rx8wannahave

Hello,

I've heard people say that if an engine is blue printed then it will make more HP and stuff. What exactly is that and can it be done to a rotary?

Also, what are the historical things that people have done to rotary engines to make more power (less SC/Turbo)

Thanks for the knowledge!

s13lover

It's basically taking a stock motor and making all the dimensions match perfectly within the factory specs. Believe it or not, motors don't come perfect from the factory. They're full of small variations (thousands / ten thousands of an inch).

wakeech

'perfect' is a relative term.

the tolerances of a MODERN engine leaving the factory, for the important mechanical bits, are much better these days and don't have to be fooled with. but with components that are cast (heads, manifolds, rods, other things) variation can be in the hundreths of an inch.

blueprinting is really just bringing the tolerances in tighter, and is basically the baseline preparation for building a really good motor (whether you're going tomodify its mechanical operation or not).

rx8wannahave

OK...thanks for explaining, that's what I thought but I was not sure. I wonder has anyone or can a Rotary be blueprinted?

Detroit RX8

Any engine can be blueprinted, it's just a matter of cost.

rx8wannahave

Ah, probably not worth it right?

HP per $ is the KEY!

crossbow

Blue printing is also a decent way to gain power under "strict racing regulations". Some classes won't allow various engine mods, but will allow "factory spec" tweaking.

Blueprinting can snag you another 5-10 hp over another stock vehicle...which when everyone is running the same specs, ends up being an awful lot on the race track. Just look at how much money the spec miata racers spend on blueprinted engines...just for an extra 5 hp over the guy next to them.

Technically due to variables in manufacturing, its possible to not gain ANY power from blueprinting an engine. If you've ever heard of factory freaks, thats what occuring there. Basically an engine with just the right type of tolerances, in just the right combination, outputing 10-40 more whp then the whole lot of normal produced cars. aka if you tried to blueprint an engine with already flawless tolerances, you won't be looking at any power gains.

wakeech

if you wanna play, you gotta pay. there aren't many easy way outs with a good motor.

Red Devil

With blueprinting, usually comes the rebuild with higher quality parts than what you started with. I can't confirm, but have heard that just switching to ceramic apex seals is good for a couple more hp just because of their better structural properties.

And more power from an NA rotary can come from anything you can think of with a piston engine, less specific parts to either rotary or pistons - cams, heads, valves, etc...

babylou

I know in the old Showroom Stock classes the engine components could not even be modified one iota. The way to get more power was to go through the entire production lot of components and cherry pick the best combination. Choose the crankcase with the shortest deck height, the heads with the smallest combustion chamber and voila you have just bumped the compression ratio nearly a point.

zacknolden

Hmm.. I asked my father about it. This is what he said to me, "Most internal stuffs/parts are de-accented, hand washed and inspected pins, pistons and connecting rods are pin fit to specification"

Rhawb

Zombie thread!

Made me think Wannahave was returning...

swoope

iTrader: (5)

wow,

two five year old thread bumps in one night, you must be tired..

and the info from your father is mostly wrong. it is about making sure clearances and weights of everything are exactly the same.

beers