igntion/boost
Turbo Mini Forums

Just fitted mjlj and i'm ready to start writing map, can anybody tell me the max advance??????

standard engine witha piper cam and intercooler, not sure on the cr but the chambers have been opened up ( peaks removed) so should be less than standard???? Have been running 10 psi ( is this the max i should be running????

Try the search theres quite a few on here. Think i did use on of wil/ben_H maps but there are also some basic ones aswell! Best thing to do is get it on the rollers unless you have a wideband and some way of detecting for pinking!

I can't tell if there is pinking as it's on solid engine mounts

Hi,
There's only one way to make sure your engine is "safe" and get the most out of it.
That's to get it setup on the rollers to Minimum Best Advance.
Minimum Best Advance is the Minimum amount of Advance that gives the Best torque, the torque can only be measured on the rollers.
That way you're as far away from detonation without compromising power
Cheers,
Gavin :)

Edited by Bat on 5th Mar, 2008.

VEMs Authorised Installer / Re-seller. K head kits now available!

WB/EGT gauges. Click here for customers write-up

Visit www.doyouneedabrain.co.uk

My Mini build diary

start with a mety turbo adv curve and work from that:


1000 0
1500 4
2000 8
3000 14
4000 16
5000 18
6000 18

complete these numbers with advance setting (think it's 7° at 1500 rpm so top each number with 3 )

Cheers. would it be safe to drive to a RR on the base map???

Hi,
Just put Fab's numbers straight in and you'll be safe to get there.
Cheers,
Gavin :)

VEMs Authorised Installer / Re-seller. K head kits now available!

WB/EGT gauges. Click here for customers write-up

Visit www.doyouneedabrain.co.uk

My Mini build diary

Any advice on max boost i should be running

10psi on std cr intercooled is safe, then I have used up to 12 psi but this is to your own risq......a bad tank,some knows

Edited by Turbo Tel on 5th Mar, 2008.

website:- http://www.terryhunt.co.uk

cheers. I'll give it a go

"most 1276 8-10 at idle", nope
any a serie have his ignition set at 1500rpm vaccum disconnected,you make it wrong ,
I wouldn't use anything else than std ign curve before having it set correctly by a good operator who know his stuff,
failing with that and it's going to cost a rebuild, and work again from scratch.

I see what you are saying and better safe than sorry but heres a couple of pages from my Haynes. OK 1990 on says 5deg @ 1500rpm but the rest including Mpi says 8-12 degree at idle. Anyone got the actual figure for a Turbo Metro handy??

website:- http://www.terryhunt.co.uk

7 deg BTDC for the Metty Turbo in my manual. :)

WWW.TURBO-MINI.COM

website:- http://www.terryhunt.co.uk

static i use 6 DBTDC 1000 rpm vac diconected

cheked my books for confirmation:
metro and minis 80 on,
all advance are given at 1500 rpm vac disconnected ,including mety turbo
59d4, 65dm4 are set like this ,
unlike 69/72 25d4 45d4 which from haynes are set at 600 rpm
and 72/78 25d4 45d4 which are set at 1000 rpm

As usual... Utter confusion

2-3 degrees advance at idle is not normal. I would guess that this was changed to reduce emissions. Note that when the PI arrives its up at 12 degrees again! But it does change the max advance that a standard Turbo engine sees to around 21 degrees, much less than I have seen reported before. Interesting..


From my experience of federal engines I know that they used to retard the ignition at idle to reduce the emissions, specifically the HC. Normally there are small pools of fuel hanging around a carb that can cause high HC (hydrocarbons?) figures. When a pool makes it through into the engine it causes some unburned fuel in the exhaust and hence higher HC values. by retarding the ignition the engine runs slower so you must open the throttle plate a little more to maintain the idle speed. This causes a better flow of air and thus less pooling giving lower HC readings.

How do I know this? Because I spent 10 years getting my 1968 TR250 through an emissions test!! On the TR250 they went to the extreme of fitting a vacuum retard module which ONLY operated when the throttle was closed (there was a little valve attached to the throttle linkage) it caused the idle advance to retard 12 degrees to give 4 ATDC. This little valve is impossible to find nowadays but you can just run without it at 8 deg BTDC. The car ran fine BUT... I had to retard it every year to get through HC emissions

Edited by Turbo Tel on 7th Mar, 2008.

website:- http://www.terryhunt.co.uk

it doesn't have 3 deg adv at idle as there is hudge vaccum advance on the turbo dizzy,this correcting the adv curve to something more std of boost
normal as when your opening the throttle past vaccum you're on boost, on the std 9.4 this give 13/14 corrected cr , explaining why it doesn't have that much advance, and ..melted pistons when you try to tune it for max power

If the vacuum advance is higher, that makes perfect sense, still feel it was an emmisions change.. Any idea what the max vac advance was?

So given that we do not have to compromise with a MJ I'll set the idle advance around 8 degrees with no vacuum rising to 16 with vacuum. I used a max of 12 degrees vacuum advance at higher rpm's, probably less than the std Turbo dizzy but I'm not all that bothered about emissions. At no boost/vaccum I have a max of 34 degrees advance which is about right for a N/A 1275 engine but I think I will lower the on boost advance even more. maybe drop it a little quicker and at max boost (10psi in my case) go for 20 degrees.

BTW engine is 8.8 CR, with intercooler.

Edited by Turbo Tel on 7th Mar, 2008.

website:- http://www.terryhunt.co.uk

I have the advance/vaccum curve at home , will post when back.

to clarify on this map load is in kpa?
20= 80 under atm (0.8 bar vaccum), 100 is atm and 180 is 80 above, so 0.8 bar/12 psi of pressure

heres the printed off auto data sheet timing for the mg metro turbo .distributor 59dm4.

ignition timning set at 1500 rpm vac disconnected ,7 degrees.


no advance below 600 rpm
1400 rpm 2 to 6 degrees
2300 rpm 9 to 13 degrees
2800 rpm 11 to 15 degrees
3900rpm13 to 17 degrees
4900rpm 15 to 19 degrees

vacuum advance starts at 25mmhg 1 inch hg
finishes at 190mm hg 7.5 inches hg
total vac advance 22 to 26 degrees.


so a big range of tolerances there .
this ws running 4 psi to ,i think it was 4000, then 7 psi .no intercooler
and 9.4 :1 compression ratio.

regards robert

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

WWW.TURBO-MINI.COM

OK so heres a map of the standard dizzy..Pretty crap huh?



And heres a suggestion for a base map based on the dizzy spec figures..waddya all think?

Edited by Turbo Tel on 8th Mar, 2008.

website:- http://www.terryhunt.co.uk