New member, old cerb
Discussion
scerbera said:
Seems lumpy curves,
mine look like
Hi Byker,
My chap wasn't keen on touching the mbe ecu, are there people who will? quite bizarre curve isn't it.
I think the cam timing is probably off also, there is 60k on the clock and chain has probably stretched a fair bit. Also using a fair whack of oil so guides, seals and rings are probably not brilliant.
Your torque comes in much later than mine, i'm between 300 and 320 between 2500 to 5500 then dropping quick. Yours is hitting 300 at 3500 but staying above 300 till 6700ish then only dropping to 275 at redline.
very rich smell of fuel in the dyno cell also.
I'm west wales based but travel to cardiff and m4 sometimes, who's my best contact for further investigation?
My chap wasn't keen on touching the mbe ecu, are there people who will? quite bizarre curve isn't it.
I think the cam timing is probably off also, there is 60k on the clock and chain has probably stretched a fair bit. Also using a fair whack of oil so guides, seals and rings are probably not brilliant.
Your torque comes in much later than mine, i'm between 300 and 320 between 2500 to 5500 then dropping quick. Yours is hitting 300 at 3500 but staying above 300 till 6700ish then only dropping to 275 at redline.
very rich smell of fuel in the dyno cell also.
I'm west wales based but travel to cardiff and m4 sometimes, who's my best contact for further investigation?
scerbera said:
My chap wasn't keen on touching the mbe ecu, are there people who will?
Yes! Joolz and Dom!http://www.powersperformance.co.uk/
I would down load the software and plug a laptop into the ecu.
those traces looks all over the place and a noisy throttle pot or something similar could cause that, so could a failing coil pack, the software will help you diagnose the issues.
It does sound like it could do with a top end refresh, ask your mech to see what the valve clearances are like and how thick the shims are, the valves stretch which causes problems as well.
Jules and Powers performance both good at mapping the MBE but I doubt it needs it, this looks more like something has worn rather than a duff map.
Maps don't wear out.
those traces looks all over the place and a noisy throttle pot or something similar could cause that, so could a failing coil pack, the software will help you diagnose the issues.
It does sound like it could do with a top end refresh, ask your mech to see what the valve clearances are like and how thick the shims are, the valves stretch which causes problems as well.
Jules and Powers performance both good at mapping the MBE but I doubt it needs it, this looks more like something has worn rather than a duff map.
Maps don't wear out.
scerbera said:
Hi Byker,
My chap wasn't keen on touching the mbe ecu, are there people who will? quite bizarre curve isn't it.
I think the cam timing is probably off also, there is 60k on the clock and chain has probably stretched a fair bit. Also using a fair whack of oil so guides, seals and rings are probably not brilliant.
Your torque comes in much later than mine, i'm between 300 and 320 between 2500 to 5500 then dropping quick. Yours is hitting 300 at 3500 but staying above 300 till 6700ish then only dropping to 275 at redline.
very rich smell of fuel in the dyno cell also.
I'm west wales based but travel to cardiff and m4 sometimes, who's my best contact for further investigation?
There's 52K genuine miles on mineMy chap wasn't keen on touching the mbe ecu, are there people who will? quite bizarre curve isn't it.
I think the cam timing is probably off also, there is 60k on the clock and chain has probably stretched a fair bit. Also using a fair whack of oil so guides, seals and rings are probably not brilliant.
Your torque comes in much later than mine, i'm between 300 and 320 between 2500 to 5500 then dropping quick. Yours is hitting 300 at 3500 but staying above 300 till 6700ish then only dropping to 275 at redline.
very rich smell of fuel in the dyno cell also.
I'm west wales based but travel to cardiff and m4 sometimes, who's my best contact for further investigation?
What you don't see is all my torque bangs in at 2K revs, it's what I had it mapped for to make it more driveable. This is the graph with a coil pack breaking down and cracked exhaust manifolds.
and this is an early graph just after I got the car. Noisy throttle pots, a lambda sensor and a decent full service sorted this out
The camel hump at the top is normal for Factory cars. If the car has been mapped correctly then that's smoothed out.
gruffalo said:
those traces looks all over the place and a noisy throttle pot or something similar could cause that, so could a failing coil pack, the software will help you diagnose the issues.
The coil packs are new - not cheap Chinese either - (had only done around 600 mile) and the throttle pots are brand new items from Clevor Trevor (about a month old). The lambdas are new NGK, the plug leads are 8mm and new. The plugs are NGK and as new.As for the comment, 'neglected', I spent £4,000 in 12 months and the previous owner just under £7,000 and he covered around 1,500 miles I think. All the work for him was done by a TVR dealer up Selby way (according to the invoices).
The car was virtually unused for 4 years. So all the hassle that Scerbera has had - the heatshield held on with self tappers, the screws not coming out of the housing and suchlike - just shows how good some of these specialists really are.
The brakes may well have a tired servo but I never tracked the car and having nothing to compare it with they seemed fine to me. Always managed to stop okay but then I didn't drive like Lewis. On the MOT - 6 weeks or so ago - the tester said they were balanced and pulled a good reading on his brake tester, except the handbrake of course. This was not a 'TVR Friendly MOT Station' either so to achieve CO of 0.08, HC somewhere around 20ppm (can't remember the exact figure) and Lambda of 1.02 for a neglected engine is nonsense.
Agree with Jamie. Needs to go to the top people for the correct advice.
Edited by N7GTX on Friday 10th October 17:20
N7GTX said:
gruffalo said:
those traces looks all over the place and a noisy throttle pot or something similar could cause that, so could a failing coil pack, the software will help you diagnose the issues.
The coil packs are new - not cheap Chinese either - (had only done around 600 mile) and the throttle pots are brand new items from Clevor Trevor (about a month old). The lambdas are new NGK, the plug leads are 8mm and new. The plugs are NGK and as new.As for the comment, 'neglected', I spent £4,000 in 12 months and the previous owner just under £7,000 and he covered around 1,500 miles I think. All the work for him was done by a TVR dealer up Selby way (according to the invoices).
The car was virtually unused for 4 years. So all the hassle that Scerbera has had - the heatshield held on with self tappers, the screws not coming out of the housing and suchlike - just shows how good some of these specialists really are.
The brakes may well have a tired servo but I never tracked the car and having nothing to compare it with they seemed fine to me. Always managed to stop okay but then I didn't drive like Lewis. On the MOT - 6 weeks or so ago - the tester said they were balanced and pulled a good reading on his brake tester, except the handbrake of course. This was not a 'TVR Friendly MOT Station' either so to achieve CO of 0.08, HC somewhere around 20ppm (can't remember the exact figure) and Lambda of 1.02 for a neglected engine is nonsense.
Agree with Jamie. Needs to go to the top people for the correct advice.
Edited by N7GTX on Friday 10th October 17:20
The dyno trace is similar to bykers first when bought but not the same issue I think.
I am going to put her away for winter soon so will check all the grounds, valve clearances, possibly have the head off and check the valves e.t.c
Unless anyone else has any suggestions to look at?
gruffalo said:
8mm plug leads you say, I think we may have just found the issue.
Cerbs don't like 8mm leads, there have been many threads about miss fires after people have fitted new plugs and leads, often magnecor leads, for some reason they cause a problem not on every car but on many.
Very interesting and thanks for the response. They are cheap enough to try!Cerbs don't like 8mm leads, there have been many threads about miss fires after people have fitted new plugs and leads, often magnecor leads, for some reason they cause a problem not on every car but on many.
Thanks Gruffalo, I have ordered a set so will see if I can notice a difference. Will try a new lead prior and if app works can compare before and after.
It does rather smell of fuel especially on the dyno.
Another question, how much oil should they use?
It seems to be going through it, the oil pressure gauge drops to zero after around 300 miles when your going down a hill, I have then topped up and it's then fine. No obvious oil leak, I'm not familiar with the oil pickup on this engine, is it a problem commonly reported?
There is a little smoke when pushed hard above 5k and a fair bit on the over run between 5 and 6k but nothing too bad. Could be worn guides or stem seals.
I'm also wondering if it's getting pulled through the breather which I haven't investigated.
I'm not talking litres but probably 300 ml I've put in 2 or three times in 1000 miles.
It does rather smell of fuel especially on the dyno.
Another question, how much oil should they use?
It seems to be going through it, the oil pressure gauge drops to zero after around 300 miles when your going down a hill, I have then topped up and it's then fine. No obvious oil leak, I'm not familiar with the oil pickup on this engine, is it a problem commonly reported?
There is a little smoke when pushed hard above 5k and a fair bit on the over run between 5 and 6k but nothing too bad. Could be worn guides or stem seals.
I'm also wondering if it's getting pulled through the breather which I haven't investigated.
I'm not talking litres but probably 300 ml I've put in 2 or three times in 1000 miles.
1litre per 1000 miles I would say is not excessive but she should not be smoking.
Regarding your oil pressure, they do drop on braking when you don't have sufficient oil in them and the dip stick is really hard to read properly. The only way I have found is to park on flat ground and remove the dipstick, come back in the morning and dip once, every time you pull the dipstick it pulls oil up the tube giving a falsely high reading. I typically over fill mine slightly to prevent this oil starvation on braking.
The engine is normally bullet proof but the valves stretch and sometimes the guides wear. Engine out job to sort them and only one place I would trust and they are in Oxfordshire.
Regarding your oil pressure, they do drop on braking when you don't have sufficient oil in them and the dip stick is really hard to read properly. The only way I have found is to park on flat ground and remove the dipstick, come back in the morning and dip once, every time you pull the dipstick it pulls oil up the tube giving a falsely high reading. I typically over fill mine slightly to prevent this oil starvation on braking.
The engine is normally bullet proof but the valves stretch and sometimes the guides wear. Engine out job to sort them and only one place I would trust and they are in Oxfordshire.
scerbera said:
gruffalo said:
8mm plug leads you say, I think we may have just found the issue.
Cerbs don't like 8mm leads, there have been many threads about miss fires after people have fitted new plugs and leads, often magnecor leads, for some reason they cause a problem not on every car but on many.
Very interesting and thanks for the response. They are cheap enough to try!Cerbs don't like 8mm leads, there have been many threads about miss fires after people have fitted new plugs and leads, often magnecor leads, for some reason they cause a problem not on every car but on many.
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