1.8 K series go faster bits - WHY

[Highside43]

I have the 1.8 SS K series (non VVC - 1998 model) which according to Caterham is meant to be 140bhp.

Having had it dyno'd yesterday and it was giving out a paltry 77bhp, I'm after the following please:-

 

Free'er flowing exhaust

Throttle bodies

Piper Cams Verniers

Programmable ECU

 

Just want to make it breath more in and out to start with and give it a few more BHP over standard.

Many thanks.

[TomB]

Id be looking at what's wrong with it before fitting go faster bits.  It doesn't sound right at all. Even in standard Rover, non Superport, it produced 120bhp.  

[Highside43]

Tom,

From my limited knowledge - and I'm only an enthusiastic DIY mechanic - it can only be one of two things:-

1) - not getting enough mixture.

2) - not getting exhaust out.

The car runs fine, pulls reasonably well low down, but when you get to 4.5 / 5K it just runs out of puff - it will rev to 6.5K but as I've said in previous posts, it feels asthmatic doing so.  It ticks over fine, it doesn't cough or hesitate when you drive it, it doesn't smoke, spark plugs correct colour...etc...all the usual checks tick.  There is nothing untoward with the running of the engine until you drive it and feel how gutless it is, it sounds fine and not like a box of frogs at all.  Changed oil and nothing untoward in that.  Same for coolant. So I'm scratching my head.  If it sounded terrible on start-up, or made a load of clanging noises when driving then at least you could say the engine was shot, but it doesn't give any clues to how feeble it is unless you boot it.  During normal road driving you wouldn't tell anything was wrong with it.

I want to tune it slightly anyway, and future proof it for more tuning - so if it is a completely knackered CAT in the exhaust (I don't think it is, but it will eliminate that possibility of a blocked by putting a free'er flowing exhaust on ready for the future tune).

Likewise with the throttle bodies and ECU - once set up it should pull like an express train.

Again, I'm no expert but I think the cam timing is way, way out (from possibly a belt change previous???) - I'm not competent enough to adjust this, but my diagnosis with how the engine physically runs and feels, it can't be opening the valves soon enough and closing them too quickly.

Unless I'm on the wrong path altogether?

[The_ASH]

You could actually have a bit more power than that, drivetrain power loss could reduce the headline figure by 15 or so percent (the Caterham 140 figure would have been at the flywheel) even then though it might mean you only have 90hp. It might be worth physically proving you actually have Supersport cams installed. After that fitting vernier pulleys and making sure everything is timed correctly might improve things greatly. Another thing I've heard suggested that can sap K power is incorrect oil level if overfilled it doesn't clear the foam quick enough and thrashes around in the crank case absorbing power and creating heat, not sure how true this is though, there are guides on here pointing how to get an accurate level reading.

[Highside43]

Caterham confirmed the engine and tune / power.  The car has had one owner from new until I purchased it last year, so unlikely that the cams would have been swapped in it's 36,000 mile history - but a possibility I have considered though.

I suspect timing is way out too, but i have very limited mechanical knowledge and relying on Google a lot.

[TomB]

Have a look at Dave Andrews k series pages.  You find a section on cam timing with vernier pulleys and the cheaper off-set dowel option.  

Have you a a Haynes manual for the engine?  To work out whether the standard pulleys are properly fitted you set the engine to Top Dead Centre and the mark on the standard pulley should line up.  If they don't that suggests the cam timing would be out for standard pulleys, let alone the SS cams.  

Fitting the vernier pulleys isn't too hard - with a manual and some support in the garage, its well within the competence of a DIY mechanic.  Its the same process as removing/ refitting the standard ones.  Timing of them requires a pair of dial gauges and some welding rods.  Not too hard conceptually, but its helps to watch or have someone who has done it before.

When the verniers are on, you slacken off the bolts securing the centre of the pulley, and twist the camshaft, observing the lift on the dial compared to what it should be.    

Its also a good opportunity to replace the timing belt if its not been done. 

 

[Jonathan Kay]

See also this thread.

Jonathan

[Ed White]

When it was on the dyno, why didn't the operator get involved with adjusting fueling etc.? Was it just a straight dyno run, ie on/off here are results?

[grumpy the 7th]

Quoting The_ASH

"Another thing I've heard suggested that can sap K power is incorrect oil level if overfilled it doesn't clear the foam quick enough and thrashes around in the crank case absorbing power and creating heat"

Get rid of the foam!!!!!!!! - and do the 2 holes in the gasket mod. plenty of posts under "foam or baffle etc"