9 replies to this topic

[liamr666]

hi, does anybody know what degrees to set a 998, 1988 engine to, i am currently timing it to 8 degrees but im not sure if this is correct

cheers

[lrostoke]

yep 8 degrees BTDC @1500 rpm vacuum pipe disconnected off the dizzy

(u)1983 to 1987 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 8º + 0º -2º BTDC at 1500 rpm
1988 (category C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 10º + 0º -2º BTDC at 1500 rpm
1989-on low-compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 8º + 0º -2º BTDC at 1500 rpm
1989-on high-compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 10º + 0º -2º BTDC at 1500 rpm

Just to add thats standard engine spec setting

Think for stage one the fitting instructions from minispares say 5 degrees @ 1000 rpm

Edited by lrostoke, 17 June 2009 - 05:13 PM.

[rajah]

Hi.

What would be the adjustment to be made to the timings shown as a result of running an unleaded head and unleaded fuel on the standard 998 engine?

Roy

[lrostoke]

The section on carbs in the Haynes manual as a bit on unleaded, and it says no adjustment to ignition timing or carberation settings is needed.

[Cooperman]

Try it at 6 degrees static, then see how it runs. It may take a bit more, but start at 6 and you'll have no problems.

Edited by Cooperman, 17 June 2009 - 08:36 PM.

[rajah]

Thanks guys.

I've just fitted a new 59D4 distributor to my 998 and set it up with a strobe light but struggled to get much more advance than about 8 deg BTDC because of the vacuum advance on the distributor fouling the oil pipe across the front of the engine.

However as it seems to be running fine (easy to start, bright on pick-up, no pinking when under heavy load, no overheating, etc, etc) it seems like adjusted to its maximum is about right.

Just interested to hear what the timing figure should be - must have missed the bit in the Haynes manual about unleaded.

Cheers

Roy

[petrolhead2047]

hi, does anybody know what degrees to set a 998, 1988 engine to, i am currently timing it to 8 degrees but im not sure if this is correct

cheers

Check you have your connections the right way round on your coil first

[Earley86]

Digging up a classic thread here.

But can anyone explain the numbers below

1989-on high-compression
- 10º + 0º -2º BTDC at 1500 rpm

I assume its 10 degrees at 1500rpm but what does the +0° and -2° relate too?

Thanks

[timmy850]

It means you can have:
10+0 = 10 as a maximum

10-2 = 8 as a minimum 

 

So set between 8 and 10

[Earley86]

It means you can have:
10+0 = 10 as a maximum
10-2 = 8 as a minimum

So set between 8 and 10

Thanks mate. Appreciate that, I have a very technical mind can fix almost anything.

Just not too good on translating the manual it appears haha.