big difference between 11 psi and 15 psi?

[DJYoshaBYD]

OK... this is not bench racing.... I just want people who have a stock 14b to tell me how big of a difference between stock boost and 15 psi is....

I KNOW it has to be noticeable, but how much faster did it make your car? Did anyone dyno like this? Maybe 1/4 mile after this mod? Im just curious because after I break in my motor, im going to crank up the boost (with some fuel mods, of course..)

So.. how big between 11 psi and 15 psi?

 

[nightspeed87]

pulls harder... bov is a little louder.....

I noticed you mentioned you were breaking in an engine
Read this before you do-

http://www.mototuneusa.com/break_in_secrets.htm

( I did my break in under this technique and had good engine/compression results. Besides a dying turbo that may have had something to do with breakin in a motor on it...)

 

[v2ner]

You'll feel a little difference on the butt dyno and then after a couple of days you'll be used to it and it will feel slow again. Trust me, 27psi is slow to me now...can't wait to do 35psi. Then again, the turbo is also a factor too...that's another story. Usually 1 psi = ~10WHP.

 

[DJYoshaBYD]

I already read it...

OK... but HOW much harder? like nite and day? like, intake, headers, exaust on a stock B16a honda different? or does it just feel "a bit nippier?"

 

[b00stedtalon2]

Toss a fuel pump on your car, either a Walbro 190lph or a rewired stock Evo 8 fuel pump (201lph) and put the boost at 17-18psi safely.

 

[b00stedtalon2]

I already read it...

OK... but HOW much harder? like nite and day? like, intake, headers, exaust on a stock B16a honda different? or does it just feel "a bit nippier?"

I'd say a bit nippier.

 

[nightspeed87]

Or just wait till you get injectors and a larger turbo then have your way with boost instead of pushing the stock injectors limits.

Like the other guy said it will feel faster once you first do it, but after a couple days everything starts feeling the same...

And by the way dont compare it to a B shit teen, im mean 16 honda because whether 15psi on a 14b feels slow to you or not youd likely pull on any all motor honda you encounter just with a few mods such as exhaust and intake.

If i were to bench race to quench your thirst about this question
From 11 to 15 psi its safe to say you at least gained 20 horsepower ( and I was being conservative supposing you only got 5whp per lb since its a 4 psi increase. )
But that is only " SUpposeing"
you have all supporting mods to extract maximum hp per lb on your 14b set up.
And depending on other conditions such as tune, you could possibly gain even more from that increase... ( which would likely feel better than intake/ exhaust on a honda )
But i wouldnt like to suppose to much with hp figures therefore honestly every car is different, and every condition is different, the only way to know is dyno thats why this would be bench racing.

 

[DJYoshaBYD]

that is wack... I would assume that 4 more psi would make at least 20-25 hp... super weak... still going to do it though.... haha

I plan on taking it to 17 daily when I get the fuel pump and SAFC (getting at the same time most likely)

BUT DONT STOP!!! Id like to hear everyones opinion on this (no offense to those who already chimmed in... thanks)... keep them answers rolling in

 

[v2ner]

I already read it...

OK... but HOW much harder? like nite and day? like, intake, headers, exaust on a stock B16a honda different? or does it just feel "a bit nippier?"

Well, a B16A with those mods are gonna give you around 10WHP and 2FT/LBs of torque. 11psi to 15psi would be about 30-35WHP (because it's a lower boost level). Bolt-ons are overrated for Honduhs.

Toss a fuel pump on your car, either a Walbro 190lph or a rewired stock Evo 8 fuel pump (201lph) and put the boost at 17-18psi safely.

Do this and everytime you floor it, the injectors will flood your cylinders a bit and the car will lag. It will feel like it's pulling better on 60% throttle. Most people overlook and misunderstand this concept.

 

[v2ner]

that is wack... I would assume that 4 more psi would make at least 20-25 hp... super weak... still going to do it though.... haha

I plan on taking it to 17 daily when I get the fuel pump and SAFC (getting at the same time most likely)

BUT DONT STOP!!! Id like to hear everyones opinion on this (no offense to those who already chimmed in... thanks)... keep them answers rolling in

...and you would think that for someone who compares to a Honduh motor wouldn't think 20-25HP would be weak.

 

[DJYoshaBYD]

well... I used to have a mildly built (full bolt-ons, Toda cams, type-r intake manifold and TB, Fully gutted 88 hatch) B16a honda... so I am spoiled.... it hit a 14.6 with bald tires and a full tank of gas.... thats why I compared it to that... I want to be able to smoke my old car, and since my car stock hits, like, a 15.0, I just wanted to know if I could do it on a stock turbo, since I am all wheel drive and I get way better 0-60 than my old beast...

 

[v2ner]

Check the times list...14B = 10s on a gutted car. 11s = on street. Welcome to the DSM world.

 

[DJYoshaBYD]

its not weak at all... it just the way homeboy described it... 20-25 hp was just "a bit nippier"... 25 hp to me in a gutted honda would make a STUPID difference... I would have to assume that it would make a world of difference, though...

 

[nightspeed87]

Well, a B16A with those mods are gonna give you around 10WHP and 2FT/LBs of torque. 11psi to 15psi would be about 30-35WHP (because it's a lower boost level). Bolt-ons are overrated for Honduhs.

I agree. Thats similar to what I was implying

Do this and everytime you floor it, the injectors will flood your cylinders a bit and the car will lag. It will feel like it's pulling better on 60% throttle. Most people overlook and misunderstand this concept.

Explain....?

... I would assume that 4 more psi would make at least 20-25 hp... super weak... still going to do it though.... haha

I plan on taking it to 17 daily when I get the fuel pump and SAFC (getting at the same time most likely)

BUT DONT STOP!!! Id like to hear everyones opinion on this (no offense to those who already chimmed in... thanks)... keep them answers rolling in

The larger the turbo and the more efficient the motor ( supporting mods )
the more gains per lb of boost youd recieve.
I mean suppose you dont have the right intake/ exhaust set up, You might not get 10whp per lb, more like 5.
Or say you start getting into the 20 + psi range on a 14b from 20 to 21 psi Id doubt youd get 10whp considering your
already heating up the air too much ( less power ) Or if your pulling timing, even less power , you may even loose
power going from 19psi on a 14b to 21psi if your intake temps are too hot and your pulling timing... This is an all so random topic.

Suppose every 1lbs only netted you 7 whp on a 14b.
Then suppose on say a 18g, every 1psi may give you possibly 12 whp.
Then say on a 60 trim ever 1psi could possibly give you 25 whp...
Youd never know.

Its too random man, it comes down to you having to just start looking at how much
air your flowing to determine your efficiency.

 

[DJYoshaBYD]

that what I figured as well... I mean, with the right mods, I have seen people on here pushing WAY more power at 15 psi with a 16g than 17 psi with a 14b... I understand its all in how its put together... lots and lots of variables

 

[v2ner]

The upgraded FP is already over-running your system with fuel because you don't have an AFPR or a good fuel controller of some sort. So you could imagine what would happen once you floor it. Even the AFC is not good with this.

 

[v2ner]

that what I figured as well... I mean, with the right mods, I have seen people on here pushing WAY more power at 15 psi with a 16g than 17 psi with a 14b... I understand its all in how its put together... lots and lots of variables

Just remember, your top HP is useless with a crappy powerband. So depending on what your goals are should tell you what you need to shoot for.

 

[DJYoshaBYD]

well, getting an AFPR is a must when getting an aftermarket fuel pump... thats just what I was taught.... Too much pressure and it will force more fuel out for the amount of time the injectors are open... which is understandable if you are maxing out your injector duty, right?

 

[DJYoshaBYD]

o... well right now all my cash went into the motor... so I wont be spending BIG bucks for any major parts soon... Im going to do my own IC piping (simple), add some gauges, stereo, and turn up the boost a bit (after I rewire my fuel pump).... maybe even make an exhaust for it...

 

[v2ner]

well, getting an AFPR is a must when getting an aftermarket fuel pump... thats just what I was taught.... Too much pressure and it will force more fuel out for the amount of time the injectors are open... which is understandable if you are maxing out your injector duty, right?

There are ways around maxing out injectors such as bumping up fuel press./running higher octanes. Not all cars will need an AFPR though.

 

[nightspeed87]

The upgraded FP is already over-running your system with fuel because you don't have an AFPR or a good fuel controller of some sort. So you could imagine what would happen once you floor it. Even the AFC is not good with this.

What? Maybe im lost, but I thought fuel pressure over run only occurs once you let off throttle and the restrictive fuel pressure regulators return hole isnt large enough to submit all the fuel thru causing some to still dumpsinto your engine cause a rich state once you let off the gas.
Id didnt think this affect conditions when your currently giving it gas.

that what I figured as well... I mean, with the right mods, I have seen people on here pushing WAY more power at 15 psi with a 16g than 17 psi with a 14b... I understand its all in how its put together... lots and lots of variables

Yep your on the right track now.
Its not always about how much boost your trying to ram in, it wont matter if the turbos
too small, or if you have too many restrictions... Boost is just compressed air,
it all comes down to how well the system flows as a whole.
Flow comes down to stuff like - how well the head flows ( cams )
how big the turbo is, how many rpm you can rev out to, how well flowing your intake/ and exhaust system is, or even
how deep your stroke is-
and then and only then once you have all that taken care of, then you can achieve max
hp per lb of boost on your set up.

Ive seen a dyno sheet were a stock 1g running 15psi with only fuel pump upgrades and knN filter and exhaust, gained 15whp just from putting a bigger throttle body elbow and hardpipes just because it was so restrictive.

 

[v2ner]

o... well right now all my cash went into the motor... so I wont be spending BIG bucks for any major parts soon... Im going to do my own IC piping (simple), add some gauges, stereo, and turn up the boost a bit (after I rewire my fuel pump).... maybe even make an exhaust for it...

If you can make I/C pipes, you can make an exhaust. Very very easy. Just make sure you get the right material and the right kind of welding...thick too.

 

[nightspeed87]

If you can make I/C pipes, you can make an exhaust. Very very easy. Just make sure you get the right material and the right kind of welding...thick too.

My whole exhaust is a custom made 3in ( including dp )

There are ways around maxing out injectors such as bumping up fuel press./running higher octanes. Not all cars will need an AFPR though.

This is true.

well, getting an AFPR is a must when getting an aftermarket fuel pump... thats just what I was taught.... Too much pressure and it will force more fuel out for the amount of time the injectors are open... which is understandable if you are maxing out your injector duty, right?

Which is why ppl get 190s such as myself. A 190 doesnt generaly require afpr,
but I managed to find a high pressure 190 which still gives me a little bit of overrun sometimes.

 

[DJYoshaBYD]

yeah... the co-owner of my little shop has a really good welder, so thats not a problem... I want to make my own IC piping for my car, perfect it, then sell it on my site....

OOO YEAH... what can I do about that elbow on my 1g 6bolt throttle body? can I get a bigger one somehow, or do I gots to mod it my self? MMWWAAAHAHAHAHA

 

[nightspeed87]

yeah... the co-owner of my little shop has a really good welder, so thats not a problem... I want to make my own IC piping for my car, perfect it, then sell it on my site....

OOO YEAH... what can I do about that elbow on my 1g 6bolt throttle body? can I get a bigger one somehow, or do I gots to mod it my self? MMWWAAAHAHAHAHA

get a 2g elbow for starters.
Some vendors sell even larger ones than that. You will need hardpipes with either though
your small stock 1g intercooler (hoses) I like to call it, wont work with a larger elbow...
Or you can put a non turbo 4g63 tb with no elbow and customize your own elbow
and attach it together with a coupler like you would on an n/t engine with an intake hardpipe....
Maybe someone else can fill you in, gotta go !