180 degree crankshafts for Rover

180 degree crankshafts for Rover

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Discussion

deleteall

Original Poster:

19 posts

266 months

Sunday 23rd February 2003
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Does anyone know a source for 180 degree/flat crankshafts for the rover 3.5? I'd even settle for a used one. Thanks.

kevinday

12,253 posts

287 months

Monday 24th February 2003
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Errm, why???

350matt

3,766 posts

286 months

Monday 24th February 2003
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To turn it into a flat plane V8 with the associated benefits of a stronger crank, better exhaust tuning, better intake tuning.
There are custom crank suppliers out there, who are remarkably cheap , something like 30/ inch of crank

Matt

boosted ls1

21,198 posts

267 months

Monday 24th February 2003
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Do you want to mail me off line with an idea of your specs. Any advice that I may be able to offer would be unconditional. Billet can be done but are immensly heavy, I had one a while back. It put me right off billet cranks for the Rover v8. I can do SG nodular castings with 2.500" mains and long nose aka cross-bolt engines. Usual stroke is 90mm but I can vary it a bit either side. Engineering books say it's impossible to properly balance a flat plane v8 crank but people do still use them so maybe you would only notice the vibration at low rpm, I don't know?

Mr2Mike

20,143 posts

262 months

Tuesday 25th February 2003
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Putting a flat plane crank into a Rover V8 is bordering on heresy IMO

Not only do flat plane V8's sounds pants, the Rover engine is so limited by the cylinder head that I can't imagine the huge cost would justify any slight power gains. Obviously you'd need a new custom made cam to go with this, and if you you are using EFI, some considerable changes to cope with the changed firing angles.

The Lotus V8 was plagued by vibration problems that caused various essential fastners to unscrew themselves and cause huge amounts of damage.

kevinday

12,253 posts

287 months

Wednesday 26th February 2003
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Thanks Mr2Mike you put my earlier thoughts into words

lawrence1

133 posts

282 months

Wednesday 5th March 2003
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Flat plane crank?? Hmm not worth the trouble unless you've got a hobby of spending money! And as for the extra power, that too is debateable. The crank is only a lever wheather it is flat or twisted. Yes the inherant vibration means you will have to do some serious dampening on that one as well.
Oh and dont forget you will have to get someone to grind you up a special camshaft to suit. The standard one will put you in 'bent valve land'!

So whats a better idea?? Throw out that boat anchor and put in a Toyota 4 cam V8 !!!!!!!

Mr2Mike

20,143 posts

262 months

Wednesday 5th March 2003
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lawrence1 said: Flat plane crank?? Hmm not worth the trouble unless you've got a hobby of spending money! And as for the extra power, that too is debateable. The crank is only a lever wheather it is flat or twisted


The *potential* extra power comes from the exhaust timing on a flat plane V8 which allows you to use tuned length exhaust manifolds more effectively. The really dopey thing about the Esprit V8 is that they stuck a turbo (or two) on it, pretty much negating the only possible benefit the flat plane crank could have given.

jamieheasman

823 posts

291 months

Tuesday 11th March 2003
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Hasn't this already been done by Repco/Brabham or someone? Didn't they do this for an F1/F5000/Indycar type installation in the late '60s early '70s?

Boosted LS1

21,198 posts

267 months

Tuesday 11th March 2003
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I haven't used one but people after loads of rpm seem to want to use them. I can say that although I have seen the billet Rv8 flat plane cranks I don't know a single person that has actually used one. Rovercraft seemed to be into it on their 4.5 turbo engine and I think Ray Webb may have played about with one. I don't need one myself but would like to see one evaluated/tested.

skid

652 posts

264 months

Wednesday 12th March 2003
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Apparently McLaren started using one in their F1 car about 2 or 3 seasons ago. Sounded truley off beat yet very purposefull.

Thing is I've always meant to look into a FP crank but never got round to it. Why is it different to a normal crank. I thought cranks had multiple construction variations for firing orders etc as seen in the 'big bang theory' used on F1 bikes recently.

I understand all that, so how is a FP crank different?

Sorry to be a numpty.

Mark

Mr2Mike

20,143 posts

262 months

Wednesday 12th March 2003
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skid

652 posts

264 months

Thursday 13th March 2003
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Coooooooooooooooooooooool!!!!

I can bore everyone for hours in the pub now. :-)

Cheers.

Mark