Range Rover P38 RV8 Manual flywheel

[Chassis 33]

Right, who knows about P38 Range Rovers? I'm currently building up a ex-P38 V8, the engine came out of an automatic car but I'm using it in a manual. No problems so far, I can just bolt up one of my existing flywheels to the end of the crank...however what I'd really like to do is keep the 36-1 trigger wheel that is riveted to the back of the flex plate that came with the engine this way I can keep the standard OEM crank sensor that is safely hidden out of harms way, instead of using a trigger wheel amalgamated to the crankshaft pulley. The question is which is going to be easier? Getting a machine shop to drill and tap the back of an existing flywheel to accept the trigger wheel, or find a manual P38 being broken and buy the flywheel, then drill and tap face of the flywheel to accept a 9.5" 2WD clutch?

Answers on a post card to the usual address.

Regards
Iain

[Steve_D]

Messing with the flywheel has the potential to cause balance issues.
A Transit trigger wheel (£16) + an Escort sensor + a fabricated bracket will do the job on the front pulley.

Steve

[Chassis 33]

Dont worry about that, the whole thing will be needing balancing anyway as I'm replacing the flexplate with a flywheel.

Regards
Iain

[Talkwrench]

Its a very easy job for a shop to fit the trigger wheel to your flywheel. Try finding a manual V8 P38! Hens teeth ....

Edited by Talkwrench on Thursday 12th February 19:50

[AntonyJ]

Ian , I have a manual 4wd flywheel here.....

[Chassis 33]

I've got all the kit to do a crank pulley mounthed trigger wheel, wouldn't need to worry about machining as the alternator is going to be on a custom bracket and thats the only pulley I'll be needing driven.

I have three concerns using that set up though, firstly it looks a bit Heath Robinson, angled bracket here, toothed ring bolted on, solitary bundle of wires coming forward (presently the engine electrics would finish at the forward pair of injectors and it looks very neat), secondly with not running any inner wheel arches the sensor will be rather exposed and protecting it will only add to the Heath Robinson look and thirdly the sensor fouls where I want to hide the alternator...

...sooooo I want to try and utilise the OEM setup as much as possible because it looks fit for purpose in that I can utilise all OEM sensors wiring etc that I already have, its well protected and gives me plenty of room to fit my alternator, in short so long as I dont need to re-write the laws of physics I'll be running a flywheel mounted setup.

Antony, you'll very shortly have an email!

Regards
Iain

[eliot]

I feel that this one I done is reasonbly tidy for a front mount:
http://www.mez.co.uk/dcam/DSCF1125.JPG

Clearly the OEM position would be better - perhaps some photos may help us.

[Chassis 33]

Right, as requested time for some pics...
Thanks to Antony I've now got 5 variants of RV8 flywheel, well 4 and a flexplate if you want to be pedantic, knocking about.

Clockwise from top we have a P38 vintage flexplate with trigger wheel, traditional 4WD flywheel, standard 2WD lightened and with a groove machined for the trigger wheel, and finally a standard 2WD flywheel. I also have a lightened traditional 4WD flywheel thats been drilled to accept a 240mm clutch.

Some close ups in the same order








And here you can see the relative thickness of the 4 flywheels

Top to bottom, the two 2WD flywheels first the one with the groove, then the standard, the lightened and faced 4WD flywheel and an original 4WD flywheel.

Regards
Iain

Edited by Chassis 33 on Sunday 15th February 12:51

[eliot]

So whats the problem then ? - you have flywheel with a trigger wheel in it (the 6 oclock one)

[rev-erend]

More importantly - what do they weigh ?

I think mine was about 18 lbs.

[Boosted LS1]

Rangie flywheels are heavy as fook due to the extra thickness and larger clutch pcd. You could use an sd1 flywheel and still fit a large diameter clutch if you're on a budget. I fitted a mcleod twin plate onto a rover flywheel and they handle huge horsepower/torque. A single plate would also fit. An sd1 flywheel is a lot thinner/lighter, or maybe go alloy and use an insert. Helix make some very nice stuff and it's not that expensive given that it'll be pukka for the job.

[Chassis 33]

eliot said:

So whats the problem then ? - you have flywheel with a trigger wheel in it (the 6 oclock one)

I didn't, but thanks to Antony I do now

rev-erend said:

More importantly - what do they weigh ?

I think mine was about 18 lbs.

I've weighed them in the last day or so...
4x4 30lbs
lightened 4x4 22lbs
standard ex Chim 2wd 26lbs
lightened 2wd with trigger groove 17lbs
flexplate 15lbs.
More telling than that will be the weight removed from furthest extremities of the flywheel, I=m.r^2 and all that
Regards
Iain

[2woody]

irrespective, I'd avoid the P38 manual flywheel, as they're all "dual-mass", and will all be fooked.

put it this way, a P38 flywheel will only have been removed for one reason !

[rev-erend]

Can someone please explain how dual mass flywheels differ from normal .. all I've ever heard is that they seem to wear out after a few years service.

[Boosted LS1]

^ It could be because there is the first section with the ring gear and then another large section to accept the clutch which is large o/d but I'm only guessing. It's almost like 2 flywheels in 1

[rev-erend]

I found this 3d amination of a dual mass flywheel

http://www.youtube.com/watch?v=YnaXB8q3uzQ

It's use seems to be more for NVH issues .. diesels in particular.

[That Daddy]

rev-erend said:

I found this 3d amination of a dual mass flywheel

http://www.youtube.com/watch?v=YnaXB8q3uzQ

It's use seems to be more for NVH issues .. diesels in particular.

nothing but trouble i hate em

[rev-erend]

That Daddy said:

rev-erend said:

I found this 3d amination of a dual mass flywheel

http://www.youtube.com/watch?v=YnaXB8q3uzQ

It's use seems to be more for NVH issues .. diesels in particular.

nothing but trouble i hate em

Yes - it seems like a conspiracy..

Car's getting ultra reliable .. but we need to keep the garage trade busy .. so lets add more consumables.

Dual mass flywheel replaced solid flywheel
Centre push clutch replaced side mounted slave cylinder
Cam belt replaced cam chain

all require extensive labour to fix and non really seem necessary .. was not broken.

Don't fix it.

[GreenV8S]

rev-erend said:

all require extensive labour to fix and non really seem necessary .. was not broken.

Don't fix it.

Cheaper to make, I guess? Except the flywheel, that's obviously going to cost more but is seen to work better.

[russell_ram]

"I'd avoid the P38 manual flywheel, as they're all "dual-mass","

Only on the Diesels. V8 manual flywheel (4.0L only from the factory) were standard solid type.

Russ