330GT 2+2 Bodyshell Rebuild

[cory]

Just a thought. When I did the floors, front box and outriggers it was important that the outriggers and front boxes were done first. The outriggers tie into (weld) to the very inner sills. This gives you the alignment for the floor height and alas the seat positioning. The bottom floors are actually pieces, with four unequal sides folding downwards, that fit up into the cavity created by the outriggers, longitudinal main frame, and inner sills.
The front jacking points actually go thru the foremost frame box that you will be building. The rear jacking points go thru all three sill sections and are welded in front of the front leaf spring attachment point. Those locations can be seen in the pictures I posted.
Again, imo, building and placing those outriggers and front boxes are crucial to insure the correct alignment and placement of the pedal box and correct exaust height/placement. Fabricating the floors are the easiest, and funnest, in the process. Thank you and good luck.

Correction to my statement on the rear jacking points. They do go thru all three sill sections however they are welded to an "ear" protruding from the frame section that has the forward leaf spring attaching point and the bottom stabilizing arm attaching point. It is the tube seen in the photo showing the leaf spring and lower stabizing arm.

[Darren C]

Thanks again Cory,
The front jack tubes were still in my car, so I cut and replaced the steel around them for the inner sill (you can see one in my picture on the first post on this thread) The rears were completely missing, so I made these like the front and welded them into all three steel sections that make up the sill (rocker panel) I have them protruding about an inch under where the floor goes. Great information on the "ear" bracket, I'll make some up and attach them as you suggest.
With new metal in my sills I have had the car stood on 4 x home made stands that fit in the jack holes with no issues so there is plenty of strength in the area now.
Thanks again.

[Darren C]

Whilst repairing my 330 bodyshell and rebuilding the chassis, I have taken literally hundreds of measurements used string and even a laser line to get the chassis pretty much millimetre perfect. The shell has been causing me no end of trouble. Over the last year I have been walking around car shows and garages with a plumb line, rule and notebook in my pocket on the off chance of finding another 330 parked up to measure. My quandary is that having set my chassis straight and true I find that when the body is mounted on the centreline true to the chassis the wheel arches are not in line. Both on distance between front and rear, and height from floor to the 12 o’clock point of the arch, and the overhang of the wheels. The shell is all over the place!

So I set about measuring other cars to see what is correct. Like most things with old classics I think I have uncovered another can of worms.
ALL the cars I measured were different.
NO single car had the same measurement on each side regarding how far the wheel sat in the arch?
I checked each car had 3801 wheels, and measured from the rim edge so that tyre differences would not matter.
My car’s shell is showing a 10 to 12mm difference from the Left side to the Right side with regards to how far the wheel sits back in the arch.
The worst car I measured had a 30mm difference between left and right. Generally I found the front wheels to have a greater difference, but one car I measured was over 25mm difference on the rear?

So my question is….

What is NORMAL for a 330?

I can’t believe that all the cars I measured had twisted chassis’s or badly fitted replacement wings, but there seems to be a pattern that the Left side wheels sit deeper into the arches than the Right side. Equally I can’t believe that this is how the cars left the factory?

Has anyone else experienced this? What measurements do your cars have?

Here’s how I’m measuring. Start with the car on level ground with equal tyre pressures if possible.

1. Hold a plumb line (cotton thread with a weight on the end, an old nut will do) against the wheel arch at 12 o clock point on the arch top.
2. Steady any swinging, then hold a rule against the very edge bead of the wheel and measure between line and wheel.
3. Compare left and right for front & rear wheels

I’d be interested to see if your cars follow the theory that the Left side wheels sit deeper under the arch and what the general average measurements are for a Series 1 & 2.

Example

Front Measurements



Rear Measurements




Thanks in advance

[cory]

Just a few thoughts to add. Ferrari's operating, maintenance, and service handbook for the 275,330GT, and GTC show the front wheel camber dimension to have a tolerance of 6.35mm to 9.52mm. Within the front end components are a number of bushings and wear points in the kingpins, spring cups, upper and lower control arms, etc. The rear wheel measurement you speak of can also be affected by no less than 4 bushings within the leaf springs and shackles, and 4 more on the stablizing arms, per side. This doesnt take into account the shocks. And after all that now we would get into the body work and lack there of that could throw off those measurements.
I would be willing to bet that each car measured would all be in some form of disrepair regarding all these wear points thus giving different measurements from car to car. As a side note all bushings and wear points on my car were changed. Front and rear shocks rebuilt by Koni. With apx 40 miles on the car the left side rear wheel sits inside the wheel well, ever so slightly, deeper than the right side.

[tyang]

The discrepancy seems normal for these hand made cars up into the 70s. Restoration shops and metal fabricators are always struggling with how much to correct on a car that came asymmetrical from the factory!

Tom

[Darren C]

Tom, Cory,
Thanks, that certainly makes sense. I think the real question I am trying to understand is what’s the accepted tolerance.
I do not want to chase the impossible dream on getting the car mm perfect when that’s not how it should be. I understand entirely about the suspension set up, bushes and wear, but let me throw another variable into the pot.
If I stick my head under the front and rear wheel arches and measure from the vertical tube bracket holding the bumpstop at the front and the bump stop bracket at the rear, to the edge of the wheel arches at the 12 o clock position I get differing measurements eitherside of the car.
This confirms my theory that the wings and rear quarters are fitted un-evenly to the shell, which throw them out of alignment to the chassis. So I need to understand whether 12mm is an acceptable “factory” tolerance from left to right regardless of any wear, shims or settings of the suspension. Otherwise it means that new panels must have been badly fitted at some time in the cars history.
The measurement I took on one “sample“ car I came across on the rear is a little worrying since the rear axle is fixed so a 30mm difference left to right would in my opinion be excessive. The 12mm difference I have on my car from chassis to wheel arch is in my mind excessive, but I have nothing to compare that with since I did not get chance to measure from chassis or bump stop to arch on each car I saw at a show. (I got plenty of funny looks as it was with measuring from arch to wheel rim!)
To confirm, my new chassis was set mm perfect centreline of my shell on an imaginary line running front to back. To explain if I measure from the dead centre of windscreen opening, rear window opening, bonnet (hood), door openings and boot openings, they line up dead centre of my chassis, yet the car seems wider on the LH side than the RH side by 12mm.
So, what is the accepted tolerance in the Ferrari community?

[cory]

Tom, Cory,
Thanks, that certainly makes sense. I think the real question I am trying to understand is what’s the accepted tolerance.
I do not want to chase the impossible dream on getting the car mm perfect when that’s not how it should be. I understand entirely about the suspension set up, bushes and wear, but let me throw another variable into the pot.
If I stick my head under the front and rear wheel arches and measure from the vertical tube bracket holding the bumpstop at the front and the bump stop bracket at the rear, to the edge of the wheel arches at the 12 o clock position I get differing measurements eitherside of the car.
This confirms my theory that the wings and rear quarters are fitted un-evenly to the shell, which throw them out of alignment to the chassis. So I need to understand whether 12mm is an acceptable “factory” tolerance from left to right regardless of any wear, shims or settings of the suspension. Otherwise it means that new panels must have been badly fitted at some time in the cars history.
The measurement I took on one “sample“ car I came across on the rear is a little worrying since the rear axle is fixed so a 30mm difference left to right would in my opinion be excessive. The 12mm difference I have on my car from chassis to wheel arch is in my mind excessive, but I have nothing to compare that with since I did not get chance to measure from chassis or bump stop to arch on each car I saw at a show. (I got plenty of funny looks as it was with measuring from arch to wheel rim!)
To confirm, my new chassis was set mm perfect centreline of my shell on an imaginary line running front to back. To explain if I measure from the dead centre of windscreen opening, rear window opening, bonnet (hood), door openings and boot openings, they line up dead centre of my chassis, yet the car seems wider on the LH side than the RH side by 12mm.
So, what is the accepted tolerance in the Ferrari community?

I havent followed the whole story with your purchase however I do remember seeing that the body was removed from its chassis. With that being said I believe that it wouldnt take much to get that body, less chassis, out of being dead nuts on and or wider on one side by less than 1/2" from simply moving it around. No matter how much cross bracing was installed. Some unknowns, how long it had been removed and how many times was it moved around a shop/yard before it finally was supported and or landed in your hands. As Tom touched on these cars were far from being perfect from the factory and or the coachbuilder.

[Darren C]

Hi Cory,

Yes the bodyshell had sagged and I have pushed and pulled it in all directions to get it back into shape. But what I'm asking isn't about my car.
I'm trying to understand what the original factory tolerances were to see what is and isnt acceptable. Once I know that I can push and pull my car back into shape.
I have heard many stories of how good and bad the alignment and tolerances were, but no one has ever said its + or - 1/2" or + or - 1/4" for example.
I would like to know by measuring as many cars as possible what the average is. Since the 330 panels were pressed there should be some consistancy on this, but so far I've measured 8 cars and all are different worst 30mm best 5mm difference left to right.
In measuring my shell I can say for certain the tubular frames under the front wings are even from side to side in relation to the centre of the car. It's the pressed steel wings and quarters that seem to be out ?

[tim]

Greetings… Hows bout putting together a list of measures that would help you and we can submit the measures from our cars.
I remember a friend who had won at Pebble Beach in the 60's showing me a head on shot of his 250 GT Europa. The windshield sloped one way and the grill the opposite. He said thats they way they were built.
Morgans still vary a lot from car to car and often by an inch or more.

Tim

[Darren C]

Thanks Tim,

Thats what I was kinda hoping for. But not just to help me. To help everyone in future with some sort of reference data. This would be much better than anecdotal and urban myths.
It could start with the measurements I showed in the two photo's and build to much more over time.
A local restorers to me have a full car laser scanner that they put rare race cars in to scan the whole body, so that if it ever got damaged in future it could be repaired with accuracy. This would be fantastic but costly to do for us mere mortals, but a few measurements of individuals cars would build some sort of data base that could only be beneficial to all of us.

[cory]

Measuring wheel arch to closest portion of side wall with plumb bob distance was as follows: Front driver side: 5.85mm
Rear driver side: 6.05mm
Front Passenger side: 4.75mm
Rear Passenger side: 5.15mm

[Lowell]

Measuring wheel arch to closest portion of side wall with plumb bob distance was as follows: Front driver side: 5.85mm
Rear driver side: 6.05mm
Front Passenger side: 4.75mm
Rear Passenger side: 5.15mm

I just measured the difference of the driver's and passenger's side front gap with a plumb bob as shown in the photo. Driver's was about 2.0 mm shorter than passenger's.

[Darren C]

Thanks Guy's

2mm is a very good tolerance compared to the cars I've measured, but also confirms the theory that the shells are wider on one side????

It would be interesting to see what more cars are like.

[Darren C]

Ok, the next biggest and confusing result I have found is the arch profile height on the front.
This makes the car look as if its riding higher or lower from side to side, when the car is sat level and true.
Take a straight edge (softwood etc) that won’t mark the paintwork and lay it across the top of the front wings at the centre point (12 o clock) of the wheel arch and measure down from the underside of the straight edge to the top or highest part of the wheel arch. Then compare sides.
I have measured cars over an inch difference? This is not due to the suspension or any twist in the shell, it appears to be where the arch ended up being pressed in the wing.
Arch height


If the photo appears cropped on the RH side just click on it to show the full image as I’m not sure how to get it to fit on this forum. thanks

[Darren C]

On the straight edge across the top of the wings measuring down to 12 o clock on my wheel arches I get 175mm RH side and 184mm LH side, 9mm or 3/8” difference side to side.
This is replicated when I measure vertically from the seam at the base of the wings to the opening for the wing vent. One side is 10” dead, the other is 10 3/8”????

This is bizarre as when you look behind the wing there is no visible repair, its one complete pressed panel, which would suggest the pressing is 3/8” different in height between LH & RH side as even if you mis-aligned it when fitting, these two measurements would still be the same?

LH side



RH side



The more I measure the more I find the tolerance on my car is around ½” give or take which is enormous.
Again if I measure horizontally along the top of my sill (rocker) at the seam shown in the picture above, I get 71 ¾” on the RH side and 72 ¼” on the LH side from arch to arch.

These particular measurements cannot be due to twist in the shell, only differences in the panel pressings unless anyone else has any ideas?