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megajolt tuning
RMarine - 5/9/09 at 09:19 PM

i have just opened the megajolt pack for my car and in the info pack i found references to a load of set ups. please read the text below, as i need some advice on the options i have.

"MJLJ receives a PIP signal from the EDIS module, indicating current RPM, and
communicates back to the EDIS module via the SAW signal (marked as SAWPW above)
indicating the amount of advance currently required:
• For 2D, only the PIP signal is used to calculate the advance
• For 3D TPS, the PIP signal and a signal from an external throttle position sensor
is used to calculate the advance
• For 3D MAP, the PIP signal and a signal from the internally mounted MAP
sensor is used to calculate the advance.

Do i go for 2D, 3D TPS or 3D MAP ?

Pros and cons please...

blakep82 - 5/9/09 at 09:25 PM

given you've got the option for any of the 3 options, i'd go for tps 3D. (and in fact i am going to go for 3D TPS on my car)

i think its supposed to be more accurate than MAP.

2D will have relatively poor throttle response

edit: oh, actually, the build of your megajolt will determine if you can have tps or MAP. at least it used to be specific to the MJ itself. they used to be built for either map OR tps.

[Edited on 5/9/09 by blakep82]

big_wasa - 5/9/09 at 09:26 PM

Loads of posts on here. With bike carbs you will want to go Tps.

Map is beter when used with a single carb.

snapper - 6/9/09 at 07:12 AM

I beg to differ
TPS, Throttle position sensor just tell the megajolt how open the throttle plates are the advance is then calculated using that, on the MAP, manifold actual pressure system the vacuum in the inlet manifold is measured and advance calculated using the engines current needs.
TPS is probably an easier fit as the MAP system need four vacuum feeds from the individual inlet tracts, a small resovoir to even out the pulses and a take off for the Megajolt and the brake vacuum servo if you are using one.
MAP can also be configured for Turbo applications.

snapper - 6/9/09 at 07:13 AM

Oh, 3D all the time or you only get a little advantage over a distributor system

ashg - 6/9/09 at 10:22 AM

if your running bike carbs you want tps. you can do them on map but your forever be faffing around with chamber sizes.

you may get very slightly better mpg on a map sensor but it would be marginal to warrent the extra effort.

MikeRJ - 6/9/09 at 11:37 AM

quote:
Originally posted by blakep82
given you've got the option for any of the 3 options, i'd go for tps 3D. (and in fact i am going to go for 3D TPS on my car)

i think its supposed to be more accurate than MAP.


Other way around. If you have usable MAP signal that this is the way to go, since MAP relates directly to engine load. Throttle angle does not, since there is an interaction with engine RPM.

However, it depends on the induction system being used, a single carb will give a good MAP signal, one carb per cylinder doesn't give such a good MAP signal and TPS often works better.

blakep82 - 6/9/09 at 02:16 PM

quote:
Originally posted by MikeRJ
quote:
Originally posted by blakep82
given you've got the option for any of the 3 options, i'd go for tps 3D. (and in fact i am going to go for 3D TPS on my car)

i think its supposed to be more accurate than MAP.


Other way around. If you have usable MAP signal that this is the way to go, since MAP relates directly to engine load. Throttle angle does not, since there is an interaction with engine RPM.

However, it depends on the induction system being used, a single carb will give a good MAP signal, one carb per cylinder doesn't give such a good MAP signal and TPS often works better.


yeah, i know what you mean, but i'd seen his last post showing his bike carbs with tps already fitted

RMarine - 6/9/09 at 05:23 PM

thanks guys.. i think i am going to go for 3D TPS...