View Full Version : Rover fly wheel...

16-07-01, 08:17 PM
Hi Guys,

It's been some months now since my last post, I was talkin' before of which engine I should be looking to put in my Sumo snake - anyway I've decided (With the useful suggestions made by the forum) upon the Rover V8 3.5 - I have aquired such an engine some time ago, from a late SD1. Which I am having rebuilt by a local garage in Devon. The engine is being sent away to be balanced but the original engine had no fly wheel and the only second hand one I've tracked down is one from a range rover, which will fit but I'm sure is heavier than that of a car flywheel...

My question is this, Should I use the flywheel I've aquired, or keep looking for a lighter wheel. or possibly go and buy a new one (Which I'd rather not do as I'm on a tight budget) - does any one have experience of such a setup and would it make a difference? The mechanic who is rebuilding the engine asked me if I was ok with the setup, but I must confess - Car engine mechanics is hardly my forte.

Thanks in advance...

Dan 'Were all these nuts used before?' Man :-)

16-07-01, 10:22 PM
U sure a range rover one fits , i had a range rover engine and put a sd1 on .


17-07-01, 01:16 PM
Get a proper SD1 flywheel from RPI or somewhere - If money is tight, why are you bothering to get the engine balanced ?

17-07-01, 08:17 PM
I don't know if the range rover flywheel will be a straight swap for what your'e trying to do. I'm sure it will fit the engine, but how about the gearbox?

If it's OK why don't you simply have it machined to the weight you want. Bear in mind that your Cobra is 30% lighter than the SD1 you can easily take the flywheel down to 26lbs. Any decent machine shop should be able to do it for you, and as your'e having the engine balanced they could balance the flywheel and clutch at the same time.

You could always try a post to http://www.rover-v8.co.uk/index1.htm and post a question on the forum.

Good luck


18-07-01, 06:44 AM
.........ideally you would want to lighten it as your vehicle is lighter than the Land rover from which it came. Also, the harmonic ballancer at the front of the engine might need to be matched to the flywheel type. Lastly, the flywheel and clutch pressure plate ought to be ballanced with the engine. You will have to get them zero ballanced seperately if you don't get everything done together!


18-07-01, 01:20 PM
As you have pointed out Rigman, I plan on having the Engine and flywheel balanced together - which is why it is important I get the right flywheel. I was mistaken in to believing the engine was from an SD1 - after matching the engine number (17D07493B) against the engine list @ http://www.rover-v8.co.uk/body_data1.htm came out as being the following:

17D00001B Range Rover Classic 3528cc 9.35 125 92 Pulsair LT77 ba

Which may explain why the Range rover flywheel fits (Steve tate's point)

Considering now I am sure both the engine and flywheel are correctly matched, should I consider having it machined to make it lighter? as suggested by Kev... before I get the engine balanced. what are the benefits of having a lighter flywheel?

Dan 'Were all these nuts used before?' Man

18-07-01, 05:33 PM
I`ve had my rover v8 bored and stroked many moons ago by a company called rovercraft,now called progress engineering in Maidstone,Kent.
I opted for forged pistons and carillo racing rods and had the whole caboodle lightened and balanced,and ran it in SD1 on the strip,it now sits Happily in an AK waiting to be used in anger.
i am reliably informed a lighter flywheel enables engine to rev quicker thru` the gears and improves midrange torque,the downside,(there always is one)is engine looses pace on long uphill climbs and you need to change down thru gears,as i never encountered any long hill climbs on the strip it never became an issue,and i doubt if it will in a car as light as cobra replica`s

Mal, with half built AK!}> }> }>

18-07-01, 05:51 PM
Thanks for your comment mel - it makes alot of sense, would any one know of a garage in S/W London area that can machine the fly wheel to make it lighter. I spose I could give those friendly people and real steel a call.

Any pointers glady received.

Dan 'Were all these nuts used before?' Man

18-07-01, 08:19 PM
Err... I really wouldn't do that if I were you ...

Lightening flywheels is a job for the specialist - especially considering the amount of cracked SD1 flywheels that are kicking around. Yep, I'm sure any old garage that does machining will offer to take a few lbs off your flywheel, but if done incorrectly (ie. taking metal from the wrong place or not carefully balancing afterwards) could seriously weaken the structure. The last thing you want , if you value your feet, is for the flywheel to 'give up' when your pulling 6000 rpm with your new balanced 3.5.

If you must go this way, go to someone like Dave Ellis ( 024 7635 2888 ) and buy one of his brand new flywheels which are manufactured to be quite a bit lighter than standard.

Personally, I'd spend my money on other types of tuning before touching the flywheel !


18-07-01, 10:20 PM
If you go to a reputable machine shop with a used flywheel, preferably an SD1, it can be refaced and made to look like new, not necessarily with the intention of lightening it. I had mine done and it came back with a pattern on it similar to engine turning. Not too much metal can be taken off though, so if it's too worn it'd be better to scrap it. Tip: Take out the clutch pressure plate locating dowels yourself. I left mine in and the cost of removal was more than the machining. Can't remember the price of the dowels but they are cheap and are pressed in the holes. The whole job was 45 inc VAT.


19-07-01, 09:48 AM
..........that's why I bought a shatter proof McLeod bellhousing, if you see where your legs/knees are in relation to the flywheel and what is in between you and them on a Cobra with a regulay ally bellhousing, then you might think again! At the end of the day, like other performance items, it's all about peace of mind. Mind you, there is nothing 'performance' about a shatter proof belhousing, it weighs a ton!


19-07-01, 12:36 PM
Rigman, Where did you get your bellhousing from? I've still to aquire myself an LT77 Gearbox.. Don't spose you have any lying around, buddy. don't spose you fancy stripping down your lovely car to help a poor builder out ;-)

Dan 'Were all these nuts used before?' Man

19-07-01, 01:05 PM
Thanks for the number, It's gone in to my black book for future reference :-) . If I'm putting my engine at risk of breaking through bad craftsmanship - I think I'll stick with the standard flywheel even if it is heavier than required. I'll just have to save weight by removing the passanger seat }>

Dan 'Were all these nuts used before?' Man

19-07-01, 02:18 PM
'Fraid not Dan, you'll have to get your own! Antway, give the boys at RealSteel a ring, they can fit you out with whatever you need. Get hold of their catalogue at least, it was a vital source of info for me when I built mine!


21-07-01, 10:29 PM
The Range Rover Flywheel is about twice as thick and heavy as on the SD1.
The Range Rover clutch is also bigger than on the SD1. I think the RR is around 10.5" and the SD1 about 9.5". The assembly won't fit inside the standard SD1 bell housing. I suppose it would be possible to have the flywheel
re-drilled to match the smaller SD1 clutch but I'm still not sure the bell housing will fit.
I was in a similar position to yourself in that I took my engine out of a RR. I bought a second hand SD1 flywheel but decided not to fit this as it had tiny cracks in it. In the end I went to RPI who didn't have any SD1 flywheels in stock but have machined down a RR one for me. This is actually lighter than the SD1 flywheel which I still have.
I can't tell you how the engine runs as i've not fitted it yet.

Good luck

27-07-01, 06:45 PM
My flywheel is at 22lbs and i had to have it balanced externaly
For every 1 lb u take of the flywheel the engine reacts like u have taken
10 lbs off the car!! so my car is 100lbs lighter (in theory)
This only has an effect under load.
You do loose out hill climbing but the car is so light anyway i
really don't see that it matters.
It does make a big difference to acceleration!!!!
My engine revvs so much better!!:D

28-07-01, 09:45 PM
Depends on where you take the material from & gear ratios...

Go too far and you'll sacrifice that wonderful low-rev big V8 quality whereby you can cruise smoothly in 5th at almost tic-over revs !