285 whp!

[RallyBob]

After the oil pan gets built, and (hopefully) the oil temp/coolant temp issues are handled, then we're going to strive for some more power as well as mid-range torque.

Jack had previously chopped up a spare stock EG33 intake manifold, and I got to looking at it the other day. In terms of basic design, it looks very good, there are very generous transitions from the plenum to the runners...factory 'trumpets' if you will. The crossover valve is a moot point for our application. The engine's running vacuum is already lower than standard, and the engine rarely sees low rpms on the track. So the crossover is always open as it is. As well, the intended original application was for a relatively heavy Grand Touring vehicle with an automatic transmission, so down-low torque was a priority to the engineers.

None of those factors apply now, so my thoughts are to eliminate the crossover, and utilize one common plenum at all times. A trial bit of math also shows that the plenum volume is very small relative to the engine's displacement. I'd like to investigate the effects of changing the plenum volumes to work with the improved breathing and extended powerband of the modified engine. If possible, I'd like to make it modular (bolt-on plenum addition) for testing, so I can determine which is best for our needs. Then , once the proper plenum volume is determined, I'll make a permanent version with reworked (slight porting and polishing) internal runners.

I'm thinking of trying 80%, 90% and 100% plenum volumes...2.64 litre, 2.97 litre, and 3.3 litre. Plus or minus a few CC's....

The first step will be to CC the stock plenum, and go from there.

It won't be tomorrow, but over the next 4-6 weeks I'll see if I can free up some time to tackle this project, and will post the progress here.

Bob

[Trevor]

Originally Posted by Nomake Wan

Funny... this behavior sounds just like the behavior my car exhibits when I'm climbing a steep grade in 2nd with the throttle fully open. Or when I'm otherwise pushing the car hard, staying above 4k RPMs for long periods.

Well crap.

Jumping to the conclusion that a larger radiator as been mentioned earlier in the thread, is not a cure all and is a common misconception.

A factor which is often overlooked is the fact that production engines are designed for limited RPM. When constant RPM are raised as in competition, the average water pump speed is increased resulting in a much increased water flow at greater pressure. As a result the coolant spends less time within the radiator, when cooling should be taking place.

Longassname has referred a restrictor plate which is a means of reducing the flow rate. In the past I have overcome the problem by cutting off some of the impeller vanes from a standard water pump.

This aspect is worth full consideration.

[Trevor]

Originally Posted by RallyBob

After the oil pan gets built, and (hopefully) the oil temp/coolant temp issues are handled, then we're going to strive for some more power as well as mid-range torque.

Jack had previously chopped up a spare stock EG33 intake manifold, and I got to looking at it the other day. In terms of basic design, it looks very good, there are very generous transitions from the plenum to the runners...factory 'trumpets' if you will. The crossover valve is a moot point for our application. The engine's running vacuum is already lower than standard, and the engine rarely sees low rpms on the track. So the crossover is always open as it is. As well, the intended original application was for a relatively heavy Grand Touring vehicle with an automatic transmission, so down-low torque was a priority to the engineers.

None of those factors apply now, so my thoughts are to eliminate the crossover, and utilize one common plenum at all times. A trial bit of math also shows that the plenum volume is very small relative to the engine's displacement. I'd like to investigate the effects of changing the plenum volumes to work with the improved breathing and extended powerband of the modified engine. If possible, I'd like to make it modular (bolt-on plenum addition) for testing, so I can determine which is best for our needs. Then , once the proper plenum volume is determined, I'll make a permanent version with reworked (slight porting and polishing) internal runners.

I'm thinking of trying 80%, 90% and 100% plenum volumes...2.64 litre, 2.97 litre, and 3.3 litre. Plus or minus a few CC's....

The first step will be to CC the stock plenum, and go from there.

It won't be tomorrow, but over the next 4-6 weeks I'll see if I can free up some time to tackle this project, and will post the progress here.

Bob

Bob, once again you are applying sound logic. It is good thinking to assume that the designers knew what they were doing, and looking at improvement through adjustment to fit different parameters. Moving out of the square into new territory, requires facilities, expertise, and most of all money. These factors tend to move the issue outside of the scope of an amateur, or any experimenter with a limited budget.

Do not bite off more than you can chew, is the proverb which exactly applies.

[Myxalplyx]

Originally Posted by Trevor

Bob, once again you are applying sound logic. It is good thinking to assume that the designers knew what they were doing, and looking at improvement through adjustment to fit different parameters. Moving out of the square into new territory, requires facilities, expertise, and most of all money. These factors tend to move the issue outside of the scope of an amateur, or any experimenter with a limited budget.

Do not bite off more than you can chew, is the proverb which exactly applies.

Just remember Trevor that designers/engineers have their limitations as well. They are not always right and can only work and go as far as their company will let them. They have to make compromises for various reasons. Some inventions come from not what you know but from new ideas brought to the table. Perhaps Bob can come upon a new discovery by accident or even on purpose that can benefit the SVX community as a whole.

Even Einstein once said, "Imagination is more important than knowledge."

[Trevor]

Originally Posted by Myxalplyx

Just remember Trevor that designers/engineers have their limitations as well. They are not always right and can only work and go as far as their company will let them. They have to make compromises for various reasons. Some inventions come from not what you know but from new ideas brought to the table. Perhaps Bob can come upon a new discovery by accident or even on purpose that can benefit the SVX community as a whole.

Even Einstein once said, "Imagination is more important than knowledge."

Constraints do not imply limitations in knowledge. For sure the designers have been limited in their choices, but so is the guy trying to make improvements. On this score, Bob is displaying sound logic.

"Perhaps Bob can come upon a new discovery by accident or even on purpose that can benefit the SVX community as a whole."


I note the missing "?", but sarcasm is one thing I hate. I trust that it was not intended.

Bob is not trying to reinvent the wheel, because he knows that is futile. He is correctly bent on adjusting to suite a different application.

Please take heed of who is heading the field in the race for performance to date.

[YourConfused]

Trevor,
You hate sarcasm? You must hate me then.
How's that for sarcasm?

Good thread, good read, great info, must subscribe.

[Trevor]

Originally Posted by YourConfused

Trevor,
You hate sarcasm? You must hate me then.
How's that for sarcasm?

Good thread, good read, great info, must subscribe.

I love you.

[SVXRide]

Originally Posted by RallyBob

It's a KRC aftermarket pump. Commonly used in circle track cars. Funny thing is, it looks like the typical OEM Japanese PS pumps out there. Almost a direct fit. His is the steel version, an aluminum one weighs half as much but costs more. The Subaru pulley was apparently a direct fit. The new reservoir has greater capacity, and the return lines are now -10AN. Foamed-up, overheated fluid does not return easily, so a larger return line is needed to avoid stalling the pump due to cavitated fluid not returning. The cooler helps a lot as well.

The quickener is a Howe 'Stealth' 2:1 quickener. It's fitted within the stock steering column (welding required). Most of the rally guys have been doing this for years.

Bob

Bob,
the PS100 pump and pulley?
thanks
-Bill

[cdigerlando]

Holy crap what a story. Definitely some problems that we can expect with
our built motors and heavier cars. Are you running any sort of aftermarket
aluminum radiator? I would be curious to see how you set up your electric water pump and aftermarket power seering pump. I wonder if a larger more efficient oil cooler and a better radiator would fix your problem. Right now I'm running an aluminum radiator and a small tube and fin oil cooler. It sounds like this will not be enough. I'm not sure if the STi water pump would pump more, but it should. It might be worth a try. I'm sure this would be easy to modify to fit. The impeller is much different than that on my EG33 and EJ207 motors. You would just need to plug the outlet to the air water oil cooler.

With this kind of duty you probably need to go through the entire cooling system and improve everything that you can. Aluminum radiator, stronger hoses, high pressure cap, pump, coolant, bigger plate and frame oil cooler. All this has been mentioned. You are not pushing that much HP and weight so that should really be good enough. Anything you can do to improve air flow to the radiator too would probably help. A manual fan operator would probably help too. A buddy of mine is running a 600 HP Impreza. As soon as he slows down the temp goes up so fast the fans don't kick on in time. If they came on much lower, like at about 195 instead of 205, it would really help. Also a lot of guys are running straight water with water wetter. I didn't have much luck with this though.

Too bad about 5th gear. I really thought that the route you were going making more power with better RPMs would relieve the stress on the 5 speed. You might consider replacing the gears with hardened ones. This may be better on your budget than the 6 speed. I'm not too sure how well these work though. I'm sure there would be some good advice on Nasioc regarding improvment to the transmission.

Keep up the good work!

[RallyBob]

Originally Posted by cdigerlando

Are you running any sort of aftermarket
aluminum radiator?

Yes, the car already has an aftermarket Koyo STI radiator fitted.

I would be curious to see how you set up your electric water pump and aftermarket power steering pump.

The power steering pump was apparently a direct fit (just conveying what Jack told me). The larger capacity reservoir and associated plumbing are routed to just behind the right side headlight. The electric water pump is almost completely hidden from view, at the lower left front corner of the engine. In fact you can only see if if the car is on a lift. The space confines are definitely tight there.

I wonder if a larger more efficient oil cooler and a better radiator would fix your problem.

The aforementioned radiator has been installed for some time. The oil cooler is a Setrab unit, 7.5" tall x 13" wide plumbed with -10 lines.

I did inquire about the thermostat, and there is none fitted. The restriction is done entirely via the electric water pump. I was also not aware that the water pump can be controlled via the Autronic ECU. It can turn the pump on and off as the temperature tells it to do, and can also be set to control the fans. So even when the engine is shut off in the pits, the water pump is circulating coolant and the fans run until the true engine temp is down to acceptable levels.

Too bad about 5th gear. I really thought that the route you were going making more power with better RPMs would relieve the stress on the 5 speed. You might consider replacing the gears with hardened ones. This may be better on your budget than the 6 speed. I'm not too sure how well these work though. I'm sure there would be some good advice on Nasioc regarding improvment to the transmission.

Keep up the good work!

The real bummer is he had a tighter ratio 5th gear too. He had scavenged it from a blown-up customer gearbox. The aftermarket replacement gear is $260, but the factory gear ratio is only $95. So the budget wins out, and the car will get a slightly taller 5th now.

He is going to send 5th gear out to be 'MicroBlue' treated however. I had recommended them for his wheel bearings last year, based on my talking to MicroBlue at the PRI show in 2006. The Impreza was only averaging 2 events per front wheel bearing before they got totally cooked, while the MicroBlue treated stock bearings have 6 events on them and they are still perfect. The loads that modern racing tires put on the stock bearings and hubs is huge!

Bob

[RallyBob]

Originally Posted by Myxalplyx

Just remember Trevor that designers/engineers have their limitations as well. They are not always right and can only work and go as far as their company will let them. They have to make compromises for various reasons. Some inventions come from not what you know but from new ideas brought to the table. Perhaps Bob can come upon a new discovery by accident or even on purpose that can benefit the SVX community as a whole.

I agree the designers and engineers have limitations, and it is unfortunately usually a monetary restriction that the upper management deems necessary for them to follow. So most things end up being a compromise, unless you are building a no-holds barred supercar.

I never would have believed it mattered that much, but a close friend of my family's went to work for one of the 'big three' automakers a few years ago in charge of quality control in his respective field, and he ended up quitting after only two years because of the futility of it all. If they could make a substandard part last 90% of the required time, they would use it to save money. He would rant and rave over the safety issues (his field was electronics), but it fell on deaf ears. To them, $1 per car spread over 500,000 cars was more important than the potential for electrical fires!

Myself, I have no shortage of ideas, but certainly I have a shortage of free-flowing cash, as does the car owner. So anything I do has to be both: A) cheap, and B) cost effective. In reality it should also preferably be free and not involve outsourcing unless absolutely necessary!

Keep in mind I haven't been paid for any of this EG33 development work, it's really been just for fun. I guess I have a penchant for underdogs...

Bob

[Tim]

I'm not so keen in automotive department as I am with other things, but what about removing the thermostat altogether to increase flow?

[RallyBob]

Originally Posted by TE1221

I'm not so keen in automotive department as I am with other things, but what about removing the thermostat altogether to increase flow?

It's already been done.

Bob

[cdigerlando]

Originally Posted by TE1221

I'm not so keen in automotive department as I am with other things, but what about removing the thermostat altogether to increase flow?

He did.

Sounds like a well set up system. Good oil cooler too. Maybe a bigger one would help. The taller gear might help as well (lower RPMs). You are definitely set up to use a higher pressure cap. That should help. Might need to upgrade some hoses too though.

I was talking to a buddy of mine who has a 600 HP Impreza. He also has some heat issues. He was talking about how a lot of the nascars are running 250 degrees regularly in their motors Yikes. How do your competitors do with their cars and heat?

[shotgunslade]

I have a stock SVX radiator and stock-type, but new hoses. Would I have any issues with using the 24 psi radiator cap?