Am I right to be skeptical about tuning?

[cleverusername]

Basically this come up on another forum, where posts are convinced they can get extra power by bolting on a bigger throttle body, performance air filter and porting a head.

Now I have my doubts. I am not saying you can't get more power from engine with a remap, difference cam and a well planned rebuild. I just have my doubts about DIY modifications to cylinderheads, bolting on bigger carbs, bigger throttle bodies and performance air filters.

One poster says they tested their setup on a dyno and got an extra 10hp after their upgrades. Now It occurred to me that some of his power gains could simply be down to the fact he had replaced dirty airfilter with a clean one. That you could easily get 10hp extra out of an old engine by simply giving it a good service.

As for porting and polishing. I studied civil engineering at Uni, so I had to do a bit of fluid mechanics. What I learnt was fluid mechanics is extremely complicated and trying to working out gas flow is no simple task. The gas flow in a cylinder head will be affected by the shape of the ports, so I suspect it is a bit more complicated than make ports wider and polish.

So am I right to doubt the world of tuning on the cheap or does it actually work?

[sprint95m]

Now I have my doubts. I am saying you can't get more power from engine with a remap, difference cam and a well planned rebuild.

Yes you can.



By the way, that is not how to spell sceptical.



Ian.

[dollyman]

You can get get a lot more power with a remap (done by an expert) but simply adding bits on rarely works and is usually not cost effective as for porting and polishing it is a waste of time on a road car as it means one hell of a lot of work to get it right, as you have to match the manifold to the head or you just create turbulence which will slow slow it down.
A pal has had his Peugeot 307 1.6hdi remapped..... and it absolutely flies and is better on fuel, but he did have the innards of his dpf removed (illegal i know) but it still pass's the mot emmisions better than previous.
To gain 10hp though? Why bother you would barely notice it. Sounds like a barstool mechanic to me

Tony.

[cleverusername]

Now I have my doubts. I am saying you can't get more power from engine with a remap, difference cam and a well planned rebuild.

Yes you can.



By the way, that is not how to spell sceptical.



Ian.

Yeah there is a typo there, it should say " I am not saying you can't get more power from engine with a remap, difference cam and a well planned rebuild."

Thanks for spotting it, I will fix the original post.

[cleverusername]

You can get get a lot more power with a remap (done by an expert) but simply adding bits on rarely works and is usually not cost effective as for porting and polishing it is a waste of time on a road car as it means one hell of a lot of work to get it right, as you have to match the manifold to the head or you just create turbulence which will slow slow it down.
A pal has had his Peugeot 307 1.6hdi remapped..... and it absolutely flies and is better on fuel, but he did have the innards of his dpf removed (illegal i know) but it still pass's the mot emmisions better than previous.
To gain 10hp though? Why bother you would barely notice it. Sounds like a barstool mechanic to me

Tony.

Well he apparently paid for it to be tested before and after, which must have cost him a bit.

As for a remap, I know it can give you extra power, there was a typo in my original post. I have 75 Diesel as an everyday car and my father also has one. Mine is the 130 version and his is the 115. The only different is the map the engine has, everything else is identical.

[Carledo]

In the days when "our" cars were made, you could make from 5 - 20bhp just by "blueprinting" your engine, which is to say you were just eliminating manufacturing tolerances. The reason for the variation being that some engines were built naturally better than others.

We've all had cars that went better than the norm for no apparent reason, this is it! (I've also seen more than a few that were naturally awful, thirsty underperformers!)

Nowadays manufacturing tolerances are much tighter, gasflow is better understood and modern cars with ECU controlled Ei and EFi are much more tightly controlled for maximum efficiency in both power and economy. So they are relatively MUCH more difficult to extract those few extra horses from, especially for very little outlay beyond a bit of hard graft. But modern engines are SO much better than the stuff we mess with, that they are artificially detuned by the manufacturers map, for example, you can get a PD engined Golf diesel which produces anything from 99ps, all the way to 170ps and the only difference is the map! So a remap on a modern is the best way to go, if fact it's the ONLY way to go without spending huge amounts of dosh to end up with a massively powerful but temperamental and unreliable beast.

The aftermarket tuning industry grew massively from it's beginnings in the early 60s and is still huge today, you'd think THAT many people COULDN'T be wrong! But it's a sad fact that many hundreds of times more pounds have been put in than horsepower have been pulled out! The usual result of 60s and 70s "tuning" was only more noise, less mpg and an empty wallet!

This is the "Weber effect" People have been plonking Weber carbs on cars since I was a kid and mistaking a nice induction roar for horsepower! Why not, when the adverts told you it was so?

But an engine is an homogenised, symbiotic whole, more than the sum of it's parts, if you mess with one part, you MUST mess with all of it. To make the most of those twin Webers we all love, you need a different cam, exhaust, distributor, bigger valves, head work, port matching, etc. Then to prevent the motor self destructing under the strain of all the extra horses, you need to stiffen up the bottom end of the engine, better bearings, finer balance, improved oil circulation, cooling and so on. It's never ending really and VERY expensive!

THIS is why I decided, long ago, that tuning was a mugs game and the cheapest way to get more horsepower, was to import a larger and more powerful motor from a different car! It's the American method, "there ain't no substitute for cubes" (meaning cubic inches, the US capacity measure) It's worked for them for a lot of years and it works for me! Nowadays it's enough to fit a modern EFi motor of a similar capacity to get a large gain in RWHP aaaaaaand better fuel economy! "Greener" too with lower emissions and using recycled parts!

So IMO, yes, unless its been done properly (and very expensively) you ARE right to be a bit sceptical about tuning!

Steve

[cleverusername]

Yes but to be fair Steve, what you do isn't for the amateur mechanic. The first problem is making sure your new engine will fit. If I tried it i would guarantee that I would foul on something. Then you have the problems of welding up new mounts and weight distribution. That is before you get to electronics.

As you say, one of the reason modern engines are more efficient is they are covered in sensors and have engine management systems. So you have to somehow replicate all that in your build. Assuming it is even possible to get your donor engine to work when it parted form the electronics in the donor car.

So I am impressed by your builds but I alas I think something like that would be beyond my abilities.

Have you though about getting electric with one your builds? That seems to be the latest thing.

[RobSun]

You can get get a lot more power with a remap (done by an expert) but simply adding bits on rarely works and is usually not cost effective as for porting and polishing it is a waste of time on a road car as it means one hell of a lot of work to get it right, as you have to match the manifold to the head or you just create turbulence which will slow slow it down.
A pal has had his Peugeot 307 1.6hdi remapped..... and it absolutely flies and is better on fuel, but he did have the innards of his dpf removed (illegal i know) but it still pass's the mot emmisions better than previous.
To gain 10hp though? Why bother you would barely notice it. Sounds like a barstool mechanic to me

Tony.

Well he apparently paid for it to be tested before and after, which must have cost him a bit.

As for a remap, I know it can give you extra power, there was a typo in my original post. I have 75 Diesel as an everyday car and my father also has one. Mine is the 130 version and his is the 115. The only different is the map the engine has, everything else is identical.

Get a 160 remap from one of the 75 club guru's and you will see even better performance and fuel economy. The BMW engine is able to give a lot more and safely if you take it to an expert like Big Russ who was one of the developers.

[RobSun]

On modern engines some remaps like the one I mentioned earlier for the Rover 75/ZTs is doable because BMW didn't want this range to have more power than the parent companies models which put out 160 BHP. Other remaps offered for other makes have often shown to be a con when tested,

Older cars from the 60s onwards can be modified easily for more power if done correctly but at a cost. I took part in Gp. 1 rallying and these cars were standard but blue printed. Lots of parts were needed to do this to find the "best" ones to build an engine that would give the most, so manufacturer or main dealer back up was required.

Other cars were very much modified with manifolds, cams, porting and polishing, electric fans, carbs, gear boxes, diffs, all costing many pennies and with varying results but did increase power and performance. Porting and polishing to match up the inlet and exhaust manifolds, get rid of usually very poor lumpy rough finish in the head castings to a smooth matt finish with each port and chamber balanced for volume, bigger valves, worked for not much cash but lots of effort done properly. I enjoyed doing it, then a good cam for the type of performance needed, some made cars undrivable for everyday use, and carbs changed, jetted, set up properly, lightened and balanced bottom end etc would make a big difference. Now with a modern engine its not needed, just think how much a new engine puts out. When all the above was done it was unlikely we got out as much power as a modern family car with a similar size engine, but in the day we could improve them simply because the manufacturing standards and costings left the engines less efficient.

[Carledo]

Yes but to be fair Steve, what you do isn't for the amateur mechanic. The first problem is making sure your new engine will fit. If I tried it i would guarantee that I would foul on something. Then you have the problems of welding up new mounts and weight distribution. That is before you get to electronics.

As you say, one of the reason modern engines are more efficient is they are covered in sensors and have engine management systems. So you have to somehow replicate all that in your build. Assuming it is even possible to get your donor engine to work when it parted form the electronics in the donor car.

So I am impressed by your builds but I alas I think something like that would be beyond my abilities.

Have you though about getting electric with one your builds? That seems to be the latest thing.

Yes and no! I'm pioneering a lot on my conversions, but what i've done can be copied much easier as you KNOW it will work in the end! Welding up mounts is no different to welding up sills, it's just welding! Weight distribution is just a matter of playing with spring rates, adjustable shox will and does mostly fix that. Electrically and electronically the Dolomega was a bit of a challenge, but the Carledo was simplicity itself to wire up, needing only 5 connections making from it's discrete management loom to make it run! I ALWAYS use the factory management that goes with the engine else otherwise most of the efficiency gains are lost. It took me the best part of 2 years to build the Carledo, working as and when and around work and other commitments, but I reckon, with all the bits in hand (and I know exactly WHAT bits I need now) I could build another in not much more than a fortnight's concentrated work. In fact I have ALMOST a complete kit of bits to build another "Carledo" or "Carlomite" on hand and may well build it into a car (yet to be bought) as a retirement project to sell on for profit.

A properly sorted hi-po tuned standard motor would take at least as long and cost much more!

As to going electric, don't talk dirty! I'd rather shove wasps up my a**e! Battery/Electric is not and probably never will be the answer to the worlds transport energy and pollution problems, at best it's a stopgap. Hydrogen is a much better alternative, but getting the infrastructure to supply it is much more problematic. If they solve that, i'd be first in line to build a Hydrogen fueled Dolomite! I've given a little thought to the idea of a petrol/electric hybrid where the electric alone drives the vehicle and the petrol engine ONLY charges the batteries. This means the weight of batteries needing to be carried is reduced and you aren't carrying around 2 separate drivetrains. Also the ICE can be smaller and run at a constant (most efficient) RPM. This could give up to around 100mpg real world gas mileage and still give the stunning performance that electric motor drive is capable of. I really think this COULD work, but the worlds governments are so anti anything even remotely fossil fueled, however economical, that no work is being done to develop it.

Steve

[Jod Clark]

If anyone can give me some real world facts regarding how a remap can enable an engine to produce more power from less fuel I would be delighted to hear it.

Perhaps the remap increases the energy density of the fuel?
Or maybe the remap somehow has a means of altering the laws of physics?

[dollyman]

You are getting it wrong Jod. The mapping makes it go like stink when you want it to, driving at normal speeds it makes them more economical Nothing else.

Tony,

[James467]

I have a MK5 Golf GTI with the VW 2.0 TFSI engine (used in a lot of VW group cars), stock it produced 200ish bhp, actually mine actually produced 204 bhp (with 85k on the clock) when dyno'd before I had it remapped.

After removing the pre cat (not illegal), a service, Audi S4 Intercooler, pipercross panel air filter and a full tank of VPower (these engines don't like running 95 RON) it has been remapped by R Tech and now produces 256bhp. On a long run I now get around 35-40 mpg at 70-80mph compared to around 32-35 previously, depending on traffic and my right foot! The car weighs approx, 1300 or so kilos.

With a larger K04 Turbo, different exhaust, injectors, HPFP from an Audi RS4, different air filter and another remap they can be made to produce a reliable 345 - 380bhp, depending what engine internals you have they will take up to 550 but the reliability drops off.

So yes, modern cars do have a lot of scope for tuning, but you need to know what you are doing.

http://r-techperformance.co.uk/2-0-tfsi-tuning/

[sprint95m]

Hydrogen is a much better alternative, but getting the infrastructure to supply it is much more problematic. If they solve that, i'd be first in line to build a Hydrogen fueled Dolomite!
Steve

As we speak Orkney Islands Council is developing not just hydrogen powered road going vehicles
but also passenger/freight ferries and furthermore an Orcadian company is building a hydrogen powered passenger plane.

Orkney, of course, has a massive surplus of renewables' electricity to use....



Ian.

[Bumpa]

As we speak Orkney Islands Council is developing not just hydrogen powered road going vehicles
but also passenger/freight ferries and furthermore an Orcadian company is building a hydrogen powered passenger plane.

Orkney, of course, has a massive surplus of renewables' electricity to use....

Ian.

There have been a couple of hydrogen fuel cell buses in daily use in Aberdeen for a few years now. The issue is making the hydrogen in an energy efficient way, and setting up a distribution network. Other than that, the H2 fuel cell car is the perfect solution. The only emission is water, the range is about 300 miles and it only takes 5 minutes to refuel. What's not to like?