federal stiffy anyone?

[bratboy_y2k]

hey folks, i was just talking to a friend at the local bmw dealership. guess what he builds in his spare time...yes thats right, exhaust bits. i guess he has to be able to since he just twin turboed a v8 beemer. he did the work on the intake and exhaust. i spoke to him about doing a batch of stuffys and he said forsure but wants to get an idea of how many. how many people are interested? he will also do ehaust manifolds if anybody is interested.

[lotos]

Sure, why not?

1) lotos

[esprit888]

Sure, why not?

1) lotos
2)esprit888

[tweetdriver63]

I know I'm going to sound like an idiot, but what is this bit for, exactly?

[lotos]

Connects your turbo to your exhaust, removing the restrictive factory pieces.

Technically, the "stiffy" is a combination PCE and turbo exhaust manifold all-in-one piece. The PCE is only a replacement for the pre-cat and doesn't include the turbo manifold - it bolts to the bottom of it.

[Doc Fizzix]

I think nitroman's pre-CAT eliminator does away with the need for a "stiffy"

[lotos]

I don't think those are available though.

[tweetdriver63]

Sure, why not?

1) lotos
2)esprit888
3)tweetdriver63 (what sort of price?)

[esprit888]

Thats what i thought too, if a PCE is available i would take one today

I think nitroman's pre-CAT eliminator does away with the need for a "stiffy"

[nitroman]

Thats what i thought too, if a PCE is available i would take one today

I think nitroman's pre-CAT eliminator does away with the need for a "stiffy"

The PCE is available for $160 by contacting Stan's Headers directly.

[Enright]

They're also £92 from Piper, which at the present exchange rate must be pretty competitive.

http://www.pipercams.co.uk/exhaustshop/ ... ts_id=4440

[esprit888]

As crazy as it sounds i believe you are right ! It would be cheaper to buy the Piper PCE and air mail it from the UK to the west coast of Canada (at a rate of 1.78 $CDN to 1GBP = Approx $213 CDN including shipping) than it would be to buy it from Stans in Seattle (just an hour down interstate 5) at 0.76 $US to 1 $CDN (approx $245 CDN including shipping) Hmmmm, what else do i need over the pond

They're also £92 from Piper, which at the present exchange rate must be pretty competitive.

http://www.pipercams.co.uk/exhaustshop/ ... ts_id=4440

[lotos]

Maybe we could do a group buy and Stan would cut us a good deal...

[nitroman]

Maybe we could do a group buy and Stan would cut us a good deal...

FYI the last group-buy was $125 with a minimun order of ten.

[lotos]

So.. a stiffy replaces both Pre-cat and downpipe, right? So this is technically better than a PCE (Piper, Stan's, etc) ?

[Doc Fizzix]

So.. a stiffy replaces both Pre-cat and downpipe, right? So this is technically better than a PCE (Piper, Stan's, etc) ?

Depends on flow, how is the flow through the cast stock pipe and then PCE compared to the flow through a "stiffy". The answer will really depend on the overall workmanship and flow testing of the "stiffy", I originally think the purpose of the "stiffy" was that it eliminated the pre-CAT since Stan's pipe was not available, but now that Stan's PCE is available again I think the Nitroman's (Stan's) PCE is the best way to go.

[dapinky]

My understanding is that the stiffy was designed with the purpose of eliminating the Pre-cat (as that is the greatest restriction), and it was designed to incorporate a pretty-looking tubular wastegate manifold, so that the whole thing looked more 'integrated' when installed between the turbo wastegate and the stainless front pipe, as well as giving a respectable weight saving.

Due to the tight spaces involved, and the small radius bends, it was/is quite a feat of engineering to produce, and i take my hat off to the original designer.

However, when the PCE came along and just replaced the cast iron dustbin, leaving the iron wastegate manifold, it was a far simpler (and therefore cheaper to produce) item.

It doesn't look quite as sexy, and there is less (but still significant) weight loss......

....however, it actually gives better gas flow than the stiffy (under top boost conditions).

Without going into the theories of thermal and fluid dynamics, it all comes down to the routing of the gas once it has gone through the wastegate (so obviously, only comes into play when the wastegate is open, ie under heavy boost!).
The original cast iron wastegate manifold has a seperate channel casting for the main exhaust flow and the wastegate flow, which merge a short distance down the pipe, before all entering the pre-cat in one lump, the stiffy merges the flow a lot further up (at the flange).

Now, there is a theoretical way to ensure that the 2 channels merge at the optimum point, but every case is different, and it just so happens that the Lotus engineers got it right with the original design (or at least, as right as they could with the space availlable!).

In an ideal world, the 2 channels would actually be 2 seperate round pipes, with lovely smooth radii, merging about 140mm from the wastegate, and then passing into a single round pipe over a distance of about 50mm. Clearly that is not possible with any road car, unless there is a hell of a lot of space availlable, so we go with the easiest compromise.

Actually, the difference between what we have, and the perfect set-up is not huge, so on a road car is somewhat irellevant - and the difference between a stiffy and a PCE is (likewise) not huge.

Personally, i love the look of the stiffy, but i like the gains given by a PCE, i am prepared to accept that the extra weight is more than made up for in the potential for extra power release, and the cost and availlability make it a no-brainer to me

[lotos]

Geez - you ask a question and get a complete reasoned reply. Is this a web forum or a cotillion? I appreciate it!

[esprit888]

Well i told my wife i was getting a federal stiffy and she's never been the same since ! , so now what do i do ? Is a Fed stiffy available anywhere right now? (my wife wants to know)

It doesn't look quite as sexy, and there is less (but still significant) weight loss......

....however, it actually gives better gas flow than the stiffy (under top boost conditions).

Actually, the difference between what we have, and the perfect set-up is not huge, so on a road car is somewhat irellevant - and the difference between a stiffy and a PCE is (likewise) not huge.

Personally, i love the look of the stiffy, but i like the gains given by a PCE, i am prepared to accept that the extra weight is more than made up for in the potential for extra power release, and the cost and availlability make it a no-brainer to me

[PiperRS]

I am happy to look at different carriers to see if i have a way of sending a batch of our PCEs to the US if a few of you wanted to organise a group purchase.

As they would all be going out of the EU you would not pay Vat either so that helps. The unit cost would be £80.00 then