18 pounds of boost

[Andre]

i fitted a manual boost controller on my car today . i tested the boost controlller after a few runs, i decided to raise it some more it went up to 20 pounds then it started to starve for fuel. so i put it at 18 pounds . the car is working good . the thing is i don't have a fuel cut defencer or any other stuff like that a ll i have is exhaust mods . why am i so lucky ?

[richieelliott]

18 psi? brilliant! who knows why you dont dont grumble!

[richieelliott]

but that only just over one bar so its not too high 17.7 psi - 1 bar i thiink so thats not excessive yeti think thats similar setup to pete and daves electronic boost setup? And dave only hits fuel cut on cold days

[Spirit]

1 bar = 14.50 psi so 18psi = 1.24 bar - a little more than mine. Run at 1.0bar tops myself although it sometimes spikes to 1.05 (where my overboost protector cuts in and knocks it back)

[richieelliott]

14.5 yes what was i thinking am only a monkey

[Andre]

What is the safest/ highest boost pressure that i should set the car to on standard internals?

[Nick Mann]

I think one member in particular has done a large number of miles at about 18 psi. I'm sure he will let you know next time he is online. The issue is leaning out/detonation... I'm lead to believe that if you can monitor the air/fuel ration then you can keep control. I'm also lead to believe that the stock internals are very strong.

[pjjohnson]

Safest/highest ? don't know but I ran at 1.1 or 1.2 bar without problems for many miles with std internals. Had problems at 1.4.

[stonegr]

Safest/highest ? don't know but I ran at 1.1 or 1.2 bar without problems for many miles with std internals. Had problems at 1.4.
What kind of problems mate ?

[pjjohnson]

Turbo problems on a track day.
Pop, clouds of white smoke, no boost.
Tips of the turbos had gone AWOL, maybe melted according to Well Lane who did the work for me. Had to have one new turbo and one reconditioned

[stonegr]

Turbo problems on a track day.
Pop, clouds of white smoke, no boost.
Tips of the turbos had gone AWOL, maybe melted according to Well Lane who did the work for me. Had to have one new turbo and one reconditioned

:(
So safety limits for stock turbo is 1,2bar ;)

[pjjohnson]

Well, when I'm driving my computer I think that 1.1 bar gives as good performance as 1.2+ bar, so I shouldn't feel the need to run anymore than 1.1 to get good safe performance.

Then I get in the car and drive it and notice someone has set at 1.25 bar, with safety cut out at 1.35.

Who could that be ?

Weird.

[Mante]

remember guys we have tiny turbo's like someone mentioned going up to 18 is possible but effective boost is at max 15psi...thats what 1.2 bar or so not exactly sure.

Those problems pjjohnson were caused by pushing the 9b's past there effectiveness. Upgrade, get in touch with a gto owner that has a set of 13bs then enjoy that for awhile. I ran at 20psi with no real great improvements, reality kicked in and I dropped it back to 15

[FTOLTD]

i was running mine at 18 lb boost for about 3 months and then melted the tops of two pistons doing over 250 kms an hour when the feul leaned out and got some detonation,

be carefull unless you want to replace engine or do rebuild

[KiwiMR2]

Up to what boost setting does the factory ecu have fuel maps for?? and at what level should the FC kick in?

Cheers
KiwiMR2

[richieelliott]

does the gto turbos fit the vr4?

[Mante]

does the gto turbos fit the vr4?

I believe so, they come with 13b's stock. Due to our motors being reversed 180 degree's we would use there front turbo on the rear of our motor. I have not confirmed this yet but once a buddy of mine upgrades I will be able to do all the test fitting.

[Nick Mann]

Would be interesting to find out, as I have heard they don't fit... Bigger turbos that are easily obtainable would be interesting to many!

[Mante]

Once the spare 6a13 is pulled and can be compared to a GTO/3000gt then that will satisfy my curiosty. I have also heard they dont fit but the person could nto give me a reason why they didnt fit...He "heard" it from someone. Thats not good enough for me!

[pjjohnson]

Anything can be made to fit.

All that varies is how much work you have to do to make it happen.

[Nick Mann]

Good luck! Let us know.

[Mante]

Anything can be made to fit.

All that varies is how much work you have to do to make it happen.

the gto/3000gt's 13b's got my attention because I really dont have the $$ to get manifolds made for td05 housing. So finding something that "bolts" up would be great!

[enigma]

Once the spare 6a13 is pulled and can be compared to a GTO/3000gt then that will satisfy my curiosty. I have also heard they dont fit but the person could nto give me a reason why they didnt fit...He "heard" it from someone. Thats not good enough for me!

The gearbox is on the other side for a start!!!!

[Nick Mann]

Due to our motors being reversed 180 degree's we would use there front turbo on the rear of our motor. I have not confirmed this yet but once a buddy of mine upgrades I will be able to do all the test fitting.

Read this bit, BDA!!

[KiwiMR2]

Up to what boost setting does the factory ecu have fuel maps for?? and at what level should the FC kick in?

Cheers
KiwiMR2

Nobody know the answer to this?? :sick:

KiwiMR2

[Mante]

Nobody know the answer to this?? :sick:

KiwiMR2


I dont believe I can answer that because Im running on only 94 octane, my vr4 is pretty much running on thin ice.

Worst way to find where the fuel cut is...up the boost until either 2 things will happen. You reach the fuel cut, which the car should do first OR the worst side, your motor is done. I personally have hit the fuel cut, rev limiter and speed cut within 2 months of ownership lol

[enigma]

Nobody know the answer to this?? :sick:

KiwiMR2

Fuel maps will not run to 18psi, and boost cut is not all that dependant on boost, it is more to do with the mass of air entering the engine. I have had boost cut at 11psi on a cold day. The car does run rich anyway so even if the maps do not support higher boost the chance of leaning out is slim, also the o2 sensor will detect to some extent a lean mix and add fuel as appropriate. The more obvious question is how much can the stock injectors and pumps handle?

[Nimma]

The fuel cut kicks in at a set airflow rather than a set pressure. Thus if you have standard intake exhaust intercooler etc. you are likely to have fuel cut at a lower boost. Anything over 1 bar with the standard turbos and all they will really be doing is pushing hot air and not making anymore power.

The lower the fuel cut kicks in, the better the airflow your car has... unless you have a split intake pipe :p

Colder, denser air will also make the fuel cut come in lower

[KiwiMR2]

and boost cut is not all that dependant on boost, it is more to do with the mass of air entering the engine


The fuel cut kicks in at a set airflow rather than a set pressure.

How does it do that?......this is a VR4 legnum thing obviously, or do the VR4 galants do it to??

Cheers
KiwiMR2

[Nimma]

Same engine. Once the MAF (mass air flow meter) meets a specific max voltage which correlates to near the peak mass air flow the hot wire can handle, the ecu will cut ignition... MAF cut. It just so happens that the peak airflow in any one car correlates quite well with boost at maximum load. This is why you can get fuel cut at lower boost in cars with better intakes and exhaust. Also, in cold weather air is more dense and so boost will be lower before the cut comes.

Bottom line is the point at which it cuts relates best to maximum torque allowable by the MAF.

[KiwiTT]

Why not go the whole hog. They have 3 litre 8G Galant in the US, maybe the GTO with Turbos can mount inside the engine bay.

[Mante]

I feel that I just learned something :stunned:

[-LegnumVR4-]

The TD04 GTO turbos will not bolt straight up to the VR-4. One model of TD04 and turbine housing will bolt straight up to the VR-4's manifold. You would have to make up new pipes to the intercooler (the pipes on top of the engine) because the outlets are different on the turbos.

It's then just a matter of checking space u have to fit the turbos front and back, heat sheilds etc. I didn't get to see them mounted on an engine to check.

Exhaust at the dump pipes would have to change to suit new setup.

Oil lines and coolant lines may have to change.

Rhys