3 Or 3A - Difference / Does It Matter?

[Guest RoborRoss]

Hi Again,

 

I'd like to quote an old post (I really should have done my research before buying!) and ask a few questions.

 

Whats the difference between 3 & 3a and how to tell?

The items in the quote below, are there any pics to assist with identifying the problems / preventing them?

Any meets in the Derbyshire area anytime soon? I've a barrel full of questions!

 

Thanks in advance!

 

 

All monocoque Hoods will crack in certain places over time. The mark 3 / 3A, will crack at each corner of the engine bay, the front corners first, the crack will appear in the vertical weld in the corners and travel across the top fold of the chassis if not caught quick enough.

 

Where the front suspension top arms pivot, 2mm plate just isn't sturdy enough to take the punishment, this will wear then crack.

 

Where the front shockers clamp to the chassis at the bottom, (in front of the rad) another weak point.

 

now go to the rear:..........................

 

The rear shockers mount to a piece of angle iron that it bolted to the top of the chassis fold. After time, the angle iron will bend, and tear out of the chassis. The whole thing neads strengthening.

 

The other thing is, if you still have the Zimmerframe RH shocks fitted, throw them away ASAP and fit something better.

 

Depending on how you've mounted the fuel tank, hanging it by straps/long bolts/threaded bar from the boot floor, as in the RH instructions, will in timebend your boot floor nicely!

 

 

Each and every one of these faults, I've had to overcome and sort out. I've also seen them in many other monocoque cars, along with other problems that are relevant to that model.

 

Exmo's; Top front shocker mounting.

 

Mark 1 sierra (or S7 as a lot of people want to call it) has a fabricated assembly that contains the front suspension bolted to the front of the monocoque tub, this in turn can pull and crack the tub where the stresses are most.

[Snapperpaul]

Never quite worked that out myself, believe the 3a had certain mods to assist SVA for instance the front bumper.

My 3 had one in the kit to bolt on later, the 3a (I believe) had one ready mounted to the tub

There may be other differences

[brumster]

Ah yes, I think you may be right there, the 3A had a prominent tube under the front nosecone didn't it?

[Big Jim]

There was very little difference with the mark 3 and the 3A. Basically the 3A was the same kit, but with all the "extras" included, ie. it had a set of escort clocks that you needed to "modify", I think there was a set of alloys as well. Mine is a mark 3 and it had the bumper, yet I know of a 3A that didn't have the front bumper. A lot depended on what RS decided to include in the kits at the time.

[Snapperpaul]

My kit did not have alloys but did have independant guages, water temp, oil pressure, fuel gauge and a 50mm rev counter but no speedo.

[Snapperpaul]

And the there was the "New 3"

[Guest RoborRoss]

So I guess there is no way of telling for sure then? What about the mods required to resolve the issues in the quote? Are these documented anywhere?

 

Thanks

Rob

[Snapperpaul]

I haven't seen cracks in mine but do check

There is an extensive list of mods for IVA mainly the seatbelt mounts and height.

Other mods are for durability, rear shock mounts, diff mount, seat mounts.

Worth doing is the tie bar mod replacing the Sierra front antiroll bar

[Guest mower man]

PM me if you want tie bar mods ,I need your postal address to send ,mower man[mick[