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arjunior45
02-08-06, 10:44
Does anyone knows how much is the max boost {in bars} that a Q4 can handle
a} with catalytic converters
and
b} without {removed} them
or
c} with Gr.A {free flow type} one?

I'm thinking for a Integrale 16V "trackday" type map {1.6 - 1.7 bar boost} or for a "1.5 bar costant boost" map. Any comments?

Cheers

Nick

Juan AR155Q4
02-08-06, 13:01
I used to have 1.7 bar of boost pressure. DidnŽt want that pressure, just a broken wastegate actuator. This issue + a broken knock sensor cost me a melted piston. :oops:
I was without catalytic converters, and the head gasket wasnŽt even the original Q4Žs, just the one as the Fiat Tipo. It wasnŽt blown, but was near to.
Actually IŽm running 1.3 bar but not surely is this is the max pressure cause IŽm with an engine with 3000km and I donŽt floor it yet.

What about cooling the air instead of increasing pressure? Water-cooler? FMIC?

arjunior45
02-08-06, 13:40
Sorry to hear about the piston.
I'm going to use Gr.A head gasket, Gr.A head bolts and forget pistons {with CR at 8.5:1} as soon as possible. So, it will be nice to know the max boost - even with a "broken wastegate actuator and a broken knock"!

Did you have this 1.7 bar with the original Q4's Garrett turbo?

Cheers

Nick

MaxiBoost
02-08-06, 14:20
if you trust yourself and car you can boost 2 bar ,ofcourse your turbo handle .

But ,original Q4 map sensor is 2.5 bar type ,
I mean map sensor and ecu sens maximum 2.5 bar boost pressure .
(atmosphere pressure is 1 bar and if you can boost +1.5 bar ,finally 2.5 bar )
So ,if your head gasket and pistons original never use up 1.2 bar.

Juan AR155Q4
02-08-06, 14:51
Sorry to hear about the piston.
I'm going to use Gr.A head gasket, Gr.A head bolts and forget pistons {with CR at 8.5:1} as soon as possible. So, it will be nice to know the max boost - even with a "broken wastegate actuator and a broken knock"!

Did you have this 1.7 bar with the original Q4's Garrett turbo?

Cheers

Nick

My compressor side is a T4 0.50, the turbine side is the std one.

You are increassing CR and boost, what are you going to do to prevent detonation? Waterspray only wonŽt be enough.

arjunior45
02-08-06, 18:54
@Hakkan,
thanks for the info. If I understood well, the original turbine can give up to 2 bar boost. Am I correct?

@Juan,
I'm going to rise the CR up to 8.5:1 but I'm not that sure that I'll rise the boost pressure up to 1.7 bar. I think it will be suffient for me to have costant boost at 1.4-1.5 bar.
Any way, do you have any suggestions concerning the detonation's prevention? Do you think that I must have some kind of prevention even with less boost {1.4-1.5 bar}?

Cheers

Nick

MaxiBoost
03-08-06, 09:23
@Hakkan,
thanks for the info. If I understood well, the original turbine can give up to 2 bar boost. Am I correct?

Nick

No ,I dont know original turbo create how much boost ,Im give only example .
Im use my turbo 1.4 bar boost ,its t4 compressor ,original t3 turbine .

When use Q4 with 1.7 bar boost ,you need very strong parts (forged pistons,steel gasket etc , water/alcohol injection maybe bigger injectors , egt ,wide band lambda and change ecu with programmed type ) otherwise its very risky .

arjunior45
03-08-06, 10:27
When use Q4 with 1.7 bar boost ,you need very strong parts (forged pistons,steel gasket etc , water/alcohol injection maybe bigger injectors , egt ,wide band lambda and change ecu with programmed type ) otherwise its very risky .

I will not rise {at the moment} the boost up to 1.7 bar but it will be nice to have a "trackday" like map in a 4-map eprom switch, just in case!
This Q4 will an everyday car but I'd like to see how this car can go in a short circuit lap.
Any way, do you think it will be also very riscky to have 1.35-1.4 bar boost without forget pistons and water/alcohol injection?

What is this "egt" you've mentioned?

Cheers

Nick

Jarkko
03-08-06, 12:19
I have in my car standard headgasket and 1.4-1.45 bar boost ( not just peak boost ) and no broplems ! with original t-3 turbo it wont help to get any more power if you use over 1.2bar boost, but you get more torque still.. if you are using about 1.5 bar boost with original turbo, it wont last long. and yes the map sensor is 2.5bar, but theres also (at least in squadra chip ) set to max boost / rpm, so you cant use 1.5 bar if you dont mod. the chip :wink: and ... take your cars to dyno, to see the engine wont go too lean!!! if you have good mixture, theres no broplems! but with small turbo, and original cooler etc etc... I would not use more than 1.3 peak and 1.2 hold boost

Juan AR155Q4
03-08-06, 13:02
@Hakkan,
thanks for the info. If I understood well, the original turbine can give up to 2 bar boost. Am I correct?

Nick
When use Q4 with 1.7 bar boost ,you need very strong parts (forged pistons,steel gasket etc , water/alcohol injection maybe bigger injectors , egt ,wide band lambda and change ecu with programmed type ) otherwise its very risky .

Be sure on that, I melted the piston (a broken knock sensor too).

EGT-> Exhaust Gas Temperature

Take a look here: Zeitronix (http://www.zeitronix.com/Products/zt2/zt2.htm). This is a wideband with EGT and a couple of channels for logging.

MaxiBoost
03-08-06, 16:04
Yes ,egt is very imported ,

http://www.streetrodstuff.com/Articles/Engine/Detonation/


this is my egt probe

http://img49.imageshack.us/img49/6241/1jm8.jpg

arjunior45
04-08-06, 17:44
Thanks a lot guys.

I've already had made my own "turbo timer" with incorporated "wide band" oxygen sensor, boost meter, turbine temperature meter, air-intake {induction} temperature meter and differential temperature meter. I'm going to test all the mods in Q4 with this device.

What I would like to know is the maximum boost that I can take {remaping the IAW} using the original turbine {with or without cats}.

As I have understood so far, by using the original turbine {T3} and the original MAP sensor, it is possible to rise the boost up to 1.5 bar (which is the max), with some risk.
Am I correct?

What about if I keep the original turbine and change the MAP sensor using maybe the one from Integrale 16V-EVO1? Remaping the IAW will it be possible to reach the 1.7 bar?
I already know that there is a need for forget pistons, Gr.A headgasket a.o. for such a high boost.

Cheers

Nick

Juan AR155Q4
04-08-06, 20:40
I've already had made my own "turbo timer" with incorporated "wide band" oxygen sensor, boost meter, turbine temperature meter, air-intake {induction} temperature meter and differential temperature meter. I'm going to test all the mods in Q4 with this device.


:shock:
I want one!!! Price it!!!

About the max boost, surely youŽll have to change your map sensor, otherwise, ECU wonŽt "see" pressure higher than 1.5 bar. And of course youŽll have modify your mapping.

Jarkko
04-08-06, 21:54
why do you want to blow your turbo ? if you use that 1.7bar, the turbo wont last long ! but if you modify your turbo... it will last 1.7bar. what I mean is that if you really want to use high boost, be sure the turbo is good for that. :wink:

arjunior45
04-08-06, 22:32
@ Juan
as soon as I'll find the link to this device - it is Do It Yourself - I'll post it here. Unfortunately, for the next few mounths I won't have that free time to make the pcb for it and all the rest.
This is the link for the timer: http://homepages.picknowl.com.au/pkl/turbotimer/picproject1.html
I've just combined a wide band oxygen sensor to its panel.

@ Jarkko.
So, you think that the T3 will not last long at 1.7 bar! Then, which turbine would you suggest to me in order to a peak at 1.7 bar? The one from EVO1 or 16V?

P.S.
Probably {99%} I won't go for 1.7 bar boost. Though I'd like very much to see how this car can go in a short lap with such a boost. I have also an Abarth 16V 1.7 bar boost map and I'd like to try to convert it into a Q4 like map.

Jarkko
07-08-06, 18:20
hmm my english is bad, but the turbo must be build for high boost use. for example my new gt is good for near 2bar use. it has 360 ( dont now the word ) and T-3 has original 270. at least but those and check the turbo.. and again its good for only about 250-260hp at max ( T-3 ) so use bigger turbo 8)