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My brothers 1st gen mx6 pulls harder than my gtst please help!!!

4bella

By 4bella,
in Engines & Forced Induction

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4bella Collaborator

4bella

Posted
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just wondering is it normal for an r32 gtst to be slow in low revs? or should i get my car tuned? I have a mines computer and a gt28 turbo, 3 inch piping boost control, high boost set to 18-20 psi, air filter pod , fuel regulator and my brothers mx6 turbo beats me 0-100km/h how embarrasing....with the mods i have i would of thought i would have at least 150 kwrw and just whip my brothers mx6....please help....!!!

Revhead Grand Master

Revhead

Posted
Posted

Slow revs, or slow speed? RB20's won't have anywhere near the low-end torque of the F2T in the MX6, but should kill it in the top end. In other words, unless you have problems or his is modded, under 30-40km/h rollons he will beat you, but after that, he sees tail lights :)

Put it on a dyno and have your AFR's checked. It's possible that the Mines computer was tuned for a completely different car (different turbo, cams, compression, capacity, god who knows), which would explain less than optimal performance.

How is it in the higher gears?

gtir_94 Contributor

gtir_94

Posted
Posted

You say you have 3in exhaust? Does that include your dump-pipe also? If not, you can find quite nice low-end gains by getting your dump done, as most cast dumps are quite restrictive.

What GT28 do you have? 300, 350, 400 440hp? if you have the a higher hp rated one you wont get that low-end grunt.

From what I understand the Mine's computers are tuned for Japanese conditions NOT Aussie conditions, ie japanese fuelling [higher RON], Aussie weather is hotter than Jap, therefore, less dense air, so it all maybe out of whack.

Have you and your bro swapped cars and seen if its not the driver [ie, you] holding your cars potential back. If your bro gets the same result as you in your car and visa versa, then you can definately blame the car :)

Also, not knowing the wieght of the MX6, maybe its lighter than your car, and can get off the mark easier. As revhead mentioned your car should get there in the end.

bbenny Mentor

bbenny

Posted
Posted

my mate has a modded MX6 and i would whip him at every traffic light drag when my R32 was stock, you should be beating him, but as others suggest we need more specific turbo specs and a/f ratios make a difference.

now that my car has a fair few mods, it is defenantly slower in very low rpm, but from 3500rpm there is no way the MX6 can touch it.

are you launching properly, cause if you have a pretty big turbo and are bogging down it will take for ever to catch up...

bbenny Mentor

bbenny

Posted
Posted

have to agree with GTST there!

but honestly something must be seriously wrong if you cant beat a freaking MX6 with your list of mods. get in on the dyno and check it out.

you might find that you only need to spend $250 on a remapped chip and make an extra 50rwhp like i did.

good luck mate!

4bella Collaborator

4bella

Posted
  • Author
Posted

Hey guys thanks for the feedback....yeah on low boost my boost is on like 10psi-12 it keeps changing but yeah on the end of 2nd gear i catch up to my brothers mx6 ...its just seems a bit sluggish off the mark...well the mx6 was my car previously so it aint the driver...my car has a dump pioe, it has the full exhaust from turbo to the back ... as with my car i only bought it 2 weeks ago with all these mods on it already so thats why i dont know much about the r32 gtst... i just knew the power rating on it was alot bigger than an mx6 so i was worried why it was so slow on low revs and off the mark...once i flick the high boost the car kicks arse but yeah sometimes the boost cuts off. i know i have to dyno tune the car as i was told becasue it has a mines computer. just thought id get some info before i do just in case...

with the size of my gt 28 turbo i dont know the exact size as yeah i bought it off a dealer just 2 weeks ago and i dont know how to check what size gt 28 it is... with the a/f rating i have a guage in my car but it runs crazy and all over the place like when the car is idling the a/f ration reads at high rich sometimes and then on low revs its on stoich(mid level) but yeah when i really give it its on very rich again.....but sometimes when the car jerks around when im climbing the revs it goes all over the place....

you guys know of any places to dyno tune my car?

how much do u think it will cost?

i dont know much about this tuning stuff so what is involved in this whole tun process?

many thanks guys for the input.......

TTT Grand Master

TTT

Posted
Posted

First things first..

1.) The Mines ECU.. get rid of it.. send a PM to a guy on these forums called TOSHI and speak to him about doing a remapped ECU for you for the mods you have...

check this link for his previous posts...

http://www.skylinesaustralia.com/forums/sh...ht=remapped+ecu

2.) You say you have a GT28 but then say it is from a dealer and you are not sure how to tell..

Are you sure it is a GT28?

On the turbo, does it say NISSAN or 16V anywhere? you should be able to see it from the engine bay.. if it does, then that is a stock turbo... but then again 18psi you sometimes push through it would pretty much destroy a stock one..

3.) you have a fuel regulator but no aftermarket fuel pump...

running that sort of boost would surely not last on a stock fuel pump.

4.) you have not mentioned anything about an aftermarket intercooler...

are you still using the stock side mounted one on the R32?

My suggestion would be as follows..

1.) go and do a simple dyno run so that you can get a current power figure on low and hi boost settings.

you can also see what fuel mixtures you have as that gauge you are talking about doesn't show shit as you probably have a stock O2 sensor.

From this, you will be able to tell where you are going wrong.. if anything is wrong..

2.) THEN, I would do this..

Front mounted intercooler

Fuel pump

Then ECU from Toshi.... He's a top bloke..

Im sure that if you have a GT28 and all the other mods and at 18psi with good A:F mixtures, you should have about 180rwkw or possibly more..

and the costs??

dyno run - $80 (or cheaper on club dyno days)

FMIC - $1000 (including piping and so on - or cheaper.. there are 2 GTR coolers for sale on these forums for $350 each...)

Fuel pump - $200 (WALBRO 255L pump from internet shops... try www.mercurymotorsport.com.au )

Remapped ECU - $300 from Toshi.. and he will go to a dyno with you to make sure it is spot on and try different chips/ecu's to get the perfect one)

basically under $2000...

LOW25T Enthusiast

LOW25T

Posted
Posted

yeah dude, those cars arnt much quicker than a commodore/falcon, that suxs dude....

Hey Bbenny, I remember that MX6! are u talking about when u used to race franks in his MX6 when we went cruisin occasionally? i was the one with the grey falcon...

4bella Collaborator

4bella

Posted
  • Author
Posted

as i said i was just wondering why my car takes a while to boost up coz off the start my bros mx6 is already ahead by a car length and a bit but once i hit 2nd gear i catch up to him and pass him and thats on stock boost....i was just wondering why it was so sluggish off the start...and yeah when i give it it sometimes jerks while boosting up...also once i flick the boost switch a huge black pile of smoke comes out and after the exhaust is full of fumes...i was told it was the mines computer as it runs rich fuel and the a/f ration is off...so yeah off to the dyno, so is it a must to change the mines computer? or can that e re-tuned?

with my turbo it definately aint the stock one ...i can see the writing on it saying "GARRETT" and is bigger size than the stock ones....and yeah i have no front mount intercooler....

well at the moment im on a bit of a tight budget as yeah i have just only bought the car.... so what do u think i can do for the meantime? can the mines computer be re-mapped at all so it will fix the a/f ratio and the idling problems?

my friend owns a my01 wrx and he got an apexi computer which handles boost, a/f ratio and sits in his car ...will that help at all?

TTT Grand Master

TTT

Posted
Posted

the mines ECU can only be tuned by MINES and there are no places in aus.

However, someone MIGHT be able to get rid of the mines chip and make a new one for you for our fuel with better a:f ratios.

all that boost through the stock R32 intercooler is a big ask.

you're going to break something.

keep the boost down or get a decent fmic.

you might be on a tight budget but look at it this way.

$1000 for a cooler now or over $4000 for a decent rebuild when your engine dies from detonation.

the apexi computer in your friends car that handles boost and a:f ratios is probably a Power FC.

NO you can't take itout of his and put it in yours.

there are ones for the R32 GTST's but are pretty rare from what I remember. and not cheap.

as for the MX6 being quick off the line..

what did you expect..

2.2L, 4 cylinder with a rather small turbo.

they get about 5psi boost from just under 2000rpm all the way to about 5000rpm and then die off towards there red line of 6000rpm.

of course it's going to be quicker off the mark than your 2L 6 cylinder with a larger than stock turbo.

The MX6 is not what I would call fast, but they are pretty torquey (if that is a word) around town due to there smallish turbo and 2.2 capacity.

JAM*353 Apprentice

JAM*353

Posted
Posted

is anyone reading what hes saying, altho not clear, he's just saying he's behind in first gear, then in second he is ahead of his bro's MX6!

If anything, you need to look at your launch, and i would go as far as saying that is your problem, as you say in second your fine, which in theory you should have full traction and be on your way!

As well as that you need to understand the limitations and workings of your car, if the new turbo you bought is bigger than standered, the time it takes to spool is obviously going to be longer!!

Take notice of peoples opinion of the Mines computer its no good in the long run, and in future i would recommend you actually take notice of what parts your buying and what neeeds to be done to the car in order to make them work properly!

ie- a bigger turbo, with no FMIC and no dyno tuning after adding many go fast bits! :Bang:

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