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Old 12-16-2010, 03:17 AM   #2731
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Originally Posted by wingracer View Post
I don't know about his modded ones but a stock flash has a higher exhaust timing than any other stock motor I've seen. That would be where the top end comes from. Me, I like how the modded 35+21 spanks the flash all over the place from 20k to about 34k. I bet that even with the top end advantage on the Flash that the 35+21 still has more area under the curve.

Which reminds me, I have been wanting to know if it's possible to put into your dyno program a way to actually calculate the area under the curve? I think that would be a VERY useful number to know when doing comparisons.
Normal NR engines have an exhaust height of 7mm
JP R09 engines I have seen can have 7, 7.2 and 7.5mm
The 2009 standard Flash had something of 7.4mm
The 2009 Flash tuned has.......tadaaaaa...... 8.2mm!!!!!!!! (and the cranktiming was only shifted 1 degree compared to the stock).

But NR is going to higher exhaust ports, also the N21-5T has an exhaust height of 7.4mm
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Old 12-18-2010, 07:06 AM   #2732
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After looking at the chart posted, I to cant see a reason to use a flash, unless the new ones are different.

I have looked at countless dyno charts(big cars) for real cars over the last 6 years and the power band on the 35+21 is outstanding vs the flash. Most of the time the car is going to be using that mid rang around the track.

Grinder do you think the new flash motors match the 35+21's mid range?

Also can you tell us what pipe and header was used for the dyno pulls on those motors?

Thanks for all the info
Hi. Both tests were done using the 2015 with short conical header. The new flash special is more powerful than the old one. Especially midrange, but not as much as the 35+21.

It also depends on which batch you get. For the past year or so the flash, and 35+21 have been coming with the same crankshaft. Sometimes Novarossi decides to put cranks with a longer crank window, sometimes a shorter one. This is true for the flash, and 35+21. You never know what you will get.

Not the timing, but length from front to back. Some of the cranks match the blocks perfectly, and some have a large portion of the crank blocking the flow below the carb. The ones that match are much better.

This makes more work for me if they don't properly match.
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Old 12-18-2010, 07:13 AM   #2733
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got a ? when the window is shorter from front to back does that give u more bottom end
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Old 12-18-2010, 07:25 AM   #2734
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another ? when u modify the knagaroo r u doing the mod for more bottom end or mid or top and when u do modify it does it tanke away from the bottom end.... thanks
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Old 12-18-2010, 07:34 AM   #2735
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got a ? when the window is shorter from front to back does that give u more bottom end
Not in the way they have done it. I almost think it was to use old stock, or a try to make better runtime. The ones with the matched window run harder.
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Old 12-18-2010, 07:43 AM   #2736
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Not in the way they have done it. I almost think it was to use old stock, or a try to make better runtime. The ones with the matched window run harder.
Here is a picture of what I am talking about. The back of the port window is the same, it is the front of the crank that is blocking the flow on the one on the right. Timings are the same.

These were both out of Flash Special engines from a few weeks back.
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Old 12-18-2010, 07:47 AM   #2737
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another ? when u modify the knagaroo r u doing the mod for more bottom end or mid or top and when u do modify it does it tanke away from the bottom end.... thanks
I try to get more top end out of the Kangaroo. It has plenty on bottom, and mid. The mods do not take away bottom end, they only add power in the upper rpm range. It does drink slightly more fuel after the mods though.
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Old 12-18-2010, 08:30 AM   #2738
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so the one with the bigger window gives u more top end? or just more of everything overall?

also on a track that has a short stright and mostly infeild have u every tried a toro nero team ed i here the low end kills the kangaroo could this be used as a poibilty
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Old 12-19-2010, 08:29 AM   #2739
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so the one with the bigger window gives u more top end? or just more of everything overall?

also on a track that has a short stright and mostly infeild have u every tried a toro nero team ed i here the low end kills the kangaroo could this be used as a poibilty
The larger window gives the engine more of everything. I have not tried the Toro in an on road car. I will have to give one a go.
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Old 12-19-2010, 08:01 PM   #2740
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Old 12-19-2010, 10:27 PM   #2741
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Originally Posted by Grinder View Post
Here is a picture of what I am talking about. The back of the port window is the same, it is the front of the crank that is blocking the flow on the one on the right. Timings are the same.

These were both out of Flash Special engines from a few weeks back.
Man, pretty noticeable difference. I can definitely see where that would cause you more work
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Old 12-21-2010, 04:12 AM   #2742
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anybodody here anything about the reds motors by m rossi
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Old 12-21-2010, 11:48 AM   #2743
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Hi Uriah,

Novarossi came out with a new plug, dubbed "C8TGH". Have you had a chance to try it with your engines?
I am still struggeling to find good glow plugs since Nova's quality went south.
Which plugs do you recommend for the MM Kangaroo and 35+21 in typical northern european conditions (From 60F to 85F; 55% humidity).
The OEM Kangaroo comes with a Nova 6 plug. I assume that you recommend a cooler one after your modifications, right?

Thanks a lot and best regards, Stefan
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Old 12-21-2010, 03:51 PM   #2744
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anybodody here anything about the reds motors by m rossi
i believed they were tested in the us to see if they were to impor them
by mugen usa but thats it, you can see it for youself in the hands of
di angelo on his mrx5 in the world in miami, i ve heard the 12 version was
as good as other high end engines
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Old 12-23-2010, 01:03 PM   #2745
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Hey Uriah what is the better buy? What is faster? Murnan rb c10 or Murnan flash?
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