[zookvitara]

hey guys, i am thinking of possibly supercharging or turbocharging my J20A. has anyone attempted this before or have any info on it?

Im not planning on much boost, maybe about 6psi? i dont want to have to touch the internals of the engine but im guessing id need larger injectors and a bigger fuel pump??

any input on this would be great.

cheers.

[atari4x4]

make 2...

i've always thought about slapping a SC14 supercharger on my j20a

[Fatzook]

atari4x4 wrote:

make 2...

i've always thought about slapping a SC14 supercharger on my j20a

Eaton M45

I have one here but it will be 12 months before I look at making a kit for my J20

zookvitara: What is your budget? You should set aside atleast $5k to do it properly. But in reality it will probably cost you more like $7k unless you can do most of the fabwork yourself.

Pete

[zookvitara]

i dont have a heap of cash to throw at it, but yes, all the fab work will be done by myself (if i do it...). if i need to change the ecu or do internal engine work i wont bother.

cheers.

[Fatzook]

zookvitara wrote:

i dont have a heap of cash to throw at it, but yes, all the fab work will be done by myself (if i do it...). if i need to change the ecu or do internal engine work i wont bother.

cheers.

you may have to do both.

There is no way your fuel system, or ECU will be up to the task of fueling a turbo. At the very least you will need a fuel and timing piggyback ECU, and this is a bandaid really. A complete ECU change would be the best for engine longevity AND performance.

And if you are running more than 6 or 7psi boost there is a chance the factory internals won't cope. In that case its better and cheaper to crack the motor open and do the necessary mods BEFORE running the turbo. This may save you some money as your block and pistons won't melt together.

Pete

[ODA1]

i had always thought about running a air pipe from the box to the front for air to be rammed in the faster you go but i was always unsure about the off road aspect, Zuknutters internal snorkel solves this problem and i think it could help

[Fatzook]

ODA1 wrote:

i had always thought about running a air pipe from the box to the front for air to be rammed in the faster you go but i was always unsure about the off road aspect, Zuknutters internal snorkel solves this problem and i think it could help

I doubt it would be a measurable increase in power. I'd put money on it being less than 2kw at wheels.

The only way to make power is to remove restriction, and incearse volume of air and fuel in combustion chamber. Or a different Cam if you go down the NA road.

[dezook]

The factory ecu can cope with up to 6 P.S.I. of positive pressure before it needs to be upgraded. So if you are running say a sc14 supercharger with the standard factory toyota pulley and a boost gauge, You will have no worries with ecu/injectors unless you go stupid with the boost. The manufacturers allowed a small amount of leeway with this and from prior experience sc14's are a good option if you want just a little more power without the big cash outlay on new ecu's/injectors ect. All I can say is give it a go, I'm whacking one on my H25a as tight as it is in my engine bay, I'm just going to be watching the boost to make sure it's within parameters. You can also set the sc14 to disengage the drive to the supercharger on idle too with a microswitch fitted to the throttle. Sc14's are only about $400 and if you are doing your own fab work it shouldn't cost much more than $700 all up. Hope this is helpful.

[JrZook]

dezook wrote:

The factory ecu can cope with up to 6 P.S.I. of positive pressure before it needs to be upgraded.

Where did ya get that info? What fueling management system does the J20A have, MAF or MAP?

Dan

[dezook]

That info. is from personal experience. I saw a guy in brisbane once put a sc12 on a 3ltr. pajero with no mods and that thing was insane. If the vehicle leans out which is rare unless as I said you exceed the 6-8psi area than you simply place an extra injector and dummy drive it to a micro switch on the accelerator. Playing with this stuff yourself you will find a lot of these things out. You don't always have to do things the expensive way. There are always other options

[Fatzook]

dezook wrote:

The factory ecu can cope with up to 6 P.S.I. of positive pressure before it needs to be upgraded. So if you are running say a sc14 supercharger with the standard factory toyota pulley and a boost gauge, You will have no worries with ecu/injectors unless you go stupid with the boost. The manufacturers allowed a small amount of leeway with this and from prior experience sc14's are a good option if you want just a little more power without the big cash outlay on new ecu's/injectors ect. All I can say is give it a go, I'm whacking one on my H25a as tight as it is in my engine bay, I'm just going to be watching the boost to make sure it's within parameters. You can also set the sc14 to disengage the drive to the supercharger on idle too with a microswitch fitted to the throttle. Sc14's are only about $400 and if you are doing your own fab work it shouldn't cost much more than $700 all up. Hope this is helpful.

Please back up these statements with quantifiable data.

I personally know that suzuki sizes their injectors very close to maximum requirements of the FACTORY setup. I had my baleno and vitara injectors flow tested and both were found to be at 90% duty cycle under factory NA conditions. This left room to fuel for about 2psi of boost. The factory ECU may learn to fuel more, but from my experience, and by talking to several aftermarket tuners, and dyno shops, it cannot compensate for 6psi of boost. This does not account for timing changes that must be made at different RPMs aswell.

Telling someone that they can strap a supercharger onto their factory car and run Xpsi boost without backing it up with supporting data is very irresponsible.

JMO
Peter

[dezook]

"That info. is from personal experience."


Why don't you read, I had a feeling you would ark up about this. Not everyone wants to spend a million dollars on mods. I merely stated that I found from personal experience that it's possible. I have never put a car on a dyno yet but have enjoyed modding many cars. Deal with the fact that others will have different opinions to you and don't get so offensive. Back to the topic at hand. I say give it a go if you want, But that is entirely up to you......

[Ben_Sierra]

dezook wrote:

"That info. is from personal experience."


Why don't you read, I had a feeling you would ark up about this. Not everyone wants to spend a million dollars on mods. I merely stated that I found from personal experience that it's possible. I have never put a car on a dyno yet but have enjoyed modding many cars. Deal with the fact that others will have different opinions to you and don't get so offensive. Back to the topic at hand. I say give it a go if you want, But that is entirely up to you......

So what you are saying is you have no evidence to back up your claims of "6 PSI, she'll be right mate"...?

[JrZook]

JrZook wrote:

dezook wrote:

The factory ecu can cope with up to 6 P.S.I. of positive pressure before it needs to be upgraded.

Where did ya get that info? What fueling management system does the J20A have, MAF or MAP?

Dan

[Fatzook]

dezook wrote:

"That info. is from personal experience."


Why don't you read, I had a feeling you would ark up about this. Not everyone wants to spend a million dollars on mods. I merely stated that I found from personal experience that it's possible. I have never put a car on a dyno yet but have enjoyed modding many cars. Deal with the fact that others will have different opinions to you and don't get so offensive. Back to the topic at hand. I say give it a go if you want, But that is entirely up to you......

I read your initial statement and nowhere did it say that your comments were based on "personal experience", nor did you state that you had neverhad a car tuned on a dyno to check that the fuel mixture was correct, or even had a wide band O2 sensor hooked up to check fuel.

And technically I was being Defensive, not offensive, but perhaps you could consider that your information could be used by someone with less technical skill and knowledge than you have; which could very easily result in a melted motor?

[JrZook]

So anyway trying to add in some actual tech instead of arguing the point back and forth .

If the J20 stock fuel management system is MAF based it will be able to account for slight boost provided the MAF sensor isnt on its limits already (which they very rarely are) as it directly measures the airflow.

MAP based on the otherhand will use a 1BAR MAP sensor for n/a engines and hence once atmospheric pressure is reached (WOT) within the intake the sensor is saturated. You have reached the maximum injector pulse width here.

O2 sensor closed loop feedback can provide the information for the comp to self adjust the mixtures back to the ideal 14.7:1, typically between 10-75% throttle with light throttle changes. Out of that range the fueling calculations come directly from the MAF/MAP inputs. 14.7:1 is for ideal burn but this will have to drop to 12-13:1 under WOT, full boost to keep combustion temperatures lower.

A rising rate fuel regulator is required to keep the fuel pressure differential over the injector consistent from vacuum to full boost. Here many use greater than a 1:1 reg on stock ECU's ie 1.5-2:1 to increase the fuel pressure and hence increase the fueling under boost. Far from ideal as its kind of a stab in the dark un-calculated extra fueling approach but has been somewhat successful in keeping a few boosted NA engines with stock management alive.

This accounts for the fueling but another critical parameter is the ignition timing. Pre-ignition kills an engine, pre-ignition kills a boosted engine alot quicker! This uncontrolled burn can bring combustion pressures upward of 300% and thus melt and destroy pistons. An overly rich mixture can combat pre-ignition but again far from ideal although in most cases it will work. Does the J20 have a knock sensor? This may be able to help by knocking back the timing but the simple knock sensor only works over a limited range of RPM.

Each engine is vastly different to another in terms of how it will react to boost from its otherwise n/a guise. This comes down to its CR, cams, size etc as well as the management system MAP/MAF, fueling calcs, dynamic timing etc. So what may work on one engine/management system may not work the same on another.

Anyway just giving out a bit of underlying info and facts, not saying it will or wont work on the J20A. If you do want to go ahead with it id suggest getting it on a dyno asap and actually see whats happening and if it is coping before its time for a new engine. There are a few tricks that can be done to increase fueling from the stock ECU and fuel system that can help and may be adequate but an aftermarket comp and a good tune would get the most power and life out of any boosted engine.

My 10c,
Dan

[zookvitara]

cheers for the replies guys, although id love some boost im now thinking it may end up being an expensive project and could result in a sad engine...

[steve]

It might be cheaper to put a bigger motor in

[neofitou]

How about an NA tune? Putting J18A Pistons and a cam in to up the CR and run premium? anyone?

[Ferrit]

Ever considered a megasquirt?

[2stroker]

Ever considered an 3cyl 2stroke boosted by a strong tail wind.........

[Hybrid]

Ferrit wrote:

Ever considered a megasquirt?

I'm running a megasquirt and have an SC12 at home that I've planned on putting on my G16 for like 2 years now. It's good to be able to look at real time data on injector duty and AFR. I'd planned on running GTI injectors as I can get a set from Damo and there's guys running a lot more horsepower on those injectors stock than I'm planning on. After reading about suzuki running pretty close to the max with their injectors though I'm not so sure it's going to work. I'm going a max of 7-8 psi.

Fatzook wrote:

Eaton M45

I have one here but it will be 12 months before I look at making a kit for my J20

I only know the M45 from the 1.3 minis. Are they really suited for the larger J20? I would have thought an SC14 would be more suited with the SC12 coming in a close second. Yes, I know the M45 is a better design .

JrZook wrote:

MAP based on the otherhand will use a 1BAR MAP sensor for n/a engines

I thought there was a few N/A MAP based cars getting around that use higher than 1Bar map sensors. Toyota surf rings a bell. For tech purposes (as I'll never have a J20) how would someone check that the stock MAP sensor really is 1Bar limited ?

[JrZook]

Hybrid wrote:

JrZook wrote:

MAP based on the otherhand will use a 1BAR MAP sensor for n/a engines

I thought there was a few N/A MAP based cars getting around that use higher than 1Bar map sensors. Toyota surf rings a bell. For tech purposes (as I'll never have a J20) how would someone check that the stock MAP sensor really is 1Bar limited ?

Check the sensor output when engine is not running, should be near some limit of either 0.7v or 4.3v ish.

Dan

[royce]

Man I hate threads where there are heaps of posts that are half wrong and half right, takes to long to quote all the bits out

Fatty, I like how youve made some claims about piston strength and injector sizing and so on based on people experience yet up somebody else for talking about his own experience not being backed up with any data

The 2 litres obviously are a different kettle of fish but I am sure I have read data here found by damo that 1.6 injectors have some room and the fuel pumps are the same part as turbo Subarus so that bits ok

the killer in any engine is detonation and heat, keep the intake cool and the timing right and you could be on a winner

Any idea if the ECU's can be remapped?

[Fatzook]

royce wrote:

Fatty, I like how youve made some claims about piston strength and injector sizing and so on based on people experience yet up somebody else for talking about his own experience not being backed up with any data

I'll try and find the flow test printouts

Any idea if the ECU's can be remapped?

If anyone know this Dan will. He's a bloody rocket scientist

[Hybrid]

royce wrote:

Any idea if the ECU's can be remapped?

Thought I'd do some google bludging to get out of work. The J20A's ECU and ID number appears to be 1902 = 33920-65DA1 (From http://www.activeboard.com/forum.spark? ... D=30458340)

In another thread they say the ECU is a Hitachi H8 derivative. Only the F designation model can be flashed but its processor can be installed in the other 2 so that they too can be flashed.

See here - http://rhinopower.activeboard.com/forum ... D=30904358

[losfer]

If you want my opinion here it is ....

for 6psi of boost , your injectors will be fine , you fuel pump will be fine , the engine will be fine , but dont fuck around with the stock ecu .. go aftermarket.

engine failures ive seen have been from dodgy engine management , not the engine itself. (aftermarket chips / ecu flashes etc)

[JrZook]

losfer wrote:

If you want my opinion here it is ....

for 6psi of boost , your injectors will be fine , you fuel pump will be fine , the engine will be fine , but dont fuck around with the stock ecu .. go aftermarket.

engine failures ive seen have been from dodgy engine management , not the engine itself. (aftermarket chips / ecu flashes etc)

So what size injectors does it run and whats the max duty cycle they run at in stock form?

[fordem]

Hybrid wrote:

royce wrote:

Any idea if the ECU's can be remapped?

Thought I'd do some google bludging to get out of work. The J20A's ECU and ID number appears to be 1902 = 33920-65DA1 (From http://www.activeboard.com/forum.spark? ... D=30458340)

In another thread they say the ECU is a Hitachi H8 derivative. Only the F designation model can be flashed but its processor can be installed in the other 2 so that they too can be flashed.

See here - http://rhinopower.activeboard.com/forum ... D=30904358

Just so that you're aware of it - Suzuki used different ECUs for the different export markets - yours may be different.

Those links take you to the details of the ECU from an E06 spec (Africa market) J20A engined SQ420 '98 Grand Vitara - Australian market (E24) may carry a different ECU, and the same goes for the other markets.

[losfer]

JrZook wrote:

losfer wrote:

If you want my opinion here it is ....

for 6psi of boost , your injectors will be fine , you fuel pump will be fine , the engine will be fine , but dont fuck around with the stock ecu .. go aftermarket.

engine failures ive seen have been from dodgy engine management , not the engine itself. (aftermarket chips / ecu flashes etc)

So what size injectors does it run and whats the max duty cycle they run at in stock form?

surprisingly , the workshop manual doesnt specify injector duty cylce for the j20 so i cant give you definitive figures , but i have first hand experience in boost on all g-series engines , i have a colleague who has boosted j-series engines. I can ask them what was the limit before the injectors needed to be changed if you want ? but it was definately beyond 6 psi ..