turbodriz said:
I would agree there needs to be more information like this for those who do have the knowledge. And so is the question. How to squeeze extra power out of the 7m?
The short answer, money, lots of it...
The longer answer:
An engine is an air pump. That's really all it is. Get it to move more air (and the corresponding fuel) and you'll get more power.
There are two ways to make an engine move more air. Move more air per revolution, or run more revolutions in the same amount of time (ie. rev the crap out of it).
We've covered why it's not a great idea to spin the 7M at 8000 + rpm in threads like this:
http://www.supramania.com/forums/showpost.php?p=180719&postcount=18
So since spinning it faster isn't the greatest of ideas, getting it to move more air per revolution is the best way to do it.
First and foremost, lay a good foundataion.
That means a balanced & blueprinted motor. When I say balanced, I mean balanced. Pay your machinist the extra cash to get your pistons & rods balanced down to 1/2 a gram or less.
Use forged pistons.
Use forged rods. Shot peening and beam polishing will help a good bit.
Be sure all tolerances are set to the tight side, and use an extended break in period. (This is another topic, but if you want longevity, this is the way to go - race builders build 'em loose because they don't have the luxury of break in periods)
Ensure there's
more than enough fuel (both at the injector and pump). Use calculations like in this thread:
http://www.supramania.com/forums/showpost.php?p=179880&postcount=7
Size your turbo appropriately for your horsepower goals. Make sure it will operate inside it's max efficiency range for what you are trying to make.
Don't cheap out on the intercooler.
Porting & polishing the head helps. Custom ground cams can make a world of difference.
The ultimate exhaust for a turbo car is straight through. The way the pistons scavenge, etc is more dictated by the turbo itself. So behind the turbo, make it big, make it straight and eliminate all restrictions possible.
Do the same on the intake piping, cut down on restrictions.
There's no mystery to building a monster. Anyone who hung around in Atlanta back in the 90's knew about the 3 white MKIII's that ran around together. Those 3 white Supra's were Will Neely, Eric Varah & myself. Building a 650 - 750 rwhp 7m is not that difficult.
But it is expensive and requires an almost psychotic attention to detail.
[strike]If anyone wants to build a really killer 7M PM me and I'll spec it out for you down to the smallest detail. I guarantee you that if you (and your machinist) follows the spec I give you and you'll make all the power you were looking for and the car will last a long time. But be serious. I don't have an unlimited amount of time and it takes a while to really "design" a motor, not just throw together a parts list.[/strike]
Edit: I apologize, but I had to rescind the offer above... I just don't have the free time that I did when I originally posted it, and I really hate having to disappoint people by saying no.
