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Kalle wrote: ↑Fri Dec 20, 2019 12:18 pm

bug66 wrote: ↑Thu Dec 19, 2019 10:34 am I’ve seen a few cars with an extra WG on the intake, but can’t seen to understand how it works?

Yo!

Very easy to explain. It allows you to use a bigger turbo without adding lag = more power! Basically you open the boost pipe with a waste gate so that the turbo is blowing into open air = free spool without surge. It spins freely and extremely easy. Just do it and add a 98mm - 1500hp turbo

-K-

How does one operate the valve? CO2?

I think a 6266 would be perfect

Take a look at this movie: https://youtu.be/RV-RVp6kq4w you can for example control it using an 3 port solenoid controlling both your WG and your spool up valve. 100% open spool valve and at the same time controlling max boost by controlling your WG. It should, in theory, spool up very quickly and by closing the boost valve you force the charged air to your plenum. Or perhaps you can use a Hobbs switch which not allow for a lot of tuning but instead on/off.

-K-

Kalle wrote: ↑Sat Dec 21, 2019 6:51 am Take a look at this movie: https://youtu.be/RV-RVp6kq4w you can for example control it using an 3 port solenoid controlling both your WG and your spool up valve. 100% open spool valve and at the same time controlling max boost by controlling your WG. It should, in theory, spool up very quickly and by closing the boost valve you force the charged air to your plenum. Or perhaps you can use a Hobbs switch which not allow for a lot of tuning but instead on/off.

-K-

Hmm. I don’t think I’ve got any spare outputs for a second solenoid? I still need pressure to hold open the wg, so I need a pressure source greater than the intake WG spring.. can’t understand where that source should be if the engine isn’t making any boost?

I think I should have a ok spool time with the circular cutting of ignition rather than the brutal AL I have now.. no lift shifting should help also

.. no lift shifting should help also
[/quote]
AKA, "bang shifting" (in reference to the trans taking a beating or disassembling dramatically and/or noisily) or "deck shifting" AKA as the foot to the floor and not released until the finish lights are in the past or the engine or trans falls to the ground (seen that happen several times at the track).

Lee

Ol'fogasaurus wrote: ↑Sat Dec 21, 2019 9:51 am .. no lift shifting should help also

AKA, "bang shifting" (in reference to the trans taking a beating or disassembling dramatically and/or noisily) or "deck shifting" AKA as the foot to the floor and not released until the finish lights are in the past or the engine or trans falls to the ground (seen that happen several times at the track).

Lee
[/quote]


Ignition cut at the shifting points

The 2D transmission is far stronger than my current engine anyway..

bug66 wrote: ↑Sat Dec 21, 2019 10:14 am

Ol'fogasaurus wrote: ↑Sat Dec 21, 2019 9:51 am .. no lift shifting should help also

AKA, "bang shifting" (in reference to the trans taking a beating or disassembling dramatically and/or noisily) or "deck shifting" AKA as the foot to the floor and not released until the finish lights are in the past or the engine or trans falls to the ground (seen that happen several times at the track).

Lee

Ignition cut at the shifting points

The 2D transmission is far stronger than my current engine anyway..
[/quote]
I've heard of that being done but you can still "munch" a trans with the engine running or not. You are just momentarily releaving some of the engines torque and RPM at the time of shifting but the sliding gears or syncros can still be "manured" . That is a very old trick that I thought was long gone. I used to use a version of that trick when the clutch linkage used to fall out of my Chevrolets when I had to drive home w/o the use of the clutch. Works somewhat OK for down shifting when you have no other choice; kind of like double clutching when going into a straight cut first (no syncro ?) gear on a VW trans.

Lee

Bang shifting without lifting the throttle is the ONLY way to make a mouse engine with a way too big turbo go fast. If you lift the throttle once during a run you instantly loose boost and the run is over. Basic knowledge - basically

-K-

The 2D is pretty beef, with all options added. Vertigate shifter and without synchros.

A light throttle bleep and then shift should keep a small-ish turbo spooling fine. The turbo I have now spools quick when changing gears.

Kalle wrote: ↑Sat Dec 21, 2019 2:02 pm Bang shifting without lifting the throttle is the ONLY way to make a mouse engine with a way too big turbo go fast. If you lift the throttle once during a run you instantly loose boost and the run is over. Basic knowledge - basically

-K-

Good post Kallie, basically ( ) that is true! I wasn't even talking about a boosted engine just a normally aspirated mill. When the RPM drop things internally do change also then things have to catch back up... at the driver's expense.

I wonder what is going on when the engine is still sucking gas in (with the ignitions temporally turned off) but not burning it even for less than a second (at 6K RPMs that can/could amount to a lot of fuel sucked in. Is there an internal wash down or just what? I don't remember hearing any kind of a discussion normally asperated engines or blown or turbo'd engines before.

Lee

Ol'fogasaurus wrote: ↑Sat Dec 21, 2019 5:38 pm

Kalle wrote: ↑Sat Dec 21, 2019 2:02 pm Bang shifting without lifting the throttle is the ONLY way to make a mouse engine with a way too big turbo go fast. If you lift the throttle once during a run you instantly loose boost and the run is over. Basic knowledge - basically

-K-

Good post Kallie, basically ( ) that is true! I wasn't even talking about a boosted engine just a normally aspirated mill. When the RPM drop things internally do change also then things have to catch back up... at the driver's expense.

I wonder what is going on when the engine is still sucking gas in (with the ignitions temporally turned off) but not burning it even for less than a second (at 6K RPMs that can/could amount to a lot of fuel sucked in. Is there an internal wash down or just what? I don't remember hearing any kind of a discussion normally asperated engines or blown or turbo'd engines before.

Lee

More likely than not Lee, the fuel is shut off for the instant the ignition is cut. No carbys here. It's all about control.

Isn't there a lot of pressure in the fuel pump and lines to feed the injectors with the foot on the floor?

I'm asking more for information as I said, this is something I don't remember hearing any discussions about. Injectors were not in vogue as they still were being brought forward (Chev was having a lot of frustrating fun at the time) yet and turbos were just being played with at the time (Corvair shortly after '62 for example?). A lot of exotic changes to many things in the last few short years.

Lee

Pressure in the fuel system is a constant, typically around 43psi above manifold pressure for n/a and turbo. The pressure regulator and pump adjust dependent on fuel usage to maintain this differential to keep the injector spray pattern consistent

66brm wrote: ↑Sun Dec 22, 2019 2:06 am Pressure in the fuel system is a constant, typically around 43psi above manifold pressure for n/a and turbo. The pressure regulator and pump adjust dependent on fuel usage to maintain this differential to keep the injector spray pattern consistent

What I am referring to is "hydro locking" of an engine. One of the guys I knew growing up did it and bent several rods in the process (we're probably talking about close to 60 years ago now).

"https://www.carbibles.com/engine-hydrolock/"

While they are talking about water here from what I was told (years ago) that it can happen via the fuel flow also and for several different reasons. I don't remember the whole conversation as I was just getting into cars at the time (that long ago ) but since then I have heard of it happening... rarely but more than once. Even though FI control is better now days stuff still happens even with the FI's butterflies still wide open and with high pressures. As I remember carbs are somewhere around 6 - 8psi.

Lee

It's very rare to hydrolock an injection engine as the fuel pump is linked to the ecu, as soon as the ecu stops seeing a signal from an ignition source then the pump is shut off. Old carb engines, yeah no problem just park on the wrong angle and you could siphon enough fuel to lock it up

Yes that happen to my bug with a DCOE and ,happened when I left it on the trailer "wrong angle" didn't know it until I got to the Strip