Some of this week’s Letters to AutoSpeed
I don't need to say it again, but I will anyway... love your work! Great
articles as always - unbiased and informative.
The reason for this letter is to point out a small fact in your article Plumbing Basics, Part 1...
You show a picture of fuel hose that is rated as SAE30R7 then talk about EFI
hose. Do you know that SAE30R7 is actually low pressure fuel hose for carbie
vehicles? A lot of auto stores try and pass this standard hose off for use on
EFI vehicles - but it is not designed for high pressure EFI use! The correct
standard for EFI hose is SAE30R9. This has a working pressure of 125 psi and
minimum burst pressure of 900 psi. The SAE30R7 hose is only rated for 50 psi and
a minimum burst pressure of 250 psi. The construction of the two hoses is
different and the temperature ratings also vary.
Please read this PDF for actual specs of common hoses...
Important Safety Information
I though I would point this out because so many people aren't aware what the
Suggested Thread Sealer
Just a quick one - in your article Plumbing Basics, Part 1 you mention Teflon tape as a
sealant for threaded fittings. While Teflon is good, I much prefer Loctite 569 –
put just a drop or two of this on any fitting before you screw it in. I've never
had anything leak after using this stuff and it's much easier and quicker than
Teflon. It is a bit expensive to buy, but a bottle will last you literally
years. Hope this is useful to someone out there!
In Driving Emotion it
"(Note that if a new exhaust hadn’t been installed at the same time as the
turbo, the turbo conversion would have worked out lighter.)"
It seems that someone looked at the wrong figure here, as the turbo and
exhaust added 10kg to the car, the new exhaust weighed 15kg but the old exhaust
weighed 11kg... So, just after telling us we must take into account the weight
removed, Julian has made the same error! If the exhaust had not been changed,
the turbo mod still would have cost an extra 6kg. Immaterial still, but
significant to the article! (I think... if there's something I’ve missed, please
let me know!)
That statement was made in comparison to the supercharger installation – ie if the new
high-flow exhaust hadn’t been added, the turbo kit would’ve been lighter than
the supercharger installation. The complete turbo and exhaust installation
weighs 10kg more than the standard car.
Closed Loop Mixture Details
I purchased "Altering Closed Loop Mixtures" (Altering Closed Loop Mixtures) because this means that the
goal is to alter closed loop mixtures. I would like to do this as it would allow
a lean cruise mode. However, in the article, this was not accomplished.
Disconnecting the O2 sensor under load and then tweaking the mixture is totally
You now have a series, starting at Modifying Closed Loop Cars that Need LOTS More Fuel! Part 1. I don't want to
buy these articles if you did not accomplish modifying the closed loop
behaviour. I think the first article I purchased had a misleading title and I
wasted my money because of this. I don't want to do it again. I am very
impressed with your publication overall. I may eventually
If you use the techniques outlined in
either article and then reduce fuel pressure, or increase the airflow meter
signal, you will be able to attain a lean cruise mode that can be switched in
Golf Cart Power-Up!
I am looking for a two or three cylinder diesel engine to power a small car
(which weighs 1200lb or about 545kg). I also need a compatible transmission. Do
you have any suggestions? In case you are wondering, I want to convert a
street-legal oversized electric golf cart to diesel.
The latest engine that springs to mind is the three cylinder 800cc
direct-injection engine from the smart – its 30kW and associated gearbox should
get your cart moving! There have also been some 3-cylinder turbo diesel engines
produced by Daihatsu (for the Japanese market). Can any readers offer some more
I was reading the current AVO TT LS1 ute article LS1 TT Ute and was wondering what a
"boost pressure conservatory" is? I was thinking it was a large glass building
where genetically modified, high protein BOOST plants grow? How does the guy fit
the conservatory onto his ute anyway?
Article now corrected – substitute "conservatively" for "conservatory" ...
Electric Water Pump Issues?
I've seen your comments about the Davies Craig electric water pump Testing the Davies Craig Electric Water Pump - Part 1 but I don't know what your
issues are with them. It might have been a reliability issue which is now fixed
for instance. I'm not sure what to make of it all?
Please do a review on modifying a Nissan R34 GT-T!!!
For a couple of modified R34 RB25DETs see Sony Sound Skyline and Ripper R34