body/frame dimensions...weird!!!

[yannis-supras]

I'm in the middle of a major restoration and I'd like to ask about something I came accross. This is a question I intend to make to the Toyota production department if I can ever manage to.
Well my own mk2 has rusted quite badly (beyond repair I believe) so I managed to find ,what I think, a very clean '85 car. The car has been restored 5 years ago and it is very clean in all the usual rust prone spots. As I'm trying to do this the right way, I'm trying to restore this to as close to perfect condition. So the car has been stripped down to bare metal. Fenders, all glasses, windows, doors, linings, everything. So being the perfectionist I am I asked the bodyshop guy (who, for my good luck happens to be a perfectionist as well) to measure all the body/frame dimensions so as to check and see if the car has been damaged in a car accident or anything like that. On the front end every single dimension is perfectly lined up to factory spec. When he measured the windshield diagonals though there was a dimension difference.
Looking the car from the outside straight ahead, the top left (passenger side) to bottom right (driver side) diagonal of the windshield is 3mm longer than the opposite diagonal.
http://i15.photobucket.com/albums/a358/Yannis440/windshieldsmall.jpg
Forgive me about the confusion on the image above, the blue text was suppose to be on the other diagonal, couldn't fix it after I goofed :rolleyes:
The roof and pillars of the car from inside out have no signs of repairs or any other non factory weld, notch, anything. Nor is there anywhere else on the car any sign of the functional/main body areas been repaired. My question is, is there the possibility that this is a factory flaw that was considered as "within spec" by Toyota and was let out the production line or is it something I have to be concerned with. I'd like to underline that every other single dimension on the car is exactly as the TSRM states, not even 1mm difference.
I apologize about the long post but I wanted to give a clear picture of the problem.

[sarinas_dragons]

My guess is a slight collision to the passenger's side. Those measurements guide a frame tech when performing a "pull". A pull is when a car is set-up on a frame rack and force is applied opposite the direction of the collision. After the measurements are taken the affected area is then pulled with hydraulics until the measurement is correct again and stabilized.

The fender has probably been replaced. There is a chance that was all but ...

Alot of times this type of damage will also make the rear tires follow in a different path than the front tires. If possible, follow the car while someone else drives it. Try to notice if the rear wheels follow a line slightly to the right of the front wheels.

If the wheels track the same then the damage is not too bad. But if the wheels don't track the same then my guess is even more of the car was involved. Compare the sealer that is used to seal the body joints on the passenger side of the engine bay. It should look exactly like the driver's side. Also look for wrinkles in the metal. The hood when closed should have the same gaps on both sides. Take your time when looking and you will probably start to see the small differences.

Good luck.

[yannis-supras]

My guess is a slight collision to the passenger's side. Those measurements guide a frame tech when performing a "pull". A pull is when a car is set-up on a frame rack and force is applied opposite the direction of the collision. After the measurements are taken the affected area is then pulled with hydraulics until the measurement is correct again and stabilized.

The fender has probably been replaced. There is a chance that was all but ...

Alot of times this type of damage will also make the rear tires follow in a different path than the front tires. If possible, follow the car while someone else drives it. Try to notice if the rear wheels follow a line slightly to the right of the front wheels.

If the wheels track the same then the damage is not too bad. But if the wheels don't track the same then my guess is even more of the car was involved. Compare the sealer that is used to seal the body joints on the passenger side of the engine bay. It should look exactly like the driver's side. Also look for wrinkles in the metal. The hood when closed should have the same gaps on both sides. Take your time when looking and you will probably start to see the small differences.

Good luck.


Hmm, as I said this is so weird because we have checked the whole car and there's no sign of repair on structural parts, no misallignment, not the slight difference in any other body/frame dimensions. The bonnet and fenders line up perfectly and there's no deviation of the factory spec dimensions anywhere else but the one of the two windshield diagonals. We checked the roof joins to the c-pillars and they are untouched. The sealer looks identical all around. All these signs you hinted out were under our knowledge and we checked for them meticulously. It is because all these seem to be in perfect factory condition that makes this a big puzzle... :frown:
I've spoke with Phill Dupler which I consider a very knowledgeable person in bodywork and his opinion was this: "...over the years and miles an old unibody chassis like ours is going to "torque" a little and the dimensions between the roof and the lower part of the body are exactly where I'd expect to see any deviation show up first...", I don't know maybe that's the case...

[sarinas_dragons]

If the car was damaged when it was new or near new there would have been every effort spent to make the car as perfect as possible. Deformity could be caused by age and torque but that is such an isolated location. If it doesn't bother you and isn't noticeable and doesn't leak then you're forced to live with it.

But that measurement could have been caused by a collision and could have been corrected but overlooked during repair. I should measure mine. It is a good example of a car that has been driven hard. It has been hit on the driver's side. I'll measure and let you know.

[yannis-supras]

If the car was damaged when it was new or near new there would have been every effort spent to make the car as perfect as possible. Deformity could be caused by age and torque but that is such an isolated location. If it doesn't bother you and isn't noticeable and doesn't leak then you're forced to live with it.

But that measurement could have been caused by a collision and could have been corrected but overlooked during repair. I should measure mine. It is a good example of a car that has been driven hard. It has been hit on the driver's side. I'll measure and let you know.

That would be great, sample measurements from other mk2s would give me a better idea of possible age deformities. At this stage I won't just overlook this if it's proved to be a past damage. I've got some serious power plans for my mk2 and as I said I want to make it as close to perfect as possible. The bodyshop guy is a friend as well and said that if this is to be proved as an "out of Toyota allowances misallignement" he's willing and he's got the means to bring the windshield frame back to perfect analogy and allignement.

[sarinas_dragons]

From where would you like the measurements or where did you take your measurements?

[yannis-supras]

From where would you like the measurements or where did you take your measurements?

Well Kenny, since all the frame dimensions I measured are spot on, I would only be interested in the one in question really. So if you could measure your windshield diagonals as Toyota states (upper outer edge of metal trim to opposite bottom inside corner of both diagonals respectively) I think we may come to some interesting conclusions. You said that your car was involved in a side impact once right? Let's see how that affected the upper frame.

[sarinas_dragons]

Yeah, mine has an 84 driver's door replacing the stock door. It's 9:00 in the evening here so I'll measure in the morning and get back to you.

[yannis-supras]

Yeah, mine has an 84 driver's door replacing the stock door. It's 9:00 in the evening here so I'll measure in the morning and get back to you.

That's fine, no probs. Really anticipating on your findings.

[ma615mgte]

ahh im too lazy right now to scan and host the Toyota collison repair manual for the MKII right now..

[yannis-supras]

ahh im too lazy right now to scan and host the Toyota collison repair manual for the MKII right now..

Wayne could you just scan the front windshield bit since you mentioned it? It would be a great help to be able and cross reference the factory measurements and even see if Toyota gives any margins of deviation at all.

[ma615mgte]

can do if i can get this scanner to cooperate

[yannis-supras]

can do if i can get this scanner to cooperate
You could always use a very helping sledgehammer... :ugly_08: :D

[sarinas_dragons]

Yeah, I don't have the body manual and I'd like to. It's nice to have books4cars.com local. I can stop in like it's the library if I want.

Here's pictures of where I measured.
http://i17.photobucket.com/albums/b91/askkenny/Jam049.jpg
http://i17.photobucket.com/albums/b91/askkenny/Jam048.jpg

I measured both sides. The tape measure isn't that clear but it reads 1414mm from upper right to lower left and 1415mm from upper left to lower right.

From where does the manual take these measurements?

[Superium]

Why dont you just get a carfax report? If that kinda extensive bodywork was done Im sure it would of been acknowledged.

[CJSREDPRA]

If the accident repair took place within the last 10 years AND if the car was still possibly in the US, then it might show up in the Carfax report.

If the accident & repairs all took place in Greece (where the car is now), then I'm almost betting that it won't show up on Carfax.... All depends on the car's history timeline.

[yannis-supras]

Kenny the measurements I took were from where you indicate on your second picture (outer upper corner) down to the inner edge of the opposite bottom corner. The thing is that on your car there's only a 0.1mm deviation. That's nothing to worry about really compared to my car's 3mm.
As Chris underlined correctly, me and obviously my car are in Greece. I wouldn't even know what carfax is for this matter. I'd guess that it's some kind of authority that registers car accidents/repairs in the u.s. The car I'm restoring is a u.k. car I bought a few months ago in order to use it as donor car for my mk2.
Basically you people take is as a given that this is an accident repair issue then? This is what I'm trying to find out first of all. There are no signs of repairs on the car (pillars, roof, rear quarter panel) to justify such a serious damage/repair. As I said before there's no other dimensional deviation anywhere else on the car. Isn't there any chance at all that this was a production flaw that may have "escaped" the production line? I'm not trying to intentionally avoid the accident option here, I only want to get to the bottom of this without getting hasty. If there were any other signs leading to a previous major repair this wouldn't have been so weird... :confused:

[sarinas_dragons]

I have reason to reassure you. The dimension difference about which you worry is not worth it. If as you say all other measurements check out and there are no appearance issues it may very well be production tolerance. Maybe Great Britain has CARFAX. Some company reports vehicle registrations, major damage or change, ownership changes and you get to pay a fee to look at the file.

[yannis-supras]

I have reason to reassure you. The dimension difference about which you worry is not worth it. If as you say all other measurements check out and there are no appearance issues it may very well be production tolerance. Maybe Great Britain has CARFAX. Some company reports vehicle registrations, major damage or change, ownership changes and you get to pay a fee to look at the file.

Kenny I'm just about to make a decision and go ahead and repair this. Do you really believe that 3mm is not worth it? To me 3mm seems like a big deviation that would have a great effect with side winds on higher speeds. If it was 1mm like in your car maybe I would ignore it but that's a whole 3mm. From what I understand Toyota gives zero tolerances on the body/frame dimensions. I haven't seen anywhere in the TSRM to give a range of values for one dimension, just one exact value. That's what worries me most.

[sarinas_dragons]

I think what is most important is what you know about the car. You understand that there is a meaurement difference that cannot be detected by the eye or seat of the pants. That and the fact that you went through all the trouble to inform yourself makes your awareness high. I think that you could take the two measurement and reduce it to a percentage, in your case: 3/1114.

This represents .2% tolerance or less than one percent or virtually zero. I restate what I previously said, there is no percentage that you can see or feel and you should be encouraged by that. Put your powers of observation to use on the rest of the car. My car needs alot of work and I hope to enjoy it. Hope you enjoy fixing your car.

[yannis-supras]

I think what is most important is what you know about the car. You understand that there is a meaurement difference that cannot be detected by the eye or seat of the pants. That and the fact that you went through all the trouble to inform yourself makes your awareness high. I think that you could take the two measurement and reduce it to a percentage, in your case: 3/1114.

This represents .2% tolerance or less than one percent or virtually zero. I restate what I previously said, there is no percentage that you can see or feel and you should be encouraged by that. Put your powers of observation to use on the rest of the car. My car needs alot of work and I hope to enjoy it. Hope you enjoy fixing your car.

So Kenny you suggest I should ovelook this? I mean this is going to stay at the back of my mind and I'll always have second thoughts about it. Everytime I'd do some fast cruising and the weather turns a bit windy I'd be really precarious.

[sarinas_dragons]

Yes, If it was my project I could live with it. You will experience nothing but the desire to slow down if you get a MK II to any speed that little difference in body dimension would generate. Really, it won't matter and no one can tell.

[yannis-supras]

Yes, If it was my project I could live with it. You will experience nothing but the desire to slow down if you get a MK II to any speed that little difference in body dimension would generate. Really, it won't matter and no one can tell.

I think I will follow your advice on this one. I'm thinking that I may end up causing more damage trying to rectify this small dimension deviation that has no effect anywhere else on the car really.
I intend in reinforcing the body of the car since its all stripped down. Any particular suggestions on certain areas that would benefit from welding reinforcement?

[sarinas_dragons]

Good for you. I've read what your intentions for the car are. My idea is that there are cars that handle and cars that go fast and cars that do both. If your goal is close to 500 hp then you can't do enough. Seam welding, strut brace and rear brace and bolt in rollcage won't help make up for any mistake at boosted powers so I think you'll have to think hard about these.

I was just reading on www.toymods.org.au. A man on that forum has an old Supra racecar. N/A 300+ hp, nice. I wondered about what his car prep is like but if it was down to 2800 lbs would put the car in the low 12's in the quartermile and the lighter weight taking full benefit of the chassis. That's what I'd want and I'd give up everything weight-wise to get it. What about you, what are your goals?

[sarinas_dragons]

Good for you. I've read what your intentions for the car. My idea is that there are cars that handle and cars that go fast and cars that do both. If your goal is close to 500 hp then you can't do enough. Seam welding, strut brace and rear brace and bolt in rollcage won't help make up for any mistake at boosted powers so I think you'll have to think hard about these.

I was just reading on www.toymods.org.au. A man on that forum has an old Supra racecar. N/A 300+ hp, nice. I wondered about what his car prep is like but if it was down to 2800 lbs would put the car in the low 12's in the quartermile and the lighter weight taking full benefit of the chassis. That's what I'd want and I'd give up everything weight-wise to get it. What about you, what are your goals?

[yannis-supras]

Good for you. I've read what your intentions for the car are. My idea is that there are cars that handle and cars that go fast and cars that do both. If your goal is close to 500 hp then you can't do enough. Seam welding, strut brace and rear brace and bolt in rollcage won't help make up for any mistake at boosted powers so I think you'll have to think hard about these.

I was just reading on www.toymods.org.au. A man on that forum has an old Supra racecar. N/A 300+ hp, nice. I wondered about what his car prep is like but if it was down to 2800 lbs would put the car in the low 12's in the quartermile and the lighter weight taking full benefit of the chassis. That's what I'd want and I'd give up everything weight-wise to get it. What about you, what are your goals?

Well what I'm after really is a balance between a fast car that handles and a street car that's driveable. Meaning I don't really want my supra with a roll cage, for ultimate race use. Well no race use at all for that matter to be honest. I want the car to handle its power nicely on the bends, being able to play with it and yet control it and on the other hand a car that you can still cruise in and enjoy long drives and be able to achieve high speeds securely. I thought of seam welding but I believe that if I go crazy on it I'll turn my car to a brick - no energy absorption - and end up with a very harsh ride and a very unforgiving setup ride wise.
So I will only seam weld the front and rear turrets and inside the cabin along the sides of the car. These are the areas that I know will benefit most. If there are other areas that require reinforcement I would appreciate if you or any one else that is aware off to hint them out for me.
Strut bars front and rear go without saying and on another thread I was also investigating the option of reinforcing the rear frame of the car. I believe suspension wise that the car is going to be set up the best way possible with the suspension mods I'll do. It's the body itself that I want to bring to par.

[sarinas_dragons]

Three years ago I bought a book from books4cars.com. It was a compilation of Toyota sports and GT cars that Road & Track magazine had tested over the years. They started with the 2000GT and progressed through the Celicas and Supras and MR2s.

What was clear was the love for the MKII. Yamaha assembled the engines and they are detuned compared to their motorcycles. Lotus designed the suspension for its qualities. I don't presume to know more than them but I've done alot of study to put me on the same page. Since the Supra's inception there are alot of technical advancements but the math for performance remains the same.

Before I was given my current car I was into lightweight cars. I've figured out what the weight and dimensions of cars have to do with the suspension mount pick-up points. Supras are well designed and take little to get the most from them. It's too bad that racing requires such secrecy. These cars were raced and the engineers never told what they did to optimize the race cars.

But if I understand you correctly you want road balance. That's probably not going to be too hard to get. The one area of performance I've never heard mentioned that could stand better development is the transmission. I think it is possible to improve all the ratios with stock Toyota parts to upgrade to a true close-ratio transmission. The effect of this on the overall car's performance hasn't been discussed on this forum. But I think what I'm getting at is start refining your choices and just keep that attitude. With a close-ratio trans and a taller rear end ratio and I think the car would come alive. My reason for saying this is that no matter what gear you were in the engine would be kept in its powerband. I used a 600 rpm gear split as my target. The drawback would be taller gearing off the line but I'd live with that for close ratios.

I'm having a time finding all the right parts necessary to do the engine changes I want to do but I'm not in any hurry. I'll take whatever time developing what's necessary because there is enough support for these cars. So in the future there will be even better parts so don't sink a bunch into stuff right now. Save it until the potential has been unveiled and work on your car control. I've had track time and nothing takes its place. It also made me drive more responsibly on the road.

There's quite a few competitors on this forum. See if they'll share what they can get out of the parts available now and what they think they need to develope further refinement. I bet most have spent thousands already and still need more. But anything that makes it lighter, gives more flexibility in settings and adjustments, and reduces unsprung weight is where you should concentrate.

[yannis-supras]

Three years ago I bought a book from books4cars.com. It was a compilation of Toyota sports and GT cars that Road & Track magazine had tested over the years. They started with the 2000GT and progressed through the Celicas and Supras and MR2s.

What was clear was the love for the MKII. Yamaha assembled the engines and they are detuned compared to their motorcycles. Lotus designed the suspension for its qualities. I don't presume to know more than them but I've done alot of study to put me on the same page. Since the Supra's inception there are alot of technical advancements but the math for performance remains the same.

Before I was given my current car I was into lightweight cars. I've figured out what the weight and dimensions of cars have to do with the suspension mount pick-up points. Supras are well designed and take little to get the most from them. It's too bad that racing requires such secrecy. These cars were raced and the engineers never told what they did to optimize the race cars.

But if I understand you correctly you want road balance. That's probably not going to be too hard to get. The one area of performance I've never heard mentioned that could stand better developement is the transmission. I think it is possible to improve all the ratios with stock Toyota parts to upgrade to a true close-ratio transmission. The effect of this on the overall car's performance hasn't been discussed on this forum. But I think what I'm getting at is start refining your choices and just keep that attitude. With a close-ratio trans and a taller rear end ratio and I think the car would come alive. My reason for saying this is that no matter what gear you were in the engine would be kept in its powerband. I used a 600 rpm gear split as my target. The drawback would be taller gearing off the line but I'd live with that for close ratios.

I'm having a time finding all the right parts necessary to do the engine changes I want to do but I'm not in any hurry. I'll take whatever time developing what's necessary because there is enough support for these cars. So in the future there will be even better parts so don't sink a bunch into stuff right now. Save it until the potential has been unveiled and work on your car control. I've had track time and nothing takes its place. It also made me drive more responsibly on the road.

There's quite a few competitors on this forum. See if they'll share what they can get out of the parts available now and what they think they need to develope further refinement. I bet most have spent thousands already and still need more. But anything that makes it lighter, gives more flexibility in settings and adjustments, and reduces unsprung weight is where you should concentrate.


Yeap you got me correct there, road balance is my ultimate goal - not flat out race track performance. Based on what you said transmission wise I think I'm half way there. I got a long ratio ring'n'pinion (3.42) for my trutrac but I didn't know that you can alter gear ratios in our gearboxes - I'm using a R154 by the way. But having closer ratios wouldn't it affect top speed? I mean I believe that our cars are great to high speed cruise in and with some decent power under the hood I'd like to be able to hit 160-170mph, even more...

Suspension wise I think all my money has been well spent by now. I don't think there is going to be any revelations in the suspension department that would be applicable to our cars in the near future. I've got a custom coilover setup, whiteline roll bars, T3 adjustable camber plates, strut bars, poly bushes and I'm waiting for Bbaacchhyyss's rear camber adjustment mod from australia. Also ideally I want to get conical progressive springs for my coilovers so I can achieve my perfect balance between comfort and performance. If I cover the latter two I think I'm pretty much set suspension wise. I don't think there's much left to do with it to be honest.

Unsprung weight is going to be a downside though, because with the big brakes I'll fit to the car plus the large wheels, weight is going to be increased I'm afraid.

[sarinas_dragons]

I have looked into the w5x's only. Suspension-wise there have been refinements. Years ago a forum member had an idea ahead of its time. was it you, Ray Fong?

I'd love to implement them but I'm still at the measurement phase. But who wouldn't want even tire contact patches that camber compensation gives? Even if camber compensating component packaging prevents widespread use, Supras haven't even entered the spherical bearing, tubular suspension arm replacements that even first generation Mustangs enjoy.

I love the look of stock wheels on Supras. I just don't think I could bring myself to add weight for looks if I can have both. I've talked to a friend with a machine shop about cutting the lips off a set of stock 14's and use as the centers for three-piece modular wheels that look stock. I think I'd stop at 15x9 fronts and 15x10 rears. But it's worth it to me to be able to make incremental tuning choices so I'd want to try different rim halves to get it right. In the US there are alot of manufacturers willing to do this for the money.

[Junkie]

Guys,for tranny ratios,look into the truck trannies. :p 84-89 or so trucks are where the 3.07 "g-code rear",3.42,3.58 "f-code rear,for our cars :p " come from.I don't know all the trans ratios,but best guess,and having a 87 2wd truck,that's where you need the gears,or just the whole trans from.
4 cyl trucks all had w-series trans,v-6 had r-series.Have actualy had a truck trans in an un-named supra "not mine or Ophirs",and the gearing def. seemed a bit closer.My beater truck,runs out of gear fairly quick,guess I should look at the rear ratio.
Just tossing out some thoughts.

[sarinas_dragons]

Nice, Shawn. All your experience is paying off. Cracked the code. What I did was raise the first gear ratio to the tallest, Then look for the next ratio that is within 6-700 rpm and worked up from there to the lowest fifth gear. On paper it looks awesome. I have a list of the right ones and the transmissions from which to pull them. Now let's make your N/A dragcar the first one to wear one.

My friend that is a foreign stock racer wanted this information for his 3SG/W58 irs car for next year. This year a friend built a 3SG/T10 solid axle car and my friend thinks his car next year will spank everything. His car uses the Van bellhousing with a slight modification to the bore that shares the starter mount. Only 2mm and it fits perfectly.

I forgot to add my friend's car is going to use a MKII third member and axles in double a-arm on all four corners, in a custom chassis, finished weight car and driver just over 1800lbs.