Blow Off Valve For Mr-2

[iDavidx516]

good sh*t chili, haha show them what's up. i think BOV's are pretty ill. sounds so intimadating. anyways everyone is entitled to their own opinion but it is kind of childish to go around calling other people names lol. btw i'm still waitin on that race chili lol

vtec power !! =DDD btw jekyl got a sick car haha check you mr2 owners out lata, PeAce~

[JekylandHyde]

To each, their own.

I'll never understand why people are sooo worried about other people.
Frankly, I do not care what other people do to there cars (or WHY they do it!), unless I can learn something from them.

As for people who do things that I do not like ... so be it. In my opinion, they just make me look better. I would hate it everyone had the exact same taste.

That being said, I was just as guilty as anyone for buying BOVs because they were "cool" and I bought into that they increased performance, etc ... but the bottom line is, I am interested in performance. PERIOD.

That being said I would like to clarify a few things:

Originally Posted by scarecrowX

does the OEM valve perform better than aftermarket valves? yes. is it a significant gain in performance? that's debatable.

The OEM valve does not give you a gain inperformance since you already OWN it. Paying $250+ for an aftermarket valve will cost you performance.

Real racers are interested in squeezing every possible ounce of performance out of their cars. I am lightening Hyde over the winter and one of the pieces I took out weighed less than 3 lbs. Is that going to give me drastic improvements? Hell no. But when you figure I have takev out of 10 pieces that weigh less than 3lbs, you are talking about close to 30 lbs ... added to other items that I have changed, modified or removed and I am looking at close to 150 lb weight loss. I should be over 200 lbs by my first race day.

So at what point are you "ok" with paying money for parts that you know are inferior? If it cost your 1 HP? .... 3 HP? ...10 HP?

Originally Posted by scarecrowX

but forget the actual imperical data, bench racing is just fine when you're demeaning someone over the internet for reasons you can't back up yourself.

I am speaking from 10 years of expereince of owning/modifying/racing turbocharged MR2s thank you. I have tried several BOVS and have all kinds of wonderful problems (screwed up idle, valves getting stuck open and let me sit on the side of the road, power on shifts not being as smooth, running rich, etc). I paid a good $$$ to have my car dyno tuned ... I am not about to throw that out of whack for a cool noise.

To each their own.

[JekylandHyde]

Originally Posted by HondaChili

ok mr2 chick, although BOV does sacifice performance, it doesnt do it where the car falls behind drastically.

Again, how performance are you willing to sacrifice? 1 HP .... 3 HP ...5 HP .... 25 HP ....?
You mentioned buying it because you like the sound and you like the overall presentation of it and that is fine. I have done the same thing in the past. I agree the noise is cool ... the irony is that at the moment people hear your cool, they look at your car and see the overly rich black exhaust puffing out. So you basically draw attention to your ride at the precise moment that performance is less than optimal.

Originally Posted by HondaChili

If we are talking about giving your car parts where performance would only matter, then well everyone would be driving around in 13 in rims. why do people get 17 or 18 in when clearly the 13's give you more speed.

That is not an accurate statement. Rim size only affects "speed" by their weight. As long as the overall diameter of rim + tire stays the same, there is no affect on speed unless the rims weigh a different amount. That being said, you can buy lightweight 17" rims.

Now, if your overall diameter of rim + tire is SMALLER than spec, you will LOSE speed, GAIN acceleration and LOSE gearing which is not good for drag racing. It happens to be great for autocrossing, which is why you see autocrossers with 13" rims and low profile tires. It allows them to use an extra gear on tight courses.

Now if your overall diamter of rim + tire is LARGER than spec, you will GAIN speed, LOSE acceleration and GAIN gearing. OEM rear tires on an MR2 is about 24" tall, when I installed my drag radials (almost 26.5" tall) I gained over 2-3 mph in SPEED on the drag strip. The gearing affect (torque) helps with the launch and giving me time to comprehend 1st gear.

The logical reason people go to taller rims (like 17"s) is to improve handling performance, not straightline speed. Assuming you keep the over all diameter of rim+tire the same, a taller rim will give you less side wall (lower profile tire) which will give you less flexing under load (cornering) and increase your handling. This is true for the average street tire. For the MR2, 15" rims with RACE TIRES are probably the best bet for handling, bit not realistic on the street.

All that being said HondaChili, if done right, a larger rim will increase performance.

Originally Posted by HondaChili

On top of that if everyone were to go out and buy the things that will only gain them performance, then you'll have a crap load of the same cars with the same mods, now where is the fun in that?

100% agreed. To each, their own.

Originally Posted by HondaChili

An import show would be pointless to have if it were under your ideals, no?

Agreed again, but not everyone is into showing. You know there are people out there that are fanatical about having 100% stock cars? .... 50 years from now, their cars will be worth more than any of ours. Again, to each, their own.

[quote=HondaChili]Just asking for a lil courtesy thats all.QUOTE]
Amen.

[JekylandHyde]

Originally Posted by iDavidx516

btw jekyl got a sick car haha

thanks man.

[scarecrowX]

Originally Posted by MR2Chick

So no one is allowed to have an opinion anymore. There's always someone who will get offended. I digress, my original statement was a generalization.
Hondachili decided to take it personally, that's his call. There is no set definition for the word "ricer" or what is and is not "rice". If you think that it means that people who think that they get 30hp (AT THE WHEELS) from an CAI, or 45hp (AT THE WHEELS) from an exhaust, then fine. That can be your definition. Mine, on the other hand, involves pointless, overdone modifications made to the engine and/or body of the car. I just don't understand why you would sacrifice the performance of your car for a sound. Everyone joked about the "turbo whistle" or the other muffler attachment that Bubb Rubb was peddling. This falls into the same category.
Hondachili himself said that a real ricer buys a nitrous kit without even hooking up the bottle. So in my head, it comes out to the same bloody thing.

where did i say no one was allowed to have an opinion? could you please point that out for me? my point is that you are making fun of him because of his opinion. why shouldn't he take it personally?
the problem, in my experience, isn't the ricers. it's the performance nazis who think everyone should conform to their vision of what makes a cool car, and whoever doesn't is automatically stupid and/or a ricer. THEY'RE the ones talking the shit, not the ricers. trouble is, they're also the ones who get overly defensive when someone calls them out. if you're going to belittle people on message boards, you better be able to take it as well as dish it out.

Originally Posted by jekylandhyde

I am speaking from 10 years of expereince of owning/modifying/racing turbocharged MR2s thank you. I have tried several BOVS and have all kinds of wonderful problems (screwed up idle, valves getting stuck open and let me sit on the side of the road, power on shifts not being as smooth, running rich, etc). I paid a good $$$ to have my car dyno tuned ... I am not about to throw that out of whack for a cool noise.

fair enough. problem is, my car didn't come with an OEM valve. it came with an assortment of aftermarket valves. i simply worked around that. i've driven several MR2's with and without the OEM valve, and while the performance of the OE valve is better, the performance of the car is not necessarily better because of it. i've got a greddy type-S on mine. when i bought the car, it was plumbed back into the intake. it drove just like any of the MR2's i drove with the OE valve, being that it is of the exact same design.

so i worked out a little system and vented it to atmosphere, just as an experiment. now it drives better. not just a little better, it's a night and day difference. to me, driveability is a major component of any performance car. the difference was WELL worth it. there is no black smoke when i shift, nor does the engine stumble or stall when i shift (i've done the "push the clutch and let it stall" test and it passes with flying colors. the rpm never drops below idle). as a fringe benefit, i get a pretty cool noise.

it's really sad that some people aren't ok with that- especially when it's not their car.

[MR2Driver]

Did you just say it drives "better?" You must have an incredibly imaginative butt dyno...

[scarecrowX]

since when do you need anything more accurate than a butt dyno (even an imaginative one) to tell the difference between the way it was and "HOLY FUCKING SHIT IS THIS EVEN THE SAME CAR!!??"

if i were claiming a slight change, i could understand your point, but i'm not. it's a fundamental difference in the way the car drives- especially before the engine is up to temp.

[JekylandHyde]

Originally Posted by scarecrowX

i've got a greddy type-S .... with the OE valve, being that it is of the exact same design.

They are not even remotely close in design.
The GReddy works on a Spring (which is the one major flaws of aftermarket valves). The OEM works on Air. Push enoguh pressure throuh that greddy and it will open under boost. The more air you push into the OEM the harder it stays shut.

One of the HKS units copied the OEM design for using air pressure to keepthe valve closed, but it still does not have the by-pass feature of the OEM valve. No aftermarket valve does.

Originally Posted by scarecrowX

so i worked out a little system and vented it to atmosphere, just as an experiment. now it drives better. not just a little better, it's a night and day difference.

You are kidding yourself or you are kidding us or your OEM valve was broken.

Originally Posted by scarecrowX

if i were claiming a slight change, i could understand your point, but i'm not.

Ironic. A few posts ago, you agreed the OEM valve was better but not enough to be noticeable or worth while. Now you are claiming that a valve (you admit is inferior) suddenly has a significant night & day difference better than the OEM valve?! Your arguments do not add up.

Originally Posted by scarecrowX

it's a fundamental difference in the way the car drives- especially before the engine is up to temp.

The BOV/BPVs affect operation under boosted conditions.
If you are boosting before the engine is up to temp you are asking for major trouble. Boosting on a cold engine is unwise.

[JekylandHyde]

IF YOU TRULY BELIEVE THIS:

Originally Posted by scarecrowX

where did i say no one was allowed to have an opinion? could you please point that out for me? my point is that you are making fun of him because of his opinion. why shouldn't he take it personally?

WHY DID YOU POST THIS:

Originally Posted by scarecrowX

since when do you need anything more accurate than a butt dyno (even an imaginative one) to tell the difference between the way it was and "HOLY FUCKING SHIT IS THIS EVEN THE SAME CAR!!??"

[JekylandHyde]

scarecrowX,
When you disagree with the argument, you demand real emperical data, but when you offer a point for argument, your but dyno is enough?!

Look at your posts:

On page 1 of this thread you say:

Originally Posted by scarecrowX

in fact, the people who more accurately exhibit the "ricer" mentality are the ones who think their factory BPV is making them faster. does the OEM valve perform better than aftermarket valves? yes. is it a significant gain in performance? that's debatable. i'd like to see some lap times to back up the claims that these other valves are so far inferior to the OEM that they would cost you time on a track. but forget the actual imperical data, bench racing is just fine when you're demeaning someone over the internet for reasons you can't back up yourself.

PAGE2 YOU SAY THIS:

Originally Posted by scarecrowX

since when do you need anything more accurate than a butt dyno

Is this the same person talking?!?!

[scarecrowX]

wow.

okay, let's begin.

They are not even remotely close in design.
The GReddy works on a Spring (which is the one major flaws of aftermarket valves). The OEM works on Air. Push enoguh pressure throuh that greddy and it will open under boost. The more air you push into the OEM the harder it stays shut.

One of the HKS units copied the OEM design for using air pressure to keepthe valve closed, but it still does not have the by-pass feature of the OEM valve. No aftermarket valve does.

i stand corrected. mine does have a spring. it also has boost/vac ports on both sides of the diaphragm. it's not the exact same, but it's similar enough. my apologies. if set up with a one way restrictor like the OE valve, however, it will operate in by-pass mode as boost pressure remains in the lower port with vacuum in the upper port. they are not as dissimilar as you make them out to be.

You are kidding yourself or you are kidding us or your OEM valve was broken

no, i just know a few things about my car that you don't. your assumption is understandable though. the argument is unimportant either way..

Ironic. A few posts ago, you agreed the OEM valve was better but not enough to be noticeable or worth while. Now you are claiming that a valve (you admit is inferior) suddenly has a significant night & day difference better than the OEM valve?! Your arguments do not add up.

sure they do. why is there a difference? because there is a fundamental difference in the way i have mine set up when compared to the OE valve. you're also forgetting something- at no point did i say that the valve i have works better than an OE valve under equal circumstances, nor did i say that the car performed better because of it. more on that in a bit..

we are talking about two different things here. you are talking about parts. i am talking about how those parts are set up. THAT is where the difference lies. if you read that post more carefully, you'll see that i'm being consistent in what i'm saying. perhaps the OE valve set up the same way would work even better. you've assumed that i ruled that out when i did no such thing.

The BOV/BPVs affect operation under boosted conditions.
If you are boosting before the engine is up to temp you are asking for major trouble. Boosting on a cold engine is unwise.

BOV/BPV's most certainly open and close under vacuum conditions. you said so yourself earlier in your post. the remainder of your statement is irrelevant as i never said anything about boosting on a cold engine. i am sorry though, i should have made that more clear.

as for the

IF YOU BELIEVE... THEN WHY DID YOU POST...?

, i really don't see any relevance there whatsoever. i'm not making fun of anyone by saying what you quoted (which is the point of the first post you quoted me on). honestly. they are totally unrelated. could you elaborate on your point further? i do not see how those two posts are even remotely related. maybe you interpreted it differently than i had intended. either way, i cannot address a point that i cannot see. if you're referring to my language in the second quote, it was not in any way meant to be derrogatory to lachean, only to illustrate my surprise at how differently the car drove. again, misinterpretation is understandable. lachean, i hope i didn't offend you, that was never my intention.

scarecrowX,
When you disagree with the argument, you demand real emperical data, but when you offer a point for argument, your but dyno is enough?! ...Is this the same person talking?!?!

of course it's the same person.
i think we're just differing on the part of the discussion we each choose to emphasize.
you are asking for imperical data pertaining to the driveability of the car. i am asking, in my post, for imperical data pertaining to performance of the car, valve vs. valve. one is tangible; measureable, one is abstract.
driveability is a component of performance, not performance itself. unfortunately, there is no real means of measuring driveability other than the good ol' butt dyno. why not? because there is one differing factor between every single car that driveability affects: the driver. in my case, ~i~ am the driver. my preferences regarding driveability will likely differ from yours, and everyone else's. therefore, my butt dyno is the ONLY instrument (haha i just called my ass an instrument ) on the face of the earth calibrated correctly to assess my car for me. i, at no time in any of my posts, claimed that my car performed better because of my setup (it's true, go back and read them), only that it drove better. there is a crowbar seperation between those terms, but apparently it's a distinction that few people can make.
as you can see, i'm still consistent in what i've said. i hope i've cleared a few things up. i am, however, having difficulty understanding why you're going to the trouble when you

never understand why people are sooo worried about other people...

and

do not care what other people do to there cars (or WHY they do it!)

[HondaChili]

Hmm seems like this conversation has turned into a heated argument with quotes thrown left and right. Guys, lets keep it cool. Both sides have pretty good reasons for things said, lets not start an internal conflict. Save that for the ones who actually dont know squat and come here to talk shit. In anycase, I have a Turbo XS RFL BOV, i did not actually go out and buy the thing but it came with the car when i bought it and ive grown to love it. It does have some minor kinks over the past year.
1. The valve gets stuck. The simple problem was an easy fix by aiming the horn in a downard angle.
2. It idling problems. Not as much, maybe once in a while.

SInce i have not tried any other types of BOV's im not in a place to say which gives performance or which does not. Only in my case, i KNOW im losing performance. However, Im sure that not one car (even from factory) is exactly the same. Each car can react differently to different parts. Yes, in the general sense, BOV's will take away performance. But there can also be a car out there that takes it well? maybe? I mean factory "freaks" exist, dont they?
As for the 13 in rim statement i made earlier, yes it was a general comment. I stated it to prove another point without ragarding the statement with care.
Once again, lemme remind everyone this thread was just a simple question on BOV's, so lets just answer that question and let it be.

[HondaChili]

Dave ill drag you when it gets warmer... shesh , and btw i didn tknow you were on this forum.

[iDavidx516]

i am everywhere lol

[JekylandHyde]

scarecrowX, I will clarify your last question first:

I truly do not care what other people do to there cars (or WHY they do it!) in the sense that I am not concerned with people who knowingly make the choices they do.

Hondachili asks about BOVs.
He is told aftermarket ones rob performance.
He says, "OK, but I like the noise.
That bit of performance is not important to me."
I say fine. I do not judge him.
It is his educated choice to play with his car as he likes.

That being said, I am not debating your car for your sake.
I am debating your car for the masses who may be reading this thread to learn and gain information.
I am interested in education and helping.
That is my motive.

That being said, your information is still not accurate:

Originally Posted by scarecrowX

if set up with a one way restrictor like the OE valve, however, it will operate in by-pass mode as boost pressure remains in the lower port with vacuum in the upper port. they are not as dissimilar as you make them out to be.

The by-pass feature does not come into play when "boost" is in any port. The by-pass feature comes into play when there is no boost.
I really do not think you are understanding the by-pass feature of the OEM valve.
There is a section on it here:
http://jekylandhyde.madpowaz.com/bov.htm
No aftermarket valve has that feature.

And again, a spring design valve will never be as efficient as the one based on air. It can not respond as fast. It can not respond as sensitive (that is why the OEM valve farts - it can "partially" respond).

Under enough pressure the spring design will not hold.
Comparitively, the OEM holds stronger the more pressure you add.

Originally Posted by scarecrowX

why is there a difference? because there is a fundamental difference in the way i have mine set up when compared to the OE valve.

Of course! They are entirely different valve designs!

Originally Posted by scarecrowX

BOV/BPV's most certainly open and close under vacuum conditions.

No.
Valves are designed to open when the throttle plate closes and there is boost pressure in the intake system.
That is not a vacuum.

The OEM BPV will open under normal driving vaccum (unboosted driving) to let air go the opposite way through the valve (compared to when venting boost) toward the intercooler.
That is the by-pass function.
The air is allowed to "by-pass" the turbocharger.

So, NO, BOVs do not open under vacuum unless the spring tension is not adjusted properly.
They open from boost pressure when the throttle plate closes.

Originally Posted by scarecrowX

the remainder of your statement is irrelevant as i never said anything about boosting on a cold engine.

You clearly discussed the improvement your valve made on a cold engine.
If you are discussing your GReddy valve's performance, you most certainly are implying that you were boosting.
The GReddy valve does not open (or do anything else) except when venting boost.
Boosting on a cold engine is bad.