New member with a few Rovers, mainly P6b

[gelmonkey]

Hi Joakim
Thanks for the info.
Mate has 16"wheels on at the moment and is just not happy with them.
Wants to go slightly wider but is not sure about offsets etc and as you know the pcd is 127mm and not too many styles to choose from.
He has found some out in the USA but still not sure that he wants to commit to a purchase that may still not be right for him.
Have told him the info he needs but can understand his dilema up to a point.

Cheers
Paul

[Swede]

Glad if I can help, I think the car is ok on the road with Astrovan/Rallyewheel offset but if I add the extra 1,5 - 2 inches inwards it will be more like Rover engineers intended it and that must count for something...I will keep running fairly narrow tires though...195´s at the most...

[sowen]

On my p6 I've chopped away part of the d-post area, and re-profiled the rear doors and wings to fit modified 15x8 chevy truck steels with 225/50/15 tyres.







I've also fitted a jaguar powerlock into the relatively stock rear axle/suspension, only shortening the rear driveshafts by 1.25 inches each side and fitting a custom two piece propshaft.

The caddy v8 looks nice and snug in the bay, good luck with the projects

[Swede]

Hello Sowen, I am an occational visitor to your build thread over at Retro Rides and i am impressed with how you solve the technical issues as well as the quality of your work. I too have serious thoughts about switching to a jag diff in due time...a rod building friend of mine has aV12 unit on stock with LSD and another mate has one that is probably off a 2,8...both units are missing brake caliper parts so I am thinking about converting to SAAB 900 Calipers as they are easy to find around here (reconditioned) and they have a good solution for the handbrake. Is your car up and running at the moment?
Regds/Joakim

[Swede]

Here is another solution to the rear wheel well problem.....I have never been in touch with this guy though...
http://www.garaget.org/?car=56463&image=1154148

[Swede]

These were the small GM pattern 4 3/4 ", so I opened them up to 5" which means they now fit both...same old issue with offset though...they will have 2" added to the rear before I will put them on the car....they will go on the four speed car as on the picture but 7" wide instead of 5"

[Swede]

...so...if i was to install the M112 on the 7 litre engine and rev no more than 3800-4000 i can rev the M112 3 revs/engine rev without overstressing it...
3X14,7X1835=80923,5...this is then divided with half the volume of the engine....80923,5 / 3500=23,121.....from this amount i deduct 14,7....and end up with 8,421 PSI...this is what would be if i did not loose any PSI in the process (cam overlap and other leaks)...am i right or am i rambling?

(Found the info on planet soarer, great stuff!
14,7 is the pressure of the air surrounding us and 1835 is the amount of air the M112 delivers/rev)
//Joakim

[kiwicar]

Hi Joakim
Basically sound but you are assuming a Volumeric efficiency of 100% at those revs, depending on the duration of the cam and how good the heads are I would think you will be running closer to a VE of about 70 to 75%, you may get a bit higher. I would run it about 2.3 to 2.5 engine revs are you going to intercool it? I think it would be a very good idea. If so give it a few more revs and boost.
Best regards
Mike

[Swede]

...I will have a lot of fabrication ahead of me before I can install the M112 but this makes the whole project much more interresting....70 percent of 8,4 psi = 5,8 psi...I think i will start somwhere just above 2:1 and see what gives...It is my plan to fabricate a new intake manifold in order to further reduce engine weight, i already have huge piece of 1cm aluminium that is perfect for this job, the layout will be the same as Jaguar with discharge upwards from the M112 and then I will have one plenum for each cylinder head. Intercooler is a later option but I will start out without it....did anyone ever consider using an air conditioning unit in a "wet" intercooler?
//Joakim

[kiwicar]

Hi
sorry I was talking about the VE of the engine, ie how much the cylinders fill and there by how much restriction the supercharger will see, you need to lower the drive ratio to compensate ie from 3:1 to 2.3 ish. The efficiency of the supercharger effects the heating of the charge by the supercharger and for a modern design like the m112 should be around 80 to 85 % work on 2.3 to 2.5:1 and it should give you about 8.5 psi boost plus let you rev the engine beyond 3800 a bit when you want say to 4500 ish.
Best regards
Mike

[sowen]

Hello Sowen, I am an occational visitor to your build thread over at Retro Rides and i am impressed with how you solve the technical issues as well as the quality of your work. I too have serious thoughts about switching to a jag diff in due time...a rod building friend of mine has aV12 unit on stock with LSD and another mate has one that is probably off a 2,8...both units are missing brake caliper parts so I am thinking about converting to SAAB 900 Calipers as they are easy to find around here (reconditioned) and they have a good solution for the handbrake. Is your car up and running at the moment?
Regds/Joakim

My car is sat in the garage under blankets right now, unfortunately I haven't really had the time to get on with it and there are lots of little bits I still need to do to it. I do some bits every few weeks but not enough to update my retro rides build thread. The most I seem to do is roll it backwards and forwards so the tyres don't go square.

The p6 in the garaget.org link looks to have a similar amount of metal removed from the d-post as mine for the wider tyres. I really want to convert mine to 2 door, then I can similarly flare the rear arches a bit more for wider tyres on the rear, 245-255 possibly

[Swede]

Hi
sorry I was talking about the VE of the engine, ie how much the cylinders fill and there by how much restriction the supercharger will see, you need to lower the drive ratio to compensate ie from 3:1 to 2.3 ish. The efficiency of the supercharger effects the heating of the charge by the supercharger and for a modern design like the m112 should be around 80 to 85 % work on 2.3 to 2.5:1 and it should give you about 8.5 psi boost plus let you rev the engine beyond 3800 a bit when you want say to 4500 ish.
Best regards
Mike

I am very happy with this information Mike, this makes my random purchases come together for a higher purpose. I will continue working on the project later this winter, as soon as I have the engine mounts finalized I will start working on the pulley arrangement, now i know what size to fabricate.
I am not quite sure about what I will do with the cooling problem yet, the P6b had cooling issues from new and my project is not likely to make this issue go away...
The headlamp arrangement allowes a radiator that is 67 cm wide and thats it, I will look at the new Alu radiators on the market up here that are offered for older US cars, and hope to find one that fills the space well. To put intercooling in front of the radiator or to use the engine cooling system for the same purpose might proove unsatisfactory, this is the main reason for me to start out without it, hoping to find an acceptable torque figure without heading into a very hot blind road. I will strive to keep this car looking as close to standard as possible...no hints except when you read the fine print on the rear decklid...maybe.... Again, thanks for the help with calculating my possibilities.

[DaveEFI]

I've had 2 P6B's - a Mk1 auto and a MkII 3500S, and neither had cooling problems. They do run very hot, though, which can cause fuel vapour lock.
But that's because there's a lot of engine in a confined space.

[kiwicar]

Hi
Cooling should not be too much of an issue, I think you should easily make 350 to 400 bhp but at such low revs that the friction losses will be low and therefore heating of components like wise will be low. The rad out of a 350 chevy or a 302 ford should be more than enough, the one for my chevy was only 24X13X 2.5 inches and that was to take 550 BHP
Your choice of cam may be tricky to get the best out of the combination but even there somthing close to standard but with extra exhaust duration and lift should be ok.
Good luck
Mike

[Swede]

Hello Sowen, I am an occational visitor to your build thread over at Retro Rides and i am impressed with how you solve the technical issues as well as the quality of your work. I too have serious thoughts about switching to a jag diff in due time...a rod building friend of mine has aV12 unit on stock with LSD and another mate has one that is probably off a 2,8...both units are missing brake caliper parts so I am thinking about converting to SAAB 900 Calipers as they are easy to find around here (reconditioned) and they have a good solution for the handbrake. Is your car up and running at the moment?
Regds/Joakim

My car is sat in the garage under blankets right now, unfortunately I haven't really had the time to get on with it and there are lots of little bits I still need to do to it. I do some bits every few weeks but not enough to update my retro rides build thread. The most I seem to do is roll it backwards and forwards so the tyres don't go square.

The p6 in the garaget.org link looks to have a similar amount of metal removed from the d-post as mine for the wider tyres. I really want to convert mine to 2 door, then I can similarly flare the rear arches a bit more for wider tyres on the rear, 245-255 possibly

Same situation here mate, new job is soaking up most of the energy and as of yet does not render the financial power to get things necessary for maintaining build momentum....All is not idle though, I am assembling a 3,5 RV8 with CR 10,5:1 and tuningcamshaft of unknown specification for testing purposes right now...this engine is a recent purchase and has not been used since the BW35 gave up on it more than 15 years ago according to the seller. He also claims it was astonishingly quick for such a small engine so I am very keen on letting it rip. As a testing rig I will use a derelict Volvo 740 GLE, this years project car for our annual 3 hour winter stock car race. always held on the same iced track in a nearby farmfield...mission is to stay out of trouble as much as possible and to clock up as many rounds as possible for the duration.

Here are some pics of last years event.
http://brelleman.se/?p=10&album=2&gallery=54
I ran a stock Volvo 244 painted orange.

If this Rv8 prooves in good mechanical order I will later use it for the manual car, mated to the volvo 4 speed with OD...or put it in the Range rover maybe...undecided...

You should seriously consider the 2 door alternative...will look very nice with the look you are heading for. I pesonally find the chopped P6b Coupe that Graber built the best looking P6 of all times...It should be possible to use sections from BMW 2002 0r 635 for the rear pillar solution as well as for opening rear side windows. the other unchopped cars I have seen do not impress as much though...not sleek enough. Mercedes managed to convert their heavily designed 4 door saloons to the SL models...I wonder what a skilled artist can do with the P6 Saloon if he or she had the same goal...