Eventuri development

[Eagle7]

It just feels like rough carbon/fiberglass

The key area to smooth out is where the air contacts the sidewall to make a turn, and that's the silicone connecting tube which is definitely smooth inside. Compare the inside of their tube with the factory one, and it's night and day different.

 

[Speedy Emira]

Speed dimples like a golf

That’s a good guess but works because the golf ball is moving through the air so slightly different. The dimples create a turbulent boundary layer of air around the ball as it flies, which delays the separation of air and allows the ball to slice through the air with less friction.
With airflow moving through an air intake it’s similar to flowing through the ports in a head and the smoother the better.
If it was for a NA engine I’d say maybe worth smoothing out but for forced induction you would get hardly any improvement even if glass smooth.
Someone with CF knowledge may be able to advise if it’s possible to sand the interior to smooth it out as I’m no expert. I know about fibre glass and that can only be done effectively by gel coating.

 

[Time2Fly]

Well the Eventuri guys themselves said it was fine and just matters that the tube before the supercharger is smooth.

 

[tnbuilder]

Anyone concerned with installing this with the type of filter it has(no pre-filter)? Comparing this to the stock with the angel hair. Will direct water spray be an issue with the Eventuri one?

 

[VL3X]

Anyone concerned with installing this with the type of filter it has(no pre-filter)? Comparing this to the stock with the angel hair. Will direct water spray be an issue with the Eventuri one?

Nah, that stuff is never really an issue unless you're going through a torrential hurricane or driving through water higher than your air filter with your foot on the throttle. I wouldn't worry about it and always remove the stock air filter restrictions when I buy a vehicle.. or just buy an aftermarket open air intake.

 

[tnbuilder]

Nah, that stuff is never really an issue unless you're going through a torrential hurricane or driving through water higher than your air filter with your foot on the throttle. I wouldn't worry about it and always remove the stock air filter restrictions when I buy a vehicle.. or just buy an aftermarket open air intake.

Guess I should have stated when washing the car...those vents get pretty dirty and I wash them out good with direct spray.

 

[VL3X]

Guess I should have stated when washing the car...those vents get pretty dirty and I wash them out good with direct spray.

Ah, makes sense. I assume the intake duct work has some drain holes, but I would avoid shooting water directly up the side vents. The filter should sit a little higher than the vent as well, but I'm not 100%. I doubt it's an issue though.

 

[silent cilantro]

Yeah there is a decent sized drain hole in the eventuri intake housing before the filter.

 

[GRP]

The factory intake is sealed up nearly the same way but has drain holes as well so its a non issue imo.

 

[kitkat]

While you've got the car on the dyno, here's what would be very useful.

Dyno run 1 - Stock: A baseline run with the car stock, including air filter, 3rd cat, muffler and all.
Dyno run 2 - GRP filter: Next, the only change being your drop-in air filter.

Dyno run 3 - GRP filter and 3rd cat delete: Now with your drop-in filter still installed, remove the 3rd cat (leave the stock muffler).
Dyno run 4 - Stock filter + 3rd cat delete: Keep the 3rd cat delete, but re-install the factory air filter.

Dyno run 5 - Stock filter + 3rd cat delete + titanium muffler: Now add your titanium muffler.
Dyno run 6 - GRP filter + 3rd cat delete + titanium muffler: Now just switch the air filter to the GRP.

Dyno run 7 - GRP filter + 3rd cat + titanium muffler: Next, just put the 3rd cat back, and keep the titanium muffler.
Dyno run 8 - Stock filter + 3rd cat + titanium muffler: Now just switch the air filter back to stock.

The above series of runs will cover the combos for the differences with your products (GRP) versus stock. I didn't include the Eventuri due to the hassle of switching out the stock air filter system with it. However, after you've done the runs above, you already have all the data with the stock air filter. Now you just need to swap out the stock air filter system with the Eventuri, then do runs with your 3rd cat delete and muffler. If you've kept the car as it was in Dyno run 8, then you could do as follows:

Dyno run 9 - Eventuri + 3rd cat + titanium muffler. (only change compared to Dyno run 8 is the Eventuri)
Dyno run 10 - Eventuri + 3rd cat delete + titanium muffler (just delete the 3rd cat)
Dyno run 11 - Eventuri + 3rd cat delete + stock muffler (switch back to the stock muffler)
Dyno run 12 - Eventuri + 3rd cat + stock muffler (just put the 3rd cat back)

Unless I've missed something, all of that would cover all the possible combinations with air filters, 3rd cat and mufflers. It's a lot of wrenching, but if you follow the sequence outlined above, it would be the least amount of wrenching to get all the possible combos.

If you DO go through all of that, I would HIGHLY RECOMMEND to anyone who makes their buying decision based on your work and results, to BUY FROM GRP. Even if someone can get the Eventuri for a few bucks cheaper from somebody else, if you've used Greg's tests to make your decision, do the honorable thing and support him. I can already tell you Greg, I'm halfway towards your titanium muffler. I like the tone and sound I heard on your website videos, but those were with the 3rd cat delete. I'm not going to delete my 3rd cat because I don't want the car louder. I want to hear your titanium muffler with the 3rd cat installed. If it sounds reasonably close in volume to the stock muffler, I'm in. I'll order one from you.

Everyone better buy one of Greg's intakes, filters or exhausts after this I can't imagine spending 2 days with a hot engine and exhaust trying to swap out parts for the sake of showing some gains to some internet forum users with comparable conditions.

 

[Hell4Leather]

Ah that's not gonna cause much turbulence. It all gets shoved into the supercharger that's gonna compress the air anyway.

That’s why I’m curious about the gains an Venturi design gives. The forced induction would overcome any resistance from the standard version. Not sure how much more air gets in above what the blower is capable of.

 

[Eagle7]

Everyone better buy one of Greg's intakes, filters or exhausts after this I can't imagine spending 2 days with a hot engine and exhaust trying to swap out parts for the sake of showing some gains to some internet forum users with comparable conditions.

It's for more than just me or a few forum users. This is the kind of info that can sell products. Intakes and exhausts are two of the most common mods people want to make. For these two particular types of mods, they're almost always bought together. Being able to show with actual test results what each product adds, and how they add together can help a potential customer make a buying decision. There are already thousands of Emira customers, and more being added. I put together that list as the kind of info I would want to know if I didn't have or know anything, even though the only thing I'm actually interested in buying is the titanium exhaust.

And I totally agree; if Greg does this, people should absolutely buy from @GRP. At prices of $1,545 for the Eventuri, and $2,499 for the titanium exhaust, that's a nice little sale. If having the test data listed with the products helps to push more sales, it would be worth it.

 

[GRP]

Doing all of the variations you mentioned on the dyno wont really be feasible in one trip since the exhaust cant be swapped on the dyno like the intake/filters can.
Next week I think we will do our runs with totally stock exhaust, drop in filters and both intakes. Then schedule another return trip with the decat and muffler installed to do it all again.

 

[Eagle7]

Doing all of the variations you mentioned on the dyno wont really be feasible in one trip since the exhaust cant be swapped on the dyno like the intake/filters can.
Next week I think we will do our runs with totally stock exhaust, drop in filters and both intakes. Then schedule another return trip with the decat and muffler installed to do it all again.

Yeah I figured it would be a two day event. Just to be TOTALLY selfish, if you can do one with the Eventuri, 3rd cat installed and your titanium exhaust, that would be the one I want to see (and hear). Thank you in advance for being a trooper and doing these!

 

[Eagle7]

That’s why I’m curious about the gains an Venturi design gives. The forced induction would overcome any resistance from the standard version. Not sure how much more air gets in above what the blower is capable of.

The supercharger can only force as much air as it has available to it, within the extremely limited time it has to do it. There are 12 intake valves (2 per cylinder) that are opening and closing in fractions of a second. The supercharger needs to be able to get a lot of air very fast to keep up the air pressure necessary at the ports of the intake valves as they open, so they can pull in all the air possible in those fractions of a second. The Eventuri is designed to not just allow air in, but to facilitate the airflow speed to keep the pressure up at the intake of the supercharger.

Based on the comments I read, it seemed the biggest area that needed improvement was the silicone connecting tube between the airbox and the supercharger, which is why Eventuri spent the money to design and manufacture theirs. Even though their intake is expensive, I can honestly say it works and works well.

 

[brett_g]

As a customer who has purchased the titanium exhaust, cat delete, and eventuri - I am just stoked to see what the power numbers will be just to know my "seat of the pants" dyno is accurate once everything gets installed!!!

And for what it's worth; the reality is it's almost comical that those three parts are priced where they are coming from a 991.2 GTS; A full titanium exhaust and intake for that car would have been easily 3x the cost. That is my absolute favorite thing about this platform - the barrier to modification entry price is SO much lower!

 

[hellasf1]

Doing all of the variations you mentioned on the dyno wont really be feasible in one trip since the exhaust cant be swapped on the dyno like the intake/filters can.
Next week I think we will do our runs with totally stock exhaust, drop in filters and both intakes. Then schedule another return trip with the decat and muffler installed to do it all again.

Any update on the results?

 

[GRP]

Any update on the results?

Check out our section on the forum for the full write up.

 

[Time2Fly]

Those clips holding the wire loom to the air box are the worst. Two of them separated and fell into the engine bay.

 

[ef_arime]

Those clips holding the wire loom to the air box are the worst. Two of them separated and fell into the engine bay.

Lmao. I feel the same. I chucked mine and used zip ties instead. Speaking of stuff falling into the engine bay…, I’ve got my washer fluid cap somewhere down there in the abyss.