Hexagon Classics 411

peter dowdle · #1 (**permalink**) 07-09-19, 10:54 PM

Hexagon Classics Have A 411 For Sale Apparently With A Gm Turbo Hydromatic 4 Speed Auto Box. The Car Also Has An Unusual Fuel System Which Might Be Gas Or Injection. Does Anyone Know The History Of This Car . I Believe Fitting A Chrysler 4 Speed Box Is A Big Job Maybe The Gm Box Might Be Easier?

Kevin H · #2 (**permalink**) 08-09-19, 12:36 PM

Here's a link to the car at Hexagon;
https://www.hexagonclassics.com/car/...s-4--1974-3591

In addition to the GM transmissions, it has clearly also had a few modifications in the cabin trim. As for the fuel system, it looks like it might be either an LPG or dual fuel set up.

Kevin H · #3 (**permalink**) 08-09-19, 10:43 PM

If it has a 4 speed GM transmission, it only has D,2 & 1 forward gears on the gear shift. Strange.

peter dowdle · #4 (**permalink**) 09-09-19, 08:44 AM

Kevin did you notice why the clock had been moved?

To fit the LPG gauge in the main dash.

There is the answer to the fuel issue

Kevin H · #5 (**permalink**) 09-09-19, 08:08 PM

Well spotted Peter, I didn't notice that (only that I didn't like what they had done with the clock!)

Given that they could have retained the original fuel pump, maybe that's tell-tale sign that it is dual fuel. I did notice that the void beneath the petrol tank is no longer visible in the boot, so that is presumably where the LPG tank is. There's also an extra bit of carpet attached in the left hand side of the rear wall of the boot; presumably that is hiding the LPG connector.

I think this is something they should mention in the listing.

I wonder if it really has a 4 speed GM transmission?

Philip · #6 (**permalink**) 09-09-19, 09:50 PM

Yes, it’s not the only one with a GM 4-speed.

Kevin H · #7 (**permalink**) 09-09-19, 10:56 PM

Quote:

Originally Posted by Philip

Yes, it’s not the only one with a GM 4-speed.

It's weird that they used the same gear shift which only allows selection of 1,2 & D. I suppose it doesn't matter too much because most people would leave in D anyway.

Does that mean the selectable gears are really 2,3 & D with the GM transmission?

Was this GM transmission an original factory fitment?

Kevin H · #8 (**permalink**) 10-09-19, 05:18 AM

Quote:

Originally Posted by Kevin H

Given that they could have retained the original fuel pump, maybe that's tell-tale sign that it is dual fuel."

Sorry, not sure how I ended up typing that! I meant to say "they could have replaced the original fuel gauge" (with the LPG gauge).

Philip · #9 (**permalink**) 10-09-19, 08:46 PM

Quote:

Originally Posted by Kevin H

It's weird that they used the same gear shift which only allows selection of 1,2 & D. I suppose it doesn't matter too much because most people would leave in D anyway.

Does that mean the selectable gears are really 2,3 & D with the GM transmission?

Was this GM transmission an original factory fitment?

The four-speed conversions using the original style of gear shift that I’ve seen just use the original 1,2 & D; it isn’t a factory fitment.

Barrie · #10 (**permalink**) 20-09-19, 08:58 PM

I think original 1,2,D arrangement in the cockpit is retained for ease, simplicity, and cost saving.
The engineering involved in changing is too experimental/costly.
Personally I have never seen it done.

However there is a way around it with this device:
https://www.hgmelectronics.com/compu...sport-and-pro/

I have an earlier less sophisticated version of this on my Chrysler 518 transmission.
It enables you to alter change-up speeds and, if you have one, alter at what speed the torque converter lock-up engages. Also lots of other features that I have not been able to investigate yet.