, so ultimately making the front more like a -5 overall. I might have to roll the fenders a bit.
the front i have room for a 15x8, but 245's would be TIGHT
my car is a 12A car BTW.
#9
I think it looks far stranger when the rear wheels are wider than the front. Unless you are specifically using the car for drag racing.
#10
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Rotary Slave
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Rotordogg, I don't think it will be too noticeable with only a 1'' difference in wheel and 20mm on the tires. then again, now that I think about the extra weight I will have up front, maybe I should run a matched 8'' front and back, to avoid understeer.
This will be a 302 powered car btw. Yes I know, BURN HIM AT THE STAKE!!! Blasphemy!!! Sacrilege!!! and all of that jazz. I've had rotary power, and will again in the future, I just need something different for a change. Plus I like to learn new things, and OHV V8's are new to me.
#12
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Rotary Slave
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Yep, they do. But it doesn't suck having 275whp and about 325tq with just a few bolt-ons, and still getting probably ~25mpg (all for about $2500 total, engine plus bolt-ons). I just need a change in pace. I'll be back with a rotary eventually though. Really wanting another Turbo II, my last one never ran correctly and always had issues, so I never got to really enjoy owning a turbo rotary.
#13
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Yep, they do. But it doesn't suck having 275whp and about 325tq with just a few bolt-ons, and still getting probably ~25mpg (all for about $2500 total, engine plus bolt-ons). I just need a change in pace. I'll be back with a rotary eventually though. Really wanting another Turbo II, my last one never ran correctly and always had issues, so I never got to really enjoy owning a turbo rotary.
also there are a lot of valves and gaskets that leak and get stuck....
it actually doesn't take long to do either
#14
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Rotary Slave
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my START with a t2 is to pull the intake and check EVERYTHING. i have found that the vacuum diagram isn't good enough, so i actually unhook the vacuum hoses at each end and make sure they go where they are supposed to! it makes a big difference, each hose has a specific function. its actually really common to have the fuel pressure regulator hooked to a nipple that doesn't see boost, so it runs really lean
also there are a lot of valves and gaskets that leak and get stuck....
it actually doesn't take long to do either
also there are a lot of valves and gaskets that leak and get stuck....
it actually doesn't take long to do either
#15
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My T2 ended up with a full emissions delete. I think the problem was eventually fixed by the owner who bought it from me. It was linked to wiring, which is no surprise. Every wire on the car was heat rotted and would snap in half if I tried to bend them. It also had a bad exhaust leak from rusted exhaust. If I get another it will get fully stripped and rebuilt from the ground.
#16
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Rotary Slave
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So j9fd3s, you are running 225/45 on all 4 corners? I'm trying to figure out if a 15x8 +4 with 225/50 would fit up front without rubbing issues at full lock or over bumps. What say you guys? Trying to pin down exactly what I need for wheels before I go spending all this money on them. Seems that that wheel and tire combo is about a 4.7'' backspace.
#17
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So j9fd3s, you are running 225/45 on all 4 corners? I'm trying to figure out if a 15x8 +4 with 225/50 would fit up front without rubbing issues at full lock or over bumps. What say you guys? Trying to pin down exactly what I need for wheels before I go spending all this money on them. Seems that that wheel and tire combo is about a 4.7'' backspace.
in the front a 15x8 would be TIGHT, but i think it would work. the only thing in the front is that i'm running coilovers, and some camber, if you run stock camber, this will limit your tire size up front
#19
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if you run even -1 degree of negative camber, tire wear will be better, or about the same, and you'll have a TON more room to fit wheels and tires, because the tire will be leaning AWAY from the fender
#21
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Woohoo! Wheels ordered. I would have liked to have avoided a staggered setup, but on a daily driver with stock fenders, I decided I should go 7'' up front. Ended up getting 15x8 +4 for the rear, and 15x7 +12 for the front, in hyper black. This will be going on a dark grey car, so I think the hyper black will look really nice.
This color. Anybody know the paint code for this color, or what it is called?
This color. Anybody know the paint code for this color, or what it is called?
#22
the math is killing me here. i been trying to pin it down for months and asking but no good response.
so,
I got a 79' and I got 16x8 +20 wheels I plan on running 225/55 front and 245/55 rear and I really cant negotiate lower here since I got 400hp goals. I plan on doing wb in the future but just to get by without for now, which spacers do I need to fit without rub? Since I plan on running flares for this, how much will they stick out from the wells?
please help me out. i started two threads and responded with no results to a few others over the last 5 months.
so,
I got a 79' and I got 16x8 +20 wheels I plan on running 225/55 front and 245/55 rear and I really cant negotiate lower here since I got 400hp goals. I plan on doing wb in the future but just to get by without for now, which spacers do I need to fit without rub? Since I plan on running flares for this, how much will they stick out from the wells?
please help me out. i started two threads and responded with no results to a few others over the last 5 months.
#23
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the math is killing me here. i been trying to pin it down for months and asking but no good response.
so,
I got a 79' and I got 16x8 +20 wheels I plan on running 225/55 front and 245/55 rear and I really cant negotiate lower here since I got 400hp goals. I plan on doing wb in the future but just to get by without for now, which spacers do I need to fit without rub? Since I plan on running flares for this, how much will they stick out from the wells?
please help me out. i started two threads and responded with no results to a few others over the last 5 months.
so,
I got a 79' and I got 16x8 +20 wheels I plan on running 225/55 front and 245/55 rear and I really cant negotiate lower here since I got 400hp goals. I plan on doing wb in the future but just to get by without for now, which spacers do I need to fit without rub? Since I plan on running flares for this, how much will they stick out from the wells?
please help me out. i started two threads and responded with no results to a few others over the last 5 months.
i think if i took my car, which is 4x110, with camber plates and coil overs, can fit 15x8 20 in the back with a 245, and in the front the 15x8 20 is really close to the strut, but i think i can do it, and 225's are no problem under stock fenders, as that's what i'm running now. i don't see why 16's would really change much, it might actually make a 15x8 fit better in the front.
if you have the 4x114's its gonna stick out another 20mm, which is like an inch, and THEN you'd need flares or something.
the stock camber in the front is POSITIVE, so the wheel points OUT, so it really limits the tire out can run, even -1 degree has the tire pointing IN, which basically lets the tire tuck into the fender. its the difference between rubbing with 205's and having tons of room with 225's, in addition the stock camber wears the tires badly
#25
Heres my 85 gslse with 15x7 Rota RB wheels with +25mm and 205 50 15 tires. This can give you an idea of what it might look like~ They dont rub but I did roll the fender lips just in case.
vcs
vcs