What makes an engine "tuneable"?

[thecremeegg]

I've always wondered about this,what exactly makes the engines of say an EVO more "tuneable" than say a 182? Is it the components used? the construction techniques?

Any answers appreciated

Tom

 

[Ross M]

for a start an evo is a turbo and the 182 n/a

 

[Jamie]

Generally forced induction engines have far more potential for engine gains. In theory with an unlimited budget any engine has realisitc potential for good power gains but its generally turbo engines which are tuneable as there is a mix between good gains and ease of extraction.

 

[thecremeegg]

for a start an evo is a turbo and the 182 n/a

I was just using 182 as an example.I could have said mini cooper or something lol

 

[Vincec79]

Depends on what you mean by tuneable really...

Most people say turbo engines are more tuneable as simple stuff such as a remap greatly increase the power in comparison with their NA equivalents.

It is beneficial to have solid, reliable blocks as a basis to work from. Internal components such as pistons tend to be replaced when increasing the power significantly ie fitting turbos on NA cars or fitting larger turbos.

Jap stuff tends to be a lot more tuneable per say as they have a much larger modifyng industry just look at all the specialist manuifacturers such as HKS, Spoon, Greddy, Blitz etc, where as try and think of european equivalents that don't make just generic parts

 

[G_F]

Induction, how its combusted and exited, forged internals etc

 

[Ross M]

for example .... 2.0 182 bhp Clio 182 vrs 1.6 159bhp Civic VTI

the clio is less tuneable than the civic ...

 

[BenR]

Its ability to process air and the design characteristics that are favourable in this.

 

[trile]

for example .... 2.0 182 bhp Clio 182 vrs 1.6 159bhp Civic VTI

the clio is less tuneable than the civic ...

why ? they both have ..erm..similar valve timing "thingy" ! :S

 

[Ja5on]

u could go on and on discussing why. but tbh honest its to do with huge number of things and how they are made on the production line.

eg some of the bmws etc are limited to 155mph not for the reason of safety but, that is the limit that somt of the componants will take.

The internals of an old teg typr rcan take 400bhp! but for the day to day driver, mogs etc etc it only has 190 or close

 

[BrianR]

Strong block, crank, pistons, liners etc, all the stuff that will break as you increase the strain on components by upping the power output.

 

[edde]

eg some of the bmws etc are limited to 155mph not for the reason of safety but, that is the limit that somt of the componants will take.

The cars were limited to 155 as part of a gentlemans aggreement years ago as cars were getting quicker and quicker and to do there bit for heath and safety they agrrred to limit to that qhich is ample fast enough.

 

[BrianR]

eg some of the bmws etc are limited to 155mph not for the reason of safety but, that is the limit that somt of the componants will take.

The cars were limited to 155 as part of a gentlemans aggreement years ago as cars were getting quicker and quicker and to do there bit for heath and safety they agrrred to limit to that qhich is ample fast enough.

Mostly the Gentleman's agreement went something like this...

Green Party:- "if you don't limit cars to 260kph we will vote against every bill in Parliament"

Hung majority parties in German Government:- "Ja"

Green Party:- "Next topic"

Democracy Eh! cant whack it,

 

[clowo16v]

Turbos are easier to tune up to a certain point but after that point the costs are massive.

A case for that is volvo 940 turbo engines. The standard bottom end is good for 400+bhp. To get that power you need a head of another volvo, a t3/4 hybrid turbo, a big intercooler and megasquirt. You can get 400bhp for lots less than a thousand pounds. If you get bits cheap you could do it for £5-600. The standard drivetrain will cope with that much power.

However if you want to go loads about 400bhp you need new rods, pistons, a GT42 turbo (at least), new subframe, new ARB droplinks, new rear axle etc etc. To build a 600-ish bhp engine costs £4-5k, to make the car handle it costs another £2-3k.

Matt

 

[thecremeegg]

So effectively its down to strength of the components and the capabilities of the turbo?

 

[_Tom]

Turbos are easier to tune up to a certain point but after that point the costs are massive.

But at that point so is a n/a? :S

 

[BenR]

has nothing to do with the strength of components, only its ability to process air........that is all.

 

[BrianR]

Dont agree Ben,

I know its too old school for you guys, but Bill Nicholson the factory tuner at BMC and MG in the 60s when MGBs and Minis were winning major world rallies and races, was given the 3 bearing crank engines of the time as the basis for his works cars.

By relatively simple tuning, opening the ports, enlarging the valves, raising the compression ratio by skimming the head and changing carburetors for larger capacity ones he could double the power of the engines.

But they became fragile and regularly dropped their bearings or put a rod through the side.
They were regularly thrashed by the Triumph Tr4, which had a 5 bearing crank and block straight out of a Commer lorry. Heavy as lead, but strong

Bill was instrumental in having the BMC A and B Series 5 bearing blocks put into production (this was gp5 days so production profiles) and almost over night he doubled the power again and the reliability with it. And these were still not cross flow 8 port heads and they had cast cranks.

Triumph gave up motor racing after that.

The group N cars where it was body silhouette only required were even more powerful.

My Dad had a Nicholson MGB which had the steel crank 8 port cross flow head and twin Webber Dcoe 40s, it was developed for group N road racing as they called it then (production sports cars)

Really quick car for the day and so reliable the Northamptonshire Police had them as motorway patrol cars and they could out run an E type and still get home for tea and tiffen.

The Hampshire Police had fuel injected Rudspeed Volvo B180s that were supposed to be faster than a Scotsman who's round it was, and they were never out of the workshops having rods popped back in big oily holes, because the block /crank was so weak.
They were fast but you could lose them in a Ford Anglia with a full tank.

 

[BenR]

And everything you have just said leads to one thing.......the amount of air an engine can process.

All the stronger mechanical components are there to support rpm basically, which is what you use in an NA engine to process air.

So, change nothing on the engine bar the mechanical strength of an engine and you will see no gain in power, and typically some losses due to increased parasitic drag.

What your really commenting on is that higher strength components are needed to help produce power through high rpm stability and reliability, but without the ability to process air, namely a good cylinder head........the engine is junk.

Tunability, or the ability to increase power........we all expect to change mechanical components for stronger ones, but the initial cylinder head is where it counts.

So component strength, imo, has nothing to do with tunability.

 

[BrianR]

Ben, I think we are singing off the same Hymn sheet, just a bit out of tune.

The original question was probably sufficiently wide for us both to be right.

Your methodology can not be flawed, but without a strong bottom end, you will still have a problems with broken engines.

The best example of this is the V10 F1 engines where the blocks were shaved so thin to save weight, they were almost transparent. I didn't count the blow ups for those seasons, but there were a lot.

The new V8 formula has moved the goal posts because of the need for the engines to last for more than a practise session or a race with no T car for mistakes.

The teams take the weight penalty in exchange for reliability, and shave it off the car elsewhere.

I don't know if you have ever seen the H16 F1. BRM 1.5 Lr engine (yes 16 cyl 1.5l) or more down to earth the Honda N6oo engine 600 cc 27000 rpm in a family car. How strong were they.

In essence, I think we are both right for different reasons.

 

[Graham Gooch]

No Brian the question is what makes an engine tunable and to me that means extracting power as said but increasing the volumetric efficiency, therefore more processed air ergo more power.

 

[BenR]

Brain, i understand what your saying........but i'm simply saying that component strength has nothing to do with tunability since they all invariably get changed.

Therefore, the only real importance is the cylinder head and valvetrain assembly.........everything else can be accomodated for.

Start off with a s**t head and no matter how much you shave a block or run Ti internals.......it wont make any power, so it has to relevance to tunability.