upping boost slightly

Discussion and technical advice the SW20 MR2. 3S-GTE, 3S-GE, 3S-FE etc
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Dan23
Posts: 250
Joined: Tue Jun 30, 2009 2:38 pm
Location: Orpington

upping boost slightly

Post by Dan23 »

right im thinking of getting a boost controller, whether it be manual or electronic, im unsure of yet, depends what my budget will go to. but basicallu im thinking of taking the car up to 1bar, im sure iv heard people say the stock turbo (import) will bo ok at that. iv got a few little mods to go along with what i would consider stage 1 mods, so filter/exhaust system/de cat. but i wanna know is it worth me getting a better IC? iv seen this on ebay http://www.ebay.co.uk/itm/400212629887? ... 1423.l2649 which doesnt seem to be to badly prices seeing as it comes with the pipe work too, but am i just wasting my money getting it? im not looking for big power out of my mr2 as i still want it to be a pretty reliable daily driver, just want it up to around the 250-260bhp mark
Nails
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Re: upping boost slightly

Post by Nails »

the 1bar is max for a rev 2, had mine running around 13psi and it felt pretty good.

also had one of those toyo sports intercoolers and it seemed to work fine, Ive since got another one of them for my rev3 but its not from toyo sports and the pipe work fits really pap, had to mess around with them and cut one of them down and it still doesnt fit very good, so buy the toyo sports one
Dan23
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Re: upping boost slightly

Post by Dan23 »

So worth getting one even tho I don't want massive power yeah?
djpkins
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Re: upping boost slightly

Post by djpkins »

essential matey...or you will compromise the cars ability to perform as you want it to when upping the boost...efficiency is of paramount importance if you want it to be safe.
With a free flowing exhaust, air filter and 1bar of boost...you could add another 30bhp from stock...don't be tempted to cheap out...it's important that you monitor the boost levels accurately.
eg- my avcr is set at 1.25bar high boost...I've seen it spike at 1.49bar!!! when the weather conditions were right and I was banging it a bit too hard chasing a much more powerfull car....my point being that not only will you gain a bit more power on a cool crisp evening, you can also drive harder than your usuall style when on the ragged edge...if your already pushing the power levels a bit by adding too much boost...POP!

lol...believe me, once you get a taste for a bit of power...it's all over man...you will deffo want more.
Consider the rev 3 conversion...you'll need.
rev3 ecu...£50.
Map sensor...£50ish.
AIT sensor...£15
rev3 lambda...£50.

This could be done for the price of an electronic boost controller...and still get a better IC as you've already planned...the car will be more efficient, powerfull and a better base to work from, another score would buy you a manual boost controller...to up it a wee bit more as the hunger takes over. :thumleft:
Dan23
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Location: Orpington

Re: upping boost slightly

Post by Dan23 »

iv been there done it and got the massive bills to prove it for pushing cars to an inch of their life, my s13 was stage 3 running hybrid turbo, wisco pistons, bored out chamber, the works, running well over 300bhp and i could waste £10 of fuel in under 10 miles in it lol but it wasnt a very reliable or daily drive, my mr2 has to not only be a toy but get me to work every day etc, so i hae to keep that line between going stupid with it and keeping it reliable, this is why im not after big power, just a bit more, would be nice to have it on par if not slightly faster than a GT4 (so around the 250-260 mark)
Nails
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Re: upping boost slightly

Post by Nails »

my rev 2 had a rsr exhaust on it, el cheapo ebay decat pipe, induction kits of some sorts, and a toyo sports intercooler, with the exhaust being so free flowing it ran a smidgen under 13psi without a mbc, used it as a daily driver for a year and it was fine ran perfect apart from some crap ht leads which was easily solved.
Only thing I was going to was to disable the tvis and fit a mbc as 1st and 2nd werent as interesting compared to 3rd/4th unrestricted but never got round to it.
mr2's seem to give decent gains with cheap-ish mods.
Dan23
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Re: upping boost slightly

Post by Dan23 »

whats all this disable the tvis about exactly?
Nails
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Re: upping boost slightly

Post by Nails »

it reduces boost in first and second gear, around 8psi.
Harold
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Re: upping boost slightly

Post by Harold »

Is there a particular reason boost is limited in 1st and 2nd?
Dan23
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Re: upping boost slightly

Post by Dan23 »

So removing it delimits boost in 1st and 2nd? I assume it's there as a safety thing, the japs bring over protective, probably down to people who don't let them warm up before thrashing the engine in 1st and 2nd. Am I on the right page?
GBTurbo
Posts: 138
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Location: Hants. 1995 Rev 3 Turbo

Re: upping boost slightly

Post by GBTurbo »

I had an old Rover 620 turbo which had a similar thing to the TVIS. If I remember, it limits the boost in the lower gears (1st-2nd) to preserve the gearbox and other components, clutch etc.

I imagine its a similar thing for the mr2.

Mines disabled anyway :D
raptor95GTS
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Re: upping boost slightly

Post by raptor95GTS »

tvis changes the volume of the intake chamber, tvsv is what limits the boost in 1st and 2nd (also allows the ECU to stick the car into safe mode in all gears) The reason it's limited is for a bit of a safety margin in the lowest gears. Removing it makes first and second pretty intersting to say the least. On my rev3 I disabled it and fitted the MBC to run 16psi. First time I came out of a 30 zone I dropped to 2nd and floored it and bloody hell it was quick, really quick lol. It gets addictive :twisted:
Dan23
Posts: 250
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Re: upping boost slightly

Post by Dan23 »

How do you disable it? Or have a link with a how to, on my phone so searching is a bit of a sod lol
cvega666
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Re: upping boost slightly

Post by cvega666 »

djpkins wrote:
Consider the rev 3 conversion...you'll need.
rev3 ecu...£50.
Map sensor...£50ish.
AIT sensor...£15
rev3 lambda...£50.


And a steel head gasket... upping boost with a rev3 conversion on a paper gasket will result in a failure eventually...
Current: 2007 Porsche Cayman S
Gone: '94 rev3 NA, '92 rev2 Turbo forged, '07 Civic Type-R
raptor95GTS
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Re: upping boost slightly

Post by raptor95GTS »

Dan23 wrote:How do you disable it? Or have a link with a how to, on my phone so searching is a bit of a sod lol

the electrical connector is on the inlet of no4 running which you access from under the car, Easy peasy and no cutting pipes
Marf
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Location: West Sussex

Re: upping boost slightly

Post by Marf »

allan welsh wrote:
Dan23 wrote:How do you disable it? Or have a link with a how to, on my phone so searching is a bit of a sod lol

the electrical connector is on the inlet of no4 running which you access from under the car, Easy peasy and no cutting pipes


+1

Just unplug it
Phill P
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Re: upping boost slightly

Post by Phill P »

Mines a rev2 with similar mods,did have an mbc and went over to a gizzmo ibc,and you can adjust the way the turbo spools up with the ibc (I think I explained that correctly). With an MBC you can't although I can now see very exactly what it boosts to and how much a cool day still will cause it overboost.

Mines running .9 to .95 bar and still unsure about a new IC,toyota did design it to run .9 on a rev 3 so I'm still unsure why I really need it if thats all want to run.

If I did the headgasket then I could see the point as I could up it a little further.

:thumleft:
Rota torque drifts Japseed exhaust Apexi air filter Gizzmo ibc Apex springs Hks turbo timer 242bhp at .8 bar
smartdj
Posts: 165
Joined: Thu Mar 17, 2011 2:45 pm

Re: upping boost slightly

Post by smartdj »

Nails wrote: so buy the toyo sports one


toyosport intercooler, what a piece of cheap crap if iv ever seen it.

fitment, crap
pipe work, cheap crap
intercooler, i had better performance from my stock cooler! fact

i had one on for about 2 weeks, then becuase it was so terrible i went and spent the money on a product which works (rogue chargecooler)
Marf
Posts: 6728
Joined: Tue Jan 17, 2006 4:56 pm
Location: West Sussex

Re: upping boost slightly

Post by Marf »

Phill P wrote:
Mines running .9 to .95 bar and still unsure about a new IC,toyota did design it to run .9 on a rev 3 so I'm still unsure why I really need it if thats all want to run.


Because the stock IC is crap. On a mildly warm day the ECU will pull back boost as the IC cannot shift enough heat to run 0.9 bar all the time. :)

To put it in context, I had a string of Charade Turbos. 993cc Turbocharged making 100hp standard. The stock MR2 Turbo IC is identically constructed, but about 1" taller.

The daihatsu IC had problems keeping 150hp of charge cool. :eye:
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