M35 Boost - Why Does It Take So Long?

[Paramour]

Hello,

I have noticed that when I put my foot down there is a lag period before the turbo spools up enough to get going. It is ok to live with but as it gets to 4000-4500rpm it changes to next gear, so I dont really get to enjoy the benefits of boosting. I appreciate that is what the triptronic is for to hold it in gear for longer.

My Evo boosts very well and is a manual, I know it is a different car but I want the same excitement from my stag eg feel the boost rush.

Hence my next problem it does not change quick enough for my liking, it takes to long and appears to be slipping. I drove my mates Liberty GT and you hardly notice when you shift the triptronic.

So I would like to pose the following questions to you :

1. Is possible to get it to boost earlier rather than later and still have the same fuel consumption

2. Or do I actually need more boost say 1 bar etc

3. How are the triptronic changes for you guys S1, S2 M35

4. Is there a way to improve the triptronic gear changes

5. Or can you offer any other solution

Jules

[Jetwreck]

LOL....welcome to my world!!! I will clear alot of my answers up at the end.....simplified to start with.

1.Yes(read below though) No to the bottom is complete)

2.Yes

3..5 to 1 second delay(even across the gate in manual shift)

4. Don't know but Nismo sell's an aftermarket ECU which may....cannot read jap though so cannot confirm.

5. Read below

Well there's the short answers.

God bless the rain as I have been slip sliding around town trying to find out power curves and acceleration technic's for my M35(new nick name T-Bone or Da- Steak). What I have found is that if I put my foot through the firewall I go backwards...If I do a small squirt(wait for the boost) and then progressively apply the throttle I can get maximum Torque(sometimes better than HP). Bit frustrating as I have never had this with any car that I have owned in the past. So at the end of the Day you are not on your own with this.....Don't worry I thought I had bought a dud initially then I got to thinking what I needed to sort out...also I found that it's actually faster than it feels as my mate found out in his Turbo Territory....lol.

1. Airflow (Good air filter with the V35 skyline bit at the front of the air filter box(better than a rampod as it deflects the hot air -approx $150 all up)

2. Exhaust (3" with a good dump pipe and high flow cat -$1,100 + Cat and dump TBA)

3. Turbo (High flow and steel impellers - $1,200....good for 13PSI everyday....not ballbearing unless you want it to boost up quicker then add another $400)

4. Boost controller ($500 - $800)

5. Dyno (cannot give you an answer as I get it for free....but extimate would be $150 per hour)

Anyway that's what I have figure out to get the M35 going. Just remember that you have sold this to your wife as a family car(well that's what I did...lol) It's never going to be an R34 GTR....but you can get it to go like shit off a stick in a straight line....pity about the brakes though.

P.S On beer number ? so sorry if I have not made sense.

Edited January 19, 2008 by Jetwreck

[andy65b]

LOL....welcome to my world!!! I will clear alot of my answers up at the end.....simplified to start with.

1.Yes(read below though) No to the bottom is complete)

2.Yes

3..5 to 1 second delay(even across the gate in manual shift)

4. Don't know but Nismo sell's an aftermarket ECU which may....cannot read jap though so cannot confirm.

5. Read below

Well there's the short answers.

God bless the rain as I have been slip sliding around town trying to find out power curves and acceleration technic's for my M35(new nick name T-Bone or Da- Steak). What I have found is that if I put my foot through the firewall I go backwards...If I do a small squirt(wait for the boost) and then progressively apply the throttle I can get maximum Torque(sometimes better than HP). Bit frustrating as I have never had this with any car that I have owned in the past. So at the end of the Day you are not on your own with this.....Don't worry I thought I had bought a dud initially then I got to thinking what I needed to sort out...also I found that it's actually faster than it feels as my mate found out in his Turbo Territory....lol.

1. Airflow (Good air filter with the V35 skyline bit at the front of the air filter box(better than a rampod as it deflects the hot air -approx $150 all up)

2. Exhaust (3" with a good dump pipe and high flow cat -$1,100 + Cat and dump TBA)

3. Turbo (High flow and steel impellers - $1,200....good for 13PSI everyday....not ballbearing unless you want it to boost up quicker then add another $400)

4. Boost controller ($500 - $800)

5. Dyno (cannot give you an answer as I get it for free....but extimate would be $150 per hour)

Anyway that's what I have figure out to get the M35 going. Just remember that you have sold this to your wife as a family car(well that's what I did...lol) It's never going to be an R34 GTR....but you can get it to go like shit off a stick in a straight line....pity about the brakes though.

P.S On beer number ? so sorry if I have not made sense.

Hi Jetwreak

Know what you mean about moving around in the wet. I am going to try the sycro button tomorrow to see if that improves the take off at t intersections.

Did you find out how to get the V35 airbox intake?

I am going to play around with the mesh untill I can get one.

Having come out of manuals for the last 10 years I am just getting used to the Auto aspect. I have been playing with putting the lever to the manual change position but not changing gears. The auto will use lower gears than selected but not higher. Seems a little more agresive in the way it changes. Could just be my imagination though? In many other cars doing this put the car in a "sports" auto mode.

Cheers

Andy

[Paramour]

regardless of what beer you are up to it made perfect sense....

It has been raining all day here in Sydney and near home there is a nice 3 lane road and I came out in a bit of a rush and the backend slid out a bit but it recovered very quickly, so i though I am going to do that again with the Synchro on.... well I did it a little faster and no sliding whatsoever.....

I thought the take offs with synchro were actually better from the lights and the gears did not seem to change as slowly.

Yes it was sold as a family car to the wife...."Thats why you have the evo" she often says, blah I say I just want to make the Stag better.......

This is actually my first Auto turbo car so it is all a little lazy ATM. But I will look into the cheaper mods first like airflow, I reckon that will make a difference.

Jules

[Paramour]

Yes I have to admit it does not have that throw you back in to the seat feeling but once it does get going 100 comes very quickly and 140 even quicker. But it is quicker than a Liberty GT that is for sure..

Sadly the Stagea is Autobahn car I feel, it just wants to do 120-160 all the time with no effort at all.

With all the taxes we pay why cant we have an Autobahn.........

[pixel8r]

Hi Paramour,

Allow me to offer a S2 stagea perspective, and hopefully you will find this helpful as I think there are similarities with what you are experiencing.

First things first...

1. You can do a few things to improve spool up times. The most noticeable difference will come from a 3" turbo-back exhaust (incl high-flow cat) - only make sure you get 2 mufflers, 1 centre, 1 rear (ie. NOT a muffler+resonator setup) to reduce drone as this is a problem with wagons. Make sure your wife is ok with this BEFORE doing it because it WILL be louder than stock, both inside and outside the car. Its definitely bearable and hardly noticeable when cruising at 60km/h but at certain revs it can get a little louder...

Further to this you can advance your timing a little on a dyno (provided its safe to do so) - if its stock you wont be able to change much though...

You can also get a piggyback ecu that can do ignition timing and use this to tune the ignition timing at various rpm points which will make it spool quicker.

Further, you can buy a cheap manual boost controller (turbotech ONLY - do not trust other brands of manual boost controller) from ebay (search for turbotech boost controller) and these will make sure the wastegate stays fully closed as it builds boost, unlike stock where the wastegate may start to creap open as you approach max boost. These controllers do work well for anything under about 14-16psi. I dont have any experience with mine over 12psi so cant really comment other than to say that mine works perfectly - holds boost very solid and doesn't spike. These controllers are not a bleed valve so dont have the spiking risks of those.

2. Raising the boost level is only raising the MAX boost level - so it wont make it spool up any quicker, it just means when it does spool up, it will go a bit further. Remember that boost is actually air PRESSURE and doesn't always increase air FLOW if the system is near its limits. For example - If you have a restrictive exhaust/intake then raising the boost past say 10psi may not make much difference at all, other than putting a lot more pressure on your turbo...

The stock setup should benefit from 10psi of boost and if you upgrade the exhaust this will normally cause your boost to increase as well, by about 2psi or so. Its a good idea to get a boost guage to measure it if the car doesn't come with one...

If the stock turbo is ceramic like the S1's and S2's then you wont want to boost past 10-11psi since the ceramic wheel can shatter at around 14psi. not pretty.

High-flow and larger turbos will often flow more air at the same boost pressure (depending on the boost setting and efficiency ranges) so bear this in mind if you want to upgrade the turbo. This will require some form of ecu tuning however....which I'd recommend in any case. Most electronics like this you can have fully installed and tuned for under about $600-800...depending on which piggyback ecu and tuning workshop you choose.

3. When I bought my S2, I wasn't happy with the time it took to change gears, especially when using tiptronic. Was like 2s from 1st to 2nd sometimes, which is waaay too long for me. I found that the gear changes weren't snappy enough to make the tiptronic worthwhile...so I never used it and just drove round in Drive.

4. YES. My first mod was a "shift kit" - otherwise known as a "valve body upgrade" for your auto transmission. Not sure if these are available for the M35 auto, but if you take it to a reputable auto trans specialist - preferably one who has good experience with high performance autos, they should be able to help out. The shifts will feel a little bit harsher, but mostly unnoticeable when cruising around. Its only when you're driving hard that you notice the snappier shifts - it will shift from 1st to 2nd pretty much instant now. Using tiptronic there is a small delay where the ecu works out what gear you want, and then its instantly in the gear. Its a bit clunky but like the exhaust, its definitely bearable and my wife has never complained about it.

5. just all of the above...

To give it more go, try the 3" exhaust, boost controller & raise boost to 10psi (not sure what the stock turbo can do on those), and get some form of piggyback ecu (speak to a good workshop about recommendations - many of us use the apexi SAFC for air/fuel tuning and the SITC for ignition timing but these are fairly simple devices. great for if you just want an extra 30-50kw but any more than that and you'd be better off looking for a more capable ecu).

To improve shift quality and speed, look for a "shift kit" for your auto trans. I'm not sure if these are available for the M35 but you can always speak to some professionals and I'm sure they could provide you with the info you're after.

Hopefully this info has been helpful to you

As for justifying all of this to the wife...I wish you luck (speaking from experience. I tend to bargain with my wife, ie. she gets clothes, I get car mods)

Oh and my S2 with 160awkw definitely has the throw back in the seat feeling. It will never be as much as with a lighter car and often doesn't feel like you're doing the speed you're doing, but lets say when I bought mine it didn't feel like it had a turbo, and now its very obvious. Love the sound too!!

Edited January 19, 2008 by pixel8r

[Jetwreck]

Yeh found out about that filter box bit....This is the quote from a V35 guy "If you get the part no from Nissan FAST software I think you can order it through your local Nissan dealer, all they need is the part number. I think...."....I just need to find a PC and download FAST now....doesn't work on a MAC and there all we have in the house and at work.

The rest of the info is here http://www.skylinesaustralia.com/forums/Ni...l=FAST+download

P.S. You have the same problem as me with Auto's....I don't believe I have ever owned one...wish these cars came in manual in 2002-2003

Edited January 19, 2008 by Jetwreck

[andy65b]

sent PM about FAST. got it but will not open yet!

[Jetwreck]

Just puchased the turbotech boost controller on Ebay....also just got back and now installing a boost gauge....hopefully I get it all installed before the finds out wife finds out.....I'll let you know the results....starting with what the standard boost is on these fat cows.

P.S. One more thing to do before I start....Beer run!!!

[Jetwreck]

F$#^%^&%$^K...I just spent the last 20 minute typing up a response and my computer locked up...lost it all...was neally as long as pixel8r's.

Anyway...I'll shorten it for you...I have the result's of the standard boost for these fat cow's but before I give them to you you will have to read my beer influenced drivel.

1. I hate mounting gauge's

2. Can anyone tell me why the mounting pod's are more expensive than the gauges!!!!...the poor guy at Auto One or wherever it was couldn't give me the answer.

3. I hate rechecking stuff because the result does not seem correct.

4. I ran out of beer...just sent the wife out to get some more....finally she does something useful. P.S. And yes lucky she never get's on the SAU thread.

5. I hate rain...just finished washing the car.

Anyway I think I have made my pointless so onto the result's. Unless I am mistaken the M35 turbo is the same ceramic setup as the previous RB25's which are only good for about 14-15PSI before they spit the impeller through the exhaust(Correct me if I'm wrong). Therefore I think we need to get a bit more info on the M35 turbo's as it's standard boost is....14-15PSI....not only that once the lag has gone it spin's up bloody quick. Bit depressing for me as I don't know were to go from here in terms of performance. I hope I have put the gauge in correctly(see pic below...it's the clear line).

[andy65b]

I will be interesting to hear how the boost pressure goes with the Turbotech booster!

I think you are right about the same turbo But I can't find any info on what boost pressure it will take before it spits the dummy.

I took the cover off the airbox and fitted some flyscreen to see what difference it made. Sounded about the same but maybe a little more throaty under hard acceleration. No real difference at the bottom end (maybe even a bit flatter) but felt better at the high revs where before it had run out of puf. see pic below.

I got the FAST up and running but you would not believe it! The M35 is not covered! The V35 is covered but I have been unable to find adigram showing that fitting. It may be a case of fabricating my own version.

[andy65b]

F$#^%^&%$^K...I just spent the last 20 minute typing up a response and my computer locked up...lost it all...was neally as long as pixel8r's.

Anyway...I'll shorten it for you...I have the result's of the standard boost for these fat cow's but before I give them to you you will have to read my beer influenced drivel.

1. I hate mounting gauge's

2. Can anyone tell me why the mounting pod's are more expensive than the gauges!!!!...the poor guy at Auto One or wherever it was couldn't give me the answer.

3. I hate rechecking stuff because the result does not seem correct.

4. I ran out of beer...just sent the wife out to get some more....finally she does something useful. P.S. And yes lucky she never get's on the SAU thread.

5. I hate rain...just finished washing the car.

Anyway I think I have made my pointless so onto the result's. Unless I am mistaken the M35 turbo is the same ceramic setup as the previous RB25's which are only good for about 14-15PSI before they spit the impeller through the exhaust(Correct me if I'm wrong). Therefore I think we need to get a bit more info on the M35 turbo's as it's standard boost is....14-15PSI....not only that once the lag has gone it spin's up bloody quick. Bit depressing for me as I don't know were to go from here in terms of performance. I hope I have put the gauge in correctly(see pic below...it's the clear line).

Hi Jetwreck

How has that boost gauge that you installed been going? Are you still looking at 14-15PSI as the standart boost?

Did you install the Turbotech yet? IF so did it yeild any good results?

Cheers

Andy

[Tangles]

well, the EVO you have most likely utilises the anti-lag system (im sure evo's do, probably wrong tho), hence why your evo spools so much faster than the M35. also, the evo is 1bar psi and the stagea is half that?

You'll need full intake and exhaust mods, ie free flowing air intake, and free flowing exhaust

Bump up the boost to 12psi

Arrange a SITC (apexi super ignition timing controller) as once dialed in on a dyno you can bring back the spool time by a few hundred rpm.

A ball bearing high flow turbo will spool a few hundred rpm quicker again than a bush bearing high flow turbo

Get the MV Automatics shift kit for the auto, well worth it.

Once you do the shift kit, exhaust, intake mods, safc + sitc, larger turbo, better do the fuel pump too.............

Gets fun and expensive the further you delve into it

[Jetwreck]

Hi Jetwreck

How has that boost gauge that you installed been going? Are you still looking at 14-15PSI as the standart boost?

Did you install the Turbotech yet? IF so did it yeild any good results?

Cheers

Andy

Hi Andy,

Put the boost gauge on and it's already 14-15PSI without doing anything. My car goes to Hornsby Nissan in the next week or so for a front end noise in the driveline so I'll get them to check wether my boost gauge is correct or wether the car already has some sort of mod I don't know about. Not going to install the Turbotech until I can confirm boost.

[mxfly]

Hi Andy,

Put the boost gauge on and it's already 14-15PSI without doing anything. My car goes to Hornsby Nissan in the next week or so for a front end noise in the driveline so I'll get them to check wether my boost gauge is correct or wether the car already has some sort of mod I don't know about. Not going to install the Turbotech until I can confirm boost.

Im quite surprised it's 1 bar of boost already stock, if your gauge is reading right. That doesnt make much room for more boost then.

[mxfly]

Just found out through the Fujitsubo website that after putting their Legalis-R cat-back on, the boost went up to 1.09 bar.

[Jetwreck]

Just found out through the Fujitsubo website that after putting their Legalis-R cat-back on, the boost went up to 1.09 bar.

Hmmmm.....without touching anything except the exhaust? If so that explains my boost getting up to 16psi sometimes and then flattening out to 14psi.

[mxfly]

Hmmmm.....without touching anything except the exhaust? If so that explains my boost getting up to 16psi sometimes and then flattening out to 14psi.

That's right. They only changed the cat-back section. So the dump and front pipes were stock units. So changing the dump and front pipes could yield even more boost, which could be potentially dangerous for a ceramic turbine.

Edited February 18, 2008 by mxfly

[AlexCim]

(I am talking from a Series 1 Stagea perspective)

You can't compare a Stagea to an Evo.

I just went Stagea -> Evo IX and there was a reason to do it.

The Evo is a rally car, the Stagea is a GT car. It can be fast, handle well, but it will never be as good as an Evo. The response on the Evo is amazing compared to the Stagea, thats just the 4G63 and turbo set up. RB's are naturally laggy, the M35 motors are probably very similar to that.

You will eventually learn that the Stagea is a family car and is no Evo. The only things I can recommend to do you is, more boost, more flow (air filter, GOOD intercooler, exhaust) and shift kit auto. Thats all

[Jetwreck]

That's right. They only changed the cat-back section. So the dump and front pipes were stock units. So changing the dump and front pipes could yield even more boost, which could be potentially dangerous for a ceramic turbine.

That's sux...what am I going to do with the boost controller then!!!...lol.

P.S. How sure are u that it is ceramic turbo? I have my doubts!...will let you know soon though as I am pulling it out to get high flowed and steel impellers(I think). New dump pipe and new high flow cat is also going in.

Edited February 18, 2008 by Jetwreck