Cosworth Stage 2 Install w/Dyno, Pics, Videos, Impressions

[350matt]

I think there's plenty of headroom in the blower as theoretically its good for about 350-380Bhp

its a question of when the stock rod will bend under the pressure
I'd have said if Cosworth thought the stock bottom end was good for more, then they would have supplied the kit with smaller pulleys and more boost

aren't they supposed to be releasing a 'stage 3' kit to capitalise on the blower headroom?

I'm assuming that this will be a small pulley set, although the install I've seen looked like the SC pulley couldn't go much smaller?

So would they have to change all the pulleys do we think?

[ajc209]

Matt - the current belt is not wide enough to reliably drive the sc any faster. They will need to release a pulley set and new belt.....

Stage 3, I am told, is targeted for summer release. It is looking like it will be a bottom end and new pulleys for 325hp initially.

Personally I'd be a bit concerned about low oil pressure when things get hot, for more than stage 2. Stage 3 might be new bearings though....

[350matt]

OK that's going to be all of the pullies including the AC and the crank then?

should look good
interesting that the edelbrock and harrop blowers are still using the 6 rib belt then? as they are bigger blowers you'd think they would also need a bigger / wider belt

or are Cosworth being too conservative?

[ajc209]

Or the others might be under engineering it. The larger pulley is just what I have heard from one of the uk distributors, but was direct from Cosworth aparently. It makes sense that you wouldn't make it too easy to upgrade the pulley to make more power without their bottom end stage 3.....

The thing is, Cosworth will be able to do clever things like finite element analysis to determine the strength of the bottom end. They might find that the rods can do 100 billion stress rotations before wthe rods bend or break, or it might be 100 thousand. The fact that they can do that puts them at the top of my list.

The same sort of thing is true of belts. Cosworth engineers will make damn sure if never slips or breaks for a resonable amount of miles. Is there a belt change interval come to think of it?

[350matt]

Only trouble with that is on 1st glance it will make the 'upgrade' seem expensive as a pulley for a Kraftwerks or Sprintex is about $150 whereas a complete set of pulleys will be what a $1000?

I wonder if Cosworth are going to subscribe to the same view of the rest of the tuning industry and delete the crank damper with their new pulley?

cue a bunch of comments about how its not neccesery and OEM's only fit them for a laugh.......

[ajc209]

I've already been shot down when suggesting a possible reason a bearing went on low milage car was because of the lightweight pulley fitted to he crank....

At least if Cosworth do it, I trust that it is safe. My main beef with most tuners is the lack of actual engineering skills. Instead they try it a few times on the dyno or drive 1k on the road and start selling it as a safe upgrade without proper consideration of engineering tolerances.

[weederr33]

A $1000 crank pulley from Cosworth? I could see that

I figured their Stage 3 would include larger injectors, and forged internals with a smaller pulley?

[ajc209]

I reckon stage 3.1 for 325hp will be bottom end and pulleys/belt and for stage 3.2 375hp could be bigger injectors and a pulley.

[350matt]

Originally Posted by weederr33

A $1000 crank pulley from Cosworth? I could see that

I figured their Stage 3 would include larger injectors, and forged internals with a smaller pulley?

I meant that you'll get a complete set of pullies , as if they go to an 8 rib belt everything will have to be replaced, inc the AC pulley

I suppose if you need bigger injectors then they'll include them in the kit?

what would we expect to pay for the SC upgrade kit then? assuming that their bottom end costs about the same as everyone else?

I was thinking pullies + injectors + bottom end / short block is what would be required to make a reliable 380Bhp
possibly an intake? as I think Cosowrth mentioned the stock intake was starting to choke about 300bhp?

[ajc209]

IIRC they said the stock airbox was okay up to about 350hp... so might be a new airbox included in stage 3 to get 375hp.

Id expect a bottom end (depending on what actually gets changed) and pulleys/belt ~ £3.5k + cost of someone fitting it all....

[350matt]

are there any aftermarket intakes that actually do anything?

[weederr33]

Originally Posted by 350matt

are there any aftermarket intakes that actually do anything?

Supposedly Grimmspeed

[ajc209]

Most of the intakes mess with the maf calibration to gain a few hp. I am not aware of any that improve flow. I think most of the high hp turbos have a cone filter in place of the stock airbox....

[ajc209]

The grimspeed looks like an injen copy to me..... to actually improve flow at 350+ hp id expect the pipe diameter to made larger. I'm not an expert though.....