What about this? - replacement/upgrade options

[Guest]

Hi people of BC! I know this is a well discussed topic but I've done a lot of reading so you can lower your weapons Just wanted some more specific advice.

 

My car is a 1.6 K and competed in the mega-grad series. The engine underwent a rebuild by McMillan, and having had a chat with them, the engine would have been upgraded to produce circa 140bhp comprising the Supersport upgrade (cams, ECU remap), VVC inlet, 52mm TB, solid lifters & forges pistons.

 

I'm reluctant to throw any more money at the engine it's self, bearing in mind this is my first seven and will want something bigger in the not too distant future. However, the existing exhaust silencer has a nasty rattle to it (loose baffels probably?) and is becoming increasingly annoying. With very limited seven knowledge I don't know for sure what exhaust is fitted, but I *think* it is probably the original Caterham exhaust that came with the car from new with a 4-1 collector internal to the engine bay. If anyone can confirm this from the pic below it would be appreciated?

http://i75.photobucket.com/albums/i315/pullpete/20140322_1524542.jpg

 

So, assuming it is the standard exhaust as fitted to the 120bhp k-series, and given that it has the annoying rattle, I really see no option other than to UPGRADE!!!

 

So after doing some reading, it seems like the consensus is that you can get more BHP and a better breathing engine with a system comprising an external 4-1 collector, or better still, an external 4-2-1 collector. So I really just wanted to get a steer from you highly knowledgeable folks as to what my options are, and the associated benefits. It seems that at the dog's danglies end of the spectrum I could get a custom job at Powerspeed, but at £1000+VAT it is a bit more than I'd ideally like to spend. More than happy to spend half that. I'm also told that the job of cutting a larger hole in the side panel is not for the faint hearted (as a DIY job), so need to weigh up the benefits against that.

 

Another possible option (perhaps??) is this I've just found in the For Sale section:

here

Could I potentially get this silencer, cut off the old one and have a fabricator fit this one to my existing manifold/front section? I guess this would solve the rattling in the first instance; I don't suppose it would gain much performance, if any? I could then maybe look at getting some 4-1 or 4-2-1 preliminaries and collector made up to meet the new silencer at a later date. It is stated though that this silencer is without a CAT so presumably it would need to be interchangeable with the original silencer come MOT time?

 

Thoughts and advice very welcome and much appreciated

 

Edited by - Smiffy7 on 8 Apr 2014 23:25:57

[Bob L]

Ahh a rattle, this could be just about anything anywhere but check for the easy obvious bits first (I never do or learn from this experience!). My original rattle was a loose Lambda sensor. So simple to check – give it a wobble

[Silver Machine]

As you describe matters my supper sport has the same exhaust and did have a rattle. Could never work out what was rattling. On a visit to Dave Andrews it was identified that a worn but not failed bobbin had caused the connection of the 4 into 1 piece of exhaust to be a little loose. Dave's expertise, a new bobbin, silicon sealant and a bit of force sorted the problem out in my case.

[Guest]

I had a look over the exhaust again last night and checked the above mentioned parts and everything seems solid. The previous owner had it diagnosed as a rattle in the silencer, and it sounds like it coming from it pretty clearly, so I'm 99% sure it's that. It seems to resonate at it's worse when on the overrun at high revs.

 

So other than Powerspeed and Caterham Parts, where else do Caterham owners go for new exhaust upgrades? Not seen anywhere else mentioned in my previous research...

 

Edited by - Smiffy7 on 3 Apr 2014 09:55:54

[nickh7]

I have a 4 into 1 collector http://caterhamparts.co.uk/img/p/3626-3600-large.jpg if you want to buy one

[shn7]

Have you checked it's not one of the heat shield jubilee clips that's rattling? They sometime break but stay in place and the broken end(s) rattle at resonant frequencies.

[Guest]

Quoting Steve Newman: 

Have you checked it's not one of the heat shield jubilee clips that's rattling? They sometime break but stay in place and the broken end(s) rattle at resonant frequencies.

 

Checked the jubilees and although pretty rusty all were solid. I'm guessing this would only leave the silencer internals?

 

I did a bit of ringing around yesterday and can report the following:

 

Exhausts by Design:

£650 - Custom built 4-2-1 primaries mated to a Techcraft (or similar) customer supplied silencer (Not had a chance to source prices from Techcraft)

+£250 for a custom built silencer

This could include the option of fabricating a collector/adaptor for my old silencer to make it interchangeable for MOT.

Pros: Price

Cons: No jig so would need the car for 2-3 days = logistical nightmare

 

Powerspeed:

£1150+VAT - New Powerspeed 4-2-1 with silencer and integral cat.

+£250 fitted

+£70 P&P (probably cheaper to collect!)

They are open to bulkbuys (min qty. of 5) with 10-15% discount.

Pros: Use of jig to enable postage of complete system, or fitment by them in half a day.

Cons: Price!!!

 

Thoughts/advice welcome!

[Superwhite R283]

YHM

[Guest]

Quoting daz00004: 

YHM

[Guest]

I have agreed to buy a like-for-like exhaust replacement here (Cheers daz00004 )

 

It looks in much better condition than my existing exhaust, i.e. not rusty and with a nice shiny black heat shield, and the best bit is he lives a 2 min drive round the corner - what are the odds! This will not only tidy up the appearance of the car but also (hopefully!!) get rid of the annoying rattle. If I do decide to upgrade I can always sell this on.

 

I have ordered a new gasket to fit with the new exhaust - should I look to get new fixing nuts too?

 

Also, should there be any issues taking it from an early metric chassis to fit on my imperial chassis?

[Boris]

Hi Smiffy7,

 

If the exhaust your buying has any issues I have a k series Road Sport (SS) manifold and exhaust I looking to sell.

 

Came off my car at 4000 miles

 

Edited by - Boris on 7 Apr 2014 18:18:16

[Guest]

Boris,

 

Am I right in thinking your exhaust will be exactly the same as the one I linked to in my previous post? i.e. short 4-1 manifold within engine bay?

[Boris]

Sounds right

[Guest]

Thanks for the offer, Boris. I've picked up the new exhaust now and it looks to be pretty sound.

 

My car does not have the front of the two exhaust mounts/bobbins, so the whole system is held on by the one rear exhaust mount and the manifold bolted to the head. Is this considered OK for the standard exhaust or is it advised to get both mounts secured?

[shn7]

My last Seven only had the rear mount when I got it. I added the forward mount after I found that the exhaust cracked in front of the catalyst/can.

 

Whether that was just bad luck, limited track use or likely to happen in all cases given enough miles/time I couldn't say but I would advise adding the forward mount.

 

The only issue with that is locating the threaded boss in the chassis. I got someone to take some measurements from a car with the forward mount then drilled a small pilot hole to make sure I'd found the right place before opening it up further.

[Guest]

Steve, thanks for the advice. Having done a little searching of the archives it seems opinions are 50/50 on the merit of having the front exhaust mount. Those for having it argue it will prevent a cracking exhaust, as you do, while others suggest it puts extra strain on the rubber bobbins when the exhaust expands with heat. Given that I'd rather be replacing £1 bobbins than cracked exhausts I've got a mounting bracket on order to fit with the new exhaust. If I screw up my side panel I be coming after you, Steve!! 😬

 

Has anyone tried upgrading the exhaust with custom 4-1/4-2-1 external primaries but kept the standard silencer/cat, chop the old front section away with a bespoke collector joining the old can with the new primaries? Can't imagine the standard silencer posing much restriction on the engine, although happy to stand corrected...

Just thinking of saving some pennies

[shn7]

Hey don't blame me if it goes wrong blame the person you get the measurements fromshoulders mode> 😬 😬

[Guest]

Currently advertised in the For Sale section here

 

I am in the process of getting some more specific info from the seller regarding the car it came off, but his initial thought are it would fit, obviously with the side exit hole to be enlarged.

 

Assuming it will fit, what might I expect to see/feel in the way it drives, both low range and high revs? Conversely, would I be loosing out much compared to fitting say a 4-2-1 system from Powerspeed? Or is it a case of once you extend the manifold/primaries, any exhaust is just 6 of 1 half dozen of the other, with only the silencers offering differing sound/noise levels?

 

Cheers