Flat plane crank - Cam

oneaves2005 · Post by **oneaves2005** » Thu Jul 25, 2013 1:04 pm

Has anyone had a cam made to go with a flat plane crank in an RV8? If so where from and at what cost.....

unstable load · Post by **unstable load** » Fri Jul 26, 2013 10:27 am

Not had one done myself, but I was rummaging around on the CRANE Cams site and they claim that if you contact them they will do whatever you need for you....

sidecar · Post by **sidecar** » Fri Jul 26, 2013 11:20 am

Do you have a flat plane crank then?

oneaves2005 · Post by **oneaves2005** » Fri Jul 26, 2013 11:30 am

I don't have one yet but will get one made over the winter if all goes well. I just wondered if anyone knows of a cam profile that works and has been tried and tested. I have spoken to piper and they will make one up also but there must be someone who makes them up at the moment as there are enough people running flat plane cranks.

Darkspeed · Post by **Darkspeed** » Fri Jul 26, 2013 5:49 pm

Why bother - just fit the TVR AJP engine.

minorv8 · Post by **minorv8** » Tue Jul 30, 2013 5:27 am

My friend has contacted the usual cam suppliers and the price is around 800 quid mark. He has a 40 mm stroke TVR flat plane crank. Only needs to sort the rods and the cam.

kiwicar · Post by **kiwicar** » Tue Jul 30, 2013 8:04 am

Hi
You are aware of the vibration issues asociated with a flat plane crank?
The AJP is actually probably a simpler and cheeper alternative unless it absolutly must be a rover block.
Best regards
Mike

minorv8 · Post by **minorv8** » Tue Jul 30, 2013 10:11 am

Our stupid legislation makes it more or less impoosible to stuff a V8 into a small car. You can only increase the capacity +25 % over the largest engine within the model range. So, it is tempting to create a 2 litre V8 using a TVR flat plane crank and get a legal V8 equipped car.

Then there are the interpretations, e.g. Sierra model range where you have Cosworths and XR4 models. SA versions like XR8 is not applicable, same for Peranas because our DoT exclusdes any versions from SA or Australia market. 5 litre Sierra would be very nice.

Vibrations would be an issue, would be nice to know of TVR had any tricks with their engine, maybe the supercharger is used as balancing shaft

oneaves2005 · Post by **oneaves2005** » Tue Jul 30, 2013 11:07 am

Indeed, it has to be a rover v8 block, 3.9l + 0.80 and the stroke must be 71.12mm....

Post by **scudderfish** » Tue Jul 30, 2013 5:51 pm

minorv8 wrote:Our stupid legislation makes it more or less impoosible to stuff a V8 into a small car. You can only increase the capacity +25 % over the largest engine within the model range. So, it is tempting to create a 2 litre V8 using a TVR flat plane crank and get a legal V8 equipped car.

Then there are the interpretations, e.g. Sierra model range where you have Cosworths and XR4 models. SA versions like XR8 is not applicable, same for Peranas because our DoT exclusdes any versions from SA or Australia market. 5 litre Sierra would be very nice.

Vibrations would be an issue, would be nice to know of TVR had any tricks with their engine, maybe the supercharger is used as balancing shaft

Where in the world are you?

Regards,
Dave

JP. · Post by **JP.** » Wed Jul 31, 2013 6:02 am

scudderfish wrote:Where in the world are you?
Regards,
Dave

Obvious, Europe. Ive read all his issues in Appendix J & Appendix K.

While I was building my race car a just few years back I was following appendix J which made my car fall in to Group 2. ( Ford had no GP2 homologation for my car)
Finally got the car finished and "J " got replaced by Appendix K and my car falls into nothing. I gave up and made the car road legal.

minorv8 · Post by **minorv8** » Wed Jul 31, 2013 1:45 pm

Finland mate

We are supposed to have a specific approval system where you can get oversize engines approved but you basically need to justify why you want to do that. Racing etc is not accepted. Just for fun or good sounds are lousy excuses as well

kiwicar · Post by **kiwicar** » Wed Jul 31, 2013 2:51 pm

Hi
The AJP has 2 ballancer shafts running at 2X engine speed one on each side of the crank, No tricks it is just the way you have to go to get rid of seconday harmonics.
You can see the sprockets for them in this photo
http://2.bp.blogspot.com/_E5ELxVgPQd4/T ... blog_3.jpg

Why not use a normal 90 degree crank, with the reduces stroke you could use a built up crank motorcycle style, if you did some carefull parts selection and got the weight right down it would be pretty easy to get it fully ballanced and have it rev like mad making up for the lack of capacity. The flat plane aproach sounds simple to start with but when you get into it it is not.
Best regards
Mike

minorv8 · Post by **minorv8** » Wed Jul 31, 2013 5:24 pm

Mike, he already has the crank

Darkspeed · Post by **Darkspeed** » Wed Jul 31, 2013 7:02 pm

minorv8 wrote:Mike, he already has the crank

That's not quite how it reads above - and I have never been aware of any sort of numbers of people running flat plane RV8 motors. Just seems hugely expensive for little point - Unless someone wants to spend some time explaining the reasoning behind it all and why it makes sense.

Sidecar wrote:Do you have a flat plane crank then?

oneaves2005 wrote:I don't have one yet but will get one made over the winter if all goes well. I just wondered if anyone knows of a cam profile that works and has been tried and tested. I have spoken to piper and they will make one up also but there must be someone who makes them up at the moment as there are enough people running flat plane cranks.