draxcaliber

if my motor wasn't built, how would it even exist? HAH! got you on that one don't i?

i know terrible joke, i just wanted to post in this thread so i can read the updates and information here later. great stuff guys, keep it up, much easier than cracking a book. i'm on summer vacation, i'm not supposed to be actually learning.

turbogsxr750

There are many things that go into a built engine that can affect the power that is made. Say for instance you blow up your TC engine. You then order rods and pistons from wherever. You then take your engine to a local run of the mill machine shop and have it repaired. they do the typical machining such as honing the cylinder wall aligning the mains and resurfacing the block and balancing the crank.

On this particular setup once completed and installed with all the components that we on the engine to start adn the tune exactly the same you will acutally lose power. Not much but it will be measurable. The reason for this will be the forged pistons and rods are heavier that the factory pistons. More rotating weight means more power loss.

Now on the other hand you can make more power with the same example from above if you know some of the machining tricks that free up the power. Some of the tricks used are more for a racing application but that is beside the point. Such as increasing bearing tolerances from .0012 to .0022. You can knife the crank which removes the weigh from the farthest point on the crank and also allows the crank to cut throught the oil as apposed to whipping the oil.

there are other things that would break budgets of most like nicacil coatings on the cylinder walls and needle main bearings.

But the majority of the time on a built (shortblock) you will not see a difference in power with out changing boost levels or adding another power adder.

turbogsxr750

Changing the cylinder head has the ability to do alot of different things. TCs can be limited here due to the fact there are no after market cams yet. So you can only work with what you have. A good ported and polished head alows you to make the same power but on a lower boost level. Say for instance you are running 18psi with a stock head. You then decide to get a ported head. You will make the same power with that head but will only be running 14psi (just a theoretical number). All boost is is a level of restriction. with the ported head there isnt as much restriction so the air moves more freely and faster but you are still getting the same amount of air in the cylinder which make the same power.

On another note, when it comes to compression ratio the one most talked about is static which everyone worries about way to much. everyone feels they have to drop compression ration down in order to be safe with boost. Big misconception. if you have a built engine (longblock) that is built properly you can have a compression ratio of 16:1 and still run 30-40 psi from a turbo or supercharger. what really plays a big role in forced induction engine is the dynamic compression ratio (compression while the engine is operating). Static compression is what majority of people have heard of. Well how often do you build 20 psi when the engine isnt moving? NEVER. I am not saying that it isnt important but only have of the process. Once again with the TC 2az-fe there isnt much of anything you can do to change the dynamic compression since it is all done with the way the cam is ground and timed into the engine.

These are just a few points i thought i would share and let open to discussion.

Brad

paul_dezod

Brad, the only thing you failed to mention is the fact of then having to have tuning dialed in even more precisely and the need to switch to race gas sooner. The biggest benefit for the DD guy that wants to run more boost on pump is lower compression.

Otherwise, good points.