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Location:
Canberra
Registered:
March 2004
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Forged pistons
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Fri, 05 March 2004 02:13
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Does anyone know where i can get my pistons forged for a little less in Canberra??
Can't run my boost as high as i would like 
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Registered:
May 2002
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Re: Forged pistons
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Fri, 05 March 2004 05:30
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Hi MR2 3SGTE,
I am assuming you mean you want to buy forged pistons, not forge the ones you have got?? (just the post implies you want to forge what you have got  ). I think you will find the best price on forgies will be interstate, a few places advertise on the net. A search will bring them up.
The pistons in your car now won't be inhibiting the amount of boost you can run, although forged pistons will tolerate detonation more than standard cast pistons if you plan to just wind up the boost and let the air fuel ratios go out the window?. BUT I am assuming you are not planning to drive around pinging/detonating anyway.
There are a number of internally stock 3SGTE engines and others without forged pistons running over 20psi. I was at a local Dyno day 2 weeks ago where a 1JZGTE Soarer was running 28psi and has been doing so everyday for over a year without problems (internally stock, aftermarket ECU).
The key to running high or higher boost lies in the tune, good air fuel ratios will be kind enough on your pistons and head gasket to allow the boost you want to run. Even if you get forged piston to "toughen" it up a little in the event of a little bit of detonation, it will still only allow you to run the same boost you could have with standard pistons. The forged pistons will allow you to push the limits of tuning a little more (a ping here or there won't kill the forged pistons, most cast pistons can take a ping or two as well).
I am no expert on this and I don't know what other mods your 3S has but I am pretty sure pistons aren't restricting your boost (unless we are talking 25+psi and on the knife edge of leaning out and you want a bit of reassurance when it does detonate).
Cheers,
Shane.
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Location:
Canberra
Registered:
March 2004
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Re: Forged pistons
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Fri, 05 March 2004 08:37
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Hi Shane,
Thanks for the info.
Re-reading my post your right it does sound like i wanted to get the old ones forged.
I went to a mechanic that has done heaps of work on performance cars and he asked what i wanted several things for and when i told him he said are you running stock pistons to my obvious reply of yes he imediately said not to run boost with the 3SGTE over 14PSI as he has seen at least 3 that have blown the pistons.
I ahve also been told by a fair few people that the 3 SGTE is only capable of running 9-10PSI safely, and i know this is a load since i have been running 14 for some time, however i am going to have to buy a new electronic boost cintrol as my manual one peaks and falls back to 10.
where abouts are you?? supose i could just import the pistons if possible.
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Registered:
May 2002
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Re: Forged pistons
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Fri, 05 March 2004 12:01
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Hi,
It sounds to me like the mechanic is referring to the 3TGTE not your 3SGTE when he says keep the boost low, and the pistons will split at boost around 14psi etc (easy and common mistake to confuse different engine families in the Toyota range). This is a well known problem with the 3TGTE when people up the boost on stock injectors and ECU, there is plenty on the net to back this up (and is exactly what it sounds like the mechanic was talking about). The thing to remember is that its not the boost that will kill the pistons it's the lean air fuel ratios and associated detonation that will damage them if poorly tuned.
The 3SGTE is well and truly safe as can be up to 18psi as long as air fuel ratios are kept in order. The group A celica GT4's are mapped up to 17 or 18psi, and we all know that most of the time Toyota likes to over engineer a little too, so with after market or programmable ECU's they can be tuned to higher boost than that and have no problems at all.
There are a few guys on these forums that are running in excess of 20psi without problem on stock internals. I think there is a guy in the Celica club here in Canberra that has a well setup 3SGTE in a GT4 celica and it runs more than standard boost, he may be a good person to talk to locally regarding mods to the 3SGTE. One of the other Celica Club members may know how to contact him.
If you really want to talk to some people in Canberra that know the limits of the 3SGTE then head out to Neal Bates Automotive in Hume, they have had way more experience with this engine than most (they have had them in GT4's MR2's and the Corolla's they have at the moment).
I am interested in your boost control problem too, I was having a similar issue where my boost would spike and then drop down to levels well below what I wanted it set at (turbosmart manual boost controller). I was spiking to 20psi and dropping down to 13 or 14 psi. I tried a number of things to fix the problem and it is sorted now and will hold up to 19psi without spiking. I would do some investigation into the problem just in case you get your electronic controller and it doesn't fix the problem or only masks it (but the electronic controller would be cool, I would like one myself). The manual controller should be able to cope with 14 psi as the preset boost with no problems.
By all means get the forgies if you want them, but you have got a great toyota engine in your car that you can take a lot further before you really need them.
I am in Belconnen and was keen for a cruise to meet up with you new people tonight (friday) but I got home and saw no one had organised any meeting time or place. Oh well another time will be fine.
Cheers,
Shane.
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Location:
Canberra
Registered:
March 2004
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Re: Forged pistons
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Fri, 05 March 2004 12:11
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Yeah was pretty keen myself for a bit of a cruise, maybe a garage day would be cool to.
Thanks for your input as finding any decent mech's in canberra is so hard for imports, I have thought about going down to neil and having a chat with him.
So how did you fix your spiking problem??
I was thinking about an AVC-R apexi boost controller they just look so cool plus can chang boost levels alot easier.
another question i got a quote from J-Racing for a new paint job wich included a pearl over lay just re spraying no panel damage for $2800 $3K this is by far the cheapest quote i have had but if anybody knows of a cheaper price for a decent job i am very interested.
Cheers guys.
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Registered:
May 2002
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Re: Forged pistons
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Fri, 05 March 2004 12:34
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Hi,
I fixed my spiking problem by:
*making the line to the wastegate actuator as short as possible and positioning the boost controller as close to the actuator as possible
*I also found that the "gate" in the boost controller didn't open until 18psi!!, so I modified the gate to open at 10psi (as that will soon be my minimum boost setting once I fit the in-cabin adjustable controller I am making).
*I also had to add some additional tension to the wastegate actuator rod so that the spring tension was sufficient to hold a steady boost pressure of around 18psi yet was still able to hold a minimum of 9psi (for when someone else has to drive it  )
It now is able to hold a steady boost anywhere from 9psi to approx 19psi (depending on where I set it).
I would love one of the electronic boost controllers, but thats just another item for the list of things to get.
As far as painter go??? I don't know, I have never seen any work form J-racing so I don't know. There are a lot of paint hsops in Canberra though, so you should be able to get a few quotes.
Hope some of this info is of use.
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Location:
Canberra
Registered:
March 2004
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Re: Forged pistons
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Fri, 05 March 2004 12:42
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Yeah has been a big help unfortunately..........
I will need someone else to do that kind of work as i am so not mechanicaly minded
but i will take it in when i get my brakes done and new BOV intalled and ask if they can do this for me as well.
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