Megasquirt on dx motor. Worth it??

I'm having issues with my k-jet rocco. Its a bog standard motor apart from the cam.
I've already thrown400 at the fuelling but its still not right. Ideally i'd be wanting to renew the lot as its high on emissions, lumpy running, revs up and down like a hussys knickers, pinking....in short its right peeing me off.
So, i thought rather than try and sort the standard set up, i'd venture into the world of "aftermarket ECS".
So, questions are:

1. Economy....will this plummet with something like megasquirt?
2. Can a complete biff like me sort it or do you need to be an electrical genius?
3. Whats a rough estimate of a full system, up and running?
4. also, i'm not arsed about 0-60 in 7.7 sec's, i just really want it to be reliable...any performance gains are purely a bonus.


Taaaa

 

If it's a vac leak, headgasket, burnt out valve, etc the MS will not help much... MS will probably loose you some throttle response, but gain a little power. If that is, you spend the time setting it up properly, which will involve a wide-band lambda probe or a RR session. Both of which on their own will probably cost you more than sorting your current problem out (once you've found it).

You can learn a lot from MS for future projects/more power if you're interested. If you're not interested i wouldn't bother. It's deffo not one of the easiest or cheapest fixes for your problem.

 

Yep if it is a hardware problem then the use of a SEM is of no benefit. Fix the hardware.
On the other hand the use of a stanalone can actually improve the response of the engine leading to WOT loads and still maintain the high load torque curve if it were so optimised on Kjet or even improve it due to a greater adjustment window ( what calibrators like to refer to as having more "knobs"). This is not limited to MS and you do not need a dyno to make certain changes. Lambda kit is required for self tuning as correctly stated. These are not that expensive and are benefical for any type of fueling adjustment including K-Jet diagnosis.

Time and cost is dependant on user skill and know how but may agree that this particular case sounds to a work around to a non related issue.

The advantage of MS is the cost, providing you have reasonable know how. In this case the cost and effort maybe underestimated without establishing a good baseline on existing hardware.

 

Well the guys i took it to at Leeford Bosch had all the gear RJ. The pressure was low, if i remember correctly it was about 2.0 bar. They replaced some poxy little rubber washer in the fuel distibutor and got it back up to the right fuel pressure but, they said they coiuldnt get the emissions down..?? Well how the heck can a "specialist" be unable to do that??
Anyway, it seemed a fair bit better than it was, now however, i have the "pinking" issue when i'm setting off in first and if i'm on motorway sat at around 70 and i accelerate, it pinks then as well.
I know K-Jet is a decent set up when it right but i'm a bit pee'd off with it to be honest.

 

Hve you checked the coarse filter (gauze) in the fuel tank swirl pot? Fuel pressure may be ok at tickover, but drop off under load if there's a problem with the system.

Have you checked the spray pattern and dilivery quantity of the injectors, as per haynes?

The air flap arm in the metering head could be bent, there's a guide on setting them up somewhere...

Have you done a compression test?

 

Will check the gauze but the guys at Leeford reckon the pressure was good. I'll check anyway.

Brand spanking new injectors.

I'll dig the guide out.

Nope...but i will now you've mentioned it.

 

Ok,i think the best option here is to have the fuel system checked out again by a proven tech centre or a chap with the gear and the know how.
Is there anywhere that fits the bill and has been tried and tested?
Also i'm up in West Yorkshire so the nearer, the better. I will however travel for a place with a proven record of success at fixing k-jet. Bit desperate now. Whilever its pinking, its not doing the motor any good really.

Cheers for all the info and help so far chaps.

 

You'd be better off investing time and funds into you own (pressure)test equipment. Or borrowing a set, just pay someone on here the postage... There's loads of info about how to set K-jet up on internet. The bosch manual is even online, on here prob...

 

Ok gents, I'll take your word for it and look into getting my own gauges. What do I need to buy to cover the system? what gauges and do I also need a gas tester? what other gear do I need?

 

you need a pressure gauge, upto 100 psi and a T in the fuel line to the metering head, i used some scrap banjo connectors of an old metering head so i could replace one fuel line with my piece with the gauge in it. TBH there's a lot of checking you can do before you get to that stage tho... like measuring the rest place of the air flap. I'd get the manual and set up the flap first. But then, before that i'd check the basics like vac leaks, engine compression, fuel gauze, throttle setup, etc.

 

Cheers Mark.
The guys back at Leeford Bosch reckoned i had no vac leaks but i'll check it out anyway. Can of carb cleaner sprayed around pipes give an indication doesn't it? Engine speed drops?
I've got a compressionj tester so i'll do that as well as the other stuff.

 

Hmm... your pinking could be a sign that the dizzy is worn and advancing too far, although I think it's likely you've still got a fuelling issue too.

Kjet is too old school for most 'experts' these days.

I've had great results from Megasquirt (from 136 up to 150 bhp on a modded 2.0 8v) but I don't think it's necessary on a standard engine. If you were sticking a head and lumpy cam on it, I'd say go for it.

If you buy a built ECU and pay someone to help you map it, you won't get much change out of 800-1000, assuming you buy the additional bits (injectors, fuel rail, TB with TPS, sensors, fuel hose, air filter/box/intake pipe, wiring bits) at scrap yard prices where you can, and spend a bit of money on new tools like decent crimpers and a gas soldering iron.

Borrow a wideband lambda unit if you can, to get a good idea of what's coming out the back of your exhaust, including full load running. I suspect you might be running rich at low revs but running out of fuel at the top end. It's a common problem with Kjet.

Having said all that, I'd recommend you go in the following order. I'm assuming you've already done the obvious stuff like checking the air filter, changing the fuel filter, plugs, rotor arm, etc.

1. Check cam timing.
2. Check compression
3= Check ignition timing (and how much it swings at higher RPM)
3= Check mixture / fuel pressure at tick over to full load running.

The pressure gauge recommended already would then tell you if you've got a drop in delivery pressure coinciding with your higher demand for fuel, or if the pressure stays steady, it's more of a WUR/Metering problem.

 

Thank you. 50/50 and i drop a ball.

 

Thanks Mike.
done most of the obvious stuff.....only thing i've not changed/checked are ign leads and coil.
I'm going to take a couple of days off work to try and sort this once and for all.

 

Just remembered, if you make the pressure gauge setup you'll need a shut off valve in that section of pipe too.