Weighty Matters
Your article "Modifying Speed-Sensitive Power Steering" prompted me to sign up as an AutoSpeed member immediately. I am facing a problem with my very recently acquired Mitsubishi Airtrek Turbo-R which is inflicted with power steering that is way too light. Other than that, I'm very pleased with my new toy. Now comes the tough part - as the power steering is not speed sensitive, is there any other areas that I can look at modifying without compromising safety or reliability? 'Pulleys', 'solenoids' etc. have come up but I am not sure as to how to proceed and will greatly appreciate any advice.
Philippe
Singapore
The way that manufacturers alter the power steering weight in different models is to change the torsion bar stiffness within the rack. We have heard that a bypass around the pump will increase steering effort, but we wonder about its effect when you need to suddenly input steering (eg in a swerve and recover). So sorry, but we've never seen a power steering system effectively modified for more effort, other than the electronically one we covered in the story.
Injector Flows
I am going to add larger injectors to my Pulsar and have decided to try your method of tricking the ECU by adding a pot to the output of the MAF ["DIY Bigger Squirts"]. Unfortunately I'm still not sure what will happen when my engine is at full load. Will the ECU give the injectors everything they've got when I punch the throttle (because it is no longer in closed loop operation)? I thought I read somewhere that the ECU determines the injector pulses for wide open throttle while in closed loop mode, which means it won't use the injectors at full potential. If this is the case, then there would be no point in installing bigger injectors. Can you clarify this issue for me.
Sean Pope
Australia
The pots move the airflow meter's signal so that at full load, the larger injectors are opened a lesser pulse width, therefore giving the correct mixtures. In other words, the system is actually set up so that full load mixtures are correct. However, while it is a very effective method given its $5 cost, these days for any car other than a very budget one there are much better approaches available, eg chip re-writing
GTR XU1 Originality
Re Torana GTR XU1originality. A reader mentioned that all XU1s must have black interiors, this isn't true, there was a doeskin (white colour), grey and brown also especially in these 3 cases they were August 1973 Bathurst versions.
Terry Hewitt
Australia
Hard Times
Hi! Just a quick line to say how much I appreciate your site. I log on periodically when my Fiat X1.9 project gets too much for me and I need inspiration to keep going. I'm fitting a turbo100kw GT Starlet motor into a fully restored X1.9 and it ain't as easy as it fist looked. DUH! you say! I know, I should have known that before I started but I NEED more power and the old Fiat motor and gearbox just didn't have what it takes. It has the excellent handling but that just ain't enough. Please keep the articles coming.
Steve
Australia
On-Road Tuning?
Firstly, your articles are great. I do enjoy reading them from time to time, depending on what my mood is. Although I do find the tech DIY issues more interesting most of the time. Hence me looking forward to your new section on technical stuff. Is that going to be ready soon? Do keep up the good work.
I seek your opinion/advise on the installation of a Unichip in my car. It is a local variant of the Daihatsu Terios. Basically it's a 4WD. I have spoken to the local agent/distributor and we basically have agreed on everything. The catch is that these guys only have a 2WD dyno. And my car is a permanent 4WD. So they promise me that on-road tuning would serve just as well.
I don't seem to doubt them. However, I cannot but remember your words, if you do any modifications have them verified with a dyno. In short, I feel a bit cheated in not having a piece of paper to prove to my mates that my investment did bring about an improvement. Is there anything you can comment on on-road tuning? Is it safe/reliable? What are its pros and cons to a dyno tune? Which is better, on road or dyno?
Thanks in advance,
Adrian Oon
Australia
The best outcome will be achieved by a combination of dyno and road tuning - on the dyno for the high load tuning and on the road for the transient tuning (eg ignition timing and fuel enrichment/enleanment with sudden throttle changes). We would not be getting tuning done entirely on the road - it certainly can be done, but replicating all the possible load/rpm variations is far more easily and quickly done on the dyno.
Power Formula
Is there any formula that calculates Hp at the motor (or wheels) from 1/4 mile terminal speed times. I ran a 15.849 @ 140.33(87.20) and am curious. NB: FWD 2ltr 5 speed
Matthew Hutchings
Australia
See "The Best Performance Determinant"
Review It Again
Could you please retest the Racelogic Traction Control system? Your impressions were a short 4-5 lines which barely gave any real opinions. Try it on a single turbo Supra or something of that nature.
Darren Foo
Canada
AWD System Technicalities
I read your article on the Holden AWD system and wanted to point out a few technical flaws.
An open differential is a rotational speed varying device and does not vary the torque. Each wheel sees the same torque no matter what, it is only the speed, and therefore the power that is varied. Think about this. Jack up the back of a Commodore/Falcon base model (RWD, open diff) If you run the engine, both wheels turn. To stop one wheel turning, you must apply a torque equal and opposite to the torque going to that wheel, correct?
Well, the other wheel is now turning twice as fast as before, but still only sees the same amount of torque as it did before. It is now producing twice the power as before (for equilibrium) but not seeing twice the torque.
I know this concept is hard to grasp, and you may well disagree with me, but it is a fact.
So your comment that:
Imagine that one of these cars is placed so that one wheel is on a slippery surface. The driver dumps the clutch and that wheel starts to spin. However, as soon as it's turning faster than the other wheel, it is automatically braked. This immediately sends lots of torque across to the other wheel, which is therefore getting most of the power. The car drives off. So on this car the torque split from side to side is being controlled by the braking of individual wheels.
is inherently wrong.
It should read:
Imagine that one of these cars is placed so that one wheel is on a slippery surface. The driver dumps the clutch and that wheel starts to spin. However, as soon as it's turning faster than the other wheel, it is automatically braked. This immediately sends lots of POWER across to the other wheel, which is therefore getting most of the power. The car drives off. So on this car the POWER split from side to side is being controlled by the braking of individual wheels.
The brake that you talk about provides the counter-torque which sends the POWER to the other wheel. When one wheel spins, the torque is still going to the wheel, it is just resisted by excess grip, which allows the other wheel to spin, increasing the power to the other wheel relative to the "stuck" wheel.
I understand that many people have trouble with the concept of TORQUE and POWER, and I also understand from reading your book and many editorial posts that maybe you are watering down the technical aspects somewhat, as I am sure you already understand what I am pointing out here.
For my own peace of mind, I would appreciate a reply from yourself as to whether you agree or disagree with my comments.
By the way, I did not "learn" about diffs from the other site, I work in the transport industry and have helped design AWD systems for heavy transport vehicles. Hours of testing and design have proven this theory. Now, I also want to point out that LSD devices DO vary the torque split and CAN send more TORQUE to one wheel. But your comments were about OPEN DIFFS, and that is what has been discussed here.
Anyway, I hope this helps.
Keep up the good work
Daniel Simms
Australia
Thanks for that - and you're right.
Mini EFI
Rob Wignell (Response, last week): You've probably heard this before, but if you want to adapt a mini engine to use fuel injection, the best thing to do is get an 8-port head like the Arden 8-port, or a KAD twin-cam, then there are no probs with the siamesed intake ports, and a whole lot more flow. The Arden head was used by the BMC works teams so it's still authentic. You could also try to source the injection setup from a late model throttle body injected Mini, which were sold in Britain up until the Mini ceased production in 2000.
Gary Barnes
Australia
Great Work
Great work on the Spin Cycle article, hopefully at this point some readers will realise that AutoSpeed isn't as biased (if at all!) as some of the other automotive publications out there. Although: it will be a cold day in hell when readers don't write in to criticise an author giving his personal opinion which is clearly identified as such (and then often countered with a perhaps someone else would think this...)
It's good to see that you can still keep your sense of humour, especially when a manufacturer asks "Has Julian Edgar grown up yet?". A comment like that could almost be defined as slapstick - it's hilarious. Hmmm, I couldn't really tell from the photograph, but how broad are your shoulders?
Keep up the great work.
Ronald Marks
Northern Territory, Australia
(The land of open road limits and no demerit points... Yet.)
Subaru Swap
How's it going? Been a member of your site now for over 2 years and I think it's fantastic! Keep up the good work. Quick question regarding engine swaps. I have a '95 GX Liberty Sedan, standard EJ22 motor, 5 speed box. Is it possible (and more importantly feasible) to drop the EJ20 motor out of a WRX and into the Liberty? Is there fabrication or strengthening of the driveline needed? Given the Liberty already has the all-wheel-drive layout, ABS and 4WS does this make any difference, or is it a waste of time?
David Richards
Australia
In our opinion on relatively late model cars it's always best to start off with a factory package - so in this case the older RS or the newer B4. That way you get the right brakes, right suspension, right fuel pump, right ECU, better resale....and probably in overall terms, at a lower cost.
Go Take a Look
Please review my website: www.rh9.com.au
Jason
Australia
Porsche Mufflers
I have been a subscriber since March and really enjoy your web magazine. Your recent article on the muffler exchange peaked my interest as I drive a 1997 C4. Mine is normally aspirated, but I too changed the mufflers on my car and I was wondering if any of the dyno shops you used for the muffler articles have any history with the non turbo 3.6 air cooled motor. What I am looking for is validation that I have done the right thing. I am also looking for information on chip tuning or ECU reprograming, fact or fiction. Your comments would be appreciated. Thanks.
Levino Tittaferrante
Canada
We don't have any results on that engine. Sorry.
Tech Boxes
Thanks for a great magazine. Would it be possible for to put the specs of the cars that you feature, performance, suspension, etc, etc, at the end of your articles so that we can get a better insight into the cars that you feature.
Yusuf Khan
South Africa
It's something that we will certainly consider doing.
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