Autosport Labs

That's exactly that!
With low rev limit and only soft rev limiter, my exhaust used to experience loud Bang when hitting max rpm so don't be surprised if it happens.

To start, try with conservative timing.
Let say 15° at idle and 30° at 3500rpm and up.
Make a linear plot from those 2 points and get you first map. This is how I've done mine and it is not finished yet but I've always been on the safe side.

You could check my topic with my Z where I've shown map evolution. I've started with timing similar for a given load to reproduce distributor curve with no vacuum correction until power was good at WOT. I then looked at map zone were I was cruizing under low load (3200rpm & low load), I increase...

I'm trying to make sure if something goes bad in my system, I can still drive the car home safely. My TPS sensor is plugged on carbs linkage, wires are running close to heat shield which is sharp, exhaust headers that are running hot, etc. This is a very hostile area that could lead to failure. Same...

Hi Klaus,
Thanks for the tip
I'm already following this group. There's some good knowledgeable people for sure in it.
I'm trying not to bug them as long as I haven't tried my solutions first.

Some people use also other coil packs that are not from Ford vehicle. As long as there's no drivers, impedance is equivalent to Ford coil pack, dwell is ok, it could work. They are using on 6cyl version, Chrysler coil pack because it uses regular spark plug connectors, it is also flat, so easier to ...

Hello Alex, You're right, Chokes are inserts I can switch. Size range would depend on DCOE size (40 mm in my case) You're also right regarding the mixture becoming lean when going bigger on chokes without altering other jets. I'm my particular case, I've got tons of jets so I can play with them to m...

I'm still looking for the lean spot root cause. I've been able to go WOT for many seconds in 4th gear whereas lean spot can be observed in 2nd gear. Fuel supply is not the root cause. I've played also with timing, it hasn't changed anything so timing is also out of the way. It remains carb tuning &a...

I need to check that and see if I can increase timing at low load. On a side note, I've checked AFR and I need to address some very lean conditions at WOT before messing up with high rpm if I don't want to make my engine explode. I don't know what makes this situation: carb tuning, chokes too small,...

Got it!
At cruising speed, I'm more around 2500-3000 rpm but situation is the same. I'm at 40° max with 34° total advance at high load / high rpm, I need to check how far I can go and your example make me believe I could do it.

How did you end up with +50° for low load? Trial & error? I'm in the same boat (car I should say!), I keep increasing timing at low load and see if it helps. Dyno (braking unit, not inertia) seems to be the right tool since we could measure torque output versus timing at any engine state to fine...

How does your engine run? Have you done the map on a dyno? I'll interested to hear about you. You've got ton on timing advance at low load. My engine is nowhere near yours but I'm trying to see how far I could go as well with mine. The curve are not so smooth, I mean you've got major steps in your m...

Thanks! :wink: Weather was very nice, I've been able to play more with MJLJ today. I've increased max timing as well as timing under load. Car is much more powerful than when I started. It is becoming too fast to check everything properly on open roads, even with rev limiter set at 5000rpm :roll: So...

I had a lot of fun today! 3 hours driving the Z in forest roads was fun. Especially when the car runs great! No issue at all! First, I was able to reproduce the BANG, it is coming for sure from the soft rev limiter. So there isn't any worries there anymore Then, I had plenty of time to play with tim...

you can also connect a external MAP sensor to TPS wires, get the calibration from the MAP sensor and go with it. Not as clean as integrated MAP sensor but easier to do... Brent mentioned it somewhere on the forum. I've got TPS to MAP conversion hardware also, not sure if I would use it one day... :r...