crank swap

[JAYRACER18]

i was think of putin a b18 (GSR) crank in a b16 (SI) block and putin custom rods you think that will work :eek:

[candymanjl]

as long as you get the right length rods, get ones that're too long and your pistons will be bashing you cylinder head :) that would be bad.

(ssssshhhh, don't tell anyone, but if I build my B16A bottom end, my gs-r crank is going in there ;) )


B16A Turbo CRX

[JacksonSi]

Nothing like a stroked motor! Ha! ;)

"Money is the root of all problems"

[Camuman]

i be strokin!!!!!!!!

>CURRENTLY SLEEPING 91 Z28 will be resurrected!!!
EAT, SLEEP, BREATHE CHEVY.
>NEW RIDE 2002 VW JETTA 1.8t 5M(Mad Boost Machine)
BMC CDA intake
APR Chip(Stock,93 octane,Valet,Race, FCE/TB AM)
ATP 3" dp with !cat
N75 Race Valve
ATP lower motor mount

[candymanjl]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Camuman:
i be strokin!!!!!!!!

[/quote]


he he, I remember that song :)


B16A Turbo CRX

[nos_b-16]

Thats a good idea if you got the crank

[candymanjl]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>

Originally posted by Bottle Baby:
Thats a good idea if you got the crank

[/quote]


actually... ;)

got one in my room from the gs-r block I destroyed (snapped a rod, but saved the salvagable stuff, like Mr. Crank)


B16A Turbo CRX

[GSteg]

no no no!! please don't ruin the B16's 1.74 ratio. it's the best ratio in any honda motor up to date! you'll increase sideloading which is a no-no. :D

[candymanjl]

yeah maybe, but the difference in power was night and day between the 1.8L and the 1.6L, plus it spools the turbo quicker with more air pumping.

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B16A Turbo CRX

[jayman320]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by GSteg:
no no no!! please don't ruin the B16's 1.74 ratio. it's the best ratio in any honda motor up to date! you'll increase sideloading which is a no-no. :D[/quote]

Just cause it has a perfect r/s ratio dont mean shit, a bi6 is a destroked ITR without the head valvetrain characteristics. A toda stroker kit for a b16 to 1.8 liter is the same crank as that of a ITR b18c5.

I have ls/vtec, worst r/s ratio ever...but look at these

b18c1 1.58
b18c5 1.58
b18a1 1.54
b18b 1.54
b17a1 1.62
b16a1-2-3 1.74 <--near perfect r/s
H22A1 1.58
H23A1 1.49
H23A4 1.49

Why did honda make engines with poor r/s ratios, yes ideal r/s is 1.75. Honda is know for the long lasting durability of their engines that last as long as 100,000+ miles. Why would they build engines with poor r/s? Engines that are rev capable of 75-8000 rpms. Research about it...

http://www.onlineshowoff.com/member/car/StealthySleeper83DC553/DSCN0470.jpg

Low Key 94' integ 4 door
13.8 w/ full interior

mods:
-ls/vtec/ls block & JDM GS-R head(port & polished)/ITR internals/Skunk2 intake manifold/ITR throttle body w/ Stage 2 Bore/B&M Fuel Regulator/Upgraded Valvetrain/AEM Cold Air Intake/ITR Headers/Stealth Straight Pipe Exhaust w/ Stock Tip/ITR ECU/ACT stage 3 Clutch/Stage 1 Short Shifter/17" C2 Racing Harts/Skunkworks Coilovers/Tokico 5 Way Adjustable Shocks/ITR strut bar, rear strut, & tie bar(custom fitted)/Wings West Body Kit(Lip,Side Skirts,& Rear)/Titanium Racing Pedals/ITR Gun Metal Shift Knob/ITR Momo Steering Wheel/NGK Spark Plug Wires/Denso Iridium Spark Plugs/Red ITR JDM Valve Cover/Custom White & Grey Vynyl Interior/Infinity Kappa Speaker System/Pioneer Headunit/Blitz Air/Fuel/Oil Pressure Guages/Apex-i V-AFC, Brembo Dimpled & Slotted Rotors

Upcoming Mods: JDM ITR Conversion, Carbon Fiber Hood, Tien Suspension, 15" Bronze Volk Gram Lights Rims, Spoon CF Lip, Spoon Flywheel

[GSteg]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>just cause it has a perfect r/s ratio dont mean shit, a bi6 is a destroked ITR without the head valvetrain characteristics. A toda stroker kit for a b16 to 1.8 liter is the same crank as that of a ITR b18c5 [/quote].

wait..so a B16 is just a destroked B18C5? interesting..what about the first generation B16 engines?

[GSteg]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>

Why did honda make engines with poor r/s ratios, yes ideal r/s is 1.75. Honda is know for the long lasting durability of their engines that last as long as 100,000+ miles. Why would they build engines with poor r/s? Engines that are rev capable of 75-8000 rpms. Research about it...
[/quote]

i guess because not all honda's need to rev high like the B16 (ie. B20B/Z) well i thought since a b16 was a high revving engine, stroking the engine would defeat the purpose of that high revving machine because it wouldn't be safe to rev pass ~8000RPM.

here is what i found from another forum:
" rod ratio is calculated by taking the connecting rod length and dividing it by the crankshaft's stroke.

A good rod ratio is considered to be 1.65-1.77. Some people say the ideal rod ratio is 1.75:1 or 1.77:1. Guess what? the Civic b16a 's rod ratio is 1.75:1 and the CTR b16b is 1.77:1. Co-incidence? I don't think so. Honda
has lots of race engineering experience with high revs in it's Superbike and Formula 1 N/A engines...like 18,000+ rpm. They trickle this knowledge and tech down to us plebs or common folk in a street car...cool huh?

Unfortunately, the integras got a low or short rod ratio: b18b 1.54:1 and B18C 1.59:1...not ideal.

So what is the importance of rod ratio anyway?

rod ratio describes piston geometry (3 things):

1. piston speed away from TDC and BDC
2. piston dwell time at TDC
3. the amount piston sideloading against the cylinder wall as the piston
travels up and down the swept volume.

So rod ratio can affect how high you can rev, since a low rod ratio places more side loads on the wall.

The rod ratio in a naturally aspirated engine affects how well the cylinder is filled and dictates cylinder head port size. The faster the piston pulls away from TDC on the intake stroke means you can get more suck to fill the cylinder. How fast the piston transitions or flip-flops from squeezing the exhaust gas out at TDC for the exhaust stroke to dropping down and begin filling on the intake stroke (i.e. TDC dwell time) affects your cam overlap and cylinder filling.

low rod ratio engines have short piston dwell times at TDC and fast piston speeds away from TDC (or faster piston speed dropping down on the intake stroke compared to a long rod ratio). So a low rod ratio motor
generates high flow velocities for filling through the intake port at low-mid rpm. These engines like bigger cylinder head intake port sizes compared to a long rod ratio motor like the Civic Si's b16a.

Low or short rod ratio ALL MOTOR engines like a cam with more lobe separation angle, more duration, and more cam overlap, since it has short piston dwell time at TDC and needs help scavenging in fresh air/fuel.

This all has to do with revving ability, proper intake port sizing, and cylinder filling IN AN ALL MOTOR SETUP which depends on passive filling using lower pressure in the cylinder (called pressure gradient) compared to the atmospheric pressure (14.7 psi). In turbos and SC's, you push in the air to fill the cylinder and so rod ratio plays a very MINOR role in cylinder filling.

JUST REMEMBER: don't rev the sh*t out of a low rod ratio engine (all motor or boosted)...the shorter rod ratio still causes the piston to sideload the cylinder wall harder causing more risk of a piston going through a wall, the higher the rpms go (keep it under 8100 rpm)."



so when the displacement is increased, the r/s ratio becomes smaller, which means the engine will experience more sideloadings....i'm sure you know this already :)

but if i ever wanted to increase the displacement, i'd bore out the engine :o

[GSteg]

also, the bigger displacement you have, the harder it is to get a perfect rod to stroke ratio, hencing the r/s of the engines you listed declines as the displacement gets larger.

the higher revving r/s ratio is more of a race inspired thing...

[Paradox]

wow, that is astonishing. good research :cool:

____________________________
SuperPimps LTD. Est'd 2002
Honda Driving Nut Scratchers
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[candymanjl]

the problem is to keep that "perfect" ratio your motor gets huge in size once the displacement gets bigger. keep the B16's ratio on a H22A and it would be a lot taller, which would make it heavier, and how much would it really gain?

papadakis is running low 8's on a built prelude motor with the non-ideal r/s ratio, lisa kubo was running a 2.0+L B16 setup last I saw her in a mag. so on paper it might make a difference, but in the real world, does it matter?

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B16A Turbo CRX

[GSteg]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by candymanjl:

papadakis is running low 8's on a built prelude motor with the non-ideal r/s ratio, lisa kubo was running a 2.0+L B16 setup last I saw her in a mag. so on paper it might make a difference, but in the real world, does it matter?

______________
[/quote]

their engine are reliable anymore. they would have to rebuild the motor once in a while to keep it running.

[candymanjl]

that's true, the big boys are rebuilding after every couple events, but they're making at least twice the HP that most people are gonna make, and I haven't seen papadakis DNF due to engine failure (maybe he has?).

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B16A Turbo CRX

[GSteg]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by candymanjl:
and I haven't seen papadakis DNF due to engine failure (maybe he has?).
[/quote]

maybe thats why they rebuild the engine?i don't think they want to take chances during their runs. :p

[This message was edited by GSteg on July 15, 2002 at 11:19 PM.]

[9seccivic]

we had 280 runs on our engine, before i dropped some valves, the bottom end is perfect and its a stroker. that engine went 9s

[GSteg]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by 9seccivic:
we had 280 runs on our engine, before i dropped some valves, the bottom end is perfect and its a stroker. that engine went 9s[/quote]

cool. i used to live next to a guy that had a 97 civic coupe with an h22 made for drag racing only. he put on a stroker kit that raised the displacement to 2.5 liters. it had a lot of power, but after about a season, the rod on cylinder 3 and 4 snapped, sending it out the block. poor engine :( his goal was to run 9's or low 10's, but after the engine broke down, he had financial problems so he could never reached his goal. oh well..

[candymanjl]

well, I had my stock gs-r block snap a rod and helicopter the block at only 8psi. :( made for a nice smoke screen in the rear view when it happened though :D

http://home.attbi.com/~candymanjl/deadengine/crackedblock2.jpg

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B16A Turbo CRX