So I have contemplated building my B16A block forever, but I found a decent deal on a running B18C block finally. I just have a question about the pistons I should be using. Since I have a B16A head on a B18C block, the compression is lowered (according to what I've read). I still want to shoot for the 10:1 compression ballpark. What compression pistons should I be in the market for?

Thanks. Feel free to give me any input on this topic. If you have experience you feel like sharing, go for it.

 

Power goal?

 

400-450.

But my question was pretty independent of power. Wasn't it?

 

Jus get the wiseco 9.7-10.1cr pistons.... its not going to be exactly 10.1 but will be close enough... no need to over think this one.

 

I do over think things. Guess it isn't a big deal. Good enough for me.

 

Have you used a compression calculator at all? Haha... it is usually about 0.2 - 0.5 a point lower so shoot for 10.5:1 for your wants. And yes, this question is independent of HP............

 

Nope. Last time I used a calculator I was laughed at hopelessly. That was about a year ago and it was a boost/HP calculator, but whatever. Point being, bad taste in my mouth.

Basically, the 0.2 to 0.5 is what I wanted to know. I'll keep that in mind. The info I read from 2005 made it seem like 10.5:1 will become 8.9:1 or something extreme.

 

Are you going to recommend him a cast piston if his power goal is 400+? Yes, it is power dependent.

 

Ah. Well, I guess I should have mentioned it was going to be Forged internals regardless of piston compression. Wiseco is what I've been looking at.

If I stay under 400 wHP, would you suggest something like Nippon on stock rods?

 

If you have even the slightest urge to go past ~400 hp then you might as well just go forged now. Then the only real limit will be the stock sleeves.

 

Theirs plenty of Honda Compression calculators floating around of which we all know which ones they are or you can run the math your self if you have all your measurements in spec

I made this thread years ago in the AM forum since I felt everyone outta be able to run estimates from their own math, its now a sticky in the FAQ's...
DIY Compression Ratio Calculation - Honda-Tech

Generally the compression height (distance between piston pin centerline and quench pad) and dome/dish volume is what varies between OEM to Aftermarket pistons if seeking the static compression ballpark with aftermarket piston's..

 

He said what compression pistons should he be using, NOT what style, brand, metallurgical composition, etc... compression. Compression is absolutely not power dependent, but has obvious limitations depending on fuel. But since you asked, sure why not? Cast pistons for everyone! Where's that highest horsepower stock block thread when you need it...

If I open up an engine, no matter what kind or for what reason, I put a forged rotating assembly in it. Yeah, even my lawn mower... well maybe not that, but everything else.

 

I've got my answer. It has been awhile since I looked at the stickies. That is just my bad. Thanks.

 

This cracked me up. Anyone wanna make a hard core briggs engine with forged internals, bigger carb, and a 150 shot of nitrous??? Lets get some custom cams and high rev valve springs so it can make some real power!

 

"More HP than you can hook up. The
engine is 28.86 cubic inches or 476cc's. It
has been de-tuned to 52hp to help you get
your chassis hooked. If you would like 60+
hp, we can and will tune it for that before
shipping it to you."

What was that about lawn mower engines?

 

Ooohh yeahhh... I am going to put that on my FWD lawn mower ASAP!!! Reverse light pole donuts FTW!!!

(People that push mow and have posts / light posts know what I am talking about. )

 

Hell that motor would be fun to put into a racing kart frame, go kart, or a small go kart sized dune buggy.

My neighbor might buy the motor from my 05 R1 to put in a small dune buggy he just bought. A 190hp 200mph dune buggy sounds like a smart idea lol.

 

That IS a kart racing engine. Dirt oval, specifically.

 

Ever seen a belt drive zero turn with a bored out carb, and raised compression? If I throw both wheels into full throttle on anything but blacktop, I'll sit there digging out holes. If I do it on blacktop...I'll flip it.

...yes, I was bored one weekend out at the farm.

 

I was joking when I said building a forged briggs 5jp but a site sells billet rods for 60 bucks, billet cranks for under 500, and all sorts of go fast parts. Comp cams have huge cam selections for around 170 that have powerbands from 4k-9k.

I wanna build a nitrous fed briggs...

 

I used to race karts. I know the engines all too well....

But I dont think they have gone forged yet. The billet aluminum stuff is holding up just fine.

 

I shouldn't even admit this because this just shows I was raised in the south but racing a lawnmowers is a blast. Running a built Briggs and Stratton on race fuel in a lawnmowers that is top heavy and can do every bit of 70. Then you throw in somebodys back yard who had a tractor to make a dirt circle and a bunch of alcohol.

 

Sounds like a good time

 

I had a ride on lawn mower once. Lets just say those lil baby wheels up front don't steer very well when you're hauling ***.