MFI Tuning

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g3ngs2
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MFI Tuning

Post by g3ngs2 »

Wondering who currently is the good to go to for MFI tuning (by good I mean does it right and doesn't charge the earth)

I had a recommendation of a local shop who I went with based on time -
Problem as I see it at the moment is that:

- Throttle isn't getting to full (at the engine end) more like 60-70%
- The dual lambdas (@hot66 post Le Mans I had an Innovate DLG-1 dual wideband kit shipped over from the US) in the heat exchangers are telling that on both banks there's an AFR of 22.4

It might be that the whole lambda set up is on the p155 - but then I also have an invoice from the shop for 9 hours labour and 30L of fuel which says they read and recorded the arrival AFR (no sign of those recordings) that it was tuned to base level and test driven - so something somewhere isn't right..........
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matteo68
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Re: MFI Tuning

Post by matteo68 »

I’d recommend Fred Pentecost at Tower Diesels - https://www.towerbridgediesels.co.uk/ - (used by Tuthills, Redtek, Greatworth amongst others). Party because these guys swear by him and partly because he was honest enough to say he couldn’t do a full-house conversion of my 001 pump to RV1668 2.5 ST spec with the correct V94 space cam and V1058 regulator. Without hesitation he referred me to Eisenbrandt in Germany who had the necessary facilities to do the work. I was really impressed that he was prepared to turn away work rather than feed me a load of BS and ultimately deliver a compromise solution and that’s worth a lot in my book.
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AndrewSlater
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Re: MFI Tuning

Post by AndrewSlater »

Firstly I know nothing about MFI but I do own an Innovate AFR kit.

Your AFR setup sounds wrong to me.

If I recall my Innovate only reads up to 22.4 in air alone, and you only see this when you calibrate your sensor.
Have the sensors been calibrated correctly?

There is a video here demonstrating an innovate setup showing 22.4 in air
https://www.youtube.com/watch?v=YDavXMTJa3k

Comments in the thread suggest a reading of 22.4 on a car is a bad sensor.

Good luck
Andrew
1966 Porsche 912 Slate Grey, red interior - first owner owned for 41 years
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210bhp
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Re: MFI Tuning

Post by 210bhp »

Unfortunately, as is often the case, it’s a mistake to consider MFI tuning starting with the pump. In fact, it’s the last thing you touch.
I suggest you get a copy of two booklets, ‘check, measure, adjust’ and Michael Burgess ‘MFI’ and you will soon get a plan of attack, some of which you can do yourself relatively easily. Bosch MFI pumps are a very sound piece of engineering and if you start changing settings here first you soon get ‘lost’ from the starting point. Only if all else fails would I suspect a faulty Bosch MFI pump (unless someone has been tampering with it already).

Regards
Mike
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g3ngs2
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Re: MFI Tuning

Post by g3ngs2 »


Thanks James, I'll give them a call l. The non BS approach would be welcomed.

Andrew thanks, I'll take a look at that now and then head back into the garage to have a fiddle with it.

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matteo68
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Re: MFI Tuning

Post by matteo68 »

g3ngs2 wrote:Thanks James, I'll give them a call l. The non BS approach would be welcomed.

Andrew thanks, I'll take a look at that now and then head back into the garage to have a fiddle with it.

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Re: MFI Tuning

Post by matteo68 »

210bhp wrote:Unfortunately, as is often the case, it’s a mistake to consider MFI tuning starting with the pump. In fact, it’s the last thing you touch.
I suggest you get a copy of two booklets, ‘check, measure, adjust’ and Michael Burgess ‘MFI’ and you will soon get a plan of attack, some of which you can do yourself relatively easily. Bosch MFI pumps are a very sound piece of engineering and if you start changing settings here first you soon get ‘lost’ from the starting point. Only if all else fails would I suspect a faulty Bosch MFI pump (unless someone has been tampering with it already).

Regards
Mike
https://www.pbase.com/slidevalve911rsr/ ... _bosch_mfi
'72 T 210 2176 (ex-Hawaii donor car for '72 M491 2.5 SR)
'72 S 230 0347 (two-owner tangerine unicorn)
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Re: MFI Tuning

Post by BILLY BEAN »

Tuning MFI implies the complete system ( MFI pump, throttle bodies, linkages etc) is installed on the engine and in the car. Fred Pentecost will restore mechanically and cosmetically an MFI pump and set up the flow and distribution on the Bosch machine designed for MFI pumps to the original pump specification. However, this requires the pump to be removed from the car and it sounds like you want tuning whilst the pump is installed and Fred does not "tune" MFI in that sense.
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g3ngs2
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Re: MFI Tuning

Post by g3ngs2 »

Sorry about that Matt, I suppose there's a clue in your user name

Just went and recalibrated the DLG. I'll have to take it out on a run later on and see what's what when it gets up to temperature.

Early indications are it's very lean which might indicate that the square root of f-all has been done...

I also note that my fire extinguisher that I picked up LMC (only because it's the same colours as the car) that was still in the packaging which was taken along for the ride, as it was it's second drive (and longest at 15 mins) when the car was dropped off their seems to have disappeared...

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MFI Tuning

Post by hot66 »

210bhp wrote: Wed Aug 03, 2022 10:12 pm Unfortunately, as is often the case, it’s a mistake to consider MFI tuning starting with the pump. In fact, it’s the last thing you touch.
I suggest you get a copy of two booklets, ‘check, measure, adjust’ and Michael Burgess ‘MFI’ and you will soon get a plan of attack, some of which you can do yourself relatively easily. Bosch MFI pumps are a very sound piece of engineering and if you start changing settings here first you soon get ‘lost’ from the starting point. Only if all else fails would I suspect a faulty Bosch MFI pump (unless someone has been tampering with it already).

Regards
Mike
this is all from memory and I admit I know enough to be dangerous, but not enough to be an expert :lol: ... check with CMA before messing with anything. ALSO ... IMPORTANT, every change you make, make a note somewhere so you can go back to the original settings if it all goes tits up.

Mike is correct .. basically you need to make sure engine is right ( eg valve clearnances etc ) , then the timing is correct . From there in basic terms, with all rods disconnected its making sure the throttle bodies are all flowing air equally and their butterflies are sitting correct. Easier to do this with the throttle boies on a flow bench, but CMA describes how they should done on the car . Cant remeber exactly but also the air bypass screws should start at about 2 turns from their bottom ( double check to see what CMA says ) . Then fit and adjust the rods between all the buterflies and set so non of the butterflies move from their position when the rods are fitted. From here go back and make sure the rod from pump to the main linkage bar is set to the critical lenght as specified in the CMA manual. At this point youve only got the two rods from the main linkage bar to each throttle bank.these can now be adjusted and fitted so again when fitted the throttle butterflies do not move .. hopefully both these rods on either side should be similar lenght .. if not, then on the left side of the main throttle bar the end piece can be adjusted slighlty.

Then connect the throttle rod to the main linkage ... again hopefully it wont pull open the butterflies etc . If it does you can adjust the length at varoius points incl by the gearbox

That should be a good starting point. Start the engine and get it warmed up. Once hot using a synchrometer measure the air flow through each throttle body and following CMA , adjust the airbypass screws 1/2 turn at a time to get them all flowing equally. and a steady idle

Then go for a drive and monitor your AFR's especially at full load , top of rev range. IF your AFR meter is correct , then you can see wether the main rack needs leaning out or enriching. ( you can buy special tools for this )

Always adjust the main rack as it effects fueling through the entire rev range. Adjust until you get the AFR's to say 12.5 - 13:1 at full load high revs. Keep it on the rich side. At this point you will need to adjsut the air bypass screws again to settle the idle .

Then move on to the idle rack if need to fine tune idle afr and again adjust the air bypass screws on the throttle bodies once youve happy.

After this you can play around with fine tuning


ON the AFR meter, the lambdas need to be set in free air , have a read of the instructions
James

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hot66
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Re: MFI Tuning

Post by hot66 »

these are the MFI tools , although they are fairly basic for what you spend.. easilly could be made

https://www.fvd.net/de-en/FVD721T86/fue ... e-set.html
James

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Its not how fast you go, but how you go fast ;)
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Re: MFI Tuning

Post by hot66 »

maybe your guys have done the above, but not adjusted the MFI pump ? ~Still, follow the above and check wether what they have done seems to follow it . The important thing to check is the rod length between the pump and the linkage
James

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Re: MFI Tuning

Post by 911hillclimber »

I'm amazed Tower are still going, did my pump and injectors back in 1999..

However, you are looking for an outfit who can dial it all in i think, bob Watson did mine on the Osselli dyno back then, and then it was hard to list those who could actually do this task.

today?
Got to be Tuthil, Autofarm and any of the older specialists?
Neil Bainbridge come to mind too, but i would also ask Mike Champion at MCE.

It took Bob some time to dial my 2.4 in and he really knew what he was doing.
The fine drillings in the butterfly manifolds can readily corrode 'shut'; everything has to be as new.
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g3ngs2
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Re: MFI Tuning

Post by g3ngs2 »

Well I'm up for a ring around to have it seen too properly. Once it's done done I'm happy to maintain it but right this learning curve would be straight to hell in a hand cart.

This morning I measured the rod and it looks to.be 114mm

This evening aI recalibrated the Innovate DLG and got it up to temperature

At idle right lambda 7.4 AFR and the left 13.4 AFR
At part load right right 12.1 and the left 15.4
Full load not really an option as it appears the cable is not getting the full travel on the engine side (suspect that happened when the engine went back in)

Alternator isn't charging.. but is a new alternator, multimeter says there's juice either side of the fuses in the engine bay. But suspect whilst it was at the "tuners" and the new starter motor crapped out they may have not have wired the starter I sent up to them properly.

I do though have a bill from them with 4 digits that's says base tune and

Which was round about the time I realised that I don't have anything suitable to lift the car and take a look as last time around that I had one of these was about 2010 when my garage was at the end of incline steep enough you could hang the back out of the garage and 90% of what you wanted to do but not so steep that you ran aground

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Re: MFI Tuning

Post by g3ngs2 »

On a lighter note these arrived from the fine folks at isaydingdong

The shell static cling is an off the shelf. The Sonauto one at the back was a custom order. Static cling because zero hope of getting it bang on the first time... though in the first go it went on perfectly... then realised that the window wasn't quite clean enough but that gave it a sort of aged look that the phone camera hasn't really picked out very well, but as I like it, it can stay as is

ImageImage

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