Hi Guys,


Apologies if this has already been discussed. Could not find a similar topic with answers.

Have come across a problem where I will need to change the crankshaft in my fully built B18C motor running MID Sleeves and 85mm CP pistons coupled with Eagle Rods.

My problem is that this is the 2nd time a bearing has spun on the crank the 1st time was when I had the standard pistons.

I have a Golden Eagle Knife Edge Crank lying with me which was for a B16a in perfect condition. I have only 2 options use the b16 crank or order another crank which will cost a lot of $$$(for used crank + shipping) and take time to reach me here in India as well.

Also can anyone tell me how much power would I loose if i swapped crank or what differences would I face. I know the stroke is different but what does that translate to in driving terms.

What should I do?????????? Pls help

Thanks in advance.

Jignesh

 

besides needing custom rods, (obviously the motor is now a tall deck b16)

 

Hi,

What I am asking is can I use my existing Eagle Rods on the knife edge crank and if I do what will happen.

Jignesh

 

You would be defeating the purpose of a B18C by using short stroked B16 crank.

 

Hi,

That still does not answer my question. I am not very technical so pls forgive my noobiness.

Let me put it this way:

1> Suppose I was making 250whp with the B18C crank earlier what would I make with the B16 crank all else remaining the same.

2> How much of a difference would it make in my qtr mile timing(approximate figures)

I just wanna know what I would be sacrificing if I install the B16 crank as I save time and money both.

Jignesh

 

There is roughly 10mm stroke difference in those cranks. It would drop the compression too low, not worth doing in my opinion.

 

Hi,

Well actually it may work in my favour. In the current setup I have 310 compression which is a little too high for me and I was planning on using double gaskets to bring it to about 260-270.

If the difference in compression would be approx that much then I have nothing to worry about.

Am I correct or is there something else I should be thinking about

Jignesh

 

the difference will be more than that

too much to the point that.. u might end up making less power than an unsleeved b16

 

You'll be way in the hole, Mandingo style.

 

About .43 inches I think. So almost half an inch. Your compression would be like 5:1. You could run like 100 lbs of boost lol.

 

Sell the knife edged B16 crank and get a good B18 crank, you do NOT want to run a B16 crank in your B18C!

 

run B16B lenght rods and your CR will probably end up near where you want it to be. Using the B18c rods are way too short.

 

He said its a golden eagle crank so perhaps its not the stock b16 stroke

Doesn't sound like he knows either tho

 

It wouldn't surprise me, considering someone asking what would happen if they used a B16 crank in their B18C.

C'Mon, Man....pull your head out of your *** and THINK!

I've read other threads of you talking about building these big-*** expensive builds, and you ask a question like THIS? Do you have 0 understanding of engines, or 0 understanding of basic geometry, too?

Makes me want to say "Put the wrenches down and STEP AWAY from the car!"

 

Sell the B16 crank, buy a B18C crank and stop being a dumb ***. End of discussion.

 

As mentioned,it will not work, your power will drop alot and it just wouldnt be good at all, the only way to make it work is to get custom rods..

How bad is the damage on the crank? You could maybe fix it up and run oversized bearings.

 

All of you guys need to stop telling him it won't work untill you know the stroke of the crank he has

Its is not a stock b16 crank, so stop talking to the guy like it is.

And c rock I completely agree.

 

lulz fckn H-T.

 

Get a new crank. Grinding down damaged crank journals and running oversized bearings works ok on older domestics.

On Hondas you grind away all the hardened material on the journals leaving them very soft. Those types of repaired cranks never last very long.

I speak from first hand poor highschool kid who couldnt afford anything else experience.

 

Hi Guys,

Thanks for all the answers and advice. Now for some clarifications.

1> I am not technically qualified. All the work is being done by engine builders/mechanics here in Bombay who hardly have any expensive working on high powered applications. They are used to work on small engines with just basic mods. These engines/cars were never sold here hence we do not have the required knowledge on the various differences between models.

2> I do not know 100% which cranks are there. I will measure them both and give the sizes to you experts to then guide me.

3> I was not installing the B16 crank just wanted to educate myself with the basic info as I had one spare with me which would save time and money.


I had mentioned I am a noob. If you read post no 5 it states that so save the sarcasm for someone else. If I had the knowledge I would not be asking for help

Jignesh

 

If it is standard B16 stroke then you could use B16B rods but this will depend on the width of the big end journals. The B16A big ends are .935" wide so B16B rods will not work as they are only .858" wide, same as the B18C.

Check the width of the big ends, if you've got .858" then you'd be in luck and if you can source some B16B rods then it will run albeit with a lower compression than you have curently.

Based purey on the change of geometry alone, if you have 170lbft now you'll probably end up dropping back to about 130lbft, but that's based on equal 100% VE and the numbers I have here suggests the B16 breathes a bit more effeciently than the B18C so it's hard to tell exactly how much you'll loose. At 85mm x 77.4mm you've got a 1.8 though so expect somewhere in the ballpark of B18 torque levels with a B16 power delivery (i.e. high up).

 

If your engine builder doesn't understand the drawbacks to using a B16 crank (or engine function/design, in general), then you should probably use a different engine builder.

 

I'm guessing you've never been to India...

 

Ship your motor to someone competent

 

Que Eff Tee

This is also the reason many builders hate dealing with the general public. Not only do they not know sh*t, they're too ignorant to recognize how LITTLE they know!