6.9 power and Rumours

[motec 6.9]

Over the years there has been a lot of claims about modified 6.9's from video with Dan's http://www.youtube.com/watch?v=BxN4AQNzFYE . Which I believe was never completed as owner is in bad health . But no dyno results to verify power. Other cars the same. At this point I believe I am only one to post dyno results which is currently 255.6hp at the rear wheels. Car will be going in for head work in next few weeks. And will fit cams and cam sprockets and 560 throttle will be fitted at the same time. Then Dyno and back to strip. Only car I believe with extreme mods to get dyno is twin turbo in Sydney. If anyone can verify other claims which I have never found proof of please post. I will also take car back to strip after mods to see if I can go under my current 14.24@97.21mph. these items will be fitted when head work done and will post pictures of work. https://www.youtube.com/watch?v=BZ3CbLYAp3s&feature=youtu.be

 

[Oversize]

Seems most were completed on very tight budgets and so no proper verification was ever conducted; sad really. Maybe we can change that.....

 

[motec 6.9]

As said a lot have posted starts but not completed. Owner of 6.9 to drool over has not posted in a while. I intend to verify my mods as I want to prove what does and does not work. I have a set of 278 duration cams to fit with cam sprockets . Heads are being posted as valve guides need repairing. It will be dyno-ed with heads pictured after port and polish.

 

[motec 6.9]

as is known this is most likely the most powerful M-100 6.9 when completed. I have been quoted for the intake manifold should I wish to go aftermarket efi again.

 

[Oversize]

It is a very neat setup.... I can't wait to hear it!

 

[Oversize]

Anyone know if the coupe made it to Summernats??

 

[Oversize]

Geoff did u check WOT vacuum at max RPM on the dyno? If not can you check it on the new engine after running in?
If the engines keep increasing hp with bigger n bigger throttles then it's an obvious restriction. Clearly there's a point where there's no purpose increasing size any further when power becomes limited by other factors such as port size. And a massive single throttle plate can affect drive ability. But I don't think anyone's found that limit yet, so let's keep testing the boundaries...

The reason the engines were 'low' on power for their size is due to their breathing ability which was as intended. MB was compromising between race car, budget & road car. They certainly didn't want lumpy cams with a rough idle and low vacuum. Nor did they want a money pit that was the W100

 

[motec 6.9]

It will be tested as I will be tunning FrankenCIS WUR . And fitting Oxygen sensor to exhaust.

 

[Oversize]

Here's a link to various performance calculators:

http://www.hipermath.com/math_center/racing_calculations

It's very interesting to punch in a few different numbers and see what comes out. Seems the original throttle WAS too small. In fact, with a car intended for some track use and revving to 6K the throttle should be nearly 100mm!

 

[Oversize]

At 5250 RPM redline a road car should have an 80mm throttle and race 92mm.... Clearly a lot bigger than the standard 65mm (or was it 70mm)??

 

[motec 6.9]

It is 65mm Standard Mark

 

[motec 6.9]

I will do dyno on my car when new engine is built. May do it before fitting big throttle and FrankenCIS WUR. Will see.

 

[Oversize]

Now there's an idea! When are they likely to finish? Have they mentioned a run-in procedure?

65mm on a 6.9 litre big block; how completely mad! I think they got scared about how much power the engine would produce and whether the transmission would cope! And probably concerned about how many owners would back them into the bush without traction control!!!!

 

[motec 6.9]

I am thinking of leave standard throttle body and WUR on while running engine in as I know they work and it will work as a restricted governor . As for completion hoping in next few week.