m21sniper

The E-ram people have gotten much better dyno runs than 3hp, and the figures have been verified by Mark Kibbort(the customer you're speaking of did not install it as instructed by eram).

According to Mark, HP is increased by about 3-6%.

Spinning two small radial fans at 25,000rpm(which the latest e-rams achieve according to Mark) IS going to move quite a bit of air.

It's still forced induction even though the gain is a max of 1.7psi in some apps. Any increase in pressure/flow above the engine/intakes normally aspirated Volumetric Efficiency IS boost.

Imo000

Chaad,

Two words: Statistically Insignificant. 3hp gain with a lot of variance is exactly that.

m21sniper

3hp isn't insignificant if you win by a nose, is it?

3-5hp is about what one should expect from port matching an intake, yet people do it, and that aint exactly cheap either.

Regardless, Mark's seen dyno runs that produced more than triple that figure(3-6%, depending on app).

SharkSkin

Mark K has stated a difference from -0.5psi in the air cleaner stock to +0.5psi with the e-ram. He has also stated that a 5 liter engine is pretty much pushing the outer envelope of what the devices are capable of. I think he saw 10-15HP gain, but I'm not sure whether that was with stock exhaust or not.

Seems the e-ram does work, and offers a small but measurable improvement. Is it worth it? That's a matter of personal preference. In my opinion, no. But, to each his own...

AO

FYI... I recently read about an electric turbo charger system. No lies. I'll see if I can dig up the article.

chaadster

Thanks, and two more words: Improper Installation!
(maybe)

Imo000

Sniper,

I agree with your definition 100%. The only problem is the validity of the data. Performance parts usually only yield about half of what the manufacture claims. This has been true with almost anything I’ve ever used in the past. 1.7 psi is just slightly over what a simple Ram Air intake system will produce at 100mph.

James-man

250 max HP for baseline seems a little low, but if the car was an automatic, it is plausible. Without knowing more about the car and the condition at baseline, it is impossible critique or to rely on 27hp as an expectation for another S4.

Just before the baseline HP curve turns down @ 4300, it looks like the measured gain is around 10 HP which is around 4%. A 3% gain is observed at 4000 RPM. I would inclined to believe that a 5% gain at or near peak is realistic and an appropriate expectation.

My gut would tell me that the 10%+ on the 27HP may be due to fortuitous circumstances - but who knows, there may be others with similar luck.

James-man

Kuhn is correct on the cost + time + effort. This is the key to whether it is right for someone to pursue or not. If it were $300 to get a sure 4% gain then hooray, but for our V8s, it would cost over $600 to get a possible 4% or whatever modest gain.

By the seat of the pants, it is hard to feel 10 HP on a 300+ HP car. It is easy to feel a 100HP gain on a 300+ HP car. $60 per HP to not feel much or $50 per HP to feel something special (super or turbo charge, or whatever). Bang for the buck requires higher investment.

I don't think that it is a matter of whether these work or not. It is a question of how well they actually work for 5L 928 applications and whether the time and money spent is worthwhile when seat of the pants evidence may be nearly imperceptible.

chaadster

Thanks, James-man,
I think it is also a question of WHEN they work... I'd love to see better partial throttle response myself, as opposed to gains at WOT.

Of course, my solution is just to press the pedal more!

James-man

Out of curiosity, I contact eRam guys and they said that the recommended installation was in parallel: one on each opening to the air box (as pictured in the first post of this thread). Series was not the primary recommdation.

I would agree that 3hp isn't particularly impressive on a $600+ investment. But if your customer is happy, even if only for perception discrepancies, good for him.

edit: sorry - I typed this before seeing someone else had addressed the series parallel issue.

chaadster

I already pointed out the in-series problem to Dave, and asked if they'd tried it in parallel.

Additionally, though, he notes his customer attached them to the MAF, suggesting they were not before the stock airbox, which also might have caused difficulties.

m21sniper

"1.7 psi is just slightly over what a simple Ram Air intake system will produce at 100mph."

True....but....

E-ram will give the gain from a standing start, and if you do have a ram air intake the pressure gain from both will work together, hand in hand to produce even more power.

I don't use E-ram, i've never used it, nor do i know anyone that has....but....the principle is sound. If the fans actually spool to the advertised RPM the e-ram system can't help but make more power until the NA flow in CFM of the motor exceeds the max CFM flow of the units, which according to mark, happens somewhere around 5.5liters of displacement.

It seems to me that the smaller the motor, the better E-ram will work.

hacker-pschorr

I thought by definition “turbo charger” is exhaust driven. A Vortec style SC is half a turbo driven by the crank. Its not called a crank driven turbo.

m21sniper

"I think it is also a question of WHEN they work... I'd love to see better partial throttle response myself, as opposed to gains at WOT."

There is no partial throttle gain. E-rams only come on when the gas pedal hits the floorboard.