New Novarossi 91 DD

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RonShaw

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Apr 13, 2011
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Well, the new 91 Novarossi DD is in its final stages of testing. Thanks to Jerry Crowther, Martin Truex, and a couple of others for helping with testing over the past few months to help us get to this stage of the process. Novarossi World has worked diligently over the past few months to incorporate the changes and advice from our testing group. I am pleased to introduce the Novarossi 91 Direct Drive, with a picture below of the engine incorporating the latest changes. Some hydro racers may run little or no cooling through the secondary case cooling ring, but to help keep temps ranges where they need to be, some cooling for hydros through this ring may be required, and for restricted air cooling such as with monos and offshore with hatches, full cooling through this ring will be imperative. As with any race engine, proper cooling monitoring during break-in and during testing and open water to achieve proper running and racing cooling temps will be imperative. Proper heating/cooling is just as important as a proper needle to not only save your engine from early extensive wear, but will also guarantee the consistancy needed to put you in the winners circle.

I wanted to extend the final pricing of $525 for the 91 DD, and the fact that the release will be slow as real-world environment running and testing usually exposes final adjustments and tweaking required when any new engine is released. I have a list of the guys that initially wanted to be included in a pre-sale of this engine when available. Knowing that situations change over time, I wanted to update my list. If you would still be interested or would now be interested, in a pre-sale on this engine very soon, to help us perform live final real-world testing and feedback, please let me know here or via a PM. I will work with Novarossi to offer $130 off of this engine, ($395.00 ea.), just like we did on the 21 MITO, to get 10 of these engines running and racing. I will also create a feedback BLOG for the use of those that have been testing this engine, as well as those that purchase in this pre-sale, so feedback can be freely shared amongst the group. I will also add that anyone testing or a part of the initial pre-sale group, that is first to win a major race or set a record with the Novarossi 91 DD, will receive a new engine for FREE. The only qualifier, (for the race to qualify), it must be a race that draws 200 boats or more to the event!!!

Please let me know your interest ASAP. Thanks.



Updated Picture and Engine Details

Head insert: Turbo

Aluminum Connecting rod

Crank thread M8
 
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Sounds real tempting Ron!...I may just have to build me a new F-Boat.
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Jack,

This was a totally new marine design as with the 46 DD. Along the way since the initial prototype engines were received, typical fine-tuning changes such as timing and bowl volume adjustments, as well as cooling cap and cooling ring design and water volumes were tested.
 
Looks real nice Ron !!! Nice to see another choice to the mix for big engines! Allen Yuen with twin 91's in a hydro will be SCARY!!!!!

Brad
Yes Brad, I am sure Allan will be all over this one. We look forward to getting these engines out and getting feedback as well as winning races and setting records.
 
Looks good Ron! I like it better than the first prototype I reveived! Good job keeping it going!!!
Thanks Glenn. Martin still has the first prototype you sent to him and will soon have the updated piston and sleeve. Since he is running it in a hydro, he may never need the additional cooling!!!!!!
 
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Measuerment I got on the new 91dd (bore=1.036) --- stroke =1.082)-- rod length=(1.732--- rod ratio=( 1.600)---. center exhaust=( 188*) side exhaust ports = ( 184*) three side transfer ports are staggerd ( 122*/128*/132*)---back port=(128*) ----- r/v= (30/70)--crankpin diameter=(.257)------od of the big end of rod=(.512)----total head volume with .014 clearance (.98cc)-----The two boxest I have, there is a big warning sign on the inside cover of the box that reads--- WARNING recommended fuel blend-- 10% nitromethane / 10% synthetic oil / 10% castor oil / 70% pure methanol. J.
 
Measuerment I got on the new 91dd (bore=1.036) --- stroke =1.082)-- rod length=(1.732--- rod ratio=( 1.600)---. center exhaust=( 188*) side exhaust ports = ( 184*) three side transfer ports are staggerd ( 122*/128*/132*)---back port=(128*) ----- r/v= (30/70)--crankpin diameter=(.257)------od of the big end of rod=(.512)----total head volume with .014 clearance (.98cc)-----The two boxest I have, there is a big warning sign on the inside cover of the box that reads--- WARNING recommended fuel blend-- 10% nitromethane / 10% synthetic oil / 10% castor oil / 70% pure methanol. J.
?????
 
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Most all manufacturers recommend no more than 25%, but that hasn't stopped most boaters from increasing the nitro, lowering the compression, and pushing the nitro marine limits!!!
 
Cool! I'm excited to see how they run with the new changes!

GQ
Yes...
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Once this is off the table 67 DD project is next!!!! That will make a lot of mono, hydro, and scale guys happy!!!!!....
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OH Hell Yeh!!!!!! lets get this one goin. BETA tester standing by
Thanks Rick. You got it!!!...
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BTW, caught a math error thanks to Shane. First batch will be $395, ($130 off of the $525 selling price), as promised. Thanks.
 
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