Benefits of a BPU Supra with SAFC

Just reading a similar thread on SF and it got me thinking. Im BPU at the moment and got a bit of an itch to spend some money on it. Not too much so this might be a good option.

Has anyone first hand experience of adding an A/F signal fudger to their BPU Supra with good/bad results? Or indeed have you got any thoughts on the matter. Finally, would this requite dyno tuning (I imagine so).

(Just had a thought - 02 wideband would be a smart option to go with).

there is no point having a SAFC with 440s injectors on stock tubbies, nothing to trim.

something to alter the ignition timing might be useful with stock turbos and injectors (emanage), with the addition of FMIC, walbro etc.

(Just had a thought - 02 wideband would be a smart option to go with).

Well if you get one of these, that will tell you if the fuel system is ok or needs uprating / tweaking. That's what I'm doing first anyway.

something to alter the ignition timing might be useful with stock turbos and injectors (emanage), with the addition of FMIC, walbro etc.

You don't say if you've got JSpec or UKSpec.

On a UKSpec it's a nice-to-have, I've got 30% trimmed off at one point, despite running the 550cc injectors flat out at max power revs.

The SAFC also alters ignition advance indirectly. Typically where you take off fuel ignition is slightly advanced and vice versa. (this refers to the base maps after an ECU reset. The final maps will be trimmed according to knock 'noise')

Im jspec, 440's, walbro, stock smic, decat, plugs, restrictor ring, fcd. No EBC or AF control.

From what I read on SF, it seemed a good purchase to get just a little bit more. I'd love to spend something on the Supe just now and feel a bit of a difference (im under no illusions). I think FMIC or 02 WB might be cool.

yeah remember on the supraforums the US guys are running 550s not 440s, and like John said on 550s a SAFC would be usefull.

Im jspec, 440's, walbro, stock smic, decat, plugs, restrictor ring, fcd. No EBC or AF control.

if your thinking of upgrading in the future to hybrids or a single the SAFC would be a good purchase but other stuff would be higher on the shopping list, if your leaving it stock i ran mine for 2 years like that at 1.2 bar with no addition control and it was fecking awesome however i did have a front mount I/C, if i were you spend your money on that rather than the SAFC

Useful to have but results depend on who sets it up - mine ended up giving me a bit more BHP, more lag, higher fuel consumption and a shopping list for a FPR and bigger injectors - odd really because most people trim a fair bit out.... thoughts based on the graph below?

http://www.megaboost.co.uk/supra/mine/dyno/thor-dyno2-01.jpg

Thanks folks. Looks like its probably a FMIC...or alloys

...thoughts based on the graph below?

 

http://www.megaboost.co.uk/supra/mine/dyno/thor-dyno2-01.jpg

It doesn't look too bad, until 5500rpm it hovers around 12.5 then dips into the 11s

This is usually perceived as 'safe' mapping but not excessively so.

Have you ever cleaned your injectors, or suspected the fuel pump of being 'lazy'? If that graph shows your stock ECU behaviour then it's different to mine (or others I've seen)

Mine on it's own would dip into the 10s as soon as the second turbo kicked in. Similar to US-Spec, OBDII.

I had to play a bit with the AFCII to make it stop wasting power using excess fuel as a coolant.

I had to play a bit with the AFCII to make it stop wasting power using excess fuel as a coolant.

Do you want to play with mine too??

Thanks for your input - I've had a new fuel pump ready to fit for a while now, not because the old one is broken but purely because it's something I haven't changed and the one in there could be the original.

Injectors are untouched so could probably do with a clean or at least a decent check - the only attention they have had to date is from fuel additives. It's something I'd been putting off until I decided on the next stage really, I was thinking of single with bigger injectors at some point but I'm still undecided on that.

I guess I just want it to be slightly less safe

That's stock ECU with an AVR and SAFC II bolted on, the only major change since then is the replacement of a split hose to the EGBV actuator.

It doesn't look too bad, until 5500rpm it hovers around 12.5 then dips into the 11s

This is usually perceived as 'safe' mapping but not excessively so.

 

Have you ever cleaned your injectors, or suspected the fuel pump of being 'lazy'? If that graph shows your stock ECU behaviour then it's different to mine (or others I've seen)

Mine on it's own would dip into the 10s as soon as the second turbo kicked in. Similar to US-Spec, OBDII.

 

I had to play a bit with the AFCII to make it stop wasting power using excess fuel as a coolant.

Do you want to play with mine too??

It's a piece of piss -- all you need is a wideband, a friend to write down the readings at fixed intervals and the balls to drive full-boost in high gears for some time.

The gotcha is that speeds get silly very quickly and you have to keep your foot planted until redline.

MUCH easier and safer on RR, but the readings could be out by quite a bit.

It's a piece of piss -- all you need is a wideband, a friend to write down the readings at fixed intervals and the balls to drive full-boost in high gears for some time.

The gotcha is that speeds get silly very quickly and you have to keep your foot planted until redline.

 

MUCH easier and safer on RR, but the readings could be out by quite a bit.

Aah haven't got a wideband and dont know I'm doing Trip to RR required..............

Yep, without a WB don't even *think* of DIYing fuelling.

 

MUCH easier and safer on RR, but the readings could be out by quite a bit.

this is a very good point John is making i didnt even set my boost controller up properly cos i knew the car was being set up by profesionals, i felt a complete twat just blasting up and down the local by-pass and you get the temptation to overtake everything cos your on a "good" run pissing everyone off you overtake getting flashed and 2 fingers all the way

The RR is good for getting the bulk of settings right, but it's on the road that you really get full load, so you might see more boost than you've bargained for (at the same revs).

Sometimes you see *less* boost on the road, if the RR operator was artifically keeping the engine in static load. This creates a very 'meaty' torque curve on paper, but driving the car feels otherwise

All these mean that AFRs could be off by a whole point sometimes.

It also depends on winter/summer, that's why it's nice to have the wideband.

The alternative is to have it mapped filthy rich 'just to be safe'

Apart from wasteful it also leads to unnecessary carbon deposits and it costs power. Running richer than 11:1 is a pathetic attempt to perform in-cylinder cooling using extra fuel (which isn't particularly good at it)

Water is *so* much better