RAF Portreath 1/4 mile sprint

[zz top]

Last weekend quite a few of the Devon and Cornwall TVR car club entered a well organised 1/4 mile sprint at the disused RAF airfield in Cornwall.Apart from the 100 odd motorbikes that took part,other marques were there including Porkers,Lotus,Westfields,Astons,Red Donkey's.and some heavy yanky machines. Im glad to say that Blackpools finest set the pace.However,on my last run i noticed a rapid,loud "knocking" engine noise on decelleration.I immediately cut the engine,then threw my helmet off in despair and thought about the recent cost of all my engine mods. After 10 mins i re-started the engine and she was and is still.........purrfect! The only thing i noticed was that the Mobil 1 oil was like water. Could this be the oil pump not being able to cope under extreem pressure?.Your thoughts please...zz

[Guillotine]

hey ZZ...long time no see.

huummmm, running ok now, (not sure which mods are on board-other than the "carlos fandango super wide wheels "

posibly some detonation probs. max throttle for extended periods, too much fuel (yes there can be such a thing) rapid decelleration, possibly stuck advance.


could be running lean, this is MUCH more serious and could do MAJOR damage. unlikely i would suggest as you would here big clattering ON load not OFF load.

wouldn't worry about it TOOOO much if its not doing it in normal use. give it a little bit extra on the next run-EXTREME CAUTION, to see or if nervous (like me) get Big Col to do the norm, ie compression & bleed down checks to make sure the nuts and bolts are ok.


BYW you mentioned a sprint meet last time we met...wasn't it was it? havn't missed it have I?

>> Edited by Guillotine on Wednesday 23 June 21:58

[HarryW]

Definately engine , Only ask that as I've had some very weird noise from the diff on deceleration from high speed when very hot before now on rough runways. Not alone in that others have experienced it too at Duxford and Bruntingthorpe before.
Just a thought, looking on the bright side.
Any timing equipment there , if so what sort of times/speed were being achieved.

harry

[zz top]

Hi guy's, Yep Andy this was the sprint i mentioned, however the Cornwall Sports Car and Bike Club do intend to run the event again in September, at the same venue. My best run for the 1/4 mile was 14.1 secs with a speed of 125 mph but with a poor reaction time of .7sec away from the lights. I think Tony Hockings 4.5 Cerb achieved the best time of 13.8 secs with a speed of 127mph with a quick reaction time of .3sec. My problem was far too much wheel spin off the line and changing into 2nd, 3rd and 4th gears. That was awesome, even the bikers were impressed with that! Still can't fathom out what this noise is or where it came from. Did scare the shit out of me though. zz

[HarryW]

Do thjose times include the reaction times, because if you take the drivers reactions out, the griff managed 13.4sec and the cerb 13.5secs .
Still very respectable times, I would have thought that at 127mph you were running out of revs in 4th too .

Harry

>> Edited by HarryW on Wednesday 23 June 23:42

[DustyC]

HarryW said:

Still very respectable times, I would have thought that at 127mph you were running out of revs in 4th too . Harry >> Edited by HarryW on Wednesday 23 June 23:42

At least another 13mph to go in forth.
Only tried it once by accidnet. Didnt hit the limiter either.

Those times sound pretty good.
My handbook states 12.2 secs. I thought it sounded unrealistic!

[DustyC]

ZZtop, there is a big drag event at Thorney Island (Hampshire) on 18th July that a few of us are attending.

I'll quote your times in the relevant thread as none of us have a clue what we are gonna get.

[zz top]

HarryW said:

Do thjose times include the reaction times, because if you take the drivers reactions out, the griff managed 13.4sec and the cerb 13.5secs . Still very respectable times, I would have thought that at 127mph you were running out of revs in 4th too . Harry >> Edited by HarryW on Wednesday 23 June 23:42

Yep those times did include the reaction times. Someone suggested putting a bag of cement in the boot to keep the back end down. Drastic measures...zz

[zz top]

DustyC said:

ZZtop, there is a big drag event at Thorney Island (Hampshire) on 18th July that a few of us are attending. I'll quote your times in the relevant thread as none of us have a clue what we are gonna get.

Fantastic, i'll see if i can reorganise my diary and come along maybe with a few others from Devon. Let you know..zz

[Guillotine]

need to post in advance ZZ, would have liked to have come along.

can't make the hampshire one, will be on the track...


AT LE MANS!

[zz top]

Guillotine said:

hey ZZ...long time no see. huummmm, running ok now, (not sure which mods are on board-other than the "carlos fandango super wide wheels " posibly some detonation probs. max throttle for extended periods, too much fuel (yes there can be such a thing) rapid decelleration, possibly stuck advance. could be running lean, this is MUCH more serious and could do MAJOR damage. unlikely i would suggest as you would here big clattering ON load not OFF load. wouldn't worry about it TOOOO much if its not doing it in normal use. give it a little bit extra on the next run-EXTREME CAUTION, to see or if nervous (like me) get Big Col to do the norm, ie compression & bleed down checks to make sure the nuts and bolts are ok. BYW you mentioned a sprint meet last time we met...wasn't it was it? havn't missed it have I? >> Edited by Guillotine on Wednesday 23 June 21:58

Andy noticed you have fitted an oil cooler to your beast, something that my pre-serp 500 hasn't got. Recommend it?...zz

[Guillotine]

yes, but will have to let you know when finished!

need one for the track work...oil gets too thin! even Mobil Msport.

helps keep temps down too, BUT...

have put it in the air filter slot, so have to resite filter, which i havn't done yet. currently have air filter in engine compartment so losing 20-30 bhp almost back to standard . but it won't be staying there. have tried a couple of slots already but not really suitable so will have to see. must get sorted for LeMans.

[zz top]

Guillotine said:

yes, but will have to let you know when finished! need one for the track work...oil gets too thin! even Mobil Msport. helps keep temps down too, BUT... have put it in the air filter slot, so have to resite filter, which i havn't done yet. currently have air filter in engine compartment so losing 20-30 bhp almost back to standard . but it won't be staying there. have tried a couple of slots already but not really suitable so will have to see. must get sorted for LeMans.

Andy,LE MANS....lucky bast*rd, just you make sure you keep that beast on the tarmac. Let me know how the oil cooler comes along..zz

[Guillotine]

Le Mans...then onto Dijon!