How much fuel pressure?

[Claymore]

21 hours ago, RobSR said:

You’re saying it’s ‘impressive’ that I don’t need to know the exact FPR the guy is running - that’s because whatever FPR you run, the pressure changes based on the engine vacuum not the FPR - if someone fits an eBay / faulty / shit FPR that doesn’t alter the fuel pressure correctly based on the engine vacuum and boost - that’s not my problem. 

This 👆. A working / good quality 1:1 ratio fpr will increase or decrease fuel pressure the same amount as the MAP changes. That's the whole point of a reg.

On 1/31/2022 at 3:05 PM, Sam44 said:

So I'm very confident it will also help benafit the 4efe lads on a adjustable fpr. 

Thew for these lads you have to run the pink 4age/7afe/5efhe 230cc injectors running around 2.5 to 2.7 bar fuel pressure setting it up with the vacume line on. Some more kick ass power. Use the eBay aero motive copy fpr these only add around .2bar of fuel pressure on throttle great for the 4efe and bigger injectors not to go to high, just for good fueling. On the short turn fuel trim, the long term closed loop trim will more are less be the same at operating temp as on the factory 198cc green units.

For the turbo lads the fse is the one to get. 

The 230cc pink denso injectors are only 2 steps up on the denso injector size so you can reduce the fuel pressure to hit the sweet spot. These injectors are found on every Toyota of this era at and above 100hp to around 140hp, abit like jetiing a carb.

This sounds a lot like back tracking after what was said on Callum's build thread where you proposed adding larger injectors and lowering the fuel pressure? 

Now you want larger injectors (more fuel), higher base fuel pressure than stock (more fuel again) and a reg that doesn't increase fuel pressure much to reduce fuel at WOT because otherwise it runs pig rich due to being open loop? This sounds more like a bodge every minute and what if you get a fake fpr that actually works at the correct ratio of 1:1? Pig rich WOT.

All I'll add is, if your planning on adjusting fuelling my advice is to install a wideband O2 sensor first or get it checked on a dyno. The Det 3 + piggy back ECU is so cheap it doesn't make sense to bodge stuff anymore. Especially when you consider that it also adjusts timing, datalogs and with the addition of a mac solenoid it can adjust boost levels via a PWM table. £250 new for a piggyback, datalogger and EBC all rolled into one.

[Sam44]

No claymore my standard fuel pressure rating is 3bar vacume line on so 2.5 to 2.7bar is lower. There the figures guys I'm giving and people are free to try them as I have. Have you or again is this guess work. 

Buy the way the fpr is  mechanical the ECU is electrical the speeds they work are worlds apart. 

I'm running the pink injectors on my paseo build at 2.7bar and the difference in power on stock green units is night and day big gain alot more torque. The plugs are nice and brown. And it passed mot emmisions. It does run slightly rich on cold start the. 

People give it a go. 

I believe Callum is going to do it, we can wait on his feed back. 

By all means put an ECU on it as well these mods will help the ECU. 

 

 

Edited February 1, 2022 by Sam44

[Claymore]

12 hours ago, Sam44 said:

No claymore my standard fuel pressure rating is 3bar vacume line on so 2.5 to 2.7bar is lower. There the figures guys I'm giving and people are free to try them as I have. Have you or again is this guess work. 

Buy the way the fpr is  mechanical the ECU is electrical the speeds they work are worlds apart. 

I'm running the pink injectors on my paseo build at 2.7bar and the difference in power on stock green units is night and day big gain alot more torque. The plugs are nice and brown. And it passed mot emmisions. It does run slightly rich on cold start the. 

People give it a go. 

I believe Callum is going to do it, we can wait on his feed back. 

By all means put an ECU on it as well these mods will help the ECU. 

The workshop manual figures I quoted state the fuel pressure should be 2.8 bar base and anywhere between 2.27 and 2.55bar (average 2.4 bar) with map reference attached. Any how, recommending that other people use 2.5-2.7 bar referenced is at the richer end / over stock pressure not lower than is specified in the workshop manual. It is obviously lower than your readings of your car with your gauge.

If yours is running 3bar with reference, that is already well over stock figures (max 2.55bar), maybe your car has a fault. Or maybe the fp gauge your using reads over?

All I am saying is this method of "tuning" is best described as crude and no one can argue that more accurate fuelling control wouldn't be achieved with a piggy back and WBO2 combo.

It's all about how much compromise someone is willing to accept. There's a lot of options when it comes to tuning and I wouldn't take certain routes. Other people are free to try whatever they want and please report back with dyno figures including an AFR and MAP trace.

[Sam44]

Is the workshop mannula a Toyota manual?. 

Like everything else I've measured other 4efe/fte & 5efe units. (Just like the unknown cam and thermostat) Which I think I've already mentioned. Another area which was hard to get accepted, but I'm hoping is out there now for people to use. Yes it was me that altered the information on the Toyota 4e engine on wikki to reflecte the real difference in cam and valve springs. 

If you have the money for a ECU either piggy back or standalone then of course this could benafit you more in other areas as well as power (fuel economy), But tuning is tunning, every system on the production line starlet can be optimised/upgraded. Every system.

As I have research these vehicles from web sites all over the world. it has become apparent there are many gray areas still, with alot of conflicting information/data. The best way around this is to test and trust the figures Infront of you (which I've done and continue to do). 

It's also apparent the age group and pocket size these little cars attract. With on average I'd estimate a 2 in 10 car being built/tuned running a piggy back controller and 1 in 20 running a stand-alone, so the advise I give can now be put to use by this audience, I also believe they like to learn and try to understand, but love to see there own work pay off with feelable power gains. Ive got a feeling you already know this and are just joining in on this because that's ho you are, which I accept. Abit like talking to a child, and that's not a dig just how I feel when replying to you comments. 

It might benefit your self to read into/understand the porpose of the fuel pressure regulator. 

It's there to maintain a constant fuel delivery rate, (when there is a vacume acting on one side of the injector, sucking the fuel out, it reduces fuel rail pressure, as the vacume becomes a positive pressure acting on the injector the fpr increases rail pressure trying to maintain a constant delivery rate in a constantly changing environment. Unfortunately it's a basic mechanical devices that is fast to respond in different areas. Giving a timed offset with the ECU. 

I do however think it's quite hard to beat a manufacturers map. This map has been developed over years (around 3 on this vehicle) in multiple environments at different altitude (real world) over 100,000s of covered miles. It's very safe and can easily deal with fpr adjustment even small injector increment changes. Sometimes helping/improving a basic system/systems/age & period related). This was from a era were trend data could not be uploaded from the vehicle in service and software updates readily available (the era we now live in). I would also like to add that a piggy back controller uses the factory map but tricks it. This is quite hazerdes to do because you are now alone flying by the seat of your pants factory fail safes and diagnostic data (flash codes) no long apply. 

The point here is to do your research on people to map the car and if you are going to do it yours be warned. We have seen recently the confusion and mess easily created by fast mapping. I will say that from my research Rob ho has commented on the topic and racetec are the some of the most recommended experienced people to do this with maps I'd guess at being developed over many years. 

As for the det 3 controller it's EPROM reference tables are low resolution it's frustrating to work with. 

Alittle more money spent will get you a much better ECU. Like everything else. 

I hope all the information and tunning tips I give go to good use and help people/members get what they are looking for by joining the site. 

Im now ready for a quite predictable reply. Hoping it involves the answer to my question. 

Edited February 2, 2022 by Sam44

[Claymore]

4 hours ago, Sam44 said:

Is the workshop mannula a Toyota manual?. 

Like everything else I've measured other 4efe/fte & 5efe units. (Just like the unknown cam and thermostat) Which I think I've already mentioned. Another area which was hard to get accepted, but I'm hoping is out there now for people to use. 

If you have the money for a ECU either piggy back or standalone then of course this could benafit you more in other areas as well as power (fuel economy), But tuning is tunning, every system on the production line starlet can be optimised/upgraded. Every system.

As I have research these vehicles from web sites all over the world. it has become apparent there are many gray areas still, with alot of conflicting information/data. The best way around this is to test and trust the figures Infront of you (which I've done and continue to do). 

It's also apparent the age group and pocket size these little cars attract. With on average I'd estimate a 2 in 10 car being built/tuned running a piggy back controller and 1 in 20 running a stand-alone, so the advise I give can now be put to use by this audience, I also believe they like to learn and try to understand, but love to see there own work pay off with feelable power gains. Ive got a feeling you already know this and are just joining in on this because that's ho you are, which I accept. Abit like talking to a child, and that's not a dig just how I feel when replying to you comments. 

It might benefit your self to read into/understand the porpose of the fuel pressure regulator. 

It's there to maintain a constant fuel delivery rate, (when there is a vacume acting on one side of the injector, sucking the fuel out, it reduces fuel rail pressure, as the vacume becomes a positive pressure acting on the injector the fpr increases rail pressure trying to maintain a constant delivery rate in a constantly changing environment. 

I do however think it's quite hard to beat a manufacturers map. This map has been developed over years (around 3 on this vehicle) in multiple environments at different altitude (real world) over 100,000 of covered miles. It's very safe and can easily deal with fpr adjustment even small injector increment changes. The point here is to do your research on people to map the car and if you are going to do it yours be warned. We have seen recently the confusion and mess easily created by fast mapping. I will say that from my research Rob ho has commented on the topic and racetec are the some of the most recommended experienced people to do this with maps I'd guess at being developed over many years. 

As for the det 3 controller it's EPROM reference tables are low resolution it's frustrating to work with. 

Alittle more money spent will get you a much better ECU. Like everything else. 

I hope all the information and tunning tips I give go to good use and help people/members get what they are looking for by joining the site. 

Im now ready for a quite predictable reply. Hoping it involves the answer to my question. 

It's only fair that I get to respond. 

The manual(s) I quoted from are both Haynes manuals as stated on the previous page. I did ask someone to check the official Toyota manuals with Jay. I'm happy to use the figures I quoted, I've always found the Haynes manuals to be reliable.

I do know how a fpr reg works (we have already discussed it on the threads where you suggest using a reg set at a fixed 4 bar (un referenced) for turbo applications. 😵). I also seem to remember having to explain to you how / why a 1 bar map sensor does or doesn't work on N/A+T builds on another thread you started so I know the feeling of educating children also. No offence to you either.

I don't take any pleasure in having these types of discussion, it's not who I am at all.

The DET3 piggy's use 16x16 tables, same as the emanage blue from the info I can find. 

I think the rest has already been covered in previous replies by different people as well.

Edited February 2, 2022 by Claymore
Clarity

[Sam44]

Thanks for the information as always.

if others can test there standard fuel pressures it would be a big help.