IMPBA Super Sport Engine Tips?

[Steve Smith]

I've been away from the hobby for 10+ years, and I'm currently building a Thunderboat to get back into racing. In the past, I never used 'stock' engines so this will be a new experience. I realize that no mods can be made to the 260PUM, but I was wondering if there were any tips to preparing a new engine that might improve performance.

- Is there anything to be gained by changing gaskets (rules seem to allow copper base gaskets.....not sure about teflon intake gaskets)?

-What about checking/truing the crank?

-Do you stick with stock bolts or go stainless?

-Do you dump the Champion plug for an NGK?

-Should I stick with 8-10oz / gal of premix?

-What's the best pipe for stock engine in a Thunderboat (Blazer, Lauterbach)?

-Can someone clarify the rule on pull start vs pulley? The rule states "Recoil pull start must be the primary method of starting. EZ Start and pulleys are acceptable." Which is it....mandatory pull start or no?

I'd be interested in anything else you care to share here.
Thanks!
-SS

 

[Lamar_Huff]

My 2 cents:

- Is there anything to be gained by changing gaskets (rules seem to allow copper base gaskets.....not sure about teflon intake gaskets)? Not really

-What about checking/truing the crank? Can't hurt and it's not against the rules

-Do you stick with stock bolts or go stainless? Stock bolts seem to work just fine

-Do you dump the Champion plug for an NGK? Dump the Champion plug, I've seen the insulator around the electrode break and grenade more than 1 engine

-Should I stick with 8-10oz / gal of premix? Yes sir, I run the same in my SS motors as my Mod motors (10oz of Klotz w/ Castor)

-What's the best pipe for stock engine in a Thunderboat (Blazer, Lauterbach)? Zipp Kits pipe works great and is cheap too

-Can someone clarify the rule on pull start vs pulley? The rule states "Recoil pull start must be the primary method of starting. EZ Start and pulleys are acceptable." Which is it....mandatory pull start or no? You must leave the recoil pull start on the engine. If you want to use a belt to start it get one of the collets w/ a built-in pulley and use that to start the boat with (don't ask me why, I didn't write the rules)

Later,
Lamar

 

[Mike Hughes]

What Lamar said. It is different for NAMBA. If you ever decided to race with them. Just a few other changes. Just make sure you not buying the china versions of zen part for your motor. East to do and get disqualified.
Mike

 

[LohringMiller]

The pipe is everything in the stock motor. Because the intake side is restricted compared to mod motors, a pipe that creates a strong low pressure wave (suction) gives the best power. We compared several pipes to our standard M&D pipe. A billet pipe I designed worked best. Accuracy in manufacture is important. Fabricated versions haven't worked as well.

Lohring Miller

 

[Dave Gilles]

though Im not willing to argue with the top notch advice you already have been given, I have seen these 1" titanium CC racing clone pipes make already very fast, record holding SS setups go a few mph faster.


https://www.ebay.com/itm/310988833588

 

[Steve Smith]

though Im not willing to argue with the top notch advice you already have been given, I have seen these 1" titanium CC racing clone pipes make already very fast, record holding SS setups go a few mph faster.


https://www.ebay.com/itm/310988833588

Dave,

Does someone make a 90 degree 'drop' style header that works with this pipe? I'm a bit confused by what's going on at the stinger end of the pipe....could you explain?

-SS

 

[Steve Smith]

Thanks for all the info folks!

 

[Dave Gilles]

Dave,

Does someone make a 90 degree 'drop' style header that works with this pipe? I'm a bit confused by what's going on at the stinger end of the pipe....could you explain?

-SS

here is what I think youre looking for
https://fadshobbies.com/product/header-dropped-90-degree-stainless-steel-1-25-4mm/