Steering, Suspension, & Brakes

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waterbucket
Philip Waterman
England
(103 posts)

Registered:
07/30/2011 01:08PM

Main British Car:
1972 MGB GT

MGB front suspension
Posted by: waterbucket
Date: February 21, 2021 03:31PM

Today I have been looking through the front suspension parts that I have accumulated from a 1978 GT parts car plus some other bits that I already had. Some of you may already know that I am intending to fit a Jaguar AJV6 3.0 engine into a 1972 MGB GT, With the engine weighing 100lbs less than the 1800 plus an alloy radiator and bonnet, I have already fitted a triangulated four link rear suspension similar to the CCE one with 185lb springs. I think I need some advice on springs for the front but this also is not quite how it originally was either. I have increased the front track by two inches to match the rear track simply by moving the front pivots out that amount, that on its own has raised the front roll centre to a very stable 23/4" above ground level the shock absorber mounts and upper spring locations have been moved by the same amount.
What I would like to know is what is likely to be the right spring for it, I have an almost new pair of C-AHT21 springs 480 lbs (these are 1 inch lowered for competition or lowering RB to CB height springs) which are the right length or a touch long when fitted, with a 150lbs weight loss at the front end will these be too stiff? I removed from the 1978 GT a pair of springs that I think are from a post 1972 roadster and rated at 372lbs not 348lbs, they do not conform with those on this list [mgaguru.com] The length is the same as BHH1225 but the wire diameter is .520" not .498 or .54" According to my calculations with a likely front end weight of 1000lbs both will give exactly the same ride height, in this case about 1/2" above CB height.
The very last thing is the sway bar, to my astonishment the bar is a tiny fraction under 7/8" Too Big?
Does any one have any ideas other than wait to get it on the road and drive it with all the combinations?


MGBV8
Carl Floyd
Kingsport, TN
(4112 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
1979 MGB, Buick 215

authors avatar
Re: MGB front suspension
Posted by: MGBV8
Date: February 22, 2021 09:45AM

Depends on your driving style, Philip. You will have to install the springs & road test them. Do you want a stiffer ride? Less lean in the corners? If you don't drive hard, the softer spring will be better. A 7/8" sway bar would also likely be too much.

For reference, I went from stock front RB springs, to 480, 550, then 660 springs. Changed the sway bar from the OEM 5/8" to 3/4" to 7/8". Handle great, but many would not be happy with the ride. I wasn't going for the plush Caddy ride. :)



Edited 1 time(s). Last edit at 02/22/2021 10:13AM by MGBV8.


waterbucket
Philip Waterman
England
(103 posts)

Registered:
07/30/2011 01:08PM

Main British Car:
1972 MGB GT

Re: MGB front suspension
Posted by: waterbucket
Date: February 22, 2021 02:51PM

Carl
I think your analysis is about right, I knew that I had the short 480lb springs but the 372lb ones were a total surprise. About twelve years ago I bought a rubber bumper GT shell with both front and rear suspension but no doors, fenders etc and I have used it for trial fits. I had already removed and sold the rear axle which was poly bushed and had stainless braided brake hoses, when I dismantled the front suspension which again was poly bushed I expected to find the same 480lb springs not some lighter ones from a roadster. I had been thinking that the soft springs and stiff sway bar would give a good ride and fairly flat cornering. I also thought with 185lb rear springs that I might end up with excessive understeer with the heavier springs only time will tell. My wife will drive it as much as I will, so that has some bearing on the choice.
I am not sure but I think you have posted about cutting a sway bar in the centre and extending it by sliding a piece of tube over the two ends and welding the tube to the sway bar. I presume that you would plug weld the tube to the bar rather than welding completely around the end of the tube ends.


MGBV8
Carl Floyd
Kingsport, TN
(4112 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
1979 MGB, Buick 215

authors avatar
Re: MGB front suspension
Posted by: MGBV8
Date: February 22, 2021 03:33PM

I have found hat a much stiffer sway bar will also impart some extra ride stiffness.

"I am not sure but I think you have posted about cutting a sway bar in the centre and extending it by sliding a piece of tube over the two ends and welding the tube to the sway bar. I presume that you would plug weld the tube to the bar rather than welding completely around the end of the tube ends."

Welded around the ends plus a couple of plug welds.


Jim Stabe
Jim Stabe
San Diego, Ca
(795 posts)

Registered:
02/28/2009 10:01AM

Main British Car:
1966 MGB Roadster 350 LT1 Chevy

authors avatar
Re: MGB front suspension
Posted by: Jim Stabe
Date: February 23, 2021 02:28AM

Bend a new bar, don't weld up one out of pieces.


MGBV8
Carl Floyd
Kingsport, TN
(4112 posts)

Registered:
10/23/2007 11:32PM

Main British Car:
1979 MGB, Buick 215

authors avatar
Re: MGB front suspension
Posted by: MGBV8
Date: February 23, 2021 09:27AM

Been tried & tested on an MGB & a TR6 road race car, Jim. Not pretty, but does work.


waterbucket
Philip Waterman
England
(103 posts)

Registered:
07/30/2011 01:08PM

Main British Car:
1972 MGB GT

Re: MGB front suspension
Posted by: waterbucket
Date: February 23, 2021 02:39PM

I have only just realised my email address in my profile is one that I stopped using three years ago but I have not been able to change it, any ideas as to how?



ex-tyke
Graham Creswick
Chatham, Ontario, Canada
(1141 posts)

Registered:
10/25/2007 11:17AM

Main British Car:
1976 MGB Ford 302

authors avatar
Re: MGB front suspension
Posted by: ex-tyke
Date: February 24, 2021 08:01AM

Quote:
I have not been able to change it, any ideas as to how?
Click on your profile 'waterbucket'....click on 'My Control Center' on the top bar and then click 'change my profile'


Moderator
Curtis Jacobson
Portland Oregon
(4494 posts)

Registered:
10/12/2007 02:16AM

Main British Car:
71 MGBGT, Buick 215

authors avatar
Re: MGB front suspension
Posted by: Moderator
Date: February 24, 2021 12:12PM

Nope. Email address has to be changed by a moderator. Just send me an email with the necessary details...


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