describes plumbing a bleed valve into a Nissan Skyline GT-R and is incorrect.
When a bleed valve is placed inline to the factory boost control solenoid (or
even after it) the following happens...
- Valve fully open - boost is exactly what it was before
- Valve fully closed
- boost is regulated by wastegate spring
- Valve somewhere between the two -
boost is between the two
I have no explanation for the results obtained by Julian Edgar. Perhaps in
his installation process he bypassed the inline factory restrictor, which
regulates boost to a maximum of around 8 psi? The reason I mention this is that
the article is still readily available and people may still be getting
The valve installed in that article is
not a bleed valve. It functions as a flow control valve - it is fitted upstream
of the boost solenoid and can be adjusted to increase the amount of air bled by the factory boost solenoid. Have a read of
Bumped Up Boost
this story outlines the same approach with similar results.
More Bang for BA
I’ve bought a new Ford BA XR6
non-turbo (though now I wish I did buy the turbo...). In the next six months I’m
looking at spending up to AUD$5000 to get more performance out of the BA. I have
been told to go turbocharged or supercharged. What would you advise and what
type of performance would I get at the end? And, yes, if I have to spend more
than planned I will.
First weigh up how much you'd need to spend to achieve X power and
consider resale value and reliability compared to a factory
be reluctant to spend heaps on the car for the above reasons - but that doesn't
mean you can't have fun! As always, start off with a high-flow exhaust, modify
the air intake and maybe revise the management system with an interceptor. We
imagine this could give around 10 - 20 percent more power. If you want something
big, a CAPA BA Falcon supercharger kit would probably be the go at a bit
over $5000. This is said to give 305kW (together with an upgrade exhaust).
Compare that to a XR6T with 240kW and similar torque and you've gotta be talking
12s over the quarter mile - traction permitting.
Another Blown Beemer
Just a short addition to
2004 Engine Epic - BMW Engines
... After the M102 turbo
engine came M106, which was a 3.5-litre six with 8.0:1 compression, lower boost
(0.4 Bar), Motronic management, electronic boost and timing control with knock
sensing. It made the same power as M102 but more torque at lower revs. It was
employed from ‘83 to ‘85 I believe.
Big Banger GTi
I have a question about an engine conversion. I'm owner of Suzuki Swift GTi
1.3-litre DOHC 16-valve but the bottom-end is damaged. I have two bottom-ends
that I can replace it with – one is from G16A 8-valve and the other one is G15A
16-valve. Both are a perfect match to the GTi transmission after making some
alterations but the G16A bottom-end has the oil pan on the other side compared
to the G13B and G15A. Which would be the better one to put with the GTi head?
Would the G16A have more power and torque with the G13B head?
Have a read of
We suggest the G16A engine as the platform because, yes, it will give more
torque than the G15 and we’ve seen these combos work well. You might want to
check out the resulting compression ratio when dropping the GTi head onto the
8-valve G16A block. Perhaps the G13B or G15A oil pan could be fitted to the G16A
bottom-end - or maybe one could be made to fit without too many mods.
I read one of your older articles
(A Shot in the Integra's 'R's)and your comments on
pod/cone air filters producing no power gains. I’m unsure about the matter. I've
always thought that on the dyno, the car is stationary so the air in the engine
bay should be fairly static. But, once on the move, air enters from the front so
the engine bay temperatures should be cooler. Maybe some in-gear acceleration
tests are in order to compare performance of factory air boxes and exposed
pod/cone air filters?
The amount of airflow through the
engine bay on a chassis dyno depends largely on the size of the dyno fan.
Generally, though, there is less airflow than typically experienced driving down
the street. This causes heat soak, which kills performance if there’s an exposed
under-bonnet filter. The same will happen on the street in stop-start
The fan you show in
Fan-Forcing Your Intercooler, Part 1
1974 to 1979 VW Combi cabin blower from vehicles fitted with the Type 4 1700,
1800 or 2000cc engine. It’s the same as in a 914 Porsche. This fan comes
controlled by a dash switch with, I think, three speed settings. It can be found
in the engine bay above the motor.
Thanks for letting us know! We’ve
added a note to the end of the story identifying the fan.
I read with interest
The Delta Throttle Timer Breakthrough
have thought up a possible project. I was wondering if there is a low current
motor that can turn a shaft 90-degress when voltage is applied and then, when
the voltage shuts off, will snap back to the previous position.
The reason for the question is that I want to try to build a butterfly for
the exhaust that is linked to the TPS so that if the voltage on the TPS rises
above 4 volts the butterfly will snap open. In part throttle driving it will be
closed for quiet operation. I basically want the unit to operate as close to WOT
as possible and, when you lift off, to close the butterfly within about 10
In this application, you could use a
simple timer circuit and throttle position switch. However, the Delta Throttle Timer
(which looks at rate of accelerator movement) could also be used. Use an electric
solenoid and a spring to open/close the valve .