Thick flange or thin flange??

[rocket534]

Looking to find out when the change to the thick flange heat exchangers went into effect.
Just bought some Dansk heat exchangers for my original engine, low mile, 1970 911T. I was sent the thick flange pieces but now I find that the originals were thin flange.
I want to use the right ones [and don't particularly want to pull all the studs and replace them with longer ones to mate with the thick flanges.]
Which ones are correct for the '70 911T?

[toddu]

Thick was '81 I think. Maybe '80?

[Dodge Man]

Is it the 70T motor? Changing the original 40+ year old studs would not be a fun task with the motor in the car. I went thru the SSI part numbers on Pelican to "learn" the differences and got the thin flange with the proper port size for my 83 ROW motor. It worked for me. SSI sells a thin flange for the 70 application. Did you buy the set new or from a PP?

Here on Pelican:

SSI Heat Exchanger Set
(pair), thin flanges, 911 (1966-74)
Brand: Stainless Systems Inc.

Price

SSI Heat Exchanger Set (pair), thin flanges, 911 (1966-74)