R500 K pops bangs and pinking

[mark_w]

my engine is popping and banging when i lift off the throttle or drive at consistent revs also pinking (have i used the right term there) small knocks on tick over , looking for help in a things to check and work through , have had the exhaust and manifolds off recently which i thought may be a cause ...

 

thanks Mark

[Mark Durrant]

Mark

I woiuld start by checking that the T/B's are balanced and that there are no air leaks on both induction and exhaust. If the engine still has the standard map then I recommend you take the car to Track n Road in Rainham and get Steve Greenald to remap the engine. I had exactly the same issues with my R500K and the remap transformed the driveabiliity.   

[Adrian Williams]

Is this a new problem Mark or has it always done this?

Like Mark D mine always popped and banged on the overrun when I was using the standard map but stopped once it was remapped by Steve.

True pinking is pre ignition and not good news at all although I've never heard of an R5 being affected by it.  Pinking tends to show itself under load with a relatively large throttle opening combined with lowish revs so if yours is only making this noise at tickover it probably isn't pinking.

I'd follow Mark D's advice, balance TB's and check for air leaks as you've had the exhaust and induction off recently.

[mark_w]

It did run better when i first got the car a few months back but not perfect always popped bangs especially on start up. having had an alternator problem to sort havent had the opportunity to use much , i know the previous owner had it mapped at TnR after it was rebuilt at DVA.  So to balance the TBs is this done manually/visually or with specialist equipment and could any knocks on tickover be caused by air leaks from the exhaust or induction sides. the engine seems best under accelaration so good news its not pinking.  if its beyond me any recomendations as to who to take it to to get it checked out.

thanks Mark

[Richard K]

Mark,

If you can get over the 'The Hare' next Tuesday evening I sure there will be someone who can offer an opinion / advice.

I have an air flow tool that you could borrow.

http://www.retrodubs.co.uk/epages/Store3_Shop2367.sf/en_GB/?ObjectPath=/Shops/Store3.Shop2367/Products/AC000124

Richard

[mark_w]

thanks for the offer Richard will try to make it over , in the mean time will check for anything obvious

[Richard K]

Hi Mark,

I will be around on Saturday PM. I will give you a call to make contact.

My mobile no. does not work at home. No signal !

Richard

[Titanium7]

Mine was exactly the same on the original map but after the two Steves did their thing it stopped the popping and banging.

[mark_w]

thats great Richard Saturday pm will be good for me

im quite sure it has been mapped by the 2 steve's although checking through the history file i have with the car i can't find anything so i think i will call in on them to check as they are only a few miles from me 

Mark

[Richard K]

Mark - Blatmail sent with my address.

Ring my mobile if you need directions

Richard

[anthonym]

it sounds like this car might be relatively new to you? they do pop and bang on lift off.. mostly, and when cold they sound like a tractor... rattle rattle..

granted DVA and T&R treatments can be like magic, but any changes to the setup and the mapping becomes "Wrong". 

so letting in air would mix things up a bit.

lorra lorra fun though :-)

I've had mine .. a long time; what miles has yours done and what "refreshes"? 

edit: your comment about being best under acceleration may be a clue, since that's pretty much all they were designed to do, and then the opposite thing - not for cruising.

anthony

[mark_w]

thanks Anthony, probably a good summing up of how my car is will look at balacing the tbs this week and if i have no success then will have a visit to T&R got just over 9000 miles and had a refresh and a rebuild (scholar 1900 ) , it does drive so well with an open road in front so i think it is just a little off at tick over and lower revs . had a real good go at sealing the exhaust and has improved a lot since doing this, still loving owning and driving the car after 8 years since my previous caterham

[anthonym]

did DVA do the little mod he does to the the accelerator pot thing?  My tbs have I think nearly always been out and then I (meaning DVA)  found the accelerator pot was too... hang on a minute... was the T&R mapping BEFORE the scholar 1900 refresh? If it was, that mapping is now (way) outdated. 

I was forcibly informed that before going to T&R I MUST have the cam timing properly set up and, basically, regardless of who has previously set it up, it's considered now wrong and must be done now. I accepted that it made sense to KNOW that the cam timing was right for the dyno session (when my clutch promptly failed, but that's another story of user error).

p.s. and just to complicate matters there are two schools of thought about this cam setup process, neither of which I understand and both of whose proponents speak very darkly about the other view. One is something about doing it at TDC (top dead centre), I forget the other... maybe someone will be along momentarily to explain.

 

 

 

[mark_w]

don't know about the DVA mod being done , what exactly is that ? but the mapping was done after the DVA/scholar refresh i was told . and the cam timing by DVA looks like he uses the tdc method from his website. but yes the cam timing would need to be checked again before a dyno session as a waste of money otherwise... thanks Mark

[anthonym]

he modded the accelerator pot. yes he uses tdc. 

why not go see him with the car? 

[Mankee]

This may or may not be the correct way of doing it, but I've always set the cam timing up using the lift at TDC method as a base setting and then swung them around on a rolling road to see how power and torque are affected, power running after each change. Same with trumpet length. Repeat until the numbers no longer improve and revert to the previous best setting.

[mark_w]

Finally got around to having a go at the throttle bodies balance on Friday . using the syncrometer (thanks for the loan Richard) found the balance was a bit out so matching the 2 together and just increasing the tick over to 1000rpm has made a really big difference in how the car drives at lower revs  and they really were only minor adjustments,  very satisfying when you can get your hands dirty and make a difference yourself  . Didn’t find too much on the throttle pot mod on the DVA website apart from he packs it away from TBs with washers to stop it binding.  I have the car booked in at boss racing next week for them to have a look and check make comments and improve before I venture out with a few track days then we can start work on driver improvements   

[Adrian Williams]

[oilyhands]

Just for clarity, the 'throttle pot mod' is simply a matter of aligning the throttle pot so that it is returning the correct value when the engine is at idle, this ensures that the map in the ECU is correctly aligned with the throttle position as God intended. Occasionally the throttle pot will not turn enough to allow correct adjustment, in these situations it is necessary to elongate the holes in the TPS to allow correct adjustment, hence the 'mod'.

The two methods employed for timing cams are the lift at TDC method described on my website and the lobe centre or maximum lift point method. In my experiences the lift at TDC method is much easier to undertake and gives more accurate and repeatable settings.

Oily

[mark_w]

 

Hi Oily thanks for letting us know on the mod & cam timings, will get the idle voltage checked out at Boss next week 

Mark