How to lower a P6 - Nick Dunning has it sorted !!

Rumblin_Ron

New Member
Hi guys

Nick Dunning has put a usefull article on tuning the P6 in the General Quieres thread that is well worth a look. Amongst other things he's worked out how to lower the front !!! :O :laugh:
 
Rumblin_Ron said:
Hi guys

Nick Dunning has put a usefull article on tuning the P6 in the General Quieres thread that is well worth a look. Amongst other things he's worked out how to lower the front !!! :O :laugh:
My Goodness!
It's not me!
I couldn't work out how to lower anything...it's an excellent article from a gent in New Zealand. I take no credit whatsoever!

Cheers
Nick
 
Apologies, and very gentlmanly of you Nick.

An industrious chap called Simon Craig wrote the article, but I will give Nick the credit of bringing it to our attention.
 
Simon has quite a few neat ideas.

I like my camber mod better than his. For mine you simply insert suitably hard washers between the pivot arm mating face and the bracket until you can just still get all the thread registered on the nut. That's about 10mm and gives about 1 degree negative.

You’d have to know a really good welder to shorten and reweld the front suspension push rod and then do some pretty aggressive NDT. But it is the simplest and most obvious way of lowering the front - and in engineering that ususlly means it's the best too!

I’m surprised he seems to have kept reasonable handling balance with the huge anti roll bar he has on the front! Note Alan Ramsbottom has uprated Rover type anti roll bars from stock and can do a rear anti roll bar as well. The combination of these and springs of various uprates should allow any handling balance you want between full understeer and full oversteer to be achieved. Personally I loath lowering cars - might look good, but you pay a very heavy price in jittery handling on anything other than billiard table smooth tarmac (and when was the last time you saw any of that not on a race track?)

I thought his lightening attempts were a little feeble. If it was me my first ports of call would be thinwall glassfibre wings and replace the door shells with something else, eg glassfibre copies (Stand up Richard Taylor!). Abandoning power steering and heater is OK for a racer but, in my view, not acceptable for a road car. You could also do something to help lower the roll centre by using a lightweight roof panel
(BMW use carbon fibre roofs on current M saloons and coupes). Ought to be able to get lightweight, ie thinner, glass for the side windows these days as well. Its easy cos they are flat.

I really liked the idea of moving the battery forward of the axle line. I'll case the joint under the back seats next time we have a car up on the ramps. Fuel tank into the boot well is also quite sensible. On mine the same effect is achieved with a 65 ltr gas tank in this position and running the petrol tank 1/4 full.

He quotes 205/50 X 15 as equivalent tyre diameter to standard. That's not correct - it's 205/65 X 15. He wouldn't have had to chop the rear arches about if he'd used the correct offset wheels. That's ET53. For a racer I'd find a different way of achieving that offset than using SD1 Vitesse wheels as the start point. They are very heavy! Obvious solution would be to have a chat with the guys at minilite.

I always thought the 2200's used a four bolt diff like the V8? Whatever he's achieved a really low geraed car by the time he's got the low ratio diff and the undersize tyres together. Again, fine for racing but I'd stick to standard size tyres and the V8 diff ratio for the road. I'm surprised he didn't investigate the LSD options for a racer. Again, Alan Ramsbottom has an off the shelf solution.

I'd humbly suggest the reason he was cooking the greenstuff front pads might be that he was using them with plain discs. Greenstuff pads gas more than normal pads and like to have a grooved disc to allow the vapours to escape. If that didn't do the trick then Alan does a neat spacer mod to the standard front calipers to allow them to grip onto vented discs. Several variants of replacement rear discs as well up to Sierra Cosworth calipers around vented discs (banish rear caliper overhauls for ever into the bargain).

Chris
 
Did he really say "...in case I ever sell the car..."? There are some crazy people out there... anyway, thanks for digging that one out Nick.
 
Sorry to the mods for raising an old thread, but in light of my lowriders thread I found this quite informative...only problem is where Simon states he shortened the control-arm to lower the car 50mm he didn't say by how much he shortened it. Can't find him here as a member to ask, so can anyone tell me if 50mm shortening would equate to 50mm drop or is there a ratio involved?
 
Chris, you are right the 2200 diff is the V8 four pinion centre and the Crown wheel is thicker. You can tell the difference only because the 2200 Crown has two roughly machined grooves on the side while the V8 only has one (or the other way round i forget which) I've done the conversion using a new ring and pinion and it totally transforms the three speed auto. especially around town. I did some posts at the time. There are TWO types of V8 crown wheel, one has the smaller bolts and two special set bolts the later one has all larger bolts. The manual gives details.
 
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