Timing Advise please

[Black_65]

Hi Guy's,

Sorry to bother all you but in need of some advice on 'timing'.

I have a 2165cc on 48 dells, FK10 on 10.1 c/r using a programmable ignition box with a 009 dizzy.

I've had the motor set up and dyno'd but every since i've fitted it to the car its not running right under load. It feels like its holding back/retarding around 4500rpm and really has to fight past 5.5-6k rpm.

My question is what's a good number to be setting my timing on a 009 dizzy with electric ignition kit (taken off the programmable box) to try and drive before i get some cash to have it set up on a rolling road.

I've set it at 32 deg around 3500rpm, But was thinking of trying 28-29 deg...

What's your views guy's

[glenn]

I initially set my 2180 (FK8 Bosch 010) to 32 degrees. After a few weeks I dropped it to 30 degrees with no loss of power and lowered oil temps a few degrees.

[Black_65]

Here's a picture of the ignition mag that was set when it made 161hp at GAC.



The dizzy is locked out, and set at 10 deg at idle around 1000rpm. That's why the plots are 10 deg less on the programmable box.

At the moment i've removed the 'lock out' dizzy and fitted a 009 dizzy.

[Black_65]

I initially set my 2180 (FK8 Bosch 010) to 32 degrees. After a few weeks I dropped it to 30 degrees with no loss of power and lowered oil temps a few degrees.

What rpm did you set it at 30 if you don't mind asking

[glenn]

Full advance.... The 010 is at full advance at 2800rpm.

[nicolas]

is this happening when you accelerate? and less if you go up the RPMs more gently? if so it is the spring in the distributor that can't follow the rpms and it floats. i had it on my 2276 with a 009, went to a module and it will rev way past 6500 now.

maybe this helps

[Taylor]

Ummmm....... I think with the accuspark box each degree is in distributor degrees which would be doubled at the crank. So maybe you have like 52 total advance. Check it with a real timing light.   Pretty sure I'm right. Let us know.  Taylor

[Torben Alstrup]

Hello.
I was thinking - not much power with that FK10, right up until I saw the pics of your engine. The Porsche fan is too high ratioéd. It will drag about 20 hp in that set up. You should ratio it down to the point where it drags 10-13 hp max. That will typically be about 1,2 - 1.
Also your intake length is almost certainly too long. About 1½ - 2" judging from pics.

Set timing to 30 btdc, reduce stack length to about ½ of what you have, and take it for a spin with out the fan belt and see how it responds. I´m pretty sure it will pick the rpms up somewhat better.

T

[Black_65]

Hello.
I was thinking - not much power with that FK10, right up until I saw the pics of your engine. The Porsche fan is too high ratioéd. It will drag about 20 hp in that set up. You should ratio it down to the point where it drags 10-13 hp max. That will typically be about 1,2 - 1.
Also your intake length is almost certainly too long. About 1½ - 2" judging from pics.

Set timing to 30 btdc, reduce stack length to about ½ of what you have, and take it for a spin with out the fan belt and see how it responds. I´m pretty sure it will pick the rpms up somewhat better.

T

Hi Buddy,

Thanks for the advice. The latest picture of the motor i've fitted a 5 1/4" pulley from CB and its made the world of difference..! It's cooling better and doesn't wine anymore up the rev's.

As for the stacks, I was told to buy these 100mm tall stacks as Alan at GAC said they fitted them to help dial out a bad spot on the power and it worked.

As for taking the belt off, It still doe's the issue i'm having as we was trying it on the track 

[Black_65]

Ummmm....... I think with the accuspark box each degree is in distributor degrees which would be doubled at the crank. So maybe you have like 52 total advance. Check it with a real timing light.   Pretty sure I'm right. Let us know.  Taylor

I will thanks , I was using a cheap timing gun but a mate of mine has a snap on one so that will do the trick.

So i get it right, If its correct like your saying with a good gun and its doubled, Will i need to HALF the timing deg's plots?

The whole thing is odd really as the issue im having with the power holding back doe's it with the locked out dizzy using the programmable box and doe's it with a 009 fitted with electric ignition kit. It even doe's it with the belt off....

Very lost with the whole thing. I doesn't do it at all when static and i rev it, only under load.

[Taylor]

http://m.youtube.com/watch?v=XPtmDx8lZ9U
Here the guy talks about the timing for the accuspark.

[Black_65]

Ummmm....... I think with the accuspark box each degree is in distributor degrees which would be doubled at the crank. So maybe you have like 52 total advance. Check it with a real timing light.   Pretty sure I'm right. Let us know.  Taylor

As Accuspark is one of my sponsors, I had him take a look at the 'timing map'. He said all looked good, but the way he designed the box is so that you set the dizzy at what ever you need i.e 10 deg. Then the box doe's the rest for the advancing if that makes any sence lol...

What i do remember is that the 'fixed advance box' in the top left hand corner of the system. That what's in 'crank deg' so if i wanted 12 deg. I would have the dizzy set at 10 deg and i'd set the 'fixed advance' to 1 (which would be 2 deg's).

Also looking at the ignition map and thinking about what rev's the 009 max advance is, Is it advancing too late on the programmable box as on the map it say's 4300rpm at 32 deg max advance.

[Black_65]

http://m.youtube.com/watch?v=XPtmDx8lZ9U
Here the guy talks about the timing for the accuspark.

Yep that's Tony at Accupark lol...

So you was right but so would i need to get 'fixed advance' at 10 deg's for idle and then plan the map different to what i have now?

[Taylor]

I think you have another problem going on.  Maybe start tracking it down by setting your distributor to 28 degrees advance and set your timing plot to 0 across the board. Then drive around and see if it's still there.

[Torben Alstrup]

The advance curve is also waaay too slow (long)
Dependant on where your throttle plates are at idle you should be at 8-11 degrees at idle. Progression should begin at 1000 - 1050 rpm. be 17-20 @ 2000 and all in between 2700 & 2800 rpm. (30-32 degrees BTDC)
When you do that you will most likely also cure, or at least minimize that flat spot in the fuel delivery, so you can reduce the intake length.
As to why it is reluctant reving, I do not know. - Are you sure your tach is right ?

A print of the dyno sheet + basic engine specifications might reveal something.

T

[Black_65]

The advance curve is also waaay too slow (long)
Dependant on where your throttle plates are at idle you should be at 8-11 degrees at idle. Progression should begin at 1000 - 1050 rpm. be 17-20 @ 2000 and all in between 2700 & 2800 rpm. (30-32 degrees BTDC)
When you do that you will most likely also cure, or at least minimize that flat spot in the fuel delivery, so you can reduce the intake length.
As to why it is reluctant reving, I do not know. - Are you sure your tach is right ?

A print of the dyno sheet + basic engine specifications might reveal something.

T

Should i try an re mag it using a base setting like the one above you have listed? Also sorry to be a pain but what's the difference in BTDC?

Here's the dyno print out, The AFR (black line) went abit odd as the motor before mine was on high end race fuel.



As for the tacho, I'm using a auto meter pro-comp tacho.

I'm really looking forward to plying around with it. Like i said i have a 009 in at the moment but won't take me long to change the dizzy and play around with the box and using a good timing gun

[Peter]

like already said,
just put 30 or 32 degrees for all rpms,
that's the easiest way to check if its the curve or not

[Torben Alstrup]

Before Top Dead Center. Just another way of writing.

But its definitely not jetted correct. I´d say the relation between the air jet, E tube and main jet is wrong. If we take the spike out it is still leaning too much out in the top end.

We need the full engine combo, exhaust, carbs and jets included to get the picture and see if we can spot the anomali.

The power curve itself actually looks quite OK, but dependant on combo it should pull higher. But if the combo is conservative it the peak power might be right.
You can also try and take a measure of your intake length. for such an engine you should be in the 14,5 max 15" from valve to top of stack. (The book says up to 16", but that is usually too long in real life.)

T

[Black_65]

Before Top Dead Center. Just another way of writing.

But its definitely not jetted correct. I´d say the relation between the air jet, E tube and main jet is wrong. If we take the spike out it is still leaning too much out in the top end.

We need the full engine combo, exhaust, carbs and jets included to get the picture and see if we can spot the anomali.

The power curve itself actually looks quite OK, but dependant on combo it should pull higher. But if the combo is conservative it the peak power might be right.
You can also try and take a measure of your intake length. for such an engine you should be in the 14,5 max 15" from valve to top of stack. (The book says up to 16", but that is usually too long in real life.)

T

I will list below the full engine spec, As for the jet's i have no idea as some of them was drilled out to jet the carb's right. This was all done before the motor was set up and put on a engine dyno. Just a quick one on the fueling, AFR gauge on the car looks good though out the rev range while driving.

2175cc spec : C/R 10:1.1 BHP (161.4hp) = Aug 2013

- Full Flowed Autolinea Case (all the good bits)
- 78.4 Stroker Crank (balanced)
- 94mm Mahle barrels and Pistons with Total seal Rings (balanced)
- H Beam Rods (5.5)
- CB 1.4 Ratio Rockers
- Engle FK10 Cam with straight Cut Cam gear
- 044 Heads with Dual Valve Springs 42 x 37 (wedge ported and polished)
- Shadek 26mm Oil Pump with CSP relif cover
- 48 DRLA Carbs, 100mm stacks with 'big beef' tall manifolds (matched ported)
- Empi Deep Sump
- Lightened 8 Dowelled Flywheel (balanced)
- Kennedy stage 1 pressure plate with Dalkin super disc
- 5 1/4" CB pulley with a 825mm belt
- 1 5/8 merged header & box (speed shop)
- Accuspark performance coil, 8mm leads, 009 dizzy with electric ignition, rev-limiter
- Porsche T1 fan set up with a 11 blade fan
- Remote oil cooler and filter



Here's a little video from the other day,



I think tomorrow i will try and set the timing at 30 deg and change the stacks to the 50mm tall ones and see how shes playing.

If not i really thank you for all the help and advice, I will have to wait to get it on a rolling road, jetted, timing again.

[Torben Alstrup]

Snappy little thang!

Nothing serius sticks out. Is it hand ported wedge ports or a set of CB´s that have been further massaged ?

I think the problem may be a mix between igntion, intake length, and the fan dragging hard at rpm. But not sure.

T

[Black_65]

Snappy little thang!

Nothing serius sticks out. Is it hand ported wedge ports or a set of CB´s that have been further massaged ?

I think the problem may be a mix between igntion, intake length, and the fan dragging hard at rpm. But not sure.

T

The heads are CB 044 wedge port heads that just had the edges cleaned up.

Thanks for all the advice, I measured the intake length from the head (where the manifold's bolt to) to the top of the stacks and was 14.5". Would you say its around another 2" to the top of the valves?

I'm going to set the timing at 30 deg, change to the 50mm stacks and have a drive and have ago with the belt off to see what happen's and i'll report back tomorrow .

Just a quick question, what RPM should i be setting the 009 at?

[Neil Davies]

When you do make the changes, do them one at a time! That way you'll know what made the difference. Pull the belt off first, then try the 100mm stacks with the 32 deg advance. Change the stacks to 50mm and leave the timing at 32 deg. Only then would I change to 30 deg, then try the 100mm stacks with 30 deg. That'll be four tests, all done without the belt so you've eliminated that straight away and are just looking at the effects of  changes.
 If you can get hold of a little point and shoot laser thermometer you can make sure the engine temps are constant too - they're quite affordable from RS or Maplins.
If you do all that you'll at least have a decent starting point for the rolling road.

[Torben Alstrup]

OK
There are a couple of things that I personally do not like. But that´s me.
Now I understand why the longer intake length helps the fuel curve. The port volume is on the high side. Normally that would result in the engine to pull high rpm but sort of flatten out say from 6 to 7 grand.
I´m beginning to suspect the cam being advanced more than normal too. Did you degree it when you installed it ?

T

[Black_65]

I´m beginning to suspect the cam being advanced more than normal too. Did you degree it when you installed it ?

I didn't build the motor (sorry), i bought it off a guy with just having the cam 'burnt in' So i just ran it in, had everything checked over and then i didn't like the set up so i had the c/r upped from 8.5 to 10.1 to suit the cam better which really helped.

Other than that info i can't help

[Black_65]

When you do make the changes, do them one at a time! That way you'll know what made the difference. Pull the belt off first, then try the 100mm stacks with the 32 deg advance. Change the stacks to 50mm and leave the timing at 32 deg. Only then would I change to 30 deg, then try the 100mm stacks with 30 deg. That'll be four tests, all done without the belt so you've eliminated that straight away and are just looking at the effects of  changes.
 If you can get hold of a little point and shoot laser thermometer you can make sure the engine temps are constant too - they're quite affordable from RS or Maplins.
If you do all that you'll at least have a decent starting point for the rolling road.

Ok, checked the timing at 32.

Went looking for a quiet road to do some testing

1st run - belt off, timing at 32, 100mm stacks : run and pulled really hard upto 6500rpm, seemed to clear better where it was holding back
2nd run belt off, timing at 32, 50mm stacks : not a 100% but i think it pulled better..! with very little struggle all the way to 7000rpm.

So i left it at that, one because i need anther pair of hands to help set the timing at 30 deg. So belt back on and drove home.

Now here's where it started to play funny with me, 2nd gear foot down and go... You guessed it, the problem came back! So on that not it must be the fan stalling at the higher rpm's where i'm i seeing it hold back and fighting to get to the max rpm.

But i've got a good ratio sorted on the crank pulley and fan with a 825mm belt but still having the issue. Doe's this mean i need to drag race it with out the belt on while im not using nitrous???

VERY LOST LOL.... 

[Shane Noone]

Hi Clarke,

You can ask Alan at GAC motorsport about the cam timing. Didn't he strip and inspect the motor for you after you bought it to check it through etc  and confirm the internals ?  Are the CB 044 wedges the CNC versions that Alan just cleaned up the sharp edges ? Also did you add the tall velocity stacks after the engine was dyno'd at GAC ?  Like Neil said, change one thing at a time and be careful if your blasting around out on the road with no fanbelt as you say you only notice the problem with engine under load. I would say carry out as many basic checks as you can before going to the rolling road to save you time and money fixing problems when you are there. Check the basics like try and make sure no leaks on fuel and exhaust side, check nothing has worked loose, check you have full throttle ok, set your timing at a nominal 30 degrees max advance with your light then you can tweak up and down probably between 28 to 32 on the dyno to see if it improves anything, check your spark plugs are in good condition and not loose. You get my drift, this sounds silly but you'd be surprised how many people get caught out and lose time at their dyno session, I include myself in that list   And if you have a selection of jets and chokes for the carbs take those along.

Good Luck

Shane.

Ps just seen your reply. The engine will always rev more freely without the fan sapping power and rev more quickly too.

[Joel Mohr]

 If it was properly dynoed, the timing total advance should be set. the curve will only affect roll-on below 3,000... is it running out of fuel?

[Black_65]

The engine wasn't split when it went into Alan's at GAC. He just fly cut the heads to up my c/r. Then he fitted the heads, rebuilt my carb'sas he wasn't happy with them and went on the dyno.

The heads are CB 044 heads that had the edges cleaned up by stateside when the motor was built but again this was done before i bought it.

He ended up fitting smaller chokes in and fitting 50mm spacers on the stacks to dial out a power issue he was having which worked. Then i just ordered the 100mm stacks from the states.

He did a amazing job TBH, where's it gone wrong is me changing things and messing the whole set up. ie. the motor was on the dyno with the old fan set up, Not the porsche fan.

I just want to play around with it before bthering Alan and putting it on a dyno....

I set the timing at 30 deg later today and really seems to like it and at idle around 1000rpm its running at 12 deg. Tomorrow i'll be looking to put back on the 100mm stack to see the difference as that's what was fitted on the 1st dyno.

TBH i think the programmable ignition box on a locked out 009 is way to much hard work with carbs. Sometimes i think just keep it simple with manual fuel from the carbs and 009 dizzy set to a good timing deg.

[PPRMicke]

The advance curve is also waaay too slow (long)
Dependant on where your throttle plates are at idle you should be at 8-11 degrees at idle. Progression should begin at 1000 - 1050 rpm. be 17-20 @ 2000 and all in between 2700 & 2800 rpm. (30-32 degrees BTDC)
When you do that you will most likely also cure, or at least minimize that flat spot in the fuel delivery, so you can reduce the intake length.
As to why it is reluctant reving, I do not know. - Are you sure your tach is right ?

A print of the dyno sheet + basic engine specifications might reveal something.

T

Should i try an re mag it using a base setting like the one above you have listed? Also sorry to be a pain but what's the difference in BTDC?

Here's the dyno print out, The AFR (black line) went abit odd as the motor before mine was on high end race fuel.



As for the tacho, I'm using a auto meter pro-comp tacho.

I'm really looking forward to plying around with it. Like i said i have a 009 in at the moment but won't take me long to change the dizzy and play around with the box and using a good timing gun

Look on 4800 rpm @ Afr 13,6 ok  and peak Tq ft 138      5000> Rpm is air jet not ok
PS Forget the ignition unless you get to the carburetors
/// Micke

[fish]

^^^^^^  x2 looks like it needs a fatter transition between main and air, but you should only be correcting that once you have adjusted your intake length, the 100mm stacks have a tendency to lean out right around the transition you are having problems with and should not have been used as a band aid to another problem in the rev range.

I would check you valve clearance, lift, duration and spring tension also and depending on your tinware arrangement, that fan will be sucking in a lot of hot air.