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the d17 stroker in a d16 block is becoming more prevalent and so im gaining some interest in it.

what seems to be the reason it wont reach higher revs when completed?
is it the rods not taking the abuse or is it just the longer stroke? im clueless when it comes to the d17 setups

thanks
 

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ej1
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the d17 stroker in a d16 block is becoming more prevalent and so im gaining some interest in it.

what seems to be the reason it wont reach higher revs when completed?
is it the rods not taking the abuse or is it just the longer stroke? im clueless when it comes to the d17 setups

thanks
The longer stroke. The pistons have too far to travel to keep up with the flame front. Power starts dropping off. I'm thinking you'd be done by 7500-8grand tops, for a reliable build but I hope to here a differing opinion with head work&cam. Big turbo.

You will reach a piston speed you won't want to go beyond at a lower rpm than it took to reach with the shorter stroke. Longer rods will slow down the piston speed but that's not the case here.
The internal friction is higher putting more stress on the skirts when you rev high.
But the drive ability torque would have to be a noticible increase with the d17 over a d16 stroke. I experienced quite a lose in low end torque going to a d15 stroke from a d16 despite aggressive n/a timing that helped bring most of it back.
You'd probably have use able torque all the way from 1000rmp. With the d16 I noticed it starts at 1500, and 2grand on the d15 respectably, running the same d16 cam.

It wouldn't have been so hard for Honda to lower their compression height and lengthen the rods back in 1988 unless that's costing them too much steel for production. Even on the d16's. I would think less aluminum in the pistons would be a trade off. I think they didn't want to make separate rod tooling for d16's than jdm d15b's.
 

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ej1
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of course, anything better than stock rods, if end up getting aftermarket rods...might as well do pistons, whether it be for NA or boost
I guess you could use shaved d16 or fjt jdm d15b custom rods with vitara's.
 

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The longer stroke. The pistons have too far to travel to keep up with the flame front.
I've heard this a few times, but it doesn't really make sense to me.

First, the piston will induce turbulence in the cylinders as it travels down the bore, and the currently burning mixture should be spread everywhere. I guess I can see incomplete burning being an issue if the piston/chamber shapes suck, but that would be a problem at lower speeds too.

Second, even if the piston is "outrunning" the flame front, the flame isn't exerting a force on the piston; the pressurized gasses are. Although the pressure distribution in the cylinder will be somewhat affected by the bore/stroke ratio, the total pressure exerted on the piston for a given mass of fuel with a given LHV is mostly affected by the burn rate profile, engine speed, and compression ratio.

Considering there are Pro Stock and Pro Mod engines that have mean piston speeds in excess of 7000 fpm, a d17 stroker should be able to rev past 10000 rpm based on piston speed and laminar flame speed alone. Of course, that will never happen for other reasons.
 

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^^^^^ +2

Further to that, the reason that a D17 does not like to rev is long stroke and SHORT rods compared to the stroke.

Burn rate and therefore rate of pressure build up vs rate of increase in volume was an issue in F1 at about 18000 rpm. That is twice the RPM a D is likely to reach even when hot rodded.

Stroke has nothing to do with it. Volume of chamber and distance from spark plug does have a lot to do with it. Bigger bore actually hurts it more than longer stroke as that creates a wider flatter chamber with the gas near the bore being further from the plug. This is actually the reason why tight quench works so well. The charge is squished out of the areas that are furthest from the plug back toward the plug creating turbulence that spreads the flame quicker and therefore increases the burn rate and therefore rate of pressure increase.

Also the shorter rod to stroke rather than the longer stroke causes the piston to move away from TDC quicker so the rate of pressure build up is reduced as the piston movement increases volume quicker.

The shorter rod to stroke also increases piston skirt friction on the cylinder wall.

Also the longer the stroke the higher the piston speed so the more likely it is to break a piston.

Also the longer the stroke compared to the rod, the greater the angle the rod reaches and the more bending force is applied to the rod beam.
 

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The shorter rod to stroke also increases piston skirt friction on the cylinder wall.

Also the longer the stroke the higher the piston speed so the more likely it is to break a piston.

Also the longer the stroke compared to the rod, the greater the angle the rod reaches and the more bending force is applied to the rod beam.
This is what I was going to say... Pat beat me to the punch.
 

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so could a deck plate be installed for longer rods to help with high reving?
If you want to spend money yes I have a set of Crower Rods for a B18 and 95mm stroker crank to give it the same rod to stroke ratio as a B16.

Problem is that NHRA changed the rules in the middle of the build and would only allow additional deck height of .500 inches. when I needed .788 inches.

Of course you would have to custom sleeve the block and drop the plate on with a gasket in between.

I had Cometic make the sandwich gasket and ARP told me the H22 Head studs were a perfect length in my B18 for what was needed.

Last problem with additional deck height is timing belt length.......

I fixed my problem with WP block off and electric pump, custom diameter tensioner.

All in All there was $10k in the short block in custom machining and custom parts. Shortly before the pistons were finished from Wiesco I wrecked the car and parted the project out to buy a house.

Moral of the story is.... Its not worth it. I was going for Fastest All motor ever when Skunk2 had Shagday driving the Integra
 

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Jakers toyed around with the idea of a deck plate on a D, but it never happened. a lot of people suggested he go other routes.

something about D's with deck plates not sealing worth a shit
 

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Jakers toyed around with the idea of a deck plate on a D, but it never happened. a lot of people suggested he go other routes.

something about D's with deck plates not sealing worth a shit
 

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Jakers toyed around with the idea of a deck plate on a D, but it never happened. a lot of people suggested he go other routes.

something about D's with deck plates not sealing worth a shit
The only way it can seal is to actually weld the deck to the block with the extended sleeves then mill any warp out of the block. But tig welding all those oil holes and passages would be a lot of heat to put on a block to get it straight again.

My design I had for my block pinned the sleeves almost like a block guard but pinning every 45 degrees to keep the deck from shifting and it was also dowled like the bkock and head.

Largest problem is sinking sleeves

I have not done the math but is it possible to use the D17 crank and rods with custom pistons moving the wrist pin up to compensate for the stroke difference?

Edit the D17 Crank is 4.4mm (.1734) larger stroke in theory moving the wrist pin up in the piston that much may be possible in the D16 block.
As they both use the same rod length you can not rev the piss out of it. as it is a 1.48 Rod to stroke ratio vs the D16 at 1.52.

I still like the 1.745 of the B16 Even my B20 I take to 9200 at 1.54. I fear the rod to stroke ratio on a stock cylinder wall will cause problems as well as rods and piston side skirts and rings lands at the D17 1.48

Your making me consider a new project like a sleeved D16 stroked decked with 79mm bore and like a 1.6 or better rod to stroke ratio.
 

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Good stuff. I'm glad to be set straight on these issues. Man I wish Honda would of had the decency to make D-16's with a longer rod in the beginning then the compromise they came up with.
 

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Good stuff. I'm glad to be set straight on these issues. Man I wish Honda would of had the decency to make D-16's with a longer rod in the beginning then the compromise they came up with.
Honda did not build a race car LOL it was a daily driver. Hood only so tall and suspension lining up axles only gives so much.
 

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Honda built the D16 and D17 for a purpose. The rod to stroke they chose and the overall engine height and weight suits that purpose well.

A D17 uses the same deck height block and rod length, so the extra stroke is offset by a lower compression height in the D17 piston. This makes for a tight ring package and the top ring as close as you would dare to the top of the piston.

I am toying with a deck plate and custom sleeves.

A H22 belt I think (I have the details in a folder somewhere) allows about an extra 12 mm on the deck
 

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Honda built the D16 and D17 for a purpose. The rod to stroke they chose and the overall engine height and weight suits that purpose well.

A D17 uses the same deck height block and rod length, so the extra stroke is offset by a lower compression height in the D17 piston. This makes for a tight ring package and the top ring as close as you would dare to the top of the piston.

I am toying with a deck plate and custom sleeves.

A H22 belt I think (I have the details in a folder somewhere) allows about an extra 12 mm on the deck
I like you LOL
150mm rod will get you a 1.59:1 RS ratio but that's like 38mm taller and you have to multiply that by 2 as the belt crosses the deck twice so your looking at a 76mm longer belt.

I never thought of using a stock belt length as a base reference point for deck height. U R Smart!
 
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