Jag IRS into chassis

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SirrahBRA
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Joined: Sun Sep 05, 2021 6:17 pm

Jag IRS into chassis

Post by SirrahBRA »

Hello,

Does anyone have a good picture of how the Jag IRS ties into a hawk chassis.

I have a BRA with a jag rear end that was done a long time ago, I think I need to improve how it is attached to the chassis.

The car came with letters from BRA dated 1988 suggesting using a jag IRS is not a good idea.

thanks
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clive
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Re: Jag IRS into chassis

Post by clive »

Hi,

Are these any good?

Image

Image

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Cheers, Clive.

(If I'm not here I'm in my workshop or on the golf course!)
SirrahBRA
Posts: 28
Joined: Sun Sep 05, 2021 6:17 pm

Re: Jag IRS into chassis

Post by SirrahBRA »

clive wrote: Sun Sep 19, 2021 9:32 am Hi,

Are these any good?
Perfect thanks. Makes me feel a bit better about mine, mine is only attached at the rear to the lower mounts, where as this is attached at the front only. I was planning to also attach mine at the front so should be fine with just that.
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peterc
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Re: Jag IRS into chassis

Post by peterc »

I assume you also have a bracket that picks up the four bolts on the top of the diff casing. In the case of the Hawk that bracket is held at both the top front onto the chassis and underneath to take the shock of the spring loads.
Additionally a heavy piece of angle also takes some of the vertical load from the front pivots by being bolted up underneath the chassis. So its only the rear pivot points that are not supported.
Working from a pit I was able to slacken off all the bolts to shim the assembly without fear of the car dropping. I have since discovered I should have been shimming each part of the assembly. e.g. driveshafts for camber and pivots for toe in.
Peter C
SirrahBRA
Posts: 28
Joined: Sun Sep 05, 2021 6:17 pm

Re: Jag IRS into chassis

Post by SirrahBRA »

peterc wrote: Sun Sep 19, 2021 12:15 pm I assume you also have a bracket that picks up the four bolts on the top of the diff casing. In the case of the Hawk that bracket is held at both the top front onto the chassis and underneath to take the shock of the spring loads.
Additionally a heavy piece of angle also takes some of the vertical load from the front pivots by being bolted up underneath the chassis. So its only the rear pivot points that are not supported.
Working from a pit I was able to slacken off all the bolts to shim the assembly without fear of the car dropping. I have since discovered I should have been shimming each part of the assembly. e.g. driveshafts for camber and pivots for toe in.
Peter C
Yes the four bolts at the top are picked up, then the rear lower bolts are picked up by a separate frame the runs down behind. I will add a load path to the front lower pick up direct to the chassis.
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