Powerspeed Exhaust

[SPW]

I'll shortly be taking delivery of a new Powerspeed 4-2-1 exhaust system to fit to my 1.6k Superlight.  Will be doing the installation myself and have read some of the previous posts in the archives but any hints and tips from those that have done this would be appreciated.

In particular, does anyone have any photographs they could send me of the enlarged aperture for the primaries through the side skin as I want to keep this as small and neat as possible.

Thanks in anticipation.

Steve

 

[Paul Mason]

Have you read about the change needed to the alternator? The back plate needs to be turned through about 180 degrees so the connector plug is at about 7 o clock or it can foul no.1 primary and melt and then you car stops working and friendly people on a blat have to push start you.........

[StevehS3]

My top tips

- Loads of masking tape and cardboard to protect the paintwork if you slip

- I used a dress maker’s curve around the primaries to give a smooth line and even gap (honest it was my mum’s!)

 

[Alastair B]

Steve, you may have read my post about fitting, search power speed exhaust fitting from google doing a site search method. The one thing I found difficult I wrote up later after a friend helped me, that was fitting the collector to the primaries. The right way is copied here......

”Called in a friend, multiple Caterham owner and knows 4-2-1 systems well. His method worked a treat. Ensure no burrs by lightly emery the primaries lip edges. Aligned the primaries loose to get them to engage the collector. Then tightened the primary pipes securing nuts to create some resistance. Then by slowly holding the rear of the silencer articulate in a series of small up/down/side to side motions whilst pushing reasonably hard from the rear, the silencer 'crawls' forward onto the primaries...only took 10 minutes if that. Very appreciative of his help.

i will post a picture of the side skin hole tomorrow

[rj]

Don't make the hole to narrow or engine movement will damage the sideskin. And don't ask me why I know :-p

[CheshireCat]

When I fitted my powerspeed I had to enlarge my hole in the side skin backwards. The curve at the front was determined by my original hole. 

[SPW]

Many thanks for the replies, much appreciated. 

RJ - How much clearance around the primaries do you recommend to allow for engine movement?

Steve

[rj]

More than 4mm

I'd say at least 6-7mm

[StevehS3]

I agree with RJ about the clearance. I think the engine mounts can sag over time so make sure the engine is where it should be before cutting the hole. Is the existing exhaust in the middle of the existing hole or towards the bottom (indicating is has sagged)?

[Alastair B]

My cut out...preferred the curves joined by a straight line to keep a simpler shape

[CheshireCat]

Looks like the primaries require different shaped holes in the side-skin. 

[SM25T]

All different ... depending on the shape and layout of the primaries. Start with one through your existing hole and work from there one at a time ... trying each new primary through the same hole. Work out the order they bolt to the head first and label them.

[p.mole1]

Take your time,I used a hand file and started with number 1 primary,  

[rj]

 I did something similar to what p.mole1 did although I used something like this (dunno the English name of it)

to do the final finish. If the car is paited it can form a problem as it may leave a "glory" around the hole as it wears down.

(My car is unpainted for weight saving)

My cut was similar tight to p.mole1s, but abuse has proven that it will be less tight over time :-o

 

[Jonathan Kay]

That image doesn't show for me.

Jonathan

[rj]

Better now?

[Jonathan Kay]

"Flap wheel"!

Jonathan

[rj]

Thanks, and when you tell me I know I've heard it before. It's even not far from the Danish name.

 

[SPW]

Thanks for the photos and tips.  As stated they are all a little different.  

Current exhaust is slightly "low" in the existing round aperture so there could be a little sag in the engine mounts so may be worth taking the opportunity to fit new ones.

When fitting I assume just nip up each primary on to a new gasket when taking them on and off to cut the hole and only torque up fully when everything is right and the collector is fitted. I'm assuming there is not much movement when finally torqued up?

Steve

[David Brown]

Seem to remember that I had a problem with clearance when trying to remove it which I suppose must have been the starter (it was a number of years ago).  I should probably have made the hole a bit bigger. 

[Alastair B]

To check position for cutting one at a time you do need to tighten down the nuts, I did this without the gasket being present. When torqued down they are rock solid. As previously said do one at a time and take your time, you will be amazed how much material you have to remove. I used a drill powered nibbles to take progressive crescents of material away and then used round file with a pushing cutting stroke and then finished with emery paper. 

[SPW]

Well it was all going so well, skin cut out to take primaries ready to fit the collector and can. However, on assembling things together loosely the mounting brackets on the exhaust don't line up with those on the car! Firstly the pitch between the brackets on the exhaust and those on the car are out by about 10 mm lengthwise, not unsolvable with some fettling but annoying.

More significantly though the rear mounting point is about 30 mm out of alignment, with the can sitting parallel to the side skin (with a clearance of about 20 mm) the rear pick up point has a gap of about 30 mm outboard, the front one also has a gap but is much less.  Even the exhaust was forced to fit by pushing it towards the centreline of the car the can would foul the side skin before the mounting points aligned.  The easiest solution I can think of is to make up a new rear mounting bracket for the car with but about 50 mm longer to pick up the exhaust bracket correctly.  My only concern in doing this is the bracket section bolted to the car is only short being mounted off the chassis rail so extending the length of the outboard section will place more stress on this connection point due to the increased leverage, but maybe I'm being too cautious.  The other option is getting the can back to Powerspeed to do a change to the bracket by putting a welded extension piece on it but that would be a pain due to the distance involved an time.

Did anyone have any problems with alignment of the brackets and if so how did you get round it?

Thanks

Steve

[SM25T]

Wonder if the alignment of the engine and gearbox is not true ... a few mm at the head would be greatly magnified at the rear exhaust mount. I had PowerSpeed build and fit mine at their works.

[SPW]

It's possible but the fact that the can will foul the side skin and the mounting points still don't align leads me to think it's either the brackets on the car or on the exhaust.

[Alastair B]

I think you should try and assemble not loosely i.e try and see for real where it all is when the collectors are torqued down to the head and the can installed. This will give you the real situation and then the fix, if you need one will be more precise and easy to figure out.