Tacho booster- 1GGTE / MA61

[Admiral coFF33]

Hey all

so i built the tacho booster that INFOTECHPLUS has a thread about... that the witzl etc posted in.

Anyway

on my MZ11, and i know "blair" with his 1GGTE Celica is having the same issue.

The tacho, works, but ,

When at idle shows ~1.200rpm
at 20kph in 1st shows 4000rpm
at 45kph in 2nd shows 4500rpm
at 60kph in 3rd shows 4000rpm

travelling on the highway at 100kph, Diff = 4.1, W55 , 1GGTE

tacho shows 4200rpm for 100kph, the car does NOT sound like its struggling.


If ive run the same setup as the tacho booster thread, then what could be wrong with the one i have made causing it to run higher than usual?

or is the one in the tacho booster thread only for 7MGTE ignitors?

cheers

coff

[big_zop]

Firstly, do you know if your speedo is reading correct due to any changes in diff, gearbox or tyre size?


We also need to know your tyres size to work out engine rpm (I figure its 195/60/15 from the last update to your thread so have based my calcs on that)

20kph in 1st shows 4000rpm - 2509rpm (59% higher)
45kph in 2nd shows 4500rpm - 3254rpm (38% higher)
60kph in 3rd shows 4000rpm - 2920rpm (37% higher)
100kph in 5th shows 4200rpm - 2990rpm (40% higher)

Apart from 1st gear, it would seem that your tacho is reading about 40% higher than actual but I would make sure your speedo is accurate before trying to change anything else.

[Flex]

I've noticed a lot of people are having trouble interfacing tachos when doing engine conversions. I wondering if there is a need for retro fitting tachos? i.e. replace the guts with new one that works with the new engine set-up

[CrUZida]

Tacho booster should work properly if installed as per the directions.
Nathan used one on his 1GGTE GA61.

Your tacho is reading roughly 35-40% high across all gears.

Did it read correctly with the old 5MGE?
Grab another tacho (autometer or such) and see what it says.

'blair' will the error because he has a 4cyl dash and a 6cyl signal.

[Admiral coFF33]

the old tach with the 5MGE that was in there worked fine.
the speedo reads ~2-4kph slower than what it should be had to get that correct or i couldnt pass inspection over here when i registered the car. (trialed and tested by local enforcement)

id say that the tacho booster ive made is IDENTICAL to what witzl made in the INFOTECHPLUS thread.

Im going to get an after market to test as soon as i can, but i know for a fact (engine noise when shifting) that what my tacho is reading is incorrect. by ~1000-1600 RPM

i might just make another booster and put it in using brand new relay from supercheap and see if that fixes it.

[mullett]

i might just make another booster and put it in using brand new relay from supercheap and see if that fixes it.

Well, there's your problem Go get a real relay

-RM

[Blair]

Yeah mine was all out bad lol.

Thinking about aftermarket cluster setup though, so might not worry too much.

[Admiral coFF33]

Robin :
surely relays cant differ
arnt they all made the same ?

[CrUZida]

There are different relays, as some of the bosch ones have different part numbers on them.
How they differ I have NFI though.

[RA35GT]

Some relays have a diode or resistor across the coil to remove/reduce the induced voltage in the coil when the relay is turned off. (To protect the computer/whatever is switching it)

(Obviously this would make these type of relays either work crappy or not work at all as a tacho booster).

These relays usually say on the packet or themselves though.

[Admiral coFF33]

where to get a relay then that shouldnt have this resistor embedded in it.???

Jaycar or the like im guessing ?

[RA35GT]

Anywhere that sells relays man, they usually have all the different types. Just gotta make sure there resistor/diode isnt listed anywhere on the packet.

For Narva ones, try to find the following part number.

Part No	Blistered Part No.	Volt	Amp	Pin Type	Current	Draw (Amps)	Protection 
68024 	68024BL 		12V 	30 	5 		0.14			- 

Part No	Blistered Part No.	Volt	Amp	Pin Type	Current	Draw (Amps)	Protection 
68000 	68000BL 		12V 	40 	4 		0.14 			-

The easier option is to just open up the relay you have and make sure there is nothing connected across the coils.

Also, I'm not sure if that is your problem, you might want to try your booster in another car and see how it operates there.

[Admiral coFF33]

could try it in my housemates 1GGTE GZ10 i guess....

i think ill go build another couple of them and test on both our cars.

just that thread about how to make them, everyone mentions 7MGTE and nothing about 1GGTE.... so im starting to wonder if the output from 1GGTE ignitors are different to 7MGTE and thats whats happening with the revs..

oh well when i got some spare time ill make a few and post results.

[CrUZida]

. .

nathan used one on his 1ggte ga61.

[Admiral coFF33]

..........

i dun read thing good?