Melted Piston.

ECU

lookforjoe said:
About 300 miles on it now. Can't really thrash it yet, 'cos I have engine management issues. AFR's are great under light load & cruise/idle conditions, but definitely too lean if I try to get on it, so really haven't.

I've tried raising fuel pressure, fattening up the MAF output, but it's not really helping. I don't seem to have any acceleration enrichment. All the MAF functions check out.

I think I need to get injectors that are matched to the MAF/ECU - which means 20lb/200cc, instead of the 17lb ones I installed.

Volvo used composite 200cc (0280155746, yellows) on the NA V70, and 230cc (0280155702 blacks) on the some 960/V90 models. I'm going to see if I can locate some locally to try. I don't want to go too large, since that will require dropping the base pressure, which I believe can have a negative impact on fuel atomization. I have some 300cc (0280155759 reds) injectors, but that would mean dropping base pressure at least 20% to get them in the ballpark. I will need 1/2" spacers for the fuel rail, since all these injectors are longer.
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Hi Hussein,

I'm sorry to hear that you are having issues getting the Bosch LH 2 working well. I suppose that was always going to be the case given that you have a non standard ECU combined with a non standard engine.

One option (just for troubleshooting) might be to revert to L-Jetronic, just to see how the car runs and to take some measurements that might help with the LH 2 tuning. Alternatively, given that you are using a Tipo head, I noticed that Tipos either used a single point injection or a Bosch Motronic ECU (e.g. http://articulo.mercadolibre.com.ar/MLA-522884087-centralina-de-inyeccion-ecu-fiat-tipo-16-mpi-bosch-_JM.

Here is also some information (from a company that makes after market ECUs for LPG applications) about the stock ECUs for various Fiat models:

http://www.tempra.org/ttt/schematy/landi.PDF

I do understand that this may mean swapping out the wiring harness and is not a quick swap but it shouldn't be too complicated to do a temporary installation just to see how it goes.

Sometimes a complete swap can reveal more than iterative troubleshooting on a specific part (I've been there many times!).

Anyway, just an idea (although I do realise that I was lobbying for you to install the LH 2 in the first place!).

Cheers,
Dom.
 
I feel your pain mate!

I thought sorting out jets, emulsion tubes and choke sizes was tough.

Which I'll have to do with the new engine...
 
Thanks for the links, Dom.

It would be far more work reverting to L-Jet than the minor issues I currently have :)

It's really just a question of getting the correct flow rate injectors - the system was designed to work with 200cc, and the problem lies in the fact that I could not use the Saab ECU, which was programmable. It's a relatively minor issue, since the system works well overall and is drivable, I just can't thrash it the way I'm used to doing yet :)
 
Hey there... I just now found this thread as...

it ran off my screen and I didn't see the updates.

One thing I think you may be missing here... You went from a 8.5 or 9.5 CR up to a 10.7... That alone will most likely require an Octane Additive... given today's gas. We have 91 Octane here in CA, I imagine some states still have 93... but that still won't support a 10.7 CR on most engines.

Congrats on getting it this far though, especially with all the mods. I think you might haveta BITE the BULLET and get yourself an MSD type ignition system with all sorts of digital advance controls as well as a rev limiter. I was kinda disappointed to hear the one you now have doesn't have either of these features.

Looking forward to seeing more of your exploits!
 
Black-Tooth said:
it ran off my screen and I didn't see the updates.

One thing I think you may be missing here... You went from a 8.5 or 9.5 CR up to a 10.7...

Congrats on getting it this far though, especially with all the mods. I think you might haveta BITE the BULLET and get yourself an MSD type ignition system.

Looking forward to seeing more of your exploits!
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Thanks, Tony

93 octane is readily available, and seems to be OK with slightly retarded advance settings.
Having a decent AFR seems to be the main problem - timing is of course a factor', which should be resolved once I get the Volvo/Bosch system in place which has knock control, etc. One of the big features is ignition advance at idle when the cooling fan is running - that will help offset the crappy flow through the stock pump at low rpm. Right now I have to run less advance, which is increasing temps at idle, even with the decreased vane clearance I set. Once moving, needle stays below center most of the time.
 
I see, I see...

I assume you have two fans running in parallel to cool the radiator... and a reasonably new t-stat at 185 or so.

If you are still purging air outta your radiator... then you must have another fine leak somewhere also.

After all that you might TRY an axillary pump that fits on one of the hoses and is thermo-controlled to switch on to move more coolant during idle.

325312_x800.jpg


They look something like this...

Of course, you cam also flow too much coolant when running... but this should help at idles if you car runs cool at speed.

HTH...
 
If you have a place to mount it in the intake plenum, maybe you could somehow rig up the old LJet cold start valve as a way to squirt more fuel in at or near WOT. If the AFRs don't lean out so much, that would be proof of concept that more fuel is needed than can be delivered by your current injectors.

For experimentation purposes you could put it on a toggle switch and manually activate.
 
Black-Tooth said:
I assume you have two fans running in parallel to cool the radiator... and a reasonably new t-stat at 185 or so.

If you are still purging air outta your radiator... then you must have another fine leak somewhere also.
Click to expand...

Yes, and no - no more air. Part of my bleeding troubles were that I had the heater valve circuit closed :roll eyes:

I want to avoid extra pumps, etc. I'm confident having the more sophisticated timing control will resolve many issues.
 
Dan Sarandrea (Phila) said:
If you have a place to mount it in the intake plenum, maybe you could somehow rig up the old LJet cold start valve as a way to squirt more fuel in at or near WOT. If the AFRs don't lean out so much, that would be proof of concept that more fuel is needed than can be delivered by your current injectors.

For experimentation purposes you could put it on a toggle switch and manually activate.
Click to expand...

Not a bad idea. CS valves are very coarse in terms of flow/atomization - I did do something like this on my old 245turbo with Nitrous back in the 80's - engaged the CSvalve over a certain boost level when the nitrous (with fuel fogger) was active. It definitely helped, but was really hard to control.

I'm going to start with the 200cc injectors. I picked up a set of both 200cc & 230cc injectors.

A3DB63EC-A0BF-4D50-AD82-F05612135F69_zpsvjuzodjw.jpg
 
Both sets I brought home were dead. I installed one set, and no start, so I pulled them back out & tested them right off the battery - no click at all from any of them. Went back to the shop & found a set of Volvo 850 NA injectors still in the manifold. They all passed the click test :)

The great thing about the new setup is that the injectors and complete rail can be removed without removing the plenum - makes life much more manageable.

With the replacement set, the engine fired right up. I dropped the line pressure to 43psi (base), and leaned out the MAF output to 1.5v.

Now, when started cold, I have AFR's in the 13's, which is more appropriate for warmup. Once warm, the AFR's are still in the 14.3-15ish range, and the system O2 is sweeping appropriately.

I finished up too late to take it out for an under load spin, so I'll be doing that tomorrow :excited:
 
Better, but still lean under load. I need to mark the crank pulley for 30º BTDC to check the advance on the Computronix ignition, until I get the EZK components all sorted out.

I have the harness mostly built (not the piece in the pic), and cut a hole in the right bulkhead to pass the harness through.

DA9F7586-5AA8-4A49-9FA6-001B690C0F05_zps1xqk2nrd.jpg


Using Volvo firewall grommet with multiple pass throughs

57573CEC-1DA9-4BCF-9A6F-8CD486C5F06D_zpspqitzsnf.jpg


Distributor is at the machine shop for customization.
 
Didn't drive it today. Wanted to get the valve clearances check & adjusted before anything else, since I know they are not to the spec (.014" Int/Exh) Matt gave me for the cam I purchased some years ago.

This is what I measured today cold:

#4 Exh Int. #3 Int. Exh. #2 Exh. Int. #1 Int. Exh.

.024" .012" .018" .034" >.008" .018" .018" .012"

Not good. Pretty sure I must have mixed the buckets for #3/#2 EXH, no way he could have got those setup so far out. I've put about 300 miles on the motor, hopefully no damage done to valve train.

I tried several 'hook' tools from my local machine shop, nothing close

X19_0404.jpg


So, I need to make one ASAP :sad:
 
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I have a tool

Hussein, I have a Brian Pimm Special tool. I won't need it for a little while yet so I can send it to you.

Cheers,

Rob
 
rjplenter said:
Hussein, I have a Brian Pimm Special tool. I won't need it for a little while yet so I can send it to you.
Cheers, Rob
Click to expand...

Thanks again for the offer, Rob.

I was able to adjust them with the tool we made.

Now they are all .014", except exh #1, which is a loose .015"; couldn't find a shim to bring it down that extra thou or so. In any event, the motor sounds much better :)

Took it for a spin; still lean under (gently increased) load.

Raised the base fuel pressure so that the AFR's are in the 14.7-15.2 range with the O2 disconnected. Now around 48psi under vacuum. Previously the AFR's would rise over 16 with the engine hot & O2 disconnected.

Still waiting for the hybrid distributor, so next I'll close up the plug gap a touch, and maybe retard the base timing another couple degrees for the time being.
 
Picked up the dist. today - shaft was turned to 8mm post in upper section & 8mm passage in lower section, then chamfered & braised together.

X19_0350.jpg


X19_0349b.jpg


unfortunately the upper bushing moved (outwards) when the housing was welded - so when he did the shaft mod, the overall length was off. Have to have him take the shaft apart again & shorten it about 1/2"
 
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X19_0349.jpg


All the pieces for the distributor. Shaft is 156mm for the length housing we made. Lubed and assembled now. Worked on the wiring from LH - EZK when we got home from the Rally for Climate Change Awareness in NYC today.
 
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Car is running on the Volvo EZK117 system. I tried both NA & Turbo ECU's to see if there was much difference in performance. The particular reason for using the turbo version was that it has timing advance at idle for AC & Cooling fan onset. That didn't work out, as it held the advance long enough on throttle tip in to generate knock.

I regapped the plugs to .028", and set the base timing to 10ºBTDC

The plugs didn't look bad

Still had knock under load, so I backed base timing back off in 1-2 degree increments until I couldn't hear any knock under load, which happened around 3-4ºBTDC. Engine idles well *750-800rpm, MAF output voltage set at 1.9v.

The problem with running that little base timing is that it negatively impacts coolant temp at idle. Temp drops just below 'normal' when moving. If overall drivability seems OK, I'll look for a smaller OD WP pulley to increase WP speed at idle rpms.
 
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