To start I did search for a little and didnt find jack.

My question is , which bearings are better ACL or Cosworth? I'm shooting for 600WHP.

I spun 2 mains on my old block and those were ACL bearings.

Should I stick to ACL or pay almost double the price and get Cosworth ?

 

Wow 120 views and 1 vote not including my vote , damn ....

 

I believe Cosworth has phased out all their VQ35 products.

 

I can still order bearings tho, I think IPP has them in stock

 

where the acl bearings that you spun their race series ones? or just regular?

 

Race bearings, do they have regular?

 

i thought they did, but maybe i am thinking of coated vs uncoated instead.

 

I really don't know but I feel confident in saying that the root cause of bearing failures is going to be a "simple" lack of lubrication, rather than part selection.
Was it you that started the thread about bearing clearances recently? That's probably a factor along with oil pump pressure and maybe even the lube hole size in the journal.
I'd love to hear conclusive evidence that "Cosworth never fails" but I'd be doubtful.

 

I'm not an engine builder but I'd agree with DJ. I think they are probably both fine products... My invoice stated Cosworth bearings fwiw, now nearing 30k miles.

EDIT: Not sure this is of help, but it was in my past readings. Good luck!

http://www.spridgetguru.com/TA0027_f...aringsFail.pdf

 

for some reason, i think the machine shop that coated my crank also elongated the oil passage holes on the crank for the bearings to get better lubrication. i think they did anyway. either way, i went with coated acl race bearings, but i only have about 1000 miles on my new engine.

voted acl here

 

I didnt create that thread but I posted in it a few times.

I know at least 3 STIs that spun cosworth bearings within 4k miles, I just dont know if they are worth the extra money or not.

will read that when I get some time at work

I made 7k miles on my ACL bearings , thats with a really bad tune 18:1 A/f, red line runs... surprised it lasted as long as it did. This includes 2hrs of stop and go traffic every day which is around 3.5k miles of the total 7k.

 

I went with cosworth, I like high end **** I have heard good things about both. I would go with the others and say most bearing "issues" are not bearing failures but other contributing factors.

 

I have spun them all

ACL, Cosworth and Nissan stock... the bearings themselves aren't the issue IMO, its the clearances and assembly.

 

^Poor cass, eh!
When you consider that the part was designed for trillions of cycles, if it fails after a few months, something else must be at play unless they have a bad QC program that fails to identify their faulty product. Maybe their web site outlines something that makes you feel better.
For example, have you been to ARP's site? Their explanations are amazing, detailed and impressive! I personally think that their L19's are overkill for all but the most extreme builds, but I have no doubt that those studs are far superior after looking into it. They have put the time in to try and justify the substantial premium that you pay for their best parts and I respect that.

 

Troof

Worry more about who machines and builds the engine. If it's 100% proper the bearings won't matter. for fack's sake it's just a strip of metal and oil [is supposed to] bear the load...

great link rcdash!