VR4 16psi and 139kw@wheels??!!

[nonickname]

Please help! :blink:

91 vr4 run on dyno holding 16psi and only putting out 139kws.

a/f ratio perfect.
timing is spot on

motor is fresh rebuild.

tdo5 20g, evo 9 injectotrs. 055, walbro fuel pump, adjustable fuel pressure reg and ecmlink

The car had a meek chip when I bought the car. It idled high and ran rough and very rich but pulled fairly well on only 14psi.
I took it to a workshop to have an ecmlink installed and tuned properly. It now has the ecmlink installed and runs nice and smooth, idles fine but even running at 16psi it has way less power than it had before on less boost?

At the time I had a Greddy profec b ebc installed. Is it possible that I could have a leak on this unit somewhere? My boost gauge is plumbed into the inlet manifold correctly and has not been touched so I think I can eliminate a leaky gauge. It is showing the car is holding 16psi with no spike.....BUT is it possible the car is not really holding that pressure??? It really does feel more like 5-8psi max to me. I bypassed the ebc from the wastgate (like a factory set up) and the car creeps from 6psi to maybe just over 10psi when the revs get up at redline. It doesnt seem to go that much slower but still dosnt feel right to me. Im about to rip out all the intake pipes, vacuum hoses and check them all 2moro hoping that is the issue but im really not convinced to be honest.

Just to elimate a few things

New clutch set up so def not slipping
Cat is not clogged up or blocked (dropped whole exhaust)
The car had a manual boost controller before ebc install and ran bang on 14psi and pulled all the way past redline

I have full faith in the tuner I used and am happy with all his work on the car so far. But sometimes cars have little problems that are just odd and I believe I have come across one here lol

Any input would be appreciated!

 

[CLuTZ]

Something is wrong if you're not able to pump 20+ psi and some timing into it, that's for sure.

Do you mind sharing with us who did the tuning?

 

[nonickname]

Something is wrong if you're not able to pump 20+ psi and some timing into it, that's for sure.

Do you mind sharing with us who did the tuning?

Id rather not say at this stage. He has done alot of 4g63's and is very well known. He definitley has a few ideas on what to do next. I had to pull the pin at this stage as it was getting alot more pricey than i wanted at this stage. He did say he could get 15-16 degrees out of it but it was knocking at high boost ie over 18psi. I know someting is def not right. But ya do have to ask why it boosted fine before the tune. Two things changed were electronic boost controller and the ecmlink. Its gota be one of the two surely.

 

[CLuTZ]

Id rather not say at this stage. He has done alot of 4g63's and is very well known. He definitley has a few ideas on what to do next. I had to pull the pin at this stage as it was getting alot more pricey than i wanted at this stage. He did say he could get 15-16 degrees out of it but it was knocking at high boost ie over 18psi. I know someting is def not right. But ya do have to ask why it boosted fine before the tune. Two things changed were electronic boost controller and the ecmlink. Its gota be one of the two surely.

I'm not trying to start any shit here- forums are renowned for that, but (theoretically speaking) if I was experienced with 4G's and was asked to tune one with a 20g, I wouldn't be giving the car back to the customer with only 139kw until I found out why it's not making some better numbers than that.....?

Nothing worse than giving your car to someone along with a wad of cash, and you get it back and you're disappointed

 

[nonickname]

I'm not trying to start any shit here- forums are renowned for that, but (theoretically speaking) if I was experienced with 4G's and was asked to tune one with a 20g, I wouldn't be giving the car back to the customer with only 139kw until I found out why it's not making some better numbers than that.....?

Nothing worse than giving your car to someone along with a wad of cash, and you get it back and you're disappointed

I agree. First of all I had to pull out purely due to my poor budget lol. He really wanted to press on and solve the problem. I just dont want people to get a bad impression of this workshop. I will say they have alot of 4g63's above 200kw@wheels and some above 300 to their name so thay are good at what they do. When the vr4 puts out a decent power figure i will then gladly state who has done the work

 

[CLuTZ]

They should have solved the problem- that's what you paid them for. I'm even feeling disappointed for you! :lol:

And they expect you to come back with some more cash so they can "sort it"?

 

[nonickname]

They should have solved the problem- that's what you paid them for. I'm even feeling disappointed for you! :lol:

And they expect you to come back with some more cash so they can "sort it"?

I fully get what you mean. Just to clarify though. The engine was not built there. The build of the motor is solid but whoever did it was a bit sloppy in some other areas. The car is now in perfect condtion mechanically- bar the boost issue. so i dont want to take any cred away from him. He suspects the cams or pulleys could be wrong ones etc or maybe the block/head has been shaved too much and possibly raised the compression too high.....he cant tell without going deeper as he did not build the motor. So at this point it is a case of eliminating everything outside the engine. Yes it is a pain in the arse but I have fair mechnical knowledge myself and can tell this one is a bit odd.

Any ideas???

 

[CLuTZ]

Have you triple checked the base timing? If it's a tooth or 2 out, you could be having dramas. Surely they would have checked that though?

What is the head from?

 

[nonickname]

Have you triple checked the base timing? If it's a tooth or 2 out, you could be having dramas. Surely they would have checked that though?

What is the head from?

Yes all checked and perfect. Head is factory vr4. None of the internals were adjusted or touched while getting tuned. It boosted fine before with internals how they are now so could prob eliminate that for now.

 

[iluszn]

I had this issue when i initially had my GSR tuned, It vibrated a little when driving and it didnt matter how much boost and time was spent tuning the car just would not go. It ended up being the balance shaft was out 180degrees. Once I had all belts replaced and that rectified, car boosted fine, no pinging/knocking @ 22psi and made over 200kw. It may be possible that your belts slackened and you jumped a tooth?

Things to try, Remove the EBC and just set your actuator to a vaccuum line and see how the car runs.

 

[mattrat]

ive had the balance shaft out 180 degrees before, car still made over 200kws, physically you can feel the vibration i doubt it can do anything to the engine

 

[nonickname]

I had this issue when i initially had my GSR tuned, It vibrated a little when driving and it didnt matter how much boost and time was spent tuning the car just would not go. It ended up being the balance shaft was out 180degrees. Once I had all belts replaced and that rectified, car boosted fine, no pinging/knocking @ 22psi and made over 200kw. It may be possible that your belts slackened and you jumped a tooth?

Things to try, Remove the EBC and just set your actuator to a vaccuum line and see how the car runs.

Thanks for your input. I have disconnected the ebc today from turbo and inlet manifold. I also changed and clamped everyhose in the bay and also sprayed soapy water to see if any leaks were present. everything seems perfect. In regards to the balance shafts the car runs very smooth and has a good exhaust note. it also had good boost response before the car was put in the shop.

Something to note is the wastegate actuator broke while on the dyno. The arm came of the nut and was loose. It appeared to be stripped so a secondhand one was sourced......Maybe the cause?? I think this will be next on the list.

To sum it all up the car drives smooth, starts first pop. does not smoke or make any odd noises etc. It starts boost at about 8psi and as it revs up it seems to max out at 12psi (with ebc disconnected) It feels like the boost gauge is going up but the engine is playing catch up and getting left behind.

 

[boostboy76]

That's weird. I'm no expert by any means, and trying to learn, so correct me if I'm wrong, but if the wastegate actuator is suspect, that means it might open prematurely and not hold boost properly?

...and would that show up on the boost gauge - i.e. you set it for 15psi, but it doesn't come close to holding that?

 

[nonickname]

That's weird. I'm no expert by any means, and trying to learn, so correct me if I'm wrong, but if the wastegate actuator is suspect, that means it might open prematurely and not hold boost properly?

...and would that show up on the boost gauge - i.e. you set it for 15psi, but it doesn't come close to holding that?

I hope so coz thats an easy fix! lol

 

[iluszn]

If the actuator is opening early, even at 16psi, your car should probably make more power than it has. How soft is the wastegate spring? Have seen where the spring had lost tension so it just opened up without much effort. Compare it to your old one.

 

[nonickname]

Ok Timing belt cover is off. I had a look at the marks on the inlet and exhaust pulleys. At no point will they all line up horizontally. If i put a ruler up against them one is always up or down a notch. Does this confirm that one is out a tooth? It looks to me when the inlet pulley is squared up (markings made horizontal) the exhaust pulley is one tooth clockwise over too far? I have searched old posts and found if the exhaust cam is off the motor will lose alot of power. My only question is why wasnt the car like this before? Did it jump a tooth on the dyno possibly? Seems odd to me.

 

[rob323]

Pressure test the intake.
Post up the datalog from the dyno pull, I'm sure some of the guys here will be able to take a look at it for you.

 

[VR-4Squid]

Ok Timing belt cover is off. I had a look at the marks on the inlet and exhaust pulleys. At no point will they all line up horizontally.

They never ALL line up, because the 2 marks on each pulley aren't exactly 180º apart, but the 2 closest to each other should line up exactly.

 

[bazeng]

I say do all the things you can yourself ie, check inside piping, pressure test intake system and see if you can find any significant issues. Another to try is to check the pressure drop of the intercooler system. You can so this by placing a gauge before the cooler and get max boost on it, then checking it on the other side if the cooler.

 

[EVO-00X]

At rest with the engine left to stop during stroke, the two timing marks wont ever line up. They will be half a tooth out of alignment unless you turn them physically with a spanner to align side by side.
Interesting that most of the things have been covered already and there's still an issue?? You didnt leave a rag in the intercooler piping or anything did you? lol :lol:
Just another thought and off on a bit of a tangent, but when you said your boost gauge is going up but the engine is playing catchup... are you getting any signs that may indicate that your clutch is slipping under load?