Picking right size rods, pistons, bearings (help)
 

I need help picking out the right size rods, pistons, and bearings for my engine rebuild for my 2006 Evo IX. I've had the block inspected and I can use the stock bore which is 85mm for the pistons, so that is good. I want to use all BC listed parts except bearings obviously.

So which parts do I need? Please look at these pages and suggest part#'s for me. I am using the stock crank.

Link to rods: http://briancrower.com/makes/mitsubi...vo9_rods.shtml

Link to pistons: http://briancrower.com/makes/mitsubi..._pistons.shtml

And then which ACL bearing would work with your suggested setup? Sorry if this is a total newb thing but I don't know what I'm doing and I need help. :helpme:

Thank you.

Before you continue, tread carefully. Understand that to build this engine properly you could probably just have Dave Buschur - or others; build you a motor for the same price. You will want a bunch of machinist measuring tools to insure you're not putting together a grenade. Machine shops make mistakes, they are human like everyone else.

There is more to it than just assembly. There will be machine, and balancing work that will be absolutely necessary for this to be a successful venture for you.

That being said, It depends on what you are deciding to do with the motor. If you are keeping it 2.0l you can do two things.

1. Long rods, short ("Stroker") pistons. You will need to combine stroker pistons with 156mm (Long) rods. Benefits are higher RPM capabilities and better rod ratio.

2. Standard rods (150mm), standard pistons. This is a proven setup and some of the fastest evo's in the world did it on the standard setup.

Once you decide on the setup, you must balance each piston and rod to a close tolerance so that your new setup won't shake itself apart.

Even if you decide to go with stock bore pistons, you will need to have your block honed. It's strongly recommended to go with an increased piston to wall clearance with forged pistons as they expand differently than the stock units. Additionally with increased power comes increased heat and pressure further extending the need for increased clearance. Hopefully your machine shop has a torque plate so your cylinders are honed correctly!

Rod + Main bearing choices are dependent on many factors. What power are you shooting for? Is your crank damaged?

When you choose your bearings, you pick a base size to start with. Your machine shop will turn/polish the crank after the balancing process to create the proper clearances after you measure the inside bearing diameters.

Additionally, you're probably going to want to go with main studs, which means that an align hone may be necessary as well (Increased torque distorts the block)

Good luck on the venture. Judging by your post, I would suggest buying a book or having a professional do it. Unlike anything else on your car, the measurements, torque specs, and procedures when building a motor must be followed to a T. Otherwise you will be throwing $1000's of dollars down the drain when the car blows up.

Oh, and as far as engine bearing clearances - do your best and search. Every set up is different, and no vendor likes dishing out their specs they invested in trying over the years.

PS: Don't waste your time on H-beam rods. IMO, the stock units are just as strong. I'm not a fan of Brian Crower BTW. I run Crower rods (Different company than Brian Crower) and Wiseco HD pistons)

^^^ that and I also recommend staying away from BC products.

x2

I'd look into wiesco hd pistons and manley turbo tuff rods..If those rods are too much you can go with eagle's, which have been proven over and over..

This is Dustin from Brian Crower. I will be the first to admit we had some issues when we first started BC. Back in 2006 we had some growing pains as we actually grew too fast and had to contact some products out to other shops while we expanded and some of the QC wasn't what it should have been. Any issues we had was years ago and have been corrected and we made the appropiate employee changed. We stand behind our products 100% and if anyone has any questions or concerns my direct line is 619-749-9018 or my email is dustin@briancrower.com

Start with what you want to do with the car, and how much power you want to make.

I like BC's products personally. I have their 272 cams, +1 valves, springs, retainers. I also used them on my WRX.

But tell me more about this balancing thing. Do I have to balance it or can I just hone the cylinder walls, slap it together, and be on my way? B/c i read on inline fours balancing isn't as important as it is on V's or boxers and that you can actually install it as-is and it runs just fine. One guy even took out his balancing shafts and it was still good.

I am sure i have seen this posted somewhere else on the forum before?

Maybe a couple of times?

uh oh.. duplicate content makes google spiders sad :*(

http://cf.sketchfu.com/i/25085.png

lol

Since you are in Florida, drive your car to AWD motorsports and have them do your car. You are asking a lot of questions and would be very cautious when building an engine. I have built engines before but when it came to building my engine for my Evo I was on the phone with Wiseco techs talking to them about clearances and specs for my set up. You are also losing hp with the BC cams, through some Cosworth M2 or M3 or GSC S2 or S3s and you will be happy.

Also, depending on your budget, get some Manley Turbo Tuff I-Beams and stay away from BC. These rods are the last rods you will need and have supported well over 1000awhp and 8 second passes. Build your engine right once and you won't have to worry about it ever again.

PS, you can install everything without balancing, if you want to take it apart again sooner or later. It is 10 times better to balance the whole rotational assembly if you have the opportunity to do it. If you are just doing a drop in set up, try to balance the rods and pistons as close as possible and drop them in. The better balanced your engine, the less vibrations you will have and it won't "shake" anything loose.

To do it right everything must be balanced, even your clutch. Anything that rotates, except your cams. Or you will have harmonics that will tear you engine apart. You have not even mentioned the head, just have it built by some one who knows what they are doing. As mentioned before even when reputable shops build motor there can still be problems from time to time. You have no clue what you are doing and will just be wasting money and time.