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14 Degree Timing

8880 Views 30 Replies 20 Participants Last post by  Spunkey the Monkey
What's this all about... and should I do it?

Seen some stuff but nothing in basic english that tells me simply what it is and why I should maybe do it?

Thanks
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from what ive read on here and "remembered" (so I could wellbe wrong)...

the 5 comes out of the factory with timing advanced 10 degrees (from wherever it would be if it weren't). You advance it 4 more using a "thing" and in theory you get a bit more grunt lower in the rev range at the expense of some at the top.

I think.

something like that anyway
That's about right, the Mk1 5 left the factory with timing set to 10degrees btdc, you can change this to 14degrees which should give slightly more torque lower down the rev range (where you're more likely to use it in an everday driven car).

The actual difference it makes is minimal, but it's free and easy to do, you just need to put a jumper wire between Gnd and Ten in the diagnostics box and then get a timing light on the crank pulley (you'll see the timing markings down there), and just move the cam angle sensor slightly until the timing is at 14degrees. I got a garage to change the timing whilst the car was in there having some work done, took the mechanic a few minutes to to.
The idea behind this is that the vehicle is made for various markets with lower octane fues (much lower than ours) the lower the octane the quicker the flame front (opposite to what you may logicly assume). As a result you'd be safe to increase the timing from 10 to 14 degrees thus optimising peak expansion and torque based upon a typical uk octane fuel. Without risk of detonation.
The idea behind this is that the vehicle is made for various markets with lower octane fues (much lower than ours) the lower the octane the quicker the flame front (opposite to what you may logicly assume). As a result you'd be safe to increase the timing from 10 to 14 degrees thus optimising peak expansion and torque based upon a typical uk octane fuel. Without risk of detonation.
Running 18 deg on mine with Tesco 99 RON. No problems so far but I am fully prepared to knock this back to 16 or 14 when the warmer weather arrives.
The idea behind this is that the vehicle is made for various markets with lower octane fues (much lower than ours) the lower the octane the quicker the flame front (opposite to what you may logicly assume). As a result you'd be safe to increase the timing from 10 to 14 degrees thus optimising peak expansion and torque based upon a typical uk octane fuel. Without risk of detonation.
Running 18 deg on mine with Tesco 99 RON. No problems so far but I am fully prepared to knock this back to 16 or 14 when the warmer weather arrives.
[/quote]
does it feel much different? heard that past 14 degrees doesn't make a huge difference? planning to advance my 1.8 when i've found a timing gun...
The idea behind this is that the vehicle is made for various markets with lower octane fues (much lower than ours) the lower the octane the quicker the flame front (opposite to what you may logicly assume). As a result you'd be safe to increase the timing from 10 to 14 degrees thus optimising peak expansion and torque based upon a typical uk octane fuel. Without risk of detonation.
Running 18 deg on mine with Tesco 99 RON. No problems so far but I am fully prepared to knock this back to 16 or 14 when the warmer weather arrives.
[/quote]
does it feel much different? heard that past 14 degrees doesn't make a huge difference? planning to advance my 1.8 when i've found a timing gun...
[/quote]
My 1.6 was running 18deg on super unleaded before i fitted the blower. It felt torquier, lower down the rev range than when it was at 14 deg on normal unleaded. I found it better for every day driving than having all the grunt at the top of the rev range.
That was my feeling anyway!
Bert
The idea behind this is that the vehicle is made for various markets with lower octane fues (much lower than ours) the lower the octane the quicker the flame front (opposite to what you may logicly assume). As a result you'd be safe to increase the timing from 10 to 14 degrees thus optimising peak expansion and torque based upon a typical uk octane fuel. Without risk of detonation.
Running 18 deg on mine with Tesco 99 RON. No problems so far but I am fully prepared to knock this back to 16 or 14 when the warmer weather arrives.
[/quote]
does it feel much different? heard that past 14 degrees doesn't make a huge difference? planning to advance my 1.8 when i've found a timing gun...
[/quote]
My 1.6 was running 18deg on super unleaded before i fitted the blower. It felt torquier, lower down the rev range than when it was at 14 deg on normal unleaded. I found it better for every day driving than having all the grunt at the top of the rev range.
That was my feeling anyway!
Bert
[/quote]

Good stuff. Think since the K&N went on it's maybe got a dip in the torque curve low down, so this sounds just the ticket. I normally use 99 RON but wouldn't want a timing setting that couldn't cope with normal super unleaded when nothing else available.
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[does it feel much different? heard that past 14 degrees doesn't make a huge difference? planning to advance my 1.8 when i've found a timing gun...
Feels nippier to me on part throttle and at lower engine speeds. Useful for the hilly areas where I live.
You advance it 4 more using a "thing" and in theory you get a bit more grunt lower in the rev range at the expense of some at the top.
Sounds like a sensible option
Where would one acquire said 'thing'?

Cheers,
Timing gun, pretty cheap from most tool shops online
You advance it 4 more using a "thing" and in theory you get a bit more grunt lower in the rev range at the expense of some at the top.
Sounds like a sensible option
Where would one acquire said 'thing'?
[/quote]

:lol:yes, the "thing" you need is a timing light/gun which you can buy from just about any auto/tool store, even Halfrauds.

Honestly, it really couldn't be any easier. If you don't want to lay out the £££ for a timing gun then ask your local garage to do it for you, it shouldn't cost much at all as it's only a 5 minute job.
I've never noticed any difference on a 1.6 and on a 1.8 it tends to adversely affect the top end.

Anyone got any dyno evidence before and after, particularly for a 1.8 ?
I've got some dyno printouts somewhere, but it shows my stock 1.6 and then the same car with decat & the 14 degree timing mod.

I'll see if I can find them...
I've got some dyno printouts somewhere, but it shows my stock 1.6 and then the same car with decat & the 14 degree timing mod.

I'll see if I can find them...
Did those 2 mods make any difference?
I had this tweak done to my 1.8 today (cheers Halli), and it does *seem* to make a small difference, particularly low end reponsiveness on part throttle, and feels slightly punchier in the midrange, I've not really noticed too much of a deficit with the top end - still feels much the same flat out, but then I always felt the 1.8 gets a little out of breath towards the red line anyway (this is especially noticable considering my previous car was an Integra Type-R!)... overall I'm pretty happy with the compromise, but it is a small difference.

Obviously though I have no figures to prove it, so I could be imagining things!
I've got some dyno printouts somewhere, but it shows my stock 1.6 and then the same car with decat & the 14 degree timing mod.

I'll see if I can find them...
Did those 2 mods make any difference?
[/quote]

here's the dyno sheet....



Red line = stock 1.6 Roadster with a Magnex cat-back system.

Blue Line = same car but this time with a Magnex decat-pipe fitted and the 14degree timing mod done.

As you can see it does make a small difference, there isn't much in it. I couldn't physically tell any difference tbh, it's just that fitting the decat pipe made it a bit noisier, so it sounded faster:lol:
but the timing mod is easy enough to do.
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On the one hand, I'm surprised at how little difference the mods made but even so, 118bhp from an 18 year old 1.6 is still pretty impressive.
In my experience, the timing advance trick makes a noticeable difference.
I'm perhaps the least techy person on this Forum, but from personal experience all I got was pre-ignition (pinking?) in hot weather and no appreciable benefit but it co-incided with decatting and an SS exhaust being fitted. I disturbed the CAS seal which unknown to me till it was too late, promoted an oil "mist" over the heater pipes entering the bulkhead. This finished them off resulting in a spectacular geyser of coolant. Old seals don't like being tweaked & for around £2.00 I sincerely advise popping a new one on especially if the heater pipes are original and "tired" Apparently I'm not alone in disturbing this seal and paying the price.('94 1840cc)
All the nay-sayers seem to be 1.8 owners, so maybe advanced ignition timing has less benefit on that engine? If you have advanced beyond 14 degrees and you are experiencing pinking then super-unleaded is probably required.
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