Everything You Can Do To Improve Lag

[discopotato03]

True Scotty but in this day an age (better computers/injectors/E85) I rather have an RB26 with a 9.5 static CR than the standard 8.5 . It wouldn't turn it into an RB30 but if the quench zones were done properly it should make more part throttle torque all else being mechanically equal - on E85 .

A .

[juggernaut1]

Will increase lag.

High gas speed is where is't at... 1 inch runners, 6 into 2 before the flange so there is no open areas for the gas to slow down. etc.

Are you saying extrude honing increases lag or the stock manifolds increase lag?

[Ben C34]

Are you saying extrude honing increases lag or the stock manifolds increase lag?

Increased volume and therefore lower gas speed will increase lag

[GTRPSI]

Opening port diameters will slow down gas velocities, in effect giving slower than normal gas flow speeds.

Too small can also be a restriction, its a balance point.

[juggernaut1]

Gee's what volume increases as you guys seeing.

I've had it done to ex hsgs and the volume is miniscule/immeasurable.

[XRATED]

Compressed air injection into the turbine wheel.

I'd really like to know if anyone has ever tested compressed air injection with simulated exhuast side pressures/gas flow?

... goes off to find my dive bottles.

[XKLABA]

Change to stock cams and stock diff gears, the more load you put on the motor the better the turbos respond, its why your car spools harder in 4th then 1st

It takes pressure to make pressure so the quicker you can pressurise the exhaust manifold the faster the turbo will spool

An electric super charger post turbo/s sounds like a good idea and fairly simple to manage under the guard before the intercooler

[discopotato03]

I reckon whats happening there is that a more fully opened throttle again a load that isn't allowing the engine speed to increase (high gear) means better cylinder filling so more heat energy to drive the turbine .

If you had your car on a hub dyno and could load it so it couldn't accelerate in any gear the result should be the same . Against a light load an engine accelerates easy with less throttle and not as much energy to the turbine so it accelerates more slowly - lower boost .

A .

[GTSBoy]

Well, Disco......pretty much what you said, but more easily said as "load makes boost" and in lower gears you can't actually achieve quite as high a load at any given rpm as you can in higher gears. For the reasons that you gave above (ie in lower gears the car accelerates merrily away before it can achieve the loads you get in higher gears).

Edited July 17, 2014 by GTSBoy

[XGTRX]

To the OP. What particularly did you want to achieve. Is it off boost torque when daily driving, faster acceleration, are you falling off boost in between gear changes? What is it exactly.

The characteristics of a car is a sum of many parts not just the engine. So what do you want the car to be like?