I spoke with Cosworth this morning. It does not look like any new Cosworth plenums will be coming out until November , after their re-tooling is complete and they are back up and running with production. It sounded like there will be some slight modifications to the way the end caps are sealed, but the endcaps still will be carbon fiber.

 

Thanks for the update.

 

wonder if they will make it so it can clear the
aftermarket fuel rails with out having to buy a lower plenum spacer

 

Some clever person needs to cast some larger end caps in aluminum and market it to the FI crowd.

 

Why? The Carbon Fiber end-caps have already held over 1,000whp...

 

+1

 

If Cosworth had made the end caps aluminum, I bet there would be a lot more of them right now on customer cars and they would have been less expensive to boot. I personally was hoping for different end cap options. That is an advantage of the 2 piece design. I really thought they would have 1 for NA, 1 for FI. Oh well.

Besides holding and not leaking are 2 different things. I've seen the pic of the manifold from IP with the end caps blown off.

 

I agree with the different end caps..

 

I asked the guy at Cosworth whether we can get an option with aluminum end caps. He replied that there was not enough market demand to justify them spending the money on the development and molds for aluminum endcaps.

He also stated that the Cosworth plenum was intended for "naturally aspirated motors" and to run boost through the plenum was "at your own risk", although he said they should be good to 35 psi. I told him that I thought they were tested to 100 psi, but he didn't think so. He did say, however, that part of the re-tooling was focussing on a better seal for the end caps.

He also said that, in thier opinion, injecting methonal in the throttle body before the plenum was a bad idea. He said that they were concerned that it might pool in the plenum and ignite if there were any type of backfire. I am now investigating whether there is room to add meth injectors into the stock intake runners, below the plenum. As soon as I find out I'll let everyone know.

 

It may be hit or miss. Injected performance just blew theirs, but of course it was over 1,000 hp and they were running 36 psi. (Funny how Cosworth now says they should be good to 35 psi ). I don't think Luie was running over 1,000 hp, and he had problems with his cosworth. Others pushing very high hp have not, however, so it may be luck of the draw.

 

Well the instructions for the plenum state it provides gains for N/A and F/I vehicles, so Cosworth intended users to run it N/A and F/I, although high boost is obviously an issue. I am unaware of any official statement from Cosworth that if you run boost, you do so at your own risk.

I think it should be able to hold the 10 psi I'll be running just fine. For most applications it should be ok.

 

I have not seen the instructions (becuase I have not received my stinkin plenum yet ), but I don't think the guy that I spoke to on the phone was aware of that. I wish I had those instructions in front of me when I spoke with him. I would have loved to have pointed that out to him right after he told me the plenum was intended for N/A.

To put in the instructions that the plenums are intended both for N/A and F/I applications, and then to have their in-house technical staff contradict this is very unfortunate. But they are Cosworth. In the overall scheme of things, it really does not amount to a hill of beans to them. That's just the way it is.

It appears that there have been enough issues or unsatisfied customers to spur them to make some manufacturing changes, but let's face it, how many people buying the plenum are really going to use it for any serious amount of boost. It's probably easier for them to handle the individual problems on a case by case basis as they pop up.

That said, in my opinion, they are handling this entirely incorrectly. They are a very reptable company. All they need to say is that they had an unexpected problem, and that they are revising the design to address it. Unfortunately, that's not what they are doing.

Nonetheless, it probably doesn't matter, because I, as well as countless others, are still lining up to buy that plenum because there is nothing else out there (at least that I am aware of) that provides as good performance for high boost applications. In the end, I'll buy two plenums and take my risk. If one blows, I'll send it back for repair and put the spare on. Sad, but true.

If anyone else can provide equivalent performance for high boost applications, now is your golden opportunity to get in here. You have at least two months to prove your product, and you will have us VQ guys beating your door down to by your product.

Motordyne Tony, are you listening to this?

 

Also stated on Cosworth USA's website:

"the Cosworth Twin Plenum Inlet manifold is perfect for both normally aspirated and forced induction applications. Performance increases will be significant on engines with improved exhaust and intake system including optimized ignition/fuel maps with increased maximum rpm limiter."

http://www.cosworthusa.com/store/pc/...2&idproduct=89

The MSRP has also increased.

 

i dont know about an equivalent, but there is something better for high boost applications hitting the market soon

 

Can't wait Charles - I'm hoping you provide a version for mid boost apps with a lower plenum spacer to lengthen runner length to the max that will fit under the stock hood.

 

Charles,

Are you going to have a casting made of ypur manifold, or is it still going to be a billet piece?

 

He mentioned in another thread that the casting was in progress...

 

I can't wait. How soon?

 

^^^ Not soon enough!

Charles, I want for my 8k rpm redline!

 

What that....!! Cosworth for sale

First the twin pump now this...my wallet is showing signs of cracks ....CHARLES !!!