Drax240z

Doesn't matter.

I think part of the problem is most higher end dyno's actually come with a fan, mine came with 1 of the 14,000cfm fans. I believe the cheaper inertia dynos just come bare bones to keep the price down, and people don't really budget for the secondary equipment needed. Though in reality I got one of my fans used from an equipment rental place for $200, and a 2nd new one for $300... It's not a massive amount of money.

LOL... nice.

Awesome post Olie! I had never thought of using 1/4 and 1/8 mile times to approximate ramp rate, but it's a brilliant idea. (too bad we have no strips around here!) I cannot speak for other dyno's as to how they determine the ramp rate. It sounds like Mustang dyno's use weight, rather than an acceleration rate. But for a DD dyno you could just give them that number and away they go.

I'd say it's a bit of both. Mostly the operator and his ramp rates, but I'm under the impression that with most machines it is quite easy to put more load on the car than you can on the steet. (I certainly can) For example, when set what I refer to as the "ramp rate", I can choose anything from 1.0km/h/s to more than 20.0km/h/sec. What this means is how fast the dyno will allow the car to accellerate at a given load. (usually full throttle!) As you can imagine if I was to set my ramp rate to 1.0km/h/s and do a pull in 4th gear at full load, that would be EXTREMELY high load, and way beyond what most cars could ever do. That's simulating a hill so steep that your Z (or whichever car) will only accelerate 1km/h every second, at full throttle in 4th gear... To put it another way, imagine a hill so steep that your car has a 0-60mph time of somewhere around 2 minutes. Like I said, more load than you can ever see on the street. So I would attribute your problem to the operator, though he may not be aware there is a problem. Often you'll go with your gut instincts for ramp rate, and sometimes they are just wrong. Let him know what's happening, and he should be able to ensure it doesn't happen again. (and maybe he'll throw in a cheap/free retune) Faster ramp rates are used for more powerful cars, lower ramp rates for slower cars... they should simulate worst case road conditions to be ultimately safe on the street. I guess the answer to both the last 2 posts is that it depends how the operator is loading the car.

One thing that could be the problem is that it can be very hard to hear detonation in the dyno cell depending how it is layed out, it is easier to hear on the street in the car at times. A very sensitive dyno will be able to show you detonation on the graphs no problem. It is possible on most load control dynos to up the load to a point way beyond what you will see on the street, but again that comes down to the dyno operator. Ramp rates, gear selection, intertia settings, etc all play a role in how much load you put on the car. There is a lot of operator control, and as a result room for human error in the process. As a guideline I would recommend you look for tuners that have at least attended Ben Strader's EFI 101 course. It's not a foolproof guide, but it at least shows some interest on their part in professional development, and should mean they have the basic skill set in order to properly tune a car. As for the 1/4 mile stuff Jersey, I honestly have no idea. I don't have a 1/4 mile track anywhere near me, so don't get a ton of customers that have time slips for comparison purposes.

Not entirely following your question Bernardd... do you mean that you were able to put more load on your car on the street, and the dyno tune that was done wasn't safe for the street ie: not enough fuel/too aggressive timing?

Looks like Dynojet finally released their eddy current system in November 2005. For YEARS they advertised it without selling or having more than one working unit, but looks like they've got it working and they can finally step up now. From what I've read though it still won't give you real time HP & Torque numbers when loading, just load cell torque. Still a step in the right direction... Moby - I haven't used a dynapak but did a lot of research before buying mine. They are a really quality unit, take a little longer to setup and from what I remember they are a little more expensive as well. Added costs and setup time without any extra features or quality were enough that I didn't bother. Good units though! You've got to be kidding me. Don't even start this **** in this thread.

Ask dynojet how many load control units they've sold and are being used... they've always advertised it as an option. It just doesn't work.

The mustang had some sort of fuel programmer, though I can't recall which one at the moment. 240sx couldn't be tuned in stock form, so we just show the exhaust gains. Most likely had he spent his money on some parts to make his car tunable, he would have had greater gains for less money. Fuel management should be high on anyones priority list if they plan on modifying a car. Most people think it's not necessary, and that bolt on parts will take them where they want to go.... often not the case.

Yes it is DOS, and there is a good reason for this though it doesn't have the slick interface that it otherwise could. I have been told (but never confirmed) that the sampling rate when logging in a DOS operation is faster and more consistant than what it would be in a windows environment. Makes some sort of freakish sense to me, as you can still buy high end laboratory datalogging software that runs in DOS for some reason. As I said there are some small advantages to letting your car cool a bit after some hard running. A) it is EASY to push the car harder on the dyno than it will ever see on any road or track even with 42,000cfm of cooling it isn't always enough with high strung turbocharged cars, being pounded on run after run C) In stand alone applications you can see how your airflow enrichment curve is reacting, whether it is accurate, or not. Stinky, I would buy this machine again and again given the option. It is well worth nearly 3x the price tag of a dynojet if you plan on using it to TUNE. If you just want a cash cow that spits out dyno baselines, get a dynojet or dynocom. Your profits from the machine will be higher. However, don't underestimate how much you can learn from a good dyno, how much credibility it adds to your shop, and how the excellent results will keep people coming back to you for more purchases and tuning. Light load - Never even thought about it before honestly. It's always done everything I needed to, so I've never pushed the limits. Lower load is pretty easy to tune in general, just lean things out a bunch. But it has always held any rpm I've tried, even quite low. HP Numbers DD vs. Dynojet - Awesome question. Remember when I said your numbers are only as accurate as your operator? Here is why. I have what we call the 'X' button. (surprisingly, all you have to do to activate the X button is hit the x on the keyboard on the bar screen) X is a standard muliplier, that you can make anything you want. A bit more history/explaination here. Dynojets read high. The problem is the faster you spin that big drum, the easier it becomes to spin, and the less power that it takes to spin it. Dynojets are the industry standard because they are A) cheap have been around quite a long time and C) make money. So as a result, probably 75% of dynos out there are dynojets, which read high. As a result, peoples percieved power levels have shifted, what used to be a faster 400hp car is now a fast 475hp car. (for example, don't use those numbers as gospel) Throw the internet into the mix and everyone is reading dynojet numbers, because people brag about those numbers, because those numbers are higher than on other dynos. (most people given the choice tend to think whatever dyno reads highest for their car is the most accurrate one, go figure) So the DD unit reads lower than a dynojet. Honestly we were so dead set against compensating for this, until it actually started costing us business. (people didn't understand, even with the explaination) A pure business decision was that we raise our power output readings by 17% (X=1.17) to correspond with dynojet numbers, and other DD operators in the general area. Am I happy about that? No. But with a $65,000 machine sitting there, even baselines are important when it comes time to make the monthly payment. Now that we've done it, I don't really have a problem anymore with doing it. All you can do is educate people as to why absolute numbers don't mean diddly, if they refuse to listen to you, so be it. But as a business owner I also want them to leave happy, while maintaining my own credibility. Now I educate my customers telling them why this machine reads high like a dynojet. Still being honest, just from a different angle. Customers seem happier with that approach.

Good questions for sure: 1. Cooling: I have 3 (yes, three) 14,000 CFM industrial fans at my shop, that move some serious air. A total of 42,000CFM if required. If your dyno facility doesn't take their fan situation seriously, you should be alarmed. A household fan is not sufficient! (don't laugh, I've seen it) Small squirrel cage fans that move a decent amount of air at a high velocity seem to work pretty well too. A rule of thumb, if it looks like your facility has spent less than $500 on fans, they are not serious about keeping your car cool. There are always power losses as an engine gets too hot... just the way it goes. Sometimes we'll stop for 5 minutes with the fans on and the car idling to keep things in check. You can get a good idea of how much temperature is effecting power this way. You also tend to find out how good the temperature compensation of the EFI system is as well during this time. 2. Each load point: Usually I don't tune each load point, but it depends on the car and EFI system. If someone wants a balls out, perfectly tuned car I could go point by point and tune each one. Otherwise what I do is do some baselines at various loads/rpms and use that info to blend a map together. From there you can move on to tuning specific common points, like highway cruising, idle and 90-100% throttle. The law of diminishing returns applies, I can spend 20 hours tuning an EFI system to the absolute maximum power everywhere, or I can spend 2 hours getting 90% of that power. Most people opt for the 2 hour procedure. 3. I always start tuning with a visual/mechanical inspection of the car, followed by a baseline pull at full throttle. Usually I like to do the full throttle tuning first, the customer is more excited about it, and it's usually as good a starting point as anywhere. Our dyno is sensitive enough that it is very easy to pick up detonation. We watch AFR's and the HP curve very closely looking for lean conditions and/or power spikes that indicate detonation. Definately the first tuning step is to richen up everything to 11.0:1 or so and grandually lean things out to what is still a safe point. Personally I like to start with AFR tuning before timing as it gives more peace of mind knowing that the AFR's are in the safe zone. There will be some back and forth sometimes between AFR and timing, as small gains are made. For our machine, finding optimal timing is easy. Pick a cell to tune, pick amount of load I want to hold the car at, and adjust timing at that load and speed until I get the maximum HP or tractive effort, without detonation issues. Usually I blend the curves afterwards rather than doing that at every load point.

Disclaimer: Results ARE typical. For those that don't know I own a shop with a Dyno Dynamics Dynomometer. There are certain myths about tuning that I'd like to dispell, and would be happy to answer questions specifically related to dynos and what they can and can't do well. Dyno Rates (using mine as an example) If you live in an area with many dyno's you might find cheaper rates. These rates are in canadian dollars. Baseline testing (3 runs): $89.99 Dyno Tuning : $149.99/hour Full Day rental : $799.99/8 hours There is a leaded fuel surcharge. (damages the O2 sensor) These rates reflect the cost of our dyno, which is one of the more expensive ones out there. We are the only game in town, so we are probably slightly higher than what you guys in automotive hotbeds would see. NEVER EVER EVER pay $150/hr to tune on a dynojet... Nothing against dynojet, they brought dyno tuning to the masses, but it just doesn't have the capabilities to properly tune anything but WOT, and even there it isn't the best. I'd recommend dyno dynamics, dynapak, mustang... O2 sensors We include a AFR reading with all these runs, some places will charge extra for that service, as the O2 sensors are a consumable. (at about $400 a pop for ours in particular) For this reason most places will charge additionally for the use of leaded fuel as well. We use an Autronic wideband, without going into detail it is a very, very good, laboratory quality test instrument. The cost of the unit is in line with that, at between $4000-$5000. LM-1's are great for what they are, but be aware that they do have limitations as a result of their low cost. Horsepower Numbers OK, a big one here. I see disappointment all the time because people see big horsepower numbers on some internet forum and don’t really understand what it is that they are looking at. I will try to explain enough that you can intelligently compare numbers. First off, any number spit out by a dyno is completely uncomparible to a number given by another machine. Period. In about 1 second I can vary the output readings of my machine by more than 200%, and other machines are no different. What this means is that I can take a 100rwhp car, measure it at that, then dyno the same car immediately and have it read 200rwhp. Then I can do it again and have it read 20rwhp. Is the dyno wrong? No. The numbers are only as good as your operator. For the most part most dyno shops will keep their machine on the same settings, so that you can use their machine over and over again to compare your gains. It is to their advantage to be consistant. But be aware that 200hp on dyno A does not equal 200hp on dyno B. The point is, you should only be comparing against numbers from the same shop. Peak horsepower numbers: Again, most people make too much out of these. We had a car that made 6whp more after 1.5 hours of tuning and the owner was very disappointed… until he drove the car. With gains of up to 30whp all over the midrange, the car was very, very much faster than before it was tuned. We actually offered to refund his money/undo the tuning, he was so upset with the gains before he drove the car. After we checked back with him he was very apologetic and very, very happy with the results of tuning. Unless you are running a CVT or a super tight ratio gear box, you should pay no attention to your peak number when tuning, and worry much more about the area under your power curve. Gains From Bolting on Parts I see and read about guys spending thousands of dollars on performances parts without ever getting the results they should be able to get from them. Why? Because most people think that tuning is something that can be done by ear in the driveway. It simply can't. You can get the car drivable that way, but you will always have HUGE amounts of power waiting to be unlocked if you think that's all there is to tuning. So if you spend a few grand and just bolt things on, maybe tune by ear, you are looking at this: 1998 240sx - Blitz $$$$ exhaust 1989 Civic GSR Motor - $2000 in bolt on parts 1989 Ford Mustang 5.0 – Heads, headers, etc. Blue graph is the BEFORE mods graph. The LEAST amount of money spent on these 3 cars for these gains was about $800. Gains From Tuning? So what happens if you actually "buck up" and pay for some tuning on a quality machine? I've got results like this coming out the wazoo, but here are some that were allready hosted. 2002 Acura RSX – Tuned with VAFCII 1996 Nissan 240sx KA24TURBO – Tuned with SAFCII Same 1989 Civic GSR as above – Gains from Tuning VAFCII 1990 Nissan 300zxTT – Again, SAFC Tuning. This was his low boost setting. 1989 Ford Mustang 5.0 as above – Timing and fuel mods 1984 Mazda RX7 (351W powered) – Timing and Jetting 1992 Lexus SC400 – SAFCII Tuning Probably the most money spent by any of the above graphs for tuning was about $300, or 2 hours. SAFC/VAFC's are a piece of cake to tune, but they are limited and the gains made are not as good as they could be with a full stand alone system. I believe that every person with those gains from tuning would spend that money again in a heartbeat after seeing the results a good machine and tuning session can produce. The point? Spend your money on tuning before trying to throw more money at parts. You'll end up with a faster car and you'll probably save yourself some cash at the same time.

Don't even bother trying to tune on a dyno that doesn't have load holding capabilities. ie: say no to Dynojet. Find a Dyno Dynamics, Dynapak, etc. shop to do it. You'll spend less in the end and have a better product. (these machines making tuning very quick) Biggest bang for the buck on 98% of the cars I get in my shop is tuning. I see guys spending $2000 on their honda for 12whp, convince them there is more power available, have them consider it a waste of money, eventually convince them it's worthwhile and then for $225 we get them another 40whp through tuning.

Red is by far the most difficult colour to photography correctly. That and digital camera white balance is a tricky subject regardless of colour and will influence your reds a great deal as well. But... I really like the paint! Keep us posted with pictures.

65lbs lost and a whole lot better looking! Very nice.

That is funny, isn't it?

Just to throw another angle on this... I've been using a CFDF with 280ft-lbs of torque, have 22,000 miles on it, 3 seasons of autoX and some spirited drag race lauching (no slicks, just R compounds) and it's held up fine so far. I've slipped it, dumped it, broken stub axles, broken half-shafts, etc. No issues. There are plenty of people with failures of the CFDF with much less abuse, from reports here. Perhaps their QC isn't consistant, perhaps its due to break in and installation procedures. Either way, with the response you recieved from SPEC I wouldn't buy one! CF sounds about the same too. So, is ACT the only option? How are Exedy products? What is a guy to do with a powerful L-series? (not that I have one)

Glad you are happy. Before anyone turns this into a SU vs. 4bbl debate, search please.

Look for Jackson or Optrel... I prefer Optrels for the most part.

You won't get 'flashed' if a helmet fails. Even in the off position the helmet is plenty dark enough to keep you safe. Occasionally cheaper ones will fail to turn on which is annoying at worst.

232rwhp, 281ft-lbs. 25-28mpg highway using a stand alone ECU. Probably could get better milage if I tried to.

That's a legitimate mod, and does work on a lot of cars.

over my face

Thumper was driving.