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Megajolt ignition map for Zetec Blacktop
Streetfighterpete - 21/1/20 at 10:18 PM

Hi guys,

Has anyone got a map download for a Megajolt to suit a 2.0 Zetec blacktop running bike carbs please? I'm using the MAP type unit with 40mm carbs off a GSXR1100. I have Kent fast road cams in it.

Any help gratefully accepted.

Cheers,

Pete


SJ - 22/1/20 at 09:00 AM

I have one saved somewhere

It's definitely on the car [2.0 BT, zx6 carbs] and should be saved on a hard drive somewhere. Let me try to dig it out.

Mine is standard cams though.


Davedew - 22/1/20 at 01:34 PM

Below is the ignition table I use with my Blacktop on GSXR600 carbs & standard cams.

MAP
MAP


johnemms - 25/1/20 at 11:19 AM

Isn't that a TPS not MAP map ?

map : manifold absolute pressure sensor
TPS : Throttle position sensor

[Edited on 25/1/20 by johnemms]


SJ - 25/1/20 at 11:30 AM

Mine's a TPS map as well


Davedew - 25/1/20 at 04:30 PM

Yep it's a TPS map.
Ignition timing would be similar, just different load scale I guess


johnemms - 26/1/20 at 03:21 PM

I'm taking my TPS Megajolt off and swapping it for a MAP Megajolt MK2
Also changing cylinder head for bigger valved head..
Then off to get it mapped on RR..
That's why I was looking at MAP & TPS ..

https://www.autosportlabs.com/product/megajolte-mk2_crank_fired_ignition/


paulf - 26/1/20 at 06:21 PM

I used too run a map based megajolt for ignition and although it was ok with a downdraught carb i found it difficult to get a smooth running map with throttle bodies using map based load. i persevered with it for a while but eventually changed to tps and found it a lot easier to map.
I think bike carbs would have the same problem in that idle has a good vacuum but once off idle thereis little resolution between part and full throttle.
Paul.

quote:
Originally posted by johnemms
I'm taking my TPS Megajolt off and swapping it for a MAP Megajolt MK2
Also changing cylinder head for bigger valved head..
Then off to get it mapped on RR..
That's why I was looking at MAP & TPS ..

https://www.autosportlabs.com/product/megajolte-mk2_crank_fired_ignition/



johnemms - 26/1/20 at 06:42 PM

I do like to mess
I've got the 4 inlets tapped (where i balance the carbs)..
Made a rail with 3 one way 4mm valves and 1 always open valve furthest away..
Description
Description


Some silicone tube & straight swap Megajolt MK2..
Looking forward to fooling about with it
If it sucks - next project will be fuel injection

A quick thought..
Do throttle bodies have a fixed venturi with just an injector and a butterfly.. where as..
Bike carbs have a butterfly but a 'variable slide' venturi which may give a better vacuum for the megajolt sensor to work with ?


[Edited on 26/1/20 by johnemms]


paulf - 26/1/20 at 10:30 PM

Im sure you will be able to get it to run reasonably with MAP but i think the carb slides may be more of a hinderance than a help as they will be another variable affecting the map signal.
I ran with a MAP megajolt with a downdraught carb and then when i changed to injection kept it to do the ignition and connected as per your idea. iI spent a couple of years playing with mapping thinking MAP load would be better, and then converted my ECU to do the ignition control as well and changed to TPS load sensing to see what the difference would be, I managed to get a much smoother throtttle response with no flat spots almost straight away.
Paul.

quote:
Originally posted by johnemms
I do like to mess
I've got the 4 inlets tapped (where i balance the carbs)..
Made a rail with 3 one way 4mm valves and 1 always open valve furthest away..
Description
Description


Some silicone tube & straight swap Megajolt MK2..
Looking forward to fooling about with it
If it sucks - next project will be fuel injection

A quick thought..
Do throttle bodies have a fixed venturi with just an injector and a butterfly.. where as..
Bike carbs have a butterfly but a 'variable slide' venturi which may give a better vacuum for the megajolt sensor to work with ?


[Edited on 26/1/20 by johnemms]