To start with the rods like everyone says are the weak point strength wise... But your stock fuel delivery system is also limited to this point... Tho it is not necessary to change the pistons it is better to have a piston rated for forced induction apps as the compression rings are seated lower to keep them cooler. 400whp is about the limit of the rods and fuel system... I achieved just over 380whp on a 57trim without any injection and when the motor was pulled to get built, one rod was bent. So either at this is a sign of obvious knock.

The compression ration has nothing really to do with building a forced induction system, but you will need to know what kind of fuel you will be using in order to run an appropriate compression ratio... I have built several turbo cars using 11.0-1 pistons... only problem is there will be massive torque and you will spin tires all day long and you will be running some kind of injection or e85 for everyday driving... If you have e85 readily available, I say go with highier compression pistons and you will see some amazing spool. If I ever burn a piston (which hopefully wont happen) I will be going to a higher compression piston and running e85 on 20+psi daily.

Remember when you run forced induction you are effectively raising the compression by adding more air... So if you run 15psi on 8.5-1 pistons thats is roughly the same as running 10 on 9.5-1 pistons.

Currently I run 16psi on a 60-1 without a tune daily with no issues... But im sure that because the ecu is dumpin all the gas it can into the cylinders whenever I barely tap the gas.

 

There is a difference in your comparison. Effective compression ratio with 9.6:1 pistons 10psi boost = 16.1:1 and 8.5:1 pistons 15psi = 17.2:1. you will have to retard ignition timing even more on the 15psi setup to decrease the chance of detonation. Are you saying you were running 16psi on a stock block is so this would put you at 20.1:1 effective compression ratio which means you would have to run race fuel or retard the ignition timing very extreme to prevent detonation? Are you running any engine managment on your 16psi and has it ever been tuned, what size injectors, what fuel are you running?

 

16 psi on 9.0-1 cp pistons with 700cc deaschtwerks injectors on 93 octane. Have the greddy ultimate but it only has a base map which is good enough to drive the car... Not tuned cuz the laptop suffered a catostrophic failure due to hitting the floor from a high place lol.

There are two ways to reduce knock, (A) pull timing, or (B) add enough fuel to buffer the chemical reaction... Buffering the chemical reaction slows the combustion process thereby eliminating knock.... Usually people add some sort of injection to achieve this, I just prefer not to.

The higher octane rated fuels also do the same thing. The higher octane rating makes the air/fuel mixture burn slower (in some cases with less fuel) but with more fuel. The higher octane rated fuels have a lower level of chemical potential energy which means you will need more of that fuel to achieve the same amount of resultant thermal energy from the reaction... This is very evident with cars running on e85 or straight alcohol. These cars require more fuel volume requiring higher flowing injectors and fuel pumps.

 

i have been running 13 psi for a month or more with no problem what so ever and only 1-2 degrees of timing was pulled i think! and before htat i was running 11 lbs forever untuned professionally. these engines can take a beating. cause i know on 13 psi now i beat the hell out of my car and still running like a champ. it also depends alot on your tune.. you can run 9 psi daily but if your tune is jacked ur gonna mess up something ask CrayolaG.

 

makes more sense now bc you said untuned so it has some sort of tune just not by a shop, bigger injectors help, already broke into the engine to lower compression.

 

There is only the start up tune provided by greddy. I have a couple videos of the car on youtube... It breaks up something serious and Im sure if the motor was stock it wouldve imploded already. I did this for one reason. To show turbo to be scion tc owners that it is not necessary to spend all your money on additional safety and other bells and whistles to make power... If you spend the money in the right places on the right products. I am almost willing to guarantee that I will be able to top 400whp on the stock fuel delivery system (which I do NOT recommend for anyone thats not willing to suffer the consequenses as I am), and without injection. And I would like to be able to top 550+whp with my exact setup only modification will be to change the fuel system, and it will be done on pump gas and no injection. Anything is possible if your math and execution is on point.

 

Yo purevision...can u hook me up with ur tuner since we live close? Pm me thx bro

 

he is the tuner lol

 

Oh snap!!! Pm me i need someone who knows what they r doin!!

 

Oh snap!!! Pm me i need someone who knows what they r doin!!

 

Been running 360 WHP on pump gas everyday for almost 2 years. 100% stock motor. Take it to track during summer many times, run more boost at around 440 WHP with VP race fuels no problems at all. Again, all stock motor. These things are surprisingly strong. Keep in mind this is all on standalone Hydra ECU. I doubt it would have survived this long with a piggyback.

 

^^ a testiment to spending money on the right parts and not just overbuilding a car for limits it will never see^^

 

Hey Paul,

I know you guys sell the FIC with your kit.
Will you guys do a tune with the Ultimate for me?
I want to take advatage of the 2 step launch control.

 

its not about power its about temperature and timing and tune i have seen some at 400whp holding fine on a bad **** tune

 

umm.. ive seen a couple local tc's on 18+ lbs with stock fuel system.. and easily over 400..

 

I can see easily over on c116 but not easily over on pump gas. I plan on seeing max 430-450whp on pump gas and thats truly truly truly on the verge of self destruction. But if they did I'd love to see their setup, there always room to learn.

 

ya i will get the list of mods for u 2morrow. my tuner did his car.. they raised the boost to i think 22 lbs for a little and then raped a c6 z06 lol. hes fully built.. pnp head springs retainers etc., with full internals + sleeved with 800cc injectors

 

PM him.

 

lol, id say sleeves are more like using a condom and pistons and rods are like the pull out method, its a must.

 

So - can someone list out what the minimal mods to "safely" raise the redline about 1k? Ive been looking through a lot of posts and many people were saying that sleeving should be introduced at 400whp. Are there different kinds of sleeve jobs that make sense for lower hp setups (300-350whp)? Safety is more the key w/ me. Nothing would be worse then rebuilding an engine and blowing a hole in it. I think the going price on a used head is $300 and there seem to be many camry/tc heads out there.

With the goal of under 340whp - are there any parts that people would say "surely do not have to be replaced"? I haven't heard much about things that do not need to be done, but a lot of people are just throwing parts at engines through pure guessing.