Supercharger Ignition Timing

[Twinky]

Hey guys, as most of you know I have recently completed a changeover to EFI.

The only failure was to have ignition control. Thus I have not attached my supercharger

fearing I would blow the motor without adequate ignition timing.

 

So my question is, what is safe timing for something like 5psi??? Do I really need to worry

for something so mild?? As far as I know the 5k electronic dizzy has little advance in it anyway.

Would it be safe to supercharge in my situation without changing ignition timing?

[kickn5k]

Lock your dizzy and wind the dizzy to full advance about 25-28btdc should be ok.(cheap)

Or I've seen a few guys on here looking at the msd programable ignition but not sure on price.

 

Stu.

[Twinky]

I think I've answered my own question I just remembered Jaycar does a programmable Ignition control kit which totals around $200.

I'll get that.

 

Linky!

 

http://www.jaycar.com.au/productView.asp?ID=KC5386&form=CAT2&SUBCATID=965#11

http://www.jaycar.com.au/productView.asp?ID=KC5442&form=CAT2&SUBCATID=965#11

http://www.jaycar.com.au/productView.asp?ID=KC5443&form=CAT2&SUBCATID=965#11

 

Looks ok, does everything I need it to do.

[philbey]

I had looked into this as well in the past; first up, there's very few people that have actually done it. I was surprised, there's a long discussion on Toymods about doing it, but I don't think they ever got down to "I did it, here are my results"

 

But I had a good hard think about buying one and combining it with an MSD 6AL to get the extra spark power etc.

 

BUT THEN: MSD revised their famous 6AL and produced a programmable version: basically combining Jaycar and the old 6AL. You can also run a MAP sensor for boost retard.

 

Long and short: but the MSD 6530 programmable unit and get it all in the one unit. About 400 bucks landed from Summit Racing

http://www.summitracing.com/parts/MSD-6530/

 

I'm in the states in January, I'll be looking to buy a couple, maybe I'll buy a spare or two and bring back.

[SLO-030]

I'll be keen if you bring one back Tom :yes:

[Banjo]

The Jaycar programable kit could be your best bet, unless you want to pay big bucks for an imported unit from the USA.

The Jaycar unit allows you to basically lock up your distributor advance mechanical mechanism, & completely recurve the advance in 100 RPM increments to suit your needs, whether turbo or naturally aspirated. It does everything the big buck profession units do, with a MAP input,or an onboard MAP sensor, plus an optional knock sensor that temporarily retards until the knock disappears.

 

There was a good thread back in March about recurving distributors. March Thread

 

I, like others, found a 5K distributor on a 4K, resulted in a poorer result, so I decided to build the Jaycar unit, and have just finished it, & have it working on the bench.

 

My aim is actually to use it as the core of a waste spark ignition system, & do away with the distributor all together.

 

I'll just have to leave the shaft in so the oil pump can run !

 

I'm using a crankshaft home made Hall Effect sensor, mounted on the bell housing, picking up a signal from a couple of rare earth magnets "buried" into the flywheel, on that land between the ring gear & the friction face. A north pole magnet fires 1 & 4, & a south pole magnet fires 3 & 2. It all works well on the bench.

 

I've just got to do some basic programming of the advance characteristics of the existing distributor, so I can get it running on the engine, which will allow fine tuning to begin.

 

The method, involves putting a degree wheel on the crankshaft pulley, and increasing the revs in 400 RPM increments & reading the advance created by the original current distributor. Would be interested to hear from anyone who has done this, because the method above sounds like a pain in the butt, if you haven't got an assistant.

 

I looked in the Toyota yellow bible workshop manual for the 4k & 5K engines, but under distributor, they don't show any advance curve info at all. I thought I might set it at the static timing of 8-10 deg at 1000RPM, then say 35 deg at 3500 RPM, with appropriate settings inbetween, and then flat/straight line it above 3500 RPM. That should get the 4K I have on an engine test bed running.

 

I'm fairly well advanced on the waste spark system, and have used a couple of old VT Comodore coil packs. It should be running within a week or so.

 

If anyone has built the Jaycar unit and fitted it on a 4K or 5K, and have it operational, I'd love to hear as to what MAP sensor they used, and where they fitted it. I was thinking of screwing directly into the manifold, as there is a threaded hole there, with a bung in it. It's where I've always fitted a vaccum guage when tuning, and it works OK.

 

If anyone is interested, I'll put some pics up of how it all goes together.

 

P.S. Actually, I spent this afternoon making a degree wheel. I looked at them on eBay, but being a 'stinge" I just Googled "Images" of degree wheels, pinted one I liked out, glued it to a thin piece of cardboard. It turned out perfect. I'll fit it to the engine tomorrow, and initially, just see how close to true TDC, that little "nick" on the crankshaft pulley is. I can see my olde timing light getting a bit of use in the next day or so.

 

Cheers Banjo.

Edited October 27, 2011 by Banjo

[Boosted]

Have they upgraded that Jaycar kit recently ? It used to only have about 12 load sites, so if you have 500-6500rpm, 6000rpm range divided over 12 load sites, is a 500rpm increment, not the 100rpm increment you're claiming.

[Banjo]

Have they upgraded that Jaycar kit recently ? It used to only have about 12 load sites, so if you have 500-6500rpm, 6000rpm range divided over 12 load sites, is a 500rpm increment, not the 100rpm increment you're claiming.

 

The Jaycar kit sets provides two switchable maps ( for dual fuel), with 11 settable load sites, or one map with 15 settable load sites. It then automatically adjusts the load site RPM increment based on the max & min RPM limits you assign.

 

I am using the the 15 load site map, and with a min RPM of 1000, & a max RPM of 6600, I get 15 sites 400 RPM apart.

 

Other combinations are . .

 

1000 - 3800 RPM 200 RPM settable load site increment.

1000 - 5200 RPM 300 RPM

1000 - 6600 RPM 400 RPM

1000 - 8000 RPM 500 RPM

 

For your example of . . .

 

500 - 6100 RPM 400 RPM settable load site increment.

500 - 7500 RPM 500 RPM

 

However, the microprocessor then creates three more "calculated" sites between the settable load sites.

It basically takes the difference between the advance at two consectitive "settable" load sites, and divides that by 4, which becomes the final load site increment.

 

In my setup with 1000 - 6600 RPM the settable load sites for 3000 & 3400 RPM have advances of say 25 & 29 deg assigned respectively. The calculated load sites for 3100, 3200, & 3300 RPM would be assigned advances of 26, 27, & 28 deg of advance, by the micro processor.

 

If I set the maximum RPM to 5200, I obtain increments of just 75 RPM.

 

Even at 500 - 7500 RPM the load site increment would be 125 RPM.

 

In this way, using a 15 load settable map, you actually finish up with 57 sites created,over the entire rev range you set.

 

 

Cheers Banjo

[philbey]

The Jaycar programable kit could be your best bet, unless you want to pay big bucks for an imported unit from the USA.

 

I'd hardly call 400 bucks, landed, expensive :lolcry: . This is how I looked at it: 200 for the Jaycar kit. 10 hours to build it at 20 bucks an hour (It'd be more like 100 hours for me in reality) that's 400 bucks. Plus you get the extra spark grunt of the MSD.

 

I actually want two MSD's, one for the rolla and one for the 911, the yankee 911 owners get good results from them.

 

Having said that, I am very interested to see what you build Banjo, sounds like an interesting setup.

[ke70dave]

if you are going to build that jaycar kit...just buy a MS1 megasquirt.

 

i think they are only about 250us now. come with a map sensor (3bar?). just need to read a fair bit about how to set it all up. but hey thats why its a hobby?

 

then you get to control the fuel as well in one unit. Btw what are you controlling the fuel with now?

 

edit:

 

http://www.diyautotune.com/catalog/megasquirti-programmable-efi-system-pcb22-kit-black-case-p-128.html

 

only 153usd!

 

just have to check if that includes your map sensor...if not they are fairly cheap.

Edited October 27, 2011 by ke70dave

[kickn5k]

if you are going to build that jaycar kit...just buy a MS1 megasquirt.

 

i think they are only about 250us now. come with a map sensor (3bar?). just need to read a fair bit about how to set it all up. but hey thats why its a hobby?

 

then you get to control the fuel as well in one unit. Btw what are you controlling the fuel with now?

 

edit:

 

http://www.diyautotune.com/catalog/megasquirti-programmable-efi-system-pcb22-kit-black-case-p-128.html

 

only 153usd!

 

just have to check if that includes your map sensor...if not they are fairly cheap.

 

See now that's the idea. If your not good at electronics, try a second hand "name brand" ecu. I got my haltech with enough bits to run coil per plug full sequential ignition and fuel for $450(just need to make the CAS). That included 4 coils and ignighters.

 

Stu.