Hey guys, I'm new to this, so be nice
What would be ideal WHP/BHP i can expect from the engine without damaging it? What would be the limit?
Thanks

 

400 wtq is the excepted max on a stock block .

 

Questions like this are tanamount to how high is up? I am somewhat of a noob myself, but there are a plethora of threads about this. Golden rule seems to be to keep torque under 400. Also, keeping boost levels to a safe amout is the way to go. I am going to shoot for about 400 hp/350 torque on my new 2011 Evo GSR.

 

My friend, this is a tough question to answer as not all 4G63 engines that come from the manufacturer withstand the same amount of abuse. I have seen some engines make +450wtq without throwing a rod and I have seen engines making +/-400wtq and throwing a rod. There is no clear cut answer. I for one, I threw a rod in my first EVO on the OEM shortblock and I was making about 380wtq. The 4G63 block typically responds well when peak torque is around the 4,200-4,500 RPM range. The smaller stock frame turbos make peak torque well before this and sometimes this is what creates a nice "window" in the stock block. My personal threshold on the stock bottom end is 370wtq.

 

Sorry pure evo but he has a 4b11 evo x :-)

 

Opps...

My fault.

I fell victim of failing to pay attention to details.

 

For the 4b11, it does follow suit similar to the 4g63(these are still the stronger block IMO) on rpm/peak torque characteristics. Since all dynos are different, its hard to say what the actual tolerances are on torque. Most failed block accounts that I've heard/read about(usually due to bent/snapped rods) are all around 375-400wtq or higher on smaller framed turbos.

I don't believe(not 100% sure on this) its a one time over-rev, and/or high load peak torque stress that causes engine failure. But I do believe that every time it happens it weakens the rods that will eventually fail.

Having a stock or stock frame turbo will make peak torque lower in the power band. This in effect will cause more stress on the rods(as pure evo explained already).

Full bolt ons alone will get you towards this torque limit quite easily. Tuners familiar with the 4b11 block usually dial back the torque for these reasons. Granted, you won't have the optimum bragging rights on dyno sheets, but you can brag about still having a motor.

I wouldn't recommend ever accelerating hard into boost in 4th or 5th gear from 2-2.5k. This is where a lot of high load stress will start.

This is as much as I know on the topic for the most part. Please enlighten me if any of this isn't quite right.

 

Those are the numbers I'm gonna shoot for as well. I will be more than happy with 400-425whp

 

I'm at 402hp 360tq on the stock engine.2011'- 10MR.

 

Thanks, that makes sense.
I think imma start with the exhaust system, intake, and re-maping the ECU and that should get me up there.