colt45.5

Ive searched high and low, and am currently seriously contemplating the 95mm scat crankshaft and custom piston and rod set from dynamic autosports, along with a 11.5-12.5:1 piston.

I havent found much on the items, however the block i have is a sleeved 85mm bore r block and needs to go 20 over at least. So im ruling out using it for boost.
As far as headwork it remains a stock 95 gsr head with peak intake manifold, springs, retainers, and dynamic stage 3 cams.

Opinions? Anyone ever try anything similar to this for drag racing?

I plan on using a 4.785 final drive gsr trans, and the motor is going into a 1700 lb eg hatchback.

Veris

Lots of low end power. 2207cc.

I bet you'll make 175ftlb (to the wheels) with that combo.

You will want to keep the revs down (8000 RPM and less) however as peak piston accelerations are 112% higher with that motor over an ITR. It also will breath poorly at high RPM so it'll require a long duration camshaft and fairly high CR; 12:1.

I believe Eric's Racing has an all motor race engine that is a similar set up.

colt45.5

well that sounds like good news. I just want this unit to be faster than my gutted 98 ex coupe with b18c1 and pct pistons.

Seeing how the chassis i am switching to is near half the weight, this should be a fun little whip.

ill keep everyone posted as the project moves on. And its sounding like my only enemy may be traction.

Veris

I should have added that a 4.785 final drive is wasted with a torque monster like this. 1st gear will be a waste and on the strip a 4.785 final drive might push you into 5th gear at the top of the 1/4. A definite no no! Stick with a normal gsr or b16a/itr gearing. On street tires a LSD will almost be a requirement.

A 4.785 final drive makes since for a very high reving low torque motor. ie: 200whp B16A reving to 9000+.

I should also stress again that this engine combination won't last long if you rev it. You really want to keep it at or below 8000 RPM at the track and 7500 or less on the street (maybe even 7000 on the street).

Combustion Contraption

big bore short stroke is where its at. when will people reliaze this?

C2Imports

big bore short stroke, thats what im talking about

Fkned

You're deffinately gonna need a very good head for that setup.Maybe a square port GSR.

JDM Type R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LsVtec92Hatch &raquo;</TD></TR><TR><TD CLASS="quote">big bore short stroke is where its at. when will people reliaze this?</TD></TR></TABLE>

Y do you say that ? i dont know if i want to stroke my Jdm itr or not. so maybe you can go in to it for me he pros and cons of both "big bore short stroke vs big bore slong stroke" im going with Areas piston (12.5.1) Compression and keepping my 10k shift point my set up is:
JDM integra type R motor
Skunk2 stage-3 cams
Skunk2 stage-3 valve springs
Jun stage-3 titanium retainers
Skunk2 cam gears
P-30 ecu
Mugen program (10K rpms)
RPM 70mm Throttle Bodies
370cc RC injectors
B&M Fuel pressure reg
NGK racing sparkplugs (7) Hr
Unorthodox Racing Red crank pulley
MSD racing sparkplugs wires
JDM APEXi VTEC Controller (V-AFC)
Port matched intake
JDM APEXi n1 B pipe exhaust
6al MSD ignition
J’s racing intake
ST Stainless steel valves (Nitrile coated)

Combustion Contraption

When you lengthen the stroke, it has an direct effect on the powerband. You dont see many b series turning 10k rpm with 95mm strokes. At least not for long. If you want to increase displacement with stroke, shorten your rods and get a custom piston/wristpin setup.

Combustion Contraption

Let me clarify what i said a little more. What i meant was, if you want to stroke it using a longer stroke but you still want to keep your 10k redline, then you should shorten your rods and get a custom piston/wristpin setup. Theres nothing "wrong" with lengthening a motors stroke, but youre going to move the powerband down, i wouldnt rev past 8k with a 95mm stroke and thats with upgraded internals, balancing and blueprinting, the works. However if its stricly a race motor in a race car, then **** it. Take it to 10k, it only has to make it down the track once right? Get ready for some rebuilds.

GOLDBERG

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDM Type R &raquo;</TD></TR><TR><TD CLASS="quote">

Y do you say that ? i dont know if i want to stroke my Jdm itr or not. so maybe you can go in to it for me he pros and cons of both "big bore short stroke vs big bore slong stroke" im going with Areas piston (12.5.1) Compression and keepping my 10k shift point my set up is:
JDM integra type R motor
Skunk2 stage-3 cams
Skunk2 stage-3 valve springs
Jun stage-3 titanium retainers
Skunk2 cam gears
P-30 ecu
Mugen program (10K rpms)
RPM 70mm Throttle Bodies
370cc RC injectors
B&M Fuel pressure reg
NGK racing sparkplugs (7) Hr
Unorthodox Racing Red crank pulley
MSD racing sparkplugs wires
JDM APEXi VTEC Controller (V-AFC)
Port matched intake
JDM APEXi n1 B pipe exhaust
6al MSD ignition
J’s racing intake
ST Stainless steel valves (Nitrile coated)
</TD></TR></TABLE>

what kinda power u making??runnin 11.1cr?

colt45.5

Just because you cant rev it to 10 doesnt mean it wont be fast.

theres 8 second mustangs that rev to 6 im sure.

im shooting for displacement and torque.

colt45.5

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDM Type R &raquo;</TD></TR><TR><TD CLASS="quote">

Y do you say that ? i dont know if i want to stroke my Jdm itr or not. so maybe you can go in to it for me he pros and cons of both "big bore short stroke vs big bore slong stroke" im going with Areas piston (12.5.1) Compression and keepping my 10k shift point my set up is:
JDM integra type R motor
Skunk2 stage-3 cams
Skunk2 stage-3 valve springs
Jun stage-3 titanium retainers
Skunk2 cam gears
P-30 ecu
Mugen program (10K rpms)
RPM 70mm Throttle Bodies
370cc RC injectors
B&M Fuel pressure reg
NGK racing sparkplugs (7) Hr
Unorthodox Racing Red crank pulley
MSD racing sparkplugs wires
JDM APEXi VTEC Controller (V-AFC)
Port matched intake
JDM APEXi n1 B pipe exhaust
6al MSD ignition
J’s racing intake
ST Stainless steel valves (Nitrile coated)
</TD></TR></TABLE>

Sell the items in bold, and have someone tune the p30. Just my imput, then youd have money for even more mods.

nice setup tho.

ryanplayjoint

Import Tuner magazine is doing a B-series build shoot-out between some great honda engine builders. Rs motoworks has a 81.75 bore and 95mm stroke. The builder Mike Coughtrie says that he expects 100k out of the engine. JG is attempting to run 12:1 on 91 octane. I think on an engine dyno 91 octane can be had with 12:1, but if the engine was in a car I think it would detonate. Just my 2cents.

Combustion Contraption

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ryanplayjoint &raquo;</TD></TR><TR><TD CLASS="quote"> Rs motoworks has a 81.75 bore and 95mm stroke. The builder Mike Coughtrie says that he expects 100k out of the engine. </TD></TR></TABLE>

*sigh* once again, what i said was, that you could have a 95mm stroke, but i wouldnt rev it to 10 grand. Are you understanding the concept or am i wasting my time?

H2nr

86mm bore is not very streetable. There is only about 5hp difference between 85mm and 86mm so I would do 85mm.

diulay_pkjai

If the block is sleeved and the internals are balanced, why can't it rev to 10k reliably? I know the stress on the cylinder wall will be high, but the iron sleeves should be able to handle it. The pistons, rods and crank are balanced, so they shouldn't be a problem wither. I'm just curious why does a little bit longer stroke would limit the rpm this much.

Veris

Piston speed is the answer ussually given, but the real answer is piston acceleration. The higher accelerations effects sideloads, rod tension (failure), and bearings. Read the link below it'll give you a good explaination.

http://www.ftlracing.com/tech/engine/rsratio.html

colt45.5

The block is a darton open deck sleeved type r block. It had 85mm 9.0 pistons in it, however due to the previous tuners abilities, the skirts of all the pistons are scoured up. The cylinder walls are rusted from sitting in a garage so long. So in order for a clean bore and hone 85.5-86mm may be the only answer.

As far as the block id assume due to the longer stroke the piston skirts will have more rocking motion towards the sides of the cylinder walls. In result i expect the rings and pistons to show some damage after an extended period of time.

As far as the 12.1 compression on 91. I previously had a usdm gsr motor with pct pistons and dynamic stage 2 cams. It ran great on 91, however it took alot of time to tune the tip in. In the end it ran strong and used nearly 80% duty cycle on a 450cc dsm injector. However mated with a 2300lb 99si coupe, it wasnt spectacular and i opted to sell the motor and get started on my old hatchback.

I realize this motor idea may be a bit wear oriented. However i am fooling with a motor that either has one more season on the current sleeves or a resleve job ahead of itself. I am good friends with Eddie Kim, owner of dynamic autosports and he actually is building a nearly identical setup for the build off you are speaking of. Thats where the parts i am choosing and the combinations are coming from. I contemplated a 92mm crank as opposed to the 95. However, alot of the responces i am seeing are hearsay, rather than personal experiance.

thanks for all the responces and aid of opinions from differant sources.

Combustion Contraption

The responses im giving are not "hearsay". Theyre based on years of experience and mathematical formulas. Let me show you what im talking about.

A B16 at 10k rpm has pistons that are traveling at a speed of 5031 fpm. Thats still high. Alot higher than you should go on a day to day basis, but with the quality of honda blocks and the metallurgy of today, you can get away with it for a while. Lets take a look at the piston speed of the engine you want to build.

95mm crank @10k rpm= 6,175 fpm. Thats ridiculous! You'll pound out bearings like theres no tomorrow with speeds that fast. Better switch to titanium rods so they absorb some of the impact.

You did state in your first post that you wanted to go with a custom rod setup. What were you thinking along the lines of rod length?

indomotor

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LsVtec92Hatch &raquo;</TD></TR><TR><TD CLASS="quote">The responses im giving are not "hearsay". Theyre based on years of experience and mathematical formulas. Let me show you what im talking about.

A B16 at 10k rpm has pistons that are traveling at a speed of 5031 fpm. Thats still high. Alot higher than you should go on a day to day basis, but with the quality of honda blocks and the metallurgy of today, you can get away with it for a while. Lets take a look at the piston speed of the engine you want to build.

95mm crank @10k rpm= 6,175 fpm. Thats ridiculous! You'll pound out bearings like theres no tomorrow with speeds that fast. Better switch to titanium rods so they absorb some of the impact.

You did state in your first post that you wanted to go with a custom rod setup. What were you thinking along the lines of rod length?
</TD></TR></TABLE>
Math and theory only go so far in DRAG RACING.Please don't take it the wrong way,I'm all about R/S.This is for a race car 1,700 lbs.
My friend has the same set up made 260+ WHP and 180 WTQ with only 2 passes on the dyno.The power peak out OVER 10 K(don't quote me yet I just get off the phone w/ the tuner)
So go and do it..it's a very good set up for drag racing
The key is in tuning..

Used2beAb16

I dont ever remember him saying he wanted to rev to 10,000 rpms. It would be senseless on a 2.2 liter bseries.

That motor has the potential to make more power at 8k than the 1.6 @ 10k.

Veris

The mean piston velocity formula is a good tool for reviewing an engine design, but it is limited in that it only looks into the effect of the stroke. It only looks at half the picture.

On a stroker engine the rod length is decreased (~ equal to the stroke increased). The change in rod length affects piston to rod angle and thus side loading. It also affects PEAK piston velocity and acceleration which is were failures occur. Two engines with identical strokes will have identical mean piston velocities, but an engine with the longer rod will have lower peak pistion velocities and accelerations. The longer rod engine will also breath better at high rpm due to greater TDC dwell time.

I don't think Colt45 was picking on anyone in particular. He is just taking everything said with a grain of salt. I would too. There are VERY few people with hands on experience with a 95mm crank B series engine (excluding owners of the late 80's B20A Preludes ).

JDM Type R

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GOLDBERG &raquo;</TD></TR><TR><TD CLASS="quote">

what kinda power u making??runnin 11.1cr?</TD></TR></TABLE>

205whp

colt45.5

Precisely. In saying its heresay, i didnt mean to offend anyone in particular. Im just simply stating those with irrelivant reasoning. In reading your posts lsvtec, its clear that you have good reasoning behind your statements and i take those into reguard. Im just saying heresay for those who respond with "yea its too much it will hammer the bearings out" and give no explination of why or due to what causes. Its difficult to get a good idea what to do, because everyones got differant oppinions on differant parts. I just like to get concrete evidence of why the motors arent good and so forth. You gave concrete reasoning so its no worry.

Its just hard when someone says they are junk and shows you pictures of a motor thats blown up or some jazz. For all i know someones toddler son got in the car in the driveway and turned it on revving it to 15 grand blowing everything out the side of the block. Im just trying to get more people who have used similar setups and had luck or bad luck with. Then i can make a decision weather or not i want to take the leap of faith and try the crank and rod setup or not.

I am just trying to decide what i need to make the most power effectively. Im not looking to resleeve the current open deck darton type r block, and i have the oppertunity to get the stroker crank.

Theres also the option of keeping the 87.2mm type r crank, crower rods, and getting an 85.5-86mm piston. Some are even suggesting a 87mm. Im leary of that however since id have nearly 2 pubic hairs of space between pistons, little to no area for a gasket to seal, and i dont have wingnuts on the cam caps and headstuds to change the gasket every weekend.

This car is more or less a race car yes, but ill be driving it on the street from time to time. So id honestly like to get somthing suitable for street driving and that could put down some serious numbers and turn some serious times. My idea of a street car however is alot differant than others. All i need is a place to mount the license plate, headlights, turn signals, and taillights. besides that, theres no dash, heater, and id bet if scooter rear ended me on his moped hed prolly be residing where the passanger seat was.

Im not trying to act like the superman here, i have alot to learn and will take any advice given. Please disreguard any responce or thought of my responces being bossy or militant, i just want to learn more and have a strong car with at least a hair or reliability.

Thanks for all the responces again. its alot easier to understand with such good information.