Honda and Acura Technical Forums

racerpat94 · 12-11-2006, 12:12 AM

what exactly is involved in reversing the rotation of an engine? from the minimal and conflicting info in the searches, i have gathered that the lower end needs no modification, but that the changes needed to be made in the head, and the firing order. so..

would the intake/exaust cams need to be switched? as well as IM, fuel, EM, etc.? or do these components stay in their original places and the firing orders switched?

i saw that some race teams are reversing the rotation of their engines, just to expand their tranny options. (joetech's drag scion for one) just curious about how this works. TIA

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jays93eg6 · 12-11-2006, 12:16 PM

wow thats a 1st for me. I am in for some more on this one.

Perfectionist · 12-11-2006, 12:48 PM

I have no idea, but i would assume the engine really doesn't care much which way the crank is turning since the piston motion is up and down. The cam lobe profiles may be a problem if they are turning backwards, but otherwise should stay in their original configuration, I would think.

I would imagine the water pump and oil pump would need to be modified, as well as any tensioners.

Interesting, thought though. (You have too much time on your hands

)

Crazydave · 12-11-2006, 01:27 PM

you would probably have to flop the motor around in the engine bay too...
otherwise, you'd be going pretty fast in reverse!

I think it would be cheaper and MUCH easier to get a motor that spins the direction you want.

blinx9900 · 12-11-2006, 02:28 PM

agreed this is crazy talk! crazy! oh my god i just noticed your name is crazy dave for some reason that makes your question ok, lol how weird! i think you'd need a different starter...

02 accord · 12-11-2006, 06:54 PM

Quote:

Originally Posted by blinx9900

i think you'd need a different starter...

Rewire the car for a positive ground. That will reverse the starter. Or just fix the starter by reversing its pos/gnd.

As for the engine rotation, redo the timing belt, so that the cam(s) still rotate in the original direction.

NJIN BUILDR · 12-11-2006, 07:20 PM

[quote=02 accord]
Rewire the car for a positive ground. That will reverse the starter. Or just fix the starter by reversing its pos/gnd.
QUOTE]

That's a lot of work but it still won't work.The drive is directional.

This has been done on a B.New cams and a new tensioner set up are the biggies.Then you can run a standard rotation transmission (many more choices).

racerpat94 · 12-12-2006, 11:10 AM

Quote:

Originally Posted by NJIN BUILDR

That's a lot of work but it still won't work.The drive is directional.

This has been done on a B.New cams and a new tensioner set up are the biggies.Then you can run a standard rotation transmission (many more choices).

kseries starter and trans on a bseries? could be sweet. i guess in the long run a full K swap would be much easier and cheaper. but this concept seems really interesting.

thanks for the input guys.

thesmogman · 12-12-2006, 11:50 AM

Don't forget the head. Valves would need to be switched. Tensioner would be on the otherside of the belt. Water pump needs to be reversed. Oil pump would suck instead of blow.

I would start with a different motor that is already the way you want tit

Bense · 12-13-2006, 06:21 PM

NJIN BUILDR · 12-13-2006, 06:57 PM

Quote:

Originally Posted by Bense

It gives me a headache just looking at it......but I just can't stop looking.

racerpat94 · 12-13-2006, 07:09 PM

Quote:

Originally Posted by NJIN BUILDR

It gives me a headache just looking at it......but I just can't stop looking.

i was just thinking the same thing!

Bense · 12-13-2006, 07:46 PM

i think what they did was flip the cams around and put the head on backwards. It was some crazy euro team that wanted ram air

rip94delsol · 12-13-2006, 10:40 PM

i get it.... wait no i dont....hold i know Im confused, thats what it is.

thats alot of work. but what about the trany cant you just change the way the tranny moves the wheels...

Bense · 12-13-2006, 10:52 PM

I don't think that you'd want to reverse a tranny.

thesmogman · 12-14-2006, 09:48 AM

That one was too early for me too. (headache) but whoa.. I, I, I, dumbfounded...

.... damn.

racerpat94 · 12-14-2006, 10:36 AM

Quote:

Originally Posted by Bense

I don't think that you'd want to reverse a tranny.

definately not. especially if the tranny has helical gears. what are the two devices mounted on the each side near the oil pan? i would assume a custom alt and an custom water pump?

DonF · 12-14-2006, 11:26 AM

We converted B series 1.8 and 1.6 engines to clock rotation 10 yeare ago. You need custom cams, some work in the oil system, a dry sump oil pump, a little work in the water passages, a mugen "clockwise" water pump impeller or the one we made, plus a different belt tennsion ing system. We used a Tilton starter for a Posche and a custom starter bracket for it, I still have one of those lying around.

racerpat94 · 12-14-2006, 11:33 AM

Quote:

Originally Posted by DonF

We converted B series 1.8 and 1.6 engines to clock rotation 10 yeare ago. You need custom cams, some work in the oil system, a dry sump oil pump, a little work in the water passages, a mugen "clockwise" water pump impeller or the one we made, plus a different belt tennsion ing system. We used a Tilton starter for a Posche and a custom starter bracket for it, I still have one of those lying around.

what was your reason for doing it? what transmission did you use? custom mounts, or stock location?

DonF · 12-14-2006, 11:50 AM

We did the first rear wheel drive Acura for GT3 in the SCCA. We also did Ralt and swift conversions for Formula Atlantic and CSR in SCCA using the B-16

d16dcoe45 · 12-14-2006, 12:16 PM

That was a BTCC 2.0 liter f20b or h22 right? I heard some teams would spin the head around for precisely the reason you said--to have the intake facing the front of the car--8500 rpm ceiling and over 300 hp--they must have been doing something right!! I think that b16 in the Formula Atlantic is awesome Don,--I had no idea you didn't have to use the 4age until you told me. The current claim--even in a Toyota ad from about 2 years ago was 255 hp (crank) at 1600cc. Were your b16s in that area?

DonF · 12-14-2006, 01:07 PM

248 crank. And about $12,000 cheaper.

12-11-2006, 12:16 PM	#2
jays93eg6 Member Join Date: Feb 2006 Location: Columbia, SC, U.S. Posts: 1,016	Re: reversing engine rotation? (racerpat94) wow thats a 1st for me. I am in for some more on this one. __________________ it has a short ram intake, so the vtec hit real hard http://images.honda-tech.com/set1/smile/emwink.gif posted by kadeem71 People I have bought from or sold to: :Anderew, Rials, Vanos Pusha, SpoonEG, JUN., Bense, I Kick Squirrels, JDM SUV, TheHAtchNinja, 1990Si, DaisySi, mr.EGg, prjctwhteg., raven3dr, YKracing, Jdmb20coupe, Erik-B, HogHead, IceySC, TURBODC4TEG, AnotherEJ, Lucky-R, e she i, C_Rock77, Jay_Sensing, ED3_FTW, slickciv, Workless, too much vtAK, TURBODC4TEG, blackccoupe, alupso http://images.honda-tech.com/set1/smile/emthup.gif

12-11-2006, 12:48 PM	#3
Perfectionist Member Join Date: Dec 2001 Posts: 2,142	Re: reversing engine rotation? (racerpat94) I have no idea, but i would assume the engine really doesn't care much which way the crank is turning since the piston motion is up and down. The cam lobe profiles may be a problem if they are turning backwards, but otherwise should stay in their original configuration, I would think. I would imagine the water pump and oil pump would need to be modified, as well as any tensioners. Interesting, thought though. (You have too much time on your hands ) __________________ 2003 PWP RSX-type S "Need Help" or "Quick Question" = NO CLICK "I may not always be right, BUT I'm never wrong."

12-11-2006, 01:27 PM	#4
Crazydave Member Join Date: Nov 2001 Location: Temecula, CA Posts: 3,493	Re: reversing engine rotation? (Perfectionist) you would probably have to flop the motor around in the engine bay too... otherwise, you'd be going pretty fast in reverse! I think it would be cheaper and MUCH easier to get a motor that spins the direction you want. __________________ Crazy Dave Onate 1997 Honda Civic EX SOLD 2001 Honda Accord LX 1998 Nissan Frontier 1987 Honda CRX Si STOLEN 1 week after I got it 1994 Honda Civic Si HB

12-11-2006, 02:28 PM	#5
blinx9900 Member Join Date: Sep 2006 Location: poopfacepartytime, ca, usa Posts: 5,822	Re: reversing engine rotation? (Crazydave) agreed this is crazy talk! crazy! oh my god i just noticed your name is crazy dave for some reason that makes your question ok, lol how weird! i think you'd need a different starter... __________________ ek9.org <--- a place for the ek/ej lovers [b]FS: Racing Hart C2's 17x7 4x100 otaku squad member #004 http://images.honda-tech.com/set1/smile/emsmile.gif

12-11-2006, 07:20 PM	#7
NJIN BUILDR Member Join Date: Mar 2003 Location: Hudson, NH, 03051 Posts: 3,315	Re: reversing engine rotation? (02 accord) [quote=02 accord] Rewire the car for a positive ground. That will reverse the starter. Or just fix the starter by reversing its pos/gnd. QUOTE] That's a lot of work but it still won't work.The drive is directional. This has been done on a B.New cams and a new tensioner set up are the biggies.Then you can run a standard rotation transmission (many more choices). __________________ http://www.rrcycles.com GSR Head f/s http://www.hondamarketplace.com/show...1#post37508201

12-12-2006, 11:50 AM	#9
thesmogman Member 1988 Honda CRX My Garage Join Date: Dec 2005 Location: San Ramon/Pleasanton, CA, USA Posts: 1,592	Re: reversing engine rotation? (racerpat94) Don't forget the head. Valves would need to be switched. Tensioner would be on the otherside of the belt. Water pump needs to be reversed. Oil pump would suck instead of blow. I would start with a different motor that is already the way you want tit __________________ If you spent the time to fix it.... Fix it better than it was!

12-13-2006, 06:21 PM	#10
Bense Moderator Join Date: Mar 2003 Location: Clemson, South Carolina! Posts: 9,217	Re: reversing engine rotation? (thesmogman) __________________ http://people.clemson.edu/~ABense

12-13-2006, 07:46 PM	#13
Bense Moderator Join Date: Mar 2003 Location: Clemson, South Carolina! Posts: 9,217	i think what they did was flip the cams around and put the head on backwards. It was some crazy euro team that wanted ram air __________________ http://people.clemson.edu/~ABense

12-13-2006, 10:40 PM	#14
rip94delsol Member Join Date: Jan 2006 Location: Shifting through socal with 3 toes Posts: 2,044	Re: (Bense) i get it.... wait no i dont....hold i know Im confused, thats what it is. thats alot of work. but what about the trany cant you just change the way the tranny moves the wheels... __________________ http://laskeyracing.com

12-13-2006, 10:52 PM	#15
Bense Moderator Join Date: Mar 2003 Location: Clemson, South Carolina! Posts: 9,217	I don't think that you'd want to reverse a tranny. __________________ http://people.clemson.edu/~ABense

12-14-2006, 09:48 AM	#16
thesmogman Member 1988 Honda CRX My Garage Join Date: Dec 2005 Location: San Ramon/Pleasanton, CA, USA Posts: 1,592	Re: (rip94delsol) That one was too early for me too. (headache) but whoa.. I, I, I, dumbfounded... .... damn. __________________ If you spent the time to fix it.... Fix it better than it was!

12-14-2006, 11:26 AM	#18
DonF Member Join Date: May 2002 Location: Atl. Beach, fl, duval Posts: 5,197	Re: (racerpat94) We converted B series 1.8 and 1.6 engines to clock rotation 10 yeare ago. You need custom cams, some work in the oil system, a dry sump oil pump, a little work in the water passages, a mugen "clockwise" water pump impeller or the one we made, plus a different belt tennsion ing system. We used a Tilton starter for a Posche and a custom starter bracket for it, I still have one of those lying around.

12-14-2006, 11:50 AM	#20
DonF Member Join Date: May 2002 Location: Atl. Beach, fl, duval Posts: 5,197	Re: (racerpat94) We did the first rear wheel drive Acura for GT3 in the SCCA. We also did Ralt and swift conversions for Formula Atlantic and CSR in SCCA using the B-16

12-14-2006, 12:16 PM	#21
d16dcoe45 Senior Member Join Date: Jul 2005 Location: Armonk, NY, USA Posts: 3,729	Re: (DonF) That was a BTCC 2.0 liter f20b or h22 right? I heard some teams would spin the head around for precisely the reason you said--to have the intake facing the front of the car--8500 rpm ceiling and over 300 hp--they must have been doing something right!! I think that b16 in the Formula Atlantic is awesome Don,--I had no idea you didn't have to use the 4age until you told me. The current claim--even in a Toyota ad from about 2 years ago was 255 hp (crank) at 1600cc. Were your b16s in that area? __________________ Cusco EF master cylinder brace-- brand new, unopened, still in package $75 shipped obo (RHD ONLY!!!) WTB: 88-89 Civic hatch driver side door w/ glass and regulator. Losi xxx4 G+ Associated Rc10 t4 FT Losi xxx BK2 JConcepts BJ4 WE

12-14-2006, 01:07 PM	#22
DonF Member Join Date: May 2002 Location: Atl. Beach, fl, duval Posts: 5,197	Re: (d16dcoe45) 248 crank. And about $12,000 cheaper.

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