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Discussion Starter #1
I have t3/t4 turbo, with Tec2 management

Whats level of boost would be considered safe-ish, for stock pistons, and what levels are darn right risky ?
I'm running 8psi now, is anyone running more on stock pistons?

what boost could I run if I buy stronger pistons ?
 

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Well, Shiv took his RS with stock internals to 12 psi. That is way too much for anyone without as much tuning experience as Shiv.

I would say 8 psi is just about the limit, depending on how well the car is tuned, I don't know. All you want to get is new pistons? With JUST new pistons, you could probably take it to 16 or 17 psi before issues such as valve float and lack of proper ability to get air in the cylinders give you trouble. Rods might be at the threshold of going at that point too, that would not be good.



Graham
 

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Also, Shiv had a 99, I don't know what year you have but the 2000 and 2001 internals are said to be significantly more fragile.

However, with proper engine management and NO KNOCK you can run lots of boost - 10 - 12 psi probably. More with higher octane (racing) gasolines.

Knock (detonation, pinging, pre-ignition) is the killer, period. No matter what. Even the best pistons, rods, rings, and crank cannot match knock. So, be sure you have properly tuned things and then go for it... slowly.

Personally, when I turbo my car, I'll have a knock guage, boost guage, and maybe EGT guage.
 

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at apex, on throttle
'99 RS, '02 Legacy, '10 'beca
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Even with great tunning I myself wouldn't go over the base 6.5 Psi or so (give or take 1 Psi) without money in the bank to rebuild the motor.

I must say, I'd be surprised if I wouldn't be happy with that low of boost on a 10:1 EJ25... but I guess others aren't.

I'll let you know if I'm happy, since I'm picking up a properlly done RS-T and selling off project wagon.

I wouldn't run more than you are daily without money budgeted to rebuild the engine and maybe a spare car for transportation.

Thanks - Jon
 

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2000 BRP RS-Swapped
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Discussion Starter #7
actually it is a shiv tec2 setup, with parts from bspec, its been tested to 10psi with no knock, but I think its too risky, and run it at 8psi.
Which is very nice BTW :) 8psi, 225 hp 244 lbft on a dyno, and possibly a little more when driving, when intercooler is working properly.

I'm just curious as to what is possible, thanks
the thing about the power is its great to have, I love it, but its addictive, once you've had it for a while, there comes a time when you want, a bit more.....
 

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Jonnathon,

What bits are from B-spec? Curious, I have a 8.5 to 1 forged bottom end and with 12 psi I am only making 200 and 240 or so on Shivs new dyno. Plus, I am running a new TEC 3. Are the numbers for real or are you taking someones word for it? What is the comp ratio of the engine? What dyno was this car tuned on? Was it cold or hot weather the day it was on the dyno? I have heard from the grapevine that Shivs dyno reads much lower than others. I wonder if our numbers are close.
 

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Discussion Starter #9
this was tuned at Brainstorm in LA (http://www.miata.org/cmt/bsp/), and shiv was down there on one day too, he supplied the initial engine map, and brainstorm tuned it. Their dyno does give lower results than other dynos so I've been told.
But it also compensates for temperature, and altitude differences.
I can only trust what I've been told by them and the printout, but I have no reason to doubt.

The t3-t4 turbo, up/down pipes, BOV, flywheel, clutch, intercooler, wastegate, boost controller, fuel pressurizer, injectors, intake piping/filter,2.5" pipes, & cat were all from bspec (as well as other odds & ends such as guages)
Also ,I have scoobysport exhaust.
I still have stock compression. My intercooler is topmount, but bigger than most

here is dyno chart, , its 221 hp & 244 lb/ft, sorry for slightly wrong quote earlier


 

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Well, that explains why you have more power at 8 psi than my set up at 12 psi. You are running stock comp ratio. Interesting how much CR plays a role in over all power tuning. You have the same size turbo and nearly the same engine management. Yet you make more horse power and we nearly have the same amount of torque. This may also be the diff between the dynos used to. Also hot day versus a cooler day. Well, I am gonna crank up the boost I think to 16 psi on the 3rd at Shiv's place. Plus the TEC 3 supplied boost control will fianly be hooked up for proper tuning. Wish me luck.
 

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not to steal the thread or anything but hayscoob are you hooking the solenoid up yourself and if so would you mind taking a few pictures if you have the abilty. I just got mine and am planning to install it soon and i cant find any intructions on how to hook it up. Once i get that and the fuel rails installed its back to vishnu for some more dyno tuning.
 

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Well, I have the solenoid hooked up on the passanger side firewall and the wires go through the fire wall to the TEC 3 under the passanger side seat. As for the vacuum hoses, they go the the wastegate and such. There is not much to take pics of. The wastgegate is buried under all of the hoses and stuff and is hard to see. So pics wont do justice.

If you are in the bay area, you could meet up with me at Shiv's place and take a look there. I will be there on the 3rd at 11 am or so.
 

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hey hayscoob i was hoping you could look at this pic of my solenoid and tell where things get hooked up cause i have no idea.




the nub pointing to the right says pump.
 

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Well, I can't right now. My car is at the body shop. Some A-HOLE back his/her sport ute into the trunk. I hope to get it back some time this week. If I remember, I will try to take a pic of the solinoid and trace where the hoses go and such.

Paul...
 

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Sorry to hear about your car, theres nothing worse than when shit happens to it when its not your fault. Anyways id really appreciate the pics and such.

Thanks agian,

-Marc
 

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I called this morning and the car is still not done. Man, I hope the car is done this week. Otherwise, I will have to re-schedule with Shiv this next Monday.
 
Silver 2K RS Coupe
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RS25.com said:
Also, Shiv had a 99, I don't know what year you have but the 2000 and 2001 internals are said to be significantly more fragile.
........Personally, when I turbo my car, I'll have a knock guage, boost guage, and maybe EGT guage.
More fragile hugh? That figures. I guess that is one way they offset the cost of the rear LSD.

Don't forget the A/F ratio gauge James! :)
 

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Marc,

I got my car back today. I looked where the solenoid is and there is no way it will help you by taking a pic of it. It's buried under a buch of flex loom and tubes and wires. It looks like a dead squid covering it up. Oh well...
 
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