ysb02

+recommendation for Seb @ NLR. He's been boosting 'busas since they first came out and knows his forced induction.

sciff5

iTrader: (1)

Bumping this up so its not forgotten. The last time we had a thread like this it kinda died off and we never really got any answers. No one on this board may know the answers to whether this really works well or not but I doubt that with how many experienced guys we have on here.

NLR it doesnt look like posts here that often, I just hope he checks on this thread, sounds like hes done this many times before.

ysb02

The link chris posted pretty much describes what you need to do. I'm still fuzzy on how to switch ECU tunes on the fly on the factory ECU when switching between high / low boost.

Robert@G-Force

I checked with Procharger awhile back after reading that same article and they told me that using the wastegate to bleed boost off is not a good idea for the blower, seeing that the actual blower is working too hard still making the pullied boost level but the excess boost is just bleed off.

white01ss

iTrader: (37)

That's ridiculous! There's no way that could harm the blower. If anything it's easier on the gears because there's less pressure it has to fight against. As long as you aren't spinning it faster that designed to go, what's the harm?

calongo_SS

iTrader: (7)

2 or 3 bar speed density. No switching required, just tune it for the different boost levels and you're ready to go.

Mr.Big

you tune for max boost, just like a turbo car...

calongo_SS

iTrader: (7)

You could, or you could run a 2 or 3 bar and tune for each boost level independently and have things setup the right way.

Mr.Big

so turbo and S/C cars aren't setup the "right" way when they are running up to max boost??? as long as the tune, up to and including max boost is accounted for, every thing else under the max is correct... That's why/how we use boost by gear... It's very simple...

calongo_SS

iTrader: (7)

I don't think you understand what I am saying, I don't know how your car is tuned, or if you did it yourself or not.
If you are running a maxed out MAF your airflow calculations are out the window so you are only supplying fueling based on RPM. So if you change you boost level there is no way to change the fueling without changing the tune.
If you are running a 2 or 3 bar SD tune you are calculating airflow by manifold pressure also, so you will actually see changes in airflow and boost. You should tune for each boost level independently then your done. You don't just tune it at 20 psi and assume it's going to be spot on at 10 because you will never hit all the same VE cells with a 20 psi boost setting that you will with a 10 psi boost setting.
I am saying you have to include the "up to" part in your tuning, not only your max boost setting.
Not this:

Mr.Big

exactly my point...

Louis

iTrader: (7)

If you are using a MAF, and maxing it out, and then adding fuel in via PE manually, You probably have no business adding a waste gate, or the need for a Boost by gear setup, and probably you can put everything you make to the ground....

sciff5

iTrader: (1)

forget the maf guys we are figuring an SD tune

LuvmyC5

iTrader: (1)

Subscribing................

ayousef

guys, before fighting over this, think of the problem I introduced:


high-rpms, low-gear, MASH THE THROTTLE, SC boosts instantly, faster than the reaction time of a Waste-gate (which is designed to work fast enough for a turbocharger, which builds boost and goes from vaccum to full boost in say a second depending on size/lag) not instantly.

a SC'ed vehicle tuned to use a waste-gate and sees a small sudden SPIKE while the waste-gate does its job will blow-up in an instant.

Correct me if im wrong.

On a sidenote, what are SC restrictor plates?

chuntington101

have you any information to back up these claims about wastegate??? i know of turbo cars that will go from max boost to none back to max in VERY little time at all!

im not having a go by the way, just looking for information.

Chris.

sho-me speed

iTrader: (55)

Restrictor plates work rather well and haven't caused and heat problems on my set-up. I have the blower pullied for 18lbs but have a plate that restricts it to 11lbs max and my average power is substantially higher. I build boost way earlier.
The pulley change and the restrictor were my only change and it added 9 MPH to my 1/4 time.

sciff5

iTrader: (1)

thats very substantial gains, would like to hear more

Mr.Big

I agree with all that I quoted... everybody that hasn't done this AWLWAYS claims that the S/C won't hold up to the abuse, and that the IAT's will be substantially higher... JUST NOT TRUE from MY experience on MY setup (won't speak for others)... my answer is all of the above + (not on a sopa box promise) how many P1SC's do you know making above 750rwhp, on pump and methanol alone??? what works, WORKS...

Mr.Big

for sure a waste gate/boost controller is far superior and the only way to go imho... with that said, on the cheap... I designed a butterfly setup (similar to a throttlebody) in side of the filter intake just before the headunit is the neatest adjustable way to go on a budget. The tolerance doesn't have to be anywhere near close, as it'll never be all the way closed, a set screw on the outside to lock the shaft the blade resides on, a nurled adjustment **** on the shaft with a line scribed on it for blade angle (so you don't have to guess or take the filter off to see...) this concept makes adjustments on the dyno super easy and keeps you from making a bazillion restrictor plates of different sizes, to get it setup right... also soooooooooooo easy to change for more boost at the track... after all that, once again, waste gate/ boost controller is superior!!!