Archive for the ‘AA Sport’ Category

Thursday, October 3rd, 2013
Our test mule awaiting some modifications

Our test mule awaiting some modifications

The following article has been written by Applied Autosport for Practical Perfromance Car magazine 

 

There’s a well established phrase that goes something like ‘Money makes the world go around’. In the car tuning industry bullshit proves a fairly powerful force too. Everyone always wants more for less, and there’s plenty of companies out there that’ll offer you just that. It’s easy to claim you’ll get mega bangs for your bucks, and much harder to disprove for sure that you won‘t. Seeing as so much happens on the internet these days companies on the other side of the world can claim what they like, show you a rolling road print out and take your hard earned money off you. It’s hard to know if you’re being ripped off or not.

 

Cyberspace is littered with dubious products that promise to make your car into a Koenigsegg Killer for the cost of a chicken biryani.  Sometimes the ‘scientific’ explanations for how the product works sound more like a shampoo advert than proper technical engineering. Sometimes they seem plausible. Each car is different but there are some regular offenders that crop up on forums. We need to put them to the test and see what difference they really make.

 

The Mule

 

Our test car is a good old Mazda MX5. After 19 years of being sniggered at for being a hairdressers car it’s clocked up about 90 thousand miles. The engine is the 1.6 version and is completely standard in every respect. The car was filled with a tank of the cheapest supermarket petrol and went to Aldon Automotives rolling road (01384 572553) for a power run as our base setting. The car started life with a quoted power figure of 115bhp. Amazingly the rolling road says we still have 114bhp at the flywheel, and 110lb/ft of torque. That’s a good starting point so the car headed back to base for some modification.

The MX5 has it's performance gains measured at Aldon Automotives rolling road

The MX5 has it’s performance gains measured at Aldon Automotives rolling road

The Products

 

Exhaust-

 

Hidden in among the well established ‘suck, squeeze, bang, blow’ four stroke cycle is another part of the combustion process. It tucks itself in while ‘blow’ is still blowing and when ‘suck’ starts sucking. It’s called a scavenge period. Basically the exhaust and inlet valves are open at the same time as the cams ‘overlap’. As the exhaust charge rushes out the momentum of the gas helps suck the fresh inlet gases in. Exhaust tuning is intended to optimise the scavenge period of the engine. This means getting the exhaust gases away from the engine quickly but also making the natural pulse in the exhaust gases work to help suck the inlet gases into the combustion chamber faster.

 

Tuning methods and designs are massively varied between cars with only turbo cars almost universally needing a simple big exhaust pipe.  Having said that there is some element of truth behind the boy racers belief in a noisy exhaust. If done sensibly then a nice free flowing exhaust should normally release a few bhp. Removing the cat can also sometimes help, especially on these early 90’s cars. As time has gone by car designers have got pretty good at accounting for the effect of a cat on the engine’s gas flow. De-catting a modern car isn’t always such an advantage. Our new exhaust system is simple. Remove the cat, replace the back box with a straight through type and fit a big shiny tip to finish the look. The result sounds like it’s worth about 20bhp. Performance wise it’s the sort of thing you’d probably end up with if you bought of the internet. The internet one will probably look a bit shinier though.

 

 

Our hastily made straight through back box

Our hastily made straight through back box

Inlet-

 

If a free flowing exhaust helps the gases get out of the engine something will be needed to help the air get in faster. The obvious choice is a nice big cone filter. The theory is simple, get more air in by putting less of a restriction in the way. Cheapo versions are available for just a few pounds on good old eBay, although there’s no guarantee they’ll flow better than a standard filter. Most are easily adapted to screw straight onto the cars standard inlet tract in place of the airbox. That normally leaves the air filter sitting close to the engine in the toasty warm engine bay, sucking in dollops of hot air. A pretty retarded thing to do as cold air is more dense than hot air. Therefore you might actually get more air into the engine keeping the air cold than by increasing the air filter size. The added roar from the inlet sounds like it’s worth at least another 5bhp, although we might find we’ll lose 5bhp instead. To help the induction out we’ve got another ingenious device.

 

The electric turbo once fitted

The electric turbo once fitted

This product is the electric super charger. It’s a fan assembly that sits between the air filter and inlet tract. A switch turns the fan on as you open the throttle and the inlet charge is blasted with waves of ‘high pressure’ air. The electric super turbo power blasting air charger promises returns of up to 25 percent power gains. Added to our exhaust and air filter we should in theory be heading for about 180bhp by now.

 

this ebay sourced 'electric turbo' promises big gains

this ebay sourced ‘electric turbo’ promises big gains

 

 

Ignition-

 

With the inlet and exhaust sorted we need to turn our attention to the spark. The standard HT leads looked ripe for an upgrade and a stronger spark would surely help with power. Anyone who wears Burberry and spends their evenings at McDonalds will know that blue HT leads will give more torque, whereas red HT leads will give more power. Our possible power figure is already growing so we opted for blue HT leads to help raise the torque curve. The truth of the matter is that on a high performance engine, running a performance ignition set up it would be necessary to upgrade the HT leads. That would ensure the spark charge doesn’t degrade between the coil and the spark plug. High compression engines such as those with turbos give the spark a hard time. Magnecor leads are perfect for this application. They are some of the best on the market and we are in no way knocking them or their product. They work fantastically when used in the right context. On a standard engine it remains to be seen if they can make any difference.

Silicone HT leads fitted

Silicone HT leads fitted

 

Fuel-

 

That leaves us with only one area left on which to improve. Fuel. There are all sorts of fuel additives but the ones that promise more power are the ones that boost your octane rating. Petrol is complicated stuff but put simply the octane rating shows the fuel resistance to detonation. In other words it will burn in a more controlled manor rather than explode. A fuel that burns in a controlled manor allows for more timing advance to be used without causing detonation (or ‘pinking’). The more timing advance you can run the more power you’ll get. That’s handy if you’re mapping your car to an aftermarket ecu, or if you’re having your petrol car remapped as they could give it a little more ignition advance. If you’re still on good old fashioned points you can give the dizzy a twist and get more power from your octane boosting fuel additive. Very modern cars with learning ecu’s have built in knock sensors. These will control the ignition advance automatically and by boosting the octane rating the car will (over time) give you more power as well. But on a car like this, can you get more power by simply wanging a jug full of octane boost in with the fuel? It’s time to take our budget modifications back to the Aldons rolling road to see what changes we’ve made.

 

The Results

 

The first power run back at Aldons was with the free flowing exhaust and cone air filter in place. The electric super charger was fitted but switched off. The power figure came back at 116bhp, with the torque staying about the same at 110 lb/ft. So that’s an improvement of 2bhp, and the air filter was sitting right next to the exhaust. A proper cold air feed would help even more. Time to unleash the electric super turbo power blasting air charger and see if we get our 25 percent power gains.

 

Much to our surprise with the electric supercharger on power rose to 119bhp and the torque went up too. We had assumed this was just a piece of junk as there’s no way an electric fan can move enough air to positively charge the inlet of an engine. Amazed by the results we decided to take a power run with the supercharger removed altogether. The air filter was connected straight to the inlet tract, still sitting very close to the exhaust. The following power run revealed the mystery.

 

120bhp with the charger removed. It had been restricting the inlet with it switched off, and restricting it less with it switched on. That’s why we’d seen a power gain. To see the true power gains from the exhaust and air filter alone the supercharger went in the bin. That meant our inlet and exhaust modifications had netted 6bhp. The peak torque figured remained the same but the torque curve was improved slightly.

 

With the engine breathing properly the HT leads went on. The power run showed no difference at 120bhp. With other changes these leads would be of use but a standard coil and standard plugs being run by standard management on a standard engine only needs standard leads. Power gains- 0bhp.

 

Finally there’s the fuel additive. Remember the car is only on supermarket fuel which is classified as 95RON (research octane number). We added some of Aldons octane booster fuel additive. The amount added should easily turn our supermarket fuel into an match for Shell V power’s 99 RON. The newly boosted fuel was run through the system for a short while then another power run confirmed the difference made by the fuel alone on a car of this type. Bugger all. The power figure still sat staunchly at 120bhp although the torque had edged up a little to 112 lb/ft and came in a little earlier in the rev range.

 

As we mentioned before, increasing the fuels octane rating is only any use if you can increase either the boost pressure in a turbo car or advance the timing in a normally aspirated car. As luck would have it the timing can be manually advanced on these little MX5s. Roger the rolling road man at Aldons broke out the spanners and started tweaking. With an extra 4 degrees of timing advance the power figures finally started to climb again to 121bhp, and a gain in torque to 114 lb/ft. With the octane booster working to keep the engine safe the timing was advanced further to 6 degrees. Now the power hiked to 123bhp and 122lb/ft of torque. That’s a total gain of 9bhp and 12 lb/ft of torque.

 

The Conclusion

 

Having only spent a few quid on some pretty basic tuning the power gains aren’t bad. Certainly more than I would have expected. However, as the great philosopher and engineer ‘Scotty’ from Star Trek once said, ‘you canne change the laws of physics, Jim’. If you’re surfing on line for a part for your car and the power claims sound too good to be true, they probably are. Just nailing a part on your car rarely works without setting it up properly. An air filter will need cold air feeds, fuel additives will need timing adjustments. And electric super chargers will need throwing in the bin.

 

 

 

 

 

low rider

Friday, October 5th, 2012

This classic cortina gets used in the occasional hillclimb and sprint event, which having worked on it is very brave of the owner. These things are worth a bob or two and he’s a brave man throwing it around a track. Especially considering he restored it from a basket case by himself. All we had to do on this one was get him some more ground clearance. The exhaust had been custom built elsewhere but it didn’t really fit his needs. The car is lower than standard and the exhaust scraped in various places. We reused a large amount of what was already there but with a few changes we tucked the exhaust away. There was so much extra clearance that we were able to lower the engine slightly which will help the cars handling. If I had a car this valuable and I was throwing about on a race track I’d want the handling to be perfect!

Schumacher drops in

Tuesday, August 14th, 2012

Michael Schumacher dropped by with his F1 car recently so we could give it a service and do the tracking. We Wish! This is our F1 simulator and show car which is normally out and about at shows. the transporter had to go for repairs so the car lived in the corner of the garage for a few days. It just looks so cool we had to put a picture of it on the blog.

Capri Development

Tuesday, August 14th, 2012

The AA Sport/AA Silencers Capri race car continues to be developed in between other commitments. The latest development is with the rear axle location. These bars reduce both axle tramp and lateral movement. An added advantage is that by moving the pickup points we’ve been able to change the roll axis of the car and hopefully improve the handling. More testing is required but it looks good so far

Alfa update

Tuesday, August 14th, 2012

we’ve been working on this Alfa for quite a while now. One things had lead to many more and a set of carbs that had been refurbished turned out to be faulty. To remove the problem once and for all the owner had us fit this tasty set of Jenvey throttle bodies and full Canems management. The car is back on the rolling road at the moment and hopefully will reward the owner with some pleasant power figures

MX5 at the rolling road

Tuesday, August 14th, 2012

The MX5 we’ve been building for Practical Performance Car went to the rolling road recently. We can’t give too much away as you’ll have to read the magazine for details, but the car made over 180 bhp!

Mazda MX for practical perfromace car magazineMX5 on the rolling road

Robin Returns

Tuesday, August 14th, 2012

After test runs at Santa Pod the Robin hit the track at Mallory Park. With it’s suspension upgrades the grip was so good we upped the boost and timing slightly for more power. About 3 laps later the headgasket blew, it was fairly inevitable. After the Nissan Deltawing was so successful in this years Le Mans we opted to take the Robin project to the next level. The Robin already uses many similar principals to the Deltawing but until now has used a different concept for weight distribution. The whole car is coming apart again to have a massive rearward shift designed into the weight balance. The engine will get more power and better cooling. nissan deltawing at lemans

custom throttle body manifold

bike throttle bodies on our manifold for the Reliant head

 

Reliant Robin track day car

At Mallory Park

 

ensuring engine is level

Relocating the reliant enginebike throttle bodies on our manifold for the Reliant headAt Mallory Park

It’s what we do- excerpt from an article for Practical Performance Car magazine

Friday, April 27th, 2012

It’s strange that the first question people ask when they’re checking out modified cars is often ‘How much power has it got?’ It’s all well and good being able to say it’s got 400 bhp, but how much weight is that power having to shift? If the car weighs two tonnes then you’ve only got 200 bhp per tonne, which is suddenly less impressive. That’s only equal to a 100 bhp engine in a 500 kg car. The thing is if you tell people you’ve only got 100 bhp they’ll snigger and walk away. ‘Pfff, my Mom’s Corsa has got more power than that’. The conversation’s over before anyone mentions weight.

 

Weight goes far beyond the simple bhp/tonne figure though. Bigger engines will often produce more than enough power to compensate for their extra weight. Carrying a hoofing great engine around does nothing for the handling though. The overall weight of a car will make a huge difference to how it accelerates, brakes and turns into a corner. The distribution of the weight in the car is just as important and can be used to either tune or ruin the handling characteristics.

 

It’s fairly obvious that having a light car means you can accelerate and brake faster, there’s less weight to move around. But just as important is how the weight is spread out across the cars tyres. Each tyre is actually holding up a different weight. In most road cars with the engine up front, the front tyres are holding up a lot more weight than the rears. Likewise with only the driver in, the off side tyres are carrying more weight than the nearside. Amongst other things, the amount of weight (or down force) a tyre has on it will dictate how much grip it can produce, up to a point. From that you could think a heavier car could corner faster. The problem is that the cars weight also acts sideways in a corner and it takes some of the available grip of the tyre and pulls it sideways, causing the tyre to ‘scrub‘. All tyres scrub sideways when turning, it’s known as the slip angle.  Push the slip angle too far and you’re sliding, push the slide too far and you’re spinning. Heavier cars increase slip angles faster than light ones so they run out of grip faster.

To help ensure each tyre is carrying an equal load to start with, cars can be corner weighted. That involves raising the spring heights so more load goes onto the corners where there was less. Unless you have a very well balanced car the weight distribution will always be biased in one direction or another, but it helps to spread the cars weight as evenly as possible. This means each tyre is doing it’s fair share of clinging your car to the road. Corner weighting a car doesn’t necessarily move the weight distribution in the car, it just alters how the car’s suspension supports it.

 

Of course all that talk of spreading the weight out on the tyres is massively over simplified. There’s so many other factors influencing how the car’s suspension behaves, and all we’ve considered so far is how the weight is supported across the four corners. We should also spare a thought for where the weight is in the car. Rather than just say the car has weight, the weight distribution around the car can all be added up and said to have a centre of gravity. It’s basically the balance point for all the weight in the car. If the car was hung from a rope attached at the centre of gravity it would always be balanced. The centre of gravity also has a height within the car. The higher the centre of gravity the more a car will lean as it corners. It leans, or rolls because opposing forces act on the centre of gravity as you corner. It’s those forces you can feel when you are pushed out of your seat as the car brakes or corners. This is called weight transfer. The more it rolls during a corner the more it takes load off the inside tyres reducing the overall grip available to the car.

The centre of gravity rolls around a pivot point called its roll centre, which is set by the cars suspension pick up points. Unless you’re planning on moving the suspension pick up points the best way to reduce the amount of roll a car has is make it lighter and get the weight as low down in the car as possible. Stiffer suspension springs will resist body roll. Generally you’ll always want the softest springs possible for traction but stiff enough to stop too much weight transfer. Assuming your tyres are up to the job of transmitting the load then sometimes a bit more weight transfer in a straight line (pitch) helps push them into the road surface and get more grip. For example if you have a rear wheel drive car with the engine at the front you’ll need a bit of weight transfer to get the driving tyres to grip properly. Generally though too much weight transfer reduces grip and ruins the balance in the car, especially during cornering (roll). It’s that balance that everyone’s trying to find when they set a car up. How much weight your car has and where it’s distributed will affect how much weight transfer you have, how much work your suspension is having to do and so how hard you can push your tyres when accelerating, braking and cornering. Performance driving techniques are all developed around shifting the balance around the tyres to get the best grip for the longest time. It’s all of these factors and more that we focus on when developing a car, and it’s driver.

The Pig flies again

Friday, April 27th, 2012

Our very own Reliant Robin, or the Flying Pig as it’s become known, took to the strip at Santa Pod recently. This was just a test run for the newly turbo charged engine. We fitted the turbo to blow through the standard carb with a few modifications. The test ran well although it was on very low boost so the car is now ready for Practical Performance Car magazines show at Mallory Park. The Robin draws a crowd wherever it goes and is a challenge to drive. We wanted to build a car to prove we can make anything handle. With a modified double wishbone front suspension set up it corners and brakes as it should now. It just goes to prove anything is possible. Check it out on our you tube channel at http://www.youtube.com/watch?v=n3exKXBlqFY

MX5 Hillclimb car

Friday, April 27th, 2012

We’ve been building this hillclimb car for Practical Performance Car Magazine. The full details of the build will be available to read over the next few months. PPC mag have an event called the 999 challenge. The idea is to build the best MoT passable car you can for 999 quid and carry out  a timed quarter mile and handling course. The fastest car wins. We decided to take the concept a step further and see if we could build a hill climb car for full competition still sticking to the 999 pound budget. The list of modifications is massive. We reduced the weight by about 20% which is hard going on a car that’s so light to start with. With all the weight stripped out we built a cage that not only keeps the driver safe but adds to the shells rigidity. The engine received a turbo and anti lag system including launch control and flat shift. It also features a hydrogen gas system for better combustion and a cold water spray for the intercooler. We carried out a few suspension and brake modifications and thoroughly set the cars geometry to give it perfect handling. The aerodynamics were last to be addressed and are controlled tightly by the regulations. We designed an aero package that other than the allowed rear spoiler didn’t change the cars silhouette. We achieved this with a flat underfloor, undercut splitter and a rear diffuser than uses a cut out into the rear bumper. The rear aero is fed by the exhaust gases between the spoiler and the diffuser which aid flow attachment. There’s still some fine tuning to be done but it should be an awesome package on a very tight budget