Would like to get 400bhp from my ZED it's a UK manual

Been on 300.org went to upgrades and looked at stage charts from stillen and SGP, (this bring's up NEW ZEALAND 300zxOC) it show's 405BHP at 14.5psi is this poss on a UK car? What can i get for £500-£1000?

Any help would be good, phone number's Web site's etc.

Ive been looking at obtaining 380 - 400bhp myself!

 

It appears that turbos and injectors are good for a maximum of 400bhp. Any more than that you will need new 555 injectors, uprated intercoolers, uprated turbos, new oilcooler and an uprated fuel pump. All this will probably set you back about £5k.

 

However, with a good ECU, im looking at Apexi Power FC, a boost controller running at 1 bar, and a good breathing induction kit such as Apexi and a decatted sports exhaust you should be able to obtain 380 bhp!

 

With an Apexi Power FC, boost controller and Apexi induction kit, all this would cost about £2k as the Apexi Power FC is about £1600 fitted. It all depends on where you plan to go with you car. If you know you will end up with 600 bhp in the next 2 years then Apexi Power FC or alike it must be.

 

However, if you want a max 400bhp then look at JWT that has a map on it already. This is about £100. So the cheap route of obtaining 380 bhp would set you back about £1k if you pay someone to fit boost controller and ECU. Or about £500 all in if you do it yourself!

 

However, I plan to leave my cats in as if those turbo seals go, thats £1500 repair job!

 

HTH

Cats wont let you get above 320 IMHO, they stangle the car too much. the t25 exhaust housing is small enough as it is, so its ass being blocked aint gonna help matters :-)

Ive been looking at obtaining 380 - 400bhp myself!

 

It appears that turbos and injectors are good for a maximum of 400bhp. Any more than that you will need new 555 injectors, uprated intercoolers, uprated turbos, new oilcooler and an uprated fuel pump. All this will probably set you back about £5k.

 

However, with a good ECU, im looking at Apexi Power FC, a boost controller running at 1 bar, and a good breathing induction kit such as Apexi and a decatted sports exhaust you should be able to obtain 380 bhp!

 

With an Apexi Power FC, boost controller and Apexi induction kit, all this would cost about £2k as the Apexi Power FC is about £1600 fitted. It all depends on where you plan to go with you car. If you know you will end up with 600 bhp in the next 2 years then Apexi Power FC or alike it must be.

 

However, if you want a max 400bhp then look at JWT that has a map on it already. This is about £100. So the cheap route of obtaining 380 bhp would set you back about £1k if you pay someone to fit boost controller and ECU. Or about £500 all in if you do it yourself!

 

However, I plan to leave my cats in as if those turbo seals go, thats £1500 repair job!

 

HTH

 

Forget the power FC as its max is about 400 bhp anyway. A good Chip, (John Dixon, Andy Z or DTA) = £100 to £300, + boost controler ie Apexi/Greddy/HKS=£300 to £500 and a good induction kit = £150 to £300 will deliver the power your looking for. Min = £550 max = £1100.

 

Forget the Decats unless you have garenteed evidence that your car really is less than 60K miles. Unfortunately far too many Zeds that have come into the country over the last 3 years claim to be 60K cars but clearly are not.

 

Ask yourself this. If cars at 30K milage are to cost prohibertive to keep in japan then where the fook have all these 1989 to 1992 cars been. The truth is they've been getting thrashed round Malasia for years. Because there are no records they are bought by unscrupalous traders who clock em to 60K and sell em as Jspec. So unless you have documentation to prove that its milage is genuine you should assume it not what it says.

380bhp with cats left in??? show me a dyno chart for that one :-)

380bhp with cats left in??? show me a dyno chart for that one :-)

 

You won't see that at the wheels without 555's but at the Fly then its easy peesy as per parts and upgrade I've stated. There are dyno's on TTnet and quite a few here. ie JD had 370 at the wheels with this kind of set up and even only a 18 percent power loss through transmition its well over 400 bhp at the fly.

 

If you don't believe me then show me why you think different. I'm trying to help the guy make serious power gains without blowing his turbos or making his engine unrelyable. Anybody can be negertive. I also have had and run my Z for 7 years in various modified states and think I'm more than qualified through experience to be able to make justifiable claims from experience.

 

Infact top tuners such as JWT, AMZ, JE, and Mines have made these claims for years without being sued for false representation. Who the fook are you?

Im talking at the wheels Mark, most of the mericin's run hi-flo sports cats, at over 380 your pushing stanard turbos into there ineffciency range, the stock exhaust housing as ive said are very restrictive, hence the divorced housing/decat allow quick spool due to less back pressure on the exducer. With the cats left in there is a lot of back pressure which wont allow the turbo's to spool effeciently enough to the levels required to get above those sort of numbers at the wheels. Of course anythings possible but doing it right usually saves problems in the long run.

 

Its the basics of tuning, no good getting plenty in one end, if you cat get it quickly out through the other.

 

Oh and im marty pleased to meet you.

Im talking at the wheels Mark, most of the mericin's run hi-flo sports cats, at over 380 your pushing stanard turbos into there ineffciency range, the stock exhaust housing as ive said are very restrictive, hence the divorced housing/decat allow quick spool due to less back pressure on the exducer. With the cats left in there is a lot of back pressure which wont allow the turbo's to spool effeciently enough to the levels required to get above those sort of numbers at the wheels. Of course anythings possible but doing it right usually saves problems in the long run.

 

Its the basics of tuning, no good getting plenty in one end, if you cat get it quickly out through the other.

 

Oh and im marty pleased to meet you.

 

 

He don't say RWHP anywhere. He appears to me to be Talking as though he's looking for a 120 bhp kick in the pants which is a big dollop and dramaticly alters the power to weight ratio and most importantly ups the PPF torque figures. Which has more bearing on prepulsion that telephone BHP figures.

 

You are only now saying RWHP. Car makers only ever talk Flywheel. Lets face it the Ferrari Enzo is only 600BHP at the fly so most people talk fly figures.

 

Real performance coms from power to weight and nice wide torque/ power band. £800 to get a 2 fiths more power or increase you power to weight ratio by 60% is good value and not to be sniffed at.

 

To increase power to 400RWHP your talking almost doubling the power out put which Shouldn't even be dreamt of without serious upgrades. I should know I've read the book, eaten the pie and passed the KY to my bank manager.

ahhh sorry Mark, i always talk wheels not fly, a lot of people dont distinguish between at fly or wheels and often dont realise there is a difference, and as you know its quite a big one, they usually read figures and just say "hell, i want that"

I take my firgues at the wheel, i always have and always will no metter what type of car it is.

Also, people dont realise that theres a lot more involved in getting the power they require, depends on lots fo things as you know such as compression, turbo condition, fueling, so those figures are just guestimates at the end of the day. Then you have all the other factors involved such as brakes, clutch cooling, and longitivity of turbos and engine components. Something people dont seem to take into consideration when wanting more power :-(

Forget the power FC as its max is about 400 bhp anyway. A good Chip, (John Dixon, Andy Z or DTA) = £100 to £300, + boost controler ie Apexi/Greddy/HKS=£300 to £500 and a good induction kit = £150 to £300 will deliver the power your looking for. Min = £550 max = £1100.

 

Forget the Decats unless you have garenteed evidence that your car really is less than 60K miles. Unfortunately far too many Zeds that have come into the country over the last 3 years claim to be 60K cars but clearly are not.

 

Ask yourself this. If cars at 30K milage are to cost prohibertive to keep in japan then where the fook have all these 1989 to 1992 cars been. The truth is they've been getting thrashed round Malasia for years. Because there are no records they are bought by unscrupalous traders who clock em to 60K and sell em as Jspec. So unless you have documentation to prove that its milage is genuine you should assume it not what it says.

 

HI Mark, Thats good advice. Many thanks.

 

With these plugin ECUs though, I thought most are mapped to cater for cars that are decatted. Can you recommend a chip that will cater for a car that has the cats still in place and would cater for a boost controller and induction kit? Also, would would you recommend to do it?

 

Many thanks

HI Mark, Thats good advice. Many thanks.

 

With these plugin ECUs though, I thought most are mapped to cater for cars that are decatted. Can you recommend a chip that will cater for a car that has the cats still in place and would cater for a boost controller and induction kit? Also, would would you recommend to do it?

 

Many thanks

 

You need to speek to the person who is going to supply the chip. Tell them what you wish to acheive and be honest about your car. They will provide you with a mapped chip for as near as dam what you car has, but be prepared for the fact that any weak link in your engine will be highlighted and most likely fail if the car is not in good health.

 

Also chips such as JWT, SE, Mines (or the cheepest root being a 300zx.co.uk member would be to talk to John Dixon, Chris Get Greddy or Danny at DTA) are not exact set up for your car and though they will give good perfomance upgrades with appropriate boost will always be within the margin of safety. Real power gains can then be acheived using an emilator to tweek your chip durring a rolling road sesson. That i'm affraid isn't cheep.

 

You can keep the cats and get more power, but v6power is right decating will liberate about 30 t0 40 bhp extra when mapped with better indution and higher boost, but tired Turbo seals will give up the ghost.

ahhh sorry Mark, i always talk wheels not fly, a lot of people dont distinguish between at fly or wheels and often dont realise there is a difference, and as you know its quite a big one, they usually read figures and just say "hell, i want that"

I take my firgues at the wheel, i always have and always will no metter what type of car it is.

Also, people dont realise that theres a lot more involved in getting the power they require, depends on lots fo things as you know such as compression, turbo condition, fueling, so those figures are just guestimates at the end of the day. Then you have all the other factors involved such as brakes, clutch cooling, and longitivity of turbos and engine components. Something people dont seem to take into consideration when wanting more power :-(

 

Hi Marty

 

Sorry if I get prickley at times. Just too many people on hear want to poo poo lads who are trying to improve the performance of their cars on a limited budget. Most people until they get involved with the serious tuning bug speek Fly. They talk about the new 2.5 Scooby being 320 bhp when infact power to the wheels in about 240bhp which still swishes it along, but 320 sounds better.

 

All the time people talk of Manual 300zx = 300bhp and auto = 280 but we both know RWHP is more like 240 and 220, but even that doesn't show a true picture because the Auto's torque curve is such that it is quicker 0 to 80 than the manual. If you have the knowledge then please remember we all talk fly when were first getting into it and people ask because they don't know and want help.

Thank's for the advice going to keep the cats in the turbo's have only done 25K BUT my mate had his out ALOT of smoke. i will do the pad's and disc's 1st. It's at the fly BHP i'm looking at. My old car (Lotus Elan SE) had a P/W of 225BHP/TON (the car was not std) the same p/w in a ZED is about 340-350BHP. But i would like to have moore than my old car. it cost £1k to go from 165bhp to 225bhp is 35%. 35% in the 300 is 378BHP so that's what i'm looking at i need to use the car for work 35miles a day

Hi Marty

 

Sorry if I get prickley at times. Just too many people on hear want to poo poo lads who are trying to improve the performance of their cars on a limited budget. Most people until they get involved with the serious tuning bug speek Fly. They talk about the new 2.5 Scooby being 320 bhp when infact power to the wheels in about 240bhp which still swishes it along, but 320 sounds better.

 

All the time people talk of Manual 300zx = 300bhp and auto = 280 but we both know RWHP is more like 240 and 220, but even that doesn't show a true picture because the Auto's torque curve is such that it is quicker 0 to 80 than the manual. If you have the knowledge then please remember we all talk fly when were first getting into it and people ask because they don't know and want help.

 

Yup not a problem Mark, though i also try and remind them that the 300bhp and 280bhp were factory figures, and with cars approaching 15 years of age their engines ar'nt realistically gonna see those figures :(

 

Its always good to get your car along to a dyno day (cheap power run) and get a good starting power figure before doing any modding. Then you can clearly see how well it repsonds to mods when you get it re dyno'd - im sure ive read a million "disapointing dyno run" threads in my life due to people using staged charts as an overall estimation, especially if they had no pre mods performance figures.

 

And as you have said, the most important thing to consider is the health of your engine and components in thier current state. If in doubt - check and replace things that you seem unsure off, get a good diagnostics check, compression check etc etc

 

and in agreement, Generic maps available such as those from Andy-p and DTA all have a degree of safety built into them, which means they usually run slightly rich but with all generic fueling/timing maps, some cars respond better than others. They are a great way to get into tuning as they are cost effective and proven to work. If you want something tailor made to suit your engine and mods specifically, then the likes of John dixxon can Custom map to your needs - downside is the cost.

 

Marty

Yup not a problem Mark, though i also try and remind them that the 300bhp and 280bhp were factory figures, and with cars approaching 15 years of age their engines ar'nt realistically gonna see those figures :(

 

Its always good to get your car along to a dyno day (cheap power run) and get a good starting power figure before doing any modding. Then you can clearly see how well it repsonds to mods when you get it re dyno'd - im sure ive read a million "disapointing dyno run" threads in my life due to people using staged charts as an overall estimation, especially if they had no pre mods performance figures.

 

And as you have said, the most important thing to consider is the health of your engine and components in thier current state. If in doubt - check and replace things that you seem unsure off, get a good diagnostics check, compression check etc etc

 

and in agreement, Generic maps available such as those from Andy-p and DTA all have a degree of safety built into them, which means they usually run slightly rich but with all generic fueling/timing maps, some cars respond better than others. They are a great way to get into tuning as they are cost effective and proven to work. If you want something tailor made to suit your engine and mods specifically, then the likes of John dixxon can Custom map to your needs - downside is the cost.

 

Marty

 

The engines in Nissan 300zx's and Nissan Skylines are perfectly balanced, which reduce vibration and other stresses, which improve performance, effeciency and reliability of the engine as wear is reduced.

 

The benefits of having a balanced engine is that they should maintain their BHP even with a 15 year old car as long as the engine has been kept in good condition.

a lot been said already but i wanted to jump in just to get some balance.

 

I have spent the last year+ 30,000 miles getting into my 300TT and a lot of wallet already making it better.

I am no big expert by a long way but what i have learned so far can save a lot of cash. I won't talk BHP yet as in my humble opinion the best initial upgrade you can do for a Z in real world driving is the following in the order. This is the order I WOULD have gone if i had truly known the car and wanted maximum real world result for my cash. This R & D has been verified by my track day experience and what worked or didn't for my car.

 

1. HID headlight upgrade - Standard lights are like glow worms in a jam jar and unsafe for the performance of the car. This was the best upgrade in terms of performance per £. Made me feel safe to drive sportingly at night. If you do a lot of night driving get it done now.

2. Big Brake upgrade - The stock car is woefully underbraked and one true emergency stop and the discs warp. I spent too much wallet on stock size discs upgrades and pads when if i had known I would have gone straight to the big brake kit. (assumes you have bigger wheels - 17's for best handling 18's if you want looks - and good rubber already)

3. Uprated front and rear anti-roll bars - made a big difference to handling and cornering speed. - A great real world performance upgrade and low cost too. Jap spec are especially puny

4. Uprated and lowered springs - again great performance upgrade for low cost

4a) Replacement dampers (again stock ones will be way tired by now)

 

I would do all of these things with the stock car before i went for horsepower knowing what i know now ! :rolleyes:

 

Now the car is fast and safe and handling well then it is worth talking BHP

 

5. Major service at a specialist (zedworld, ztech etc.) including a full compression test to ensure all is well so you can be sure that that 60k service (that everyone says they have done before you buy) has really been done. You should have seen the cambelt :rant: that came out of my import that had just had its 60k service - honest gov! :x:

Do a baseline dyno run. So many people don't do this. get it done is my advice

IF an Auto car add autobox cooler ASAP and don't fit an HKS ALC it will only hasten the end of the std box.

6. Induction kit

7. Exhaust and de-cat (i know about de-catting but lets face facts everyone who owns this car is gonna have to replace the turbo's soon anyway unless you have already done it or bought one with proof that they have been done. Anyone who buys a Z now and thinks not is in denial just start saving)

8. Colder plugs safety for the next step

9. New turbo's (and autobox re-condition if an auto - you may has well have it done while the engine is out anyway)

10. Chip (John Dixon, JWT, Mines,etc.)

11. Boost controller to 1 bar no more

12. Intercoolers

 

That is as far as you need to go to get somewhere near to what you asked for. It will be more like 350bhp real world than 400bhp but your car will go, stop, handle better, be safer and not blow apart either.

 

Chris

a lot been said already but i wanted to jump in just to get some balance.

 

I have spent the last year+ 30,000 miles getting into my 300TT and a lot of wallet already making it better.

I am no big expert by a long way but what i have learned so far can save a lot of cash. I won't talk BHP yet as in my humble opinion the best initial upgrade you can do for a Z in real world driving is the following in the order. This is the order I WOULD have gone if i had truly known the car and wanted maximum real world result for my cash. This R & D has been verified by my track day experience and what worked or didn't for my car.

 

1. HID headlight upgrade - Standard lights are like glow worms in a jam jar and unsafe for the performance of the car. This was the best upgrade in terms of performance per £. Made me feel safe to drive sportingly at night. If you do a lot of night driving get it done now.

2. Big Brake upgrade - The stock car is woefully underbraked and one true emergency stop and the discs warp. I spent too much wallet on stock size discs upgrades and pads when if i had known I would have gone straight to the big brake kit. (assumes you have bigger wheels - 17's for best handling 18's if you want looks - and good rubber already)

3. Uprated front and rear anti-roll bars - made a big difference to handling and cornering speed. - A great real world performance upgrade and low cost too. Jap spec are especially puny

4. Uprated and lowered springs - again great performance upgrade for low cost

4a) Replacement dampers (again stock ones will be way tired by now)

 

I would do all of these things with the stock car before i went for horsepower knowing what i know now ! :rolleyes:

 

Now the car is fast and safe and handling well then it is worth talking BHP

 

5. Major service at a specialist (zedworld, ztech etc.) including a full compression test to ensure all is well so you can be sure that that 60k service (that everyone says they have done before you buy) has really been done. You should have seen the cambelt :rant: that came out of my import that had just had its 60k service - honest gov! :x:

Do a baseline dyno run. So many people don't do this. get it done is my advice

IF an Auto car add autobox cooler ASAP and don't fit an HKS ALC it will only hasten the end of the std box.

6. Induction kit

7. Exhaust and de-cat (i know about de-catting but lets face facts everyone who owns this car is gonna have to replace the turbo's soon anyway unless you have already done it or bought one with proof that they have been done. Anyone who buys a Z now and thinks not is in denial just start saving)

8. Colder plugs safety for the next step

9. New turbo's (and autobox re-condition if an auto - you may has well have it done while the engine is out anyway)

10. Chip (John Dixon, JWT, Mines,etc.)

11. Boost controller to 1 bar no more

12. Intercoolers

 

That is as far as you need to go to get somewhere near to what you asked for. It will be more like 350bhp real world than 400bhp but your car will go, stop, handle better, be safer and not blow apart either.

 

Chris

 

IMO the most fundimental and almost completely overlooked up grade is a proper set of Tyres. Not Toyo Poxy's, Falkens and all the other rubbish Cheapo tyres. You want Bridgestone S02's They are listed as Porsche only fitment these days but these are the best tyre for the car and were Original fitment. These will deliver unbelievable wet weather handling and amazing dry weather. Lets face it tyres are what keep you on the road. S03's are better in the dry but not as good in the rain

 

Then bushes, Springs and Dampers.

 

Remove HICAS and use something like mintex 1155 compound Pads, or Ferodo fast road.

 

Renew belts, plugs (good irridium type ie HKS or NGK) Water/oil pump, Hoses and water pipes + plenum by pass

 

Full and proper service.

 

Now shes handling and stopping ok and you know that the ancillaries are in good order then if you wish you can start looking at power upgrades.

 

Like everything in life. If you don't have the basics right it will all come unraveled and can be costly to the point of Deadly.

I've got Bridgestone Potenzas on mine. Good tyres.

yeah had so3 on last car good tyre, having a dyno friday to see what bhp i got and go from there.

thank's for all the help, is fitting boost jet's a DIY job? (i know a few thing's on car's) were do you put them?? ZEDWORLD want £350 for 70bhp upgrade (ecu and boost jets) my mate has this on his car is it any good? is it a good price? are zedworld anygood?, sorry about all the Q's just want the best for my zed. someone said i should try andyp

thank's for all the help, is fitting boost jet's a DIY job? (i know a few thing's on car's) were do you put them?? ZEDWORLD want £350 for 70bhp upgrade (ecu and boost jets) my mate has this on his car is it any good? is it a good price? are zedworld anygood?, sorry about all the Q's just want the best for my zed. someone said i should try andyp

 

Its not the best way of going because you lack control of boost duty values and have know way of knowing if your spiking. If you go this way you really need a Good Boost gauge and lets be honest the good one such as HKS, Greddy, S.A.P or Defi will set you back at least £200. Cheap Gauges arn't worth shit for imfomation. Only have bling value and make you feel happy till the engine goes bang.

 

So IMO I think going for a Apexi or Greddy boost contoler, that has the built in abillity to map your duty and gain for every gear (you don't want big boost in 1st) + will warning if you spike, give digital accurate readings, will allow you to increase or decrease boost if you do further upgrades, but most importantly protect your car. Is the best option and proberbley only cost about the same, But could save you thousands.

 

I know people who run cars for ever with bleed valves, but were only talking 2 to 3 psi up on standard before your heading towards "there's a hole in my piston dear Lyeza". With a good boost controler and chip your looking more like 6 to 7 psi up on standard before its on the edge because the flow is managed.

 

£300 boost controler and JD or AndyZ will not charge that much to Socket and chip you ECU.

 

Its well worth saving a week or 2 more and have confidence that the smile factor isn't going to lead staight to the Bank managers office with a tube of KY jelly.

Lots of very good advice in this thread, and good to see a thread thats going into depth on performance modding :) The bits about suspension and brakes are especially good. I know few people will take heed as they like to say how much power they have, but in terms of how much enjoyment you get out of driving the car I reckon these things are one of the most valued upgrades you could do. I guess if people have a couple of grand spare they are more likely to spend it on the engine though.

Dave

Mark someone told me on boost jet's you still have saftey boost but on controler you don't and ya more likely to go bang.

Mark someone told me on boost jet's you still have saftey boost but on controler you don't and ya more likely to go bang.

 

Think about this. A bleed jet is basically a small hole on your accuator (wish I could spell) line to bleed of pressure so the waste gate stays closed longer and allows more presure to build in the system before waste gate is forced open ie boost. Even at it most complexed it has a pre set £50 Valve system, but no control.

 

A boost controler uses a small computor to mesure the presures and constantly corrects as is needed. It is also conected to your ECU so if there is a problem it flags up a warning and displays just what is happening. The jets will bleed at the same rate as the hole size allows wether the ECU is switching to Safety mode or not and therefore you'll still be producing the same Boost and Fooking your motor up.

 

Maybe someone could explain it better, but that is my understanding of it.

 

I wouldn't go that way. cheap power usually ends in tears. Which is exactly why Boost controlers were invented in the first place. No good getting to the front of a race only to go bang and not finish.

 

Stop listening to that little Demon saying "Go for the Jets. It's Cheaper and you can have it now. It'll be alright. GO ON"

Think about this. A bleed jet is basically a small hole on your accuator (wish I could spell) line to bleed of pressure so the waste gate stays closed longer and allows more presure to build in the system before waste gate is forced open ie boost. Even at it most complexed it has a pre set £50 Valve system, but no control.

 

A boost controler uses a small computor to mesure the presures and constantly corrects as is needed. It is also conected to your ECU so if there is a problem it flags up a warning and displays just what is happening. The jets will bleed at the same rate as the hole size allows wether the ECU is switching to Safety mode or not and therefore you'll still be producing the same Boost and Fooking your motor up.

 

Maybe someone could explain it better, but that is my understanding of it.

 

I wouldn't go that way. cheap power usually ends in tears. Which is exactly why Boost controlers were invented in the first place. No good getting to the front of a race only to go bang and not finish.

 

Stop listening to that little Demon saying "Go for the Jets. It's Cheaper and you can have it now. It'll be alright. GO ON"

 

The Blitz Dual SBC Spec R and Spec S are electronic boost controllers and dont connect to your ECU. It connects directly to the actuators.

 

However, buying a boost controller that does connect to your ECU sounds a very sensible idea, but would be a lot harder to fit and I wouldnt be prepared to DIY

The Blitz Dual SBC Spec R and Spec S are electronic boost controllers and dont connect to your ECU. It connects directly to the actuators.

 

However, buying a boost controller that does connect to your ECU sounds a very sensible idea, but would be a lot harder to fit and I wouldnt be prepared to DIY

 

Are you sure? because the Apexi and the Greddy Profec both splice into the ECU loom. Where else are they going to get the signal from to say when actuator should be opening and at what psi so as to over ride it with new instructions.

 

As far as I was awhere the Vacunm feeds to the actuators where blocked off and replaced with a single feed taken to them via a T peice with a selenoid controled bleed that is wired to the control unit, Which recieves the signals from the ECU and controls the selenoid bleed using the reprogramed information.

 

Its easy enough to do as every ECU cable port is numbered so either Car specific controler instructions tell you what to splice into or they say which circuit to splice into and the Wireing diagram on the online workshop manual will tell you which number cable those curcuits are.

 

PS as where talking technical specifics I could be talking utter bollcox.