Timing Marks

Author
Discussion

deetes

Original Poster:

413 posts

234 months

Sunday 6th July 2008
quotequote all
Does any one know of a manufactured adhesive tape that can be attached to a crank shaft pulley to give aditional timing marks, eg up to 40 degrees, in 2 degree increments?

Just for info, it's for a sick TVR390 running(not very well)Megasquirt.

The reason for the above is to verify the actual timing against that shown by MSqrt. I've been told that using the adjustment on my timing light will not give the correct reading due to wasted spark ignition.

Boosted LS1

21,188 posts

261 months

Sunday 6th July 2008
quotequote all
I'm not sure but iirc Real Steel may sell some tape like this. They're at Uxbridge.

deetes

Original Poster:

413 posts

234 months

Sunday 6th July 2008
quotequote all
Cheers

I'll give them a try tomorrow.

stevieturbo

17,271 posts

248 months

Sunday 6th July 2008
quotequote all
deetes said:
Does any one know of a manufactured adhesive tape that can be attached to a crank shaft pulley to give aditional timing marks, eg up to 40 degrees, in 2 degree increments?

Just for info, it's for a sick TVR390 running(not very well)Megasquirt.

The reason for the above is to verify the actual timing against that shown by MSqrt. I've been told that using the adjustment on my timing light will not give the correct reading due to wasted spark ignition.
Wasted spark will read double on the light. It isnt complicated, and you dont need extra markers unless its a cheap crap TDC only timing light.

deetes

Original Poster:

413 posts

234 months

Monday 7th July 2008
quotequote all
[quote=stevieturbo

Wasted spark will read double on the light. It isnt complicated, and you dont need extra markers unless its a cheap crap TDC only timing light.
[/quote]

The timing light I have has adjustment to allow you to check the timing using the TDC mark, which is usually larger, then read the timing from the scale on the adjustment. Would this be OK?

This could mean that my trigger angle is way out, although I checked it against the marks that are on the pulley.

The reason for asking this is that the engines not running worth a damn, gutless yet still pinking. Lost 50bhp on the dyno since last year. When I checked the timing against what the MS was reading the actual reading was greater and as the rpm increased this difference got bigger, but at no time was it double the MS reading.

rev-erend

21,421 posts

285 months

Monday 7th July 2008
quotequote all
Reelsteel do sell the tape but you can and should establish an accurate TDC and mark and needed reference timing on the pulley with some tipex and an engine portactor (degree wheel).

Have a look here for some info on this :

http://www.g33.co.uk/tuning.htm

Edited by rev-erend on Monday 7th July 09:04

eliot

11,444 posts

255 months

Monday 7th July 2008
quotequote all
I bought the real steel one, unfortunatley it fell off a couple of days later.
So I made my own one using visio.
http://www.mez.co.uk/ms9.html

deetes

Original Poster:

413 posts

234 months

Monday 7th July 2008
quotequote all
Timing lights packed in anyway, so I'll have to find out what's wrong with it or invest in a new one.

Pulled all the plugs and had a look at them. All black as a really black thing on a dark night, but it hasn't had a decent run for a while, so it's just been ticking over etc in the garage while I try to figure out what's causing it to misfire. Reset the gaps from 1mm to 0.9mm. No difference.

stevieturbo

17,271 posts

248 months

Monday 7th July 2008
quotequote all
Buy, or get a lend of a proper adjustable timing light.

Wasted spark....ign timing is 10deg, light will flash 20
timing is 20deg, light will flash 40deg and so on.

deetes

Original Poster:

413 posts

234 months

Monday 7th July 2008
quotequote all
Cheers

eliot

11,444 posts

255 months

Monday 7th July 2008
quotequote all
stevieturbo said:
Buy, or get a lend of a proper adjustable timing light.

Wasted spark....ign timing is 10deg, light will flash 20
timing is 20deg, light will flash 40deg and so on.
Hi steve,
do you mean it will flash at 10 & 20 ?
With my old timing light it appears to jump around possibly between say 10 and 20. But using my mates snap-on light it appears steady at the desired adv.


stevieturbo

17,271 posts

248 months

Monday 7th July 2008
quotequote all
AT 10 degBTDC actual timing as indicated on your ecu. The timing as flashed on the timing light will be 20deg BTDC.

AT 20 degBTDC as actual timing indicated on your ecu. The timing as flashed on the timing light will be 40deg BTDC.

Wasted spark flashes double, same way the rpm signal on the timing light will also read double what the actual rpm of the engine is.

Get a Snap On light...no messing about smile

Steve_D

13,749 posts

259 months

Monday 7th July 2008
quotequote all
I made a mistake with my timing light in not realising the pickup that clips around the outside of number one lead has an arrow on it that must point towards the spark plug. With it fitted the wrong way round I had lots of scatter and missed sparks.

Steve

eliot

11,444 posts

255 months

Monday 7th July 2008
quotequote all
stevieturbo said:
AT 10 degBTDC actual timing as indicated on your ecu. The timing as flashed on the timing light will be 20deg BTDC.

AT 20 degBTDC as actual timing indicated on your ecu. The timing as flashed on the timing light will be 40deg BTDC.

Wasted spark flashes double, same way the rpm signal on the timing light will also read double what the actual rpm of the engine is.

Get a Snap On light...no messing about smile
Not entirley sure about that steve, because i set mine up around 10' (limp mode) with my old light and was getting similar (but more steady) results with my mates snap-on light. I will borrow it again to double check though.

stevieturbo

17,271 posts

248 months

Tuesday 8th July 2008
quotequote all
I am sure smile

bertelli_1

2,240 posts

211 months

Tuesday 8th July 2008
quotequote all
eliot said:
Not entirley sure about that steve, because i set mine up around 10' (limp mode) with my old light and was getting similar (but more steady) results with my mates snap-on light. I will borrow it again to double check though.
He's right. Don't you remember messing about with my car on your driveway & trying to figure out why it idled so well with 20deg of advance but ran rough with 10deg?

eliot

11,444 posts

255 months

Tuesday 8th July 2008
quotequote all
bertelli_1 said:
He's right. Don't you remember messing about with my car on your driveway & trying to figure out why it idled so well with 20deg of advance but ran rough with 10deg?
I need to borrow your light and double check things chap.

deetes

Original Poster:

413 posts

234 months

Thursday 10th July 2008
quotequote all
stevieturbo said:
AT 10 degBTDC actual timing as indicated on your ecu. The timing as flashed on the timing light will be 20deg BTDC.

AT 20 degBTDC as actual timing indicated on your ecu. The timing as flashed on the timing light will be 40deg BTDC.

Wasted spark flashes double, same way the rpm signal on the timing light will also read double what the actual rpm of the engine is.

Get a Snap On light...no messing about smile
The above would mean my trigger angle could be wrong????

stevieturbo

17,271 posts

248 months

Thursday 10th July 2008
quotequote all
I dont know what your trigger angle is.


But if when performing the tests I mentioned, results arent as I said, then something is wrong.

eliot

11,444 posts

255 months

Thursday 10th July 2008
quotequote all
I think this is possibly where the confusion is stemming from. Even when using the snap-on light, I still had the dialback set to 0 - so its essentially the same as my cheapo light. I relied on my timing tape to get the actual advance figure.

I think the doubling of the advance value is only present when using the dial-back feature - right steve?