New crank! Finally a knife edged crank to add to the set-up. On the left is the new set-up and the right is "old faithfull"... my old set-up.



I have been learning about engine acceleration and making changes to my previous set-up.

Weight savings: The old Crower Pro billet rods and wrist pins weigh 130 grams more than the Carrillo's on the left.

The crank weighs 8lbs less than the old one on the right.

Piston weights are just about the same, but the new is 90mm and the old is 89mm diameter.

I am hoping this engine will accelerate much faster than my old set-up, but I am not totally sure on the power output yet. I am shooting for 285whp in my Accord.

I will post the new assembly pictures as I make progress.



Modified by 2point6 at 5:23 PM 3/20/2007

 

subscribed.

 

god luck scott. Which 90mm piston did you go with? Can you explain the point of knife edging a crank other than shedding weight? Is it just an air resistance, more aerodynamic, type of deal or what?

 

At first I saw the thread title and was like here we go again, then I saw the creator and I was like nice.

Anyway I think you started to mix yourself up on the bottom. The knife edged crank is the one on the left. Also the carrillo's are on the left too right? I thought you said the left was the new setup.

Anyway looks nice, but are you at all worried about harmonics?

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">god luck scott. Which 90mm piston did you go with? Can you explain the point of knife edging a crank other than shedding weight? Is it just an air resistance, more aerodynamic, type of deal or what?</TD></TR></TABLE>

It's to reduce the rotational mass.

 

8 pounds and 130 grams off each rod/pin is going to help alot. couple that with a light flywheel and im sure your engine will rev very quick. Nice to see you going 90mm AGAIN

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">god luck scott. Which 90mm piston did you go with? Can you explain the point of knife edging a crank other than shedding weight? Is it just an air resistance, more aerodynamic, type of deal or what?</TD></TR></TABLE>

Pictured are my JE X forgings, but I have not decided if that is what I will be running in the end. I am actually looking for an even lighter piston design to complete the package.

As far as the Knife edging, I did it for the weight reduction.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94Vtecluder &raquo;</TD></TR><TR><TD CLASS="quote">At first I saw the thread title and was like here we go again, then I saw the creator and I was like nice.

Anyway I think you started to mix yourself up on the bottom. The knife edged crank is the one on the left. Also the carrillo's are on the left too right? I thought you said the left was the new setup.

Anyway looks nice, but are you at all worried about harmonics?

It's to reduce the rotational mass. </TD></TR></TABLE>

My mom always told me to hold out my hands and point up... the one hand that makes the "L" is the left. Damn... mom was always right. Yes, I made the mistake, I am a tard.


I am building this engine for race application moreso than a street engine. For a streetcar, I probably would maintain the stock counter weights. My last engine did really well, but I had always wished I had done lighter rotating parts from the get go. I didn't and about 70K miles was way more than I ever expected from the first set-up.

 

Hi Scott:

Looks good! The best of luck to you.

 

would there be any advantages to knife edging other than reducing rotational mass?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 98vtec &raquo;</TD></TR><TR><TD CLASS="quote">would there be any advantages to knife edging other than reducing rotational mass?</TD></TR></TABLE>

Aerodynamic improvements are made, but the recent trend is toward shaping the counter weights like an airfoil with the blunt end foreward tapering to the trailing edge.

 

nice, keep us updated. can i buy ur old setup?lol

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MacONE &raquo;</TD></TR><TR><TD CLASS="quote">nice, keep us updated. can i buy ur old setup?lol</TD></TR></TABLE>

It is availible... let me know if you are serious.

 

suscribed
nice comparison pics

awaiting assembly

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2point6 &raquo;</TD></TR><TR><TD CLASS="quote">My mom always told me to hold out my hands and point up... the one hand that makes the "L" is the left. Damn... mom was always right. Yes, I made the mistake, I am a tard.


I am building this engine for race application moreso than a street engine. For a streetcar, I probably would maintain the stock counter weights. My last engine did really well, but I had always wished I had done lighter rotating parts from the get go. I didn't and about 70K miles was way more than I ever expected from the first set-up.</TD></TR></TABLE>

Heh, I like the "L" idea. Anyway I would wonder how knifeedging would hold up in the long run. I would imagine Honda put the counterweights their for a reason ya know? Could be to keep the engine harmonics good, or who knows it might be there to keep the momentum going during the off-stroke. Let us know how it holds up, also you said this isn't your DD anymore but it will still be streetable right?

 

Heavier counterweights help to suppress harmonics in the crank.

There are two sides to every weight issue with cranks rods and pistons, lighter is better up, heavier is better down....

 

what is the stroke on that thing anyways?

 

it was 98mm

I believe this crank is a modded f23 crank, so 97mm

 

hmmn, they both look like f23 cranks...

 

Looks sweet. Good luck on getting to that goal, man.

 

are there any con's to these knife edging e.g. durability or longevity?
nice work looking forward to seeing how this turns out btw.

 

nice

 

What made you decide to go with 90mm bore over a 89mm bore? What types of reliability issues do you see with a 90mm bore?

Also, what do you say to all of the naysayers about knife edging the crank? Everybody here on H-T swears up and down that knife-edging shouldn't be done.

 

Heh, it looks like my crank.. And the same size Pistons I have also. Copy Cat! lol, Just messing. You'll probably have yours together before I do and I don't have a Shell to put it in either..

Cranks are knifed edged for many reasons, weight reduction and less rotating mass for a some.. Some V8 guys do it to their's also, they've been doing it. I talked to one that built race engines for cars back in Memphis and he said he had tried many different, eh well, "technique's" to modify the crank. From Knife Edging custom built ones. He had one in a car that was so light it was hard to turn it over.. They'd have to jump up and down on the back to help it turn over..


Actually, I have my engine mostly together, just it's not going into a car anytime soon, unless I fall into a shell and an extra bit of cash..
I'll see what you can pull out of it Scott, and when I can, bring my engine down there and have you drop it in for me and see what I can make..

or

 

sounds good

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by prelittlelude &raquo;</TD></TR><TR><TD CLASS="quote">8 pounds and 130 grams off each rod/pin is going to help alot. couple that with a light flywheel and im sure your engine will rev very quick. Nice to see you going 90mm AGAIN </TD></TR></TABLE>