Varajet II

[bang_chong]

Hi guys just purchased a varajet II off the net to replace the one on my VK. Noticed that the new carby is slightly different as it doesn't have a throttle postion switch. My question is what do I do in regards to this switch? Is it needed?

[codfishface]

I reused my existing one. It's just a simple micro switch, easy enough to test it.

IIRC, it lets the EST module know when the engine is off idle. I've since junked my EST, so have removed it again.

[VK SL 3800]

If you still have EST its needed otherwise the computer gets confused with the readings it gets, pretty sure it is an open circuit at idle then connects when you accelerate. Mine needed adjusting and sometimes would trigger limp home mode under really light throttle because it would see the manifold pressure drop and engine revs increase as though you accelerating but not get the signal saying you have opened the throttle making it get confused.

[bang_chong]

Yeah i found out its off a VH explaining why it doesn't have the switch. Anyone know how I could rig it up too have the switch? Whats involved in removing the EST?

[ari666]

change the dizzy. its easy and worth it

[bang_chong]

sweet well what dizzy you think?

[codfishface]

Time to do some research, bang_chong.

If, as you say, the reco carb came from a VH, this is a good thing if you change the distributor. It will have the vacuum port for the vac advance already there.

Atm, with Electronic Spark Timing controlling your spark advance, you have a control module in the passenger side kick panel that does all the number crunching to decide your spark timing. There are also four sensors to help it. By swapping out the EST dissy with a unit from an earlier model (blue motor) you will have control over your timing and can disconnect the module and sensors.

I bought a reconditioned/regraphed (for 98 octane) blue motor dizzy for $200. The improvement on economy and power was amazing ~ 30% easy. Before the reco one, I tried a fiddy dollah ePay one, but it was ass and had seen better days.

[bang_chong]

Yeah mate done a little bit of research mate. Just wanted to get a part number or name on which dizzy to use. As ive read also do I need to change my coil aswell?

[ari666]

yeah, get a bosch MEC715 coil for 70 bucks and an ebay dizzy. think this one, but not 100%: NEW ELECTRONIC DISTRIBUTOR HOLDEN 6 149 161 179 186 202 - eBay Distributors, Ignition Systems, Car Parts, Accessories, Cars, Bikes, Boats. (end time 08-Jul-10 18:27:54 AEST) for 90 bucks

[bang_chong]

The improvement on economy and power was amazing ~ 30% easy. Before the reco one, I tried a fiddy dollah ePay one, but it was ass and had seen better days.

When you mean $50 dollar, do you mean second hand or new from the ebay store? And really is the improvement that much.... wow any improvement on fuel economy must be good lol. I heard after changing the dizzy and coil all thats left is too disconnect the computer, is that right?

And ARI666 Ok thanks mate. Yeah just had a look at this before but got turned off because I got mixed up in title(thinking electronic meaning EST).

Appreciate the info guys. Oh and is it alright to swap my carby before I swap the dizzy and coil and drive it around for a bit? Will it affect the car dramitically or will it be fine?

[VK SL 3800]

You will get power gains but just dont expect to be thrown into your seat dude, after all, its still gonna be a Black motor. As for fuel economy it wont be anything spectacular and may or may not improve, my EST gets between 8.5 to 10.0 liters per 100km on highway and around 13.5 round town so its not as though its really crap to start with if its all working right. But do the conversion as with your Vh izzy you have the proper port for advance, original VH motors have Thermal vacuum switches to give advance at idle when its running hot and one that only allows advance when the engine warms up a little so it wont addvance at all cold but these are not necessary to run.

[codfishface]

$50 dizzy was a second hand jobbie.

My increases were mainly due to my EST system being functional but well past it's use by date. I believe the EST was introduced mainly to control emissions, therefore the timing curve was pretty bland and restricted. I've recently installed a reco EFI head that has been shaved, ported and fitted with heavy duty valve springs. My fuel consumption is much the same as VK SL 202's, but I haven't had the chance to take it for a decent run yet. Crow Cam and new lifters will be next.

That dizzy ari linked to looks the goods.

[ari666]

yeah the only thing with the those ebay dizzy's, i have said it once and ill say it again; CHANGE THE HEI UNIT. lol. a lot of people dont think its worth it cos they plug in the dizzy with the chinease unit and it works so they think its ok, but it WILL cause problems down the track that will be really hard to pin-point. genuine bosch hei units are relatively cheap and will last 50 years.

[bang_chong]

haha I don't expect a 202 to ever throw me back in my seat, just was more interested in the better fuel economy. Plus my carby really needs a swap as it has some serious issues and I didn't want to have my car inactive for no longer than a weekend. Will let you know how I go