"you can also use a glass grinder to accomplish the same effect." Care to elaborate? Use 964 glass but trim it down and use the 964 seal?

Philip take a look at my last post and the edit. I don't think glass grinding is the way you want to go. Looks to me like my last shop did that just to get the 964 glass in...but it was never done right. (it left gaps on the edges and it leaked) Window is out right now redoing it. So far it has been a bbbeeeeeeeaach with one broken windshield to date trying to use the 964 glass and seal.

I'll know more in a couple of days.

Thanks again. Looking forward to the final results.

We tried to grind one down ONCE! We put it in and all was good.
Till we came in the next day and it was BROKE!

So I think the bottom line here is USE the right seal an windshield.
It will save you a Lot of $$$ and all the BS that goes with it.

We won't even try it any more. Especially when a 964 windshield cost over $900 bucks and I can't afford eating any more.

GooD Luck Guys your gona need it. ;)
SmileWavy

Hmmmm,

I've wanted to do this to my 78 Turbo, and was actually headed down that path within the next 2 weeks... until I ran across this thread.

Have seen earlier cars with the 964 seal front and rear....no idea which glass was used.

Had a friend that did this to a 77 Turbo, he even changed to 964 doors as this provides a different side seal as well.

The Porsche part number for these seals are listed as fitting 87 thru 94

OK, It looks like there is no combination that will work - unless somebody starts making custom seals...

Where did all those old posts about putting a 964 windshield/seal into an earlier car come from anyway?

re 1 db & etc. ...
Phil - you might be able to make something that would blend the gap at top into the roof line. I don't think it would be pretty -- something like the bulbous look of a 964 bumper but on the top windshield/roof seam...

Don't be too quick on that opinion Randy. 964 seals do work in older (pre 74) cars with the original size windshield. My shop has done many of them. Just not every car every time. Still haven't tried that combo (older, smaller size windshield and 964 seal) in my car but will this week.

Rdane..

Just want to clearly understand..

So 964 seal... which windshield?

Lettuce understand that the problem is not which seal or which windshield, it's which seal and which windshield into which car. Gets complicated.

True - I was referring back to the original post... or what I dimly remember to be the original post.

Here's a whataa I'ma gonna do:

My stock 89 (assuming it hasn't been replaced) windshield with the internal antenna will come out for paint. I'll have my guy order the 964 seal and try it. If it doesn't fit, I'll go with the stock seal. Any tricks for getting this combo to fit, if it will fit?

I looked into this conversion a little. The flange on the 911 and 964 are actually different, I believe the 964 being 15mm and the earlier 911 10mm wide. Another interesting fact I was told that non factory PPG replacement glass seems to only come in one size for both body types now, not the two sizes that Porsche shows.

i have a 74 with ppg glass no trim . the seal is made to use trim but it looks like a no trim seal when used with ppg glass no gap the seal looks good

I just got my w/s replaced in the 87'. Stock glass with a 964 seal. Just drove to Cali and back, no issues and no leaks. The installer used a rope and had it installed in 1 hour.

I got my car back today after some issues with a 964 windshield and 964 trim.

Maybe this will help someone else thinking about the conversion.

First off my car is a '79 coupe. Targas are another story all together I am told.

When we did the major body work conversion one of the things I had done was replace the standard windshield with a 964 windshield with a antenna inside the window. That was a couple of years ago and I was rushing to get the car done after months in the shop. I now remember that I had also wanted to go with a 964 seal and there were some "issues" that I didn't investigate further at the time. I should have.

Got the car back with a 964 window in the car but the original '79 seal and trim. Turns out it was never done correctly and the installer ground the corners of the winshield to get the 964 glass to work with the original '79 seal. Window leaked and worse yet it was never very stable in the frame. Lucky I didn't loose the glass out of the car in normal driving let alone on the track. I never realized just how bad it was.

Talking with one the more reputable local shops who has done the 964 seal conversion on many earlier (pre '74) race cars I thought it time to refit the seal and attempt to fill the typical gaps between seal and A pillar on the driver's side that cause water leaks.

I had leaks in heavy rain but wasn't really sure where they were coming from...wind screen seal wasn't the first suspect. But thought it worth looking at.

Porsche has 3 different parts numbers for earlier wind screens er but those are normally a tint/color option and then there are two diffent wind screens by seal size. As Ryce commented on, the window opening is the same but "around" (can be before or after, no rime or reason on this one) 10/3/1988 the pinch weld lip inside the window went from 10mm to 15mm. That changes the windshield and the seal required. Best thing to do is measure your pinch weld.

Windows are suppose to be the same size but most window guys will disagree with that point as well with the 964 window being a bit larger the pre'88 a bit smaller.

Monty tried every combination of windshield (7) and seal (2 styles) and a dozen different seals for manufacturing variations. The only thing that actually fit my car correctly was a '79 windshield and a '79 seal with metal trim. (no big surprize :)

We ended up using a FM amp under the dash for the radio as I never us AM anyway. Also Monty was able to move the glass around and center it in the window with no gaps on the upper corners of the A pillar where a previous installer had used dum-dum or 7mm rope.

Mine is not the easiest car to work because it seems to be at max spec in the windshield frame...but the job came out perfect.
I have to thank Monty at Redmond European for putting the time and effort to make it better than right...it is actually perfect.

As you can see in this thread some have been successful in the conversion some have not. Best thing to do if you have a glass guy willing to try is give it a shot. But my caution is, if they don't succeed fairly easily the first try I wouldn't force it. My guess is you'll be happier by just going back to your original style window and seal.

Good luck as it is a cool conversion!

Now what about the back window?

Sounds like 964 glass and 964 seal won't work well in the '84 to '87 Carrera series, right?

Now that I am at the point of making the measurements in order to trim my Lexan windshield to fit into a 964 seal and be installed in an '83 SC, it looks to me like the Lexan needs to be about 5/16" larger than the stock 911 glass all the way around. Maybe slightly less, but that's a considerable difference in glass size in any case. I'm going to cut it to 5/16" larger so that I can sand it down further if that's too big, but I'll post my end results.

From my limited experience I believe that to be correct.

RDane,

Thanks for taking the time to post this data.

I'll have my 89 930 measured, but

"As Ryce commented on, the window opening is the same but "around" (can be before or after, no rime or reason on this one) 10/3/1988 the pinch weld lip inside the window went from 10mm to 15mm. That changes the windshield and the seal required. Best thing to do is measure your pinch weld. "

Since I haven't looked into this, is it the general consensus that the 15 mm pinch weld lip allows the 964 seal?

According to Porsche yes, 15mm will take the 964 seal and window. Suppose to start at serial # 91KS12059 in the coupe and serial # 93KS060072 in the Turbo coupe but you still need to measure.