Boost Tolerances?
 

Does anyone know how much boost the stock 2.0L engines will be able to handle? The consensus seems to be about 8psi stock, but what would you need to upgrade to push more boost? I can see how too much boost may cause pre-detonation, which probably causes your engine to throw a rod. :eek:

I read the thread on lower compression and higher boost, yet I do not understand how this would effect the HP output. The only thing I can think of is that with lower compression, you can add more boost without blowing the engine. But would the HP loss (I assume that there would be one) from lowering the compression ratio be worth the extra boost or is it like trading 2 nickels for a dime? Also, wouldn't lowering the compression rob your low-end HP/torque with turbo lag?

Wouldn't increasing the bore also make the engine weaker?? Seems to me that the less thick the wall, the less strong the combustion chamber. Well, now that I think about it, the pistons, rings and rods will probably go before the wall does. :)

Can someone possibly school me or point me to somewhere I can read up on engine theory? Mostly I have made relationships based upon what other people have said, and you know how reliable making assumptions and drawing conclusions from strangers is. ;):eek:

Before anyone flames you about this...... list what turbo you plan on using... otherwise your question is too general.

Does it really matter what kind of turbo it is when I'm talking about how much boost? I dunno. I was thinking about the BEGI kit.

Yes....it does depend on the size of the turbo. Larger turbo's flow more CFM, so the more boost, the more CFM, the more pressure that is being stuffed into your cylinders. The more pressure the easier things are to break. A small turbo with low CFM such as the VJ-20 could probably run 15-18psi on the FS motors. A large turbo such as the VJ-23 could probably run 12-13 on that motor.

The BEGI kit I believe is a T28 which is smaller than a VJ-23 but much larger than a VJ-20, it would probably be good towards 13-15psi on stock internals. They were saying the MP3 motor looked good for 300hp.

I thought they were using the ancient T03?

boost is going to depend a lot on restrictions also. If you are making 7 psi on a stock system and then port the cylinder head, you'll probably drop to 5.5-6 psi. I gaurantee you'll be making more power though. It's all about how much air your engine can flow through it. Remove the restrictions to flow and then size the turbo for how much air the engine can flow.

key to run hight boost is tuning.if u get stand alone and u can play with ignition maps and have knock control u can run as high as u can get before it starts knocking.biger the compresor housing the bether.biger housing generates less heat.#1 enemy of you engine is heat.when you have heat you will get knock.i think you will be able to rum around like 10 psi on like t3to4b which is used in honda world.