DS3 155 I like to change to about 270hp

[cyclone]

Ah my friend but people who are into modifying their engine to make a Lot more hp will have at least heard of those things at some point. And having heard or read of it somewhere they can then research and delve into subject for details on how all that stuff could further their quest.

[Superfly Guy]

Ah my friend but people who are into modifying their engine to make a Lot more hp will have at least heard of those things at some point. And having heard or read of it somewhere they can then research and delve into subject for details on how all that stuff could further their quest.

Why is everyone just looking at the Turbo, exhaust, (dump valve) aftermarket intercooler and then a re-map ?

They may well do but this forum is for DS3 owners not specifically those into modding engines, as above, 'everyone'.

For the majority, the most cost-effective return is where we go first, time/power/cost = a map, after that its diminishing returns for the same three factors. If after a map, exhaust, air filter blah blah blah its onto elseware to move the bottleneck. Air, fuel, combustion coming in, gearbox and clutch in the middle and power to the wheels going out, there will always be a bottleneck, its how much time anybody wants to devote to moving and minimising that bottleneck for an acceptable return.

More importantly, does Bill drive a DS3? If so what would he do?

[Czar]

So are you saying purely efficiency improvements like (and my experience comes from playing Gran Turismo ) internal polishing or things like increasing the bore size or lighter pistons etc (again I'm dragging back memories of the above mentioned legendary game).

Your on the money with polishing, and port polishing only has benefits in dry intakes, otherwise know nowadays as, direct injection engines, (GDI) polishing the ports of a regular wet port injection engine has no benefit whatsoever, in fact it actually causes negative gain, due to the fuel/air tumble mix separation, and the lossof intake velocity, resulting in performance loss.

Purely concentrating on the cylinder head for now.

I'm starting to wonder if Czar is actually an expert on these engines or if his forté is in cryptography

LOL, not so much cryptography, simply trying to promote questions, from which everyone will have a better understanding.

jeez come on. stuff like port matching, porting the head, camshaft, bigger valves, multi angle valve jobs, stronger valve springs to keep the valves closed in high rpm high boost. The normal high performance head stuff.

Pretty much, although the valve size is almost maxed out, from the factory, I only managed a very marginal oversize valve, both inlet and exhaust, less than 1mm for each, yes the oversize did have better flow, it wasn't until the very high RPM that any significant gain was measured.

But not everybody who joins a specific car forum knows that, in fact very very few would.
I drop my car a Jamies, he does some magic, I get it back with a significant boost in power for not a lot of (relative) cash, that's what most people are happy with.

Very true, that said, I think it's good to promote thought from questions, so everyone can understand what has long been considered the Black art of engine performance, sadly if engineers like myself don't try to unlock the Black art doors, the Black art will eventually be lost, to the bolt on only and remap brigade, and that would be a real shame, in my humble opinion.

[Jimbob]

Oh it was much easier in my day. You took the engine out of your Ford Anglia and dropped a Ford Granada engine in. Job done!

JB

[cyclone]

They may well do but this forum is for DS3 owners not specifically those into modding engines, as above, 'everyone'.

For the majority, the most cost-effective return is where we go first, time/power/cost = a map, after that its diminishing returns for the same three factors. If after a map, exhaust, air filter blah blah blah its onto elseware to move the bottleneck. Air, fuel, combustion coming in, gearbox and clutch in the middle and power to the wheels going out, there will always be a bottleneck, its how much time anybody wants to devote to moving and minimising that bottleneck for an acceptable return.



More importantly, does Bill drive a DS3? If so what would he do?

I think you should go back and read the thread title again 270 is not a small number, so not your average DS3 driver.

[Czar]

Oh it was much easier in my day. You took the engine out of your Ford Anglia and dropped a Ford Granada engine in. Job done!

JB

This was sooooooo true, engine swaps were done in the home garage, over the space of the weekend, and much fun was had on the roads too, I miss those days.

[cyclone]

your both making me miss my 1969 AMX

[Chris_Blue]

You know anything about the THP engine in the new DS 3 Performance edition Czar?

[Czar]

You know anything about the THP engine in the new DS 3 Performance edition Czar?

I've not seen the new DS3 edition, that said, I probably do, what would you like to know ?

[Jimbob]

This was sooooooo true, engine swaps were done in the home garage, over the space of the weekend, and much fun was had on the roads too, I miss those days.

You had room to stand in the bonnet whilst pulling the engine out! The hardest part was balancing the twin carbs - I used to use a stethoscope

JB

[Chris_Blue]

I've not seen the new DS3 edition, that said, I probably do, what would you like to know ?

Bearing in mind the 200bhp DS3 Racing engine had many breakages, and total losses as reported on here, arising from Shattered pistons in the main, but also the dreaded carbonisation and PCV issues, wondered if they had reviewed and overhauled the engine.

Even the THP 150 and 155 didn't have anywhere near the same amount of piston and engine total failure issues, and was predominantly only the inlet valve carbonisation that cased the issues there, other than the knackered timing gear in the early days.

I put the differences in quality down to power output increase

Or is it the exact same engine. Realise it is the same base lump

Have they changed bore slightly, piston rings/ piston composite, injectors upgraded, PCV altered etc etc

[Czar]

Bearing in mind the 200bhp DS3 Racing engine had many breakages, and total losses as reported on here, arising from Shattered pistons in the main, but also the dreaded carbonisation and PCV issues, wondered if they had reviewed and overhauled the engine.

Even the THP 150 and 155 didn't have anywhere near the same amount of piston and engine total failure issues, and was predominantly only the inlet valve carbonisation that cased the issues there, other than the knackered timing gear in the early days.

I put the differences in quality down to power output increase

Or is it the exact same engine. Realise it is the same base lump

Have they changed bore slightly, piston rings/ piston composite, injectors upgraded, PCV altered etc etc

I have mentioned this before, it is NOT the engine, the power output, or indeed inferior components, the majority of the engine failures are indeed from very poor ECU program parameter maps, especially in the Citroen and Peugeot vehicles which use the PSA developed THP engine.

The bore/stroke will be exactly the same 85.8mm stroke 77mm bore 1598cc the cylinder head will be the significant change, variable timing and lift on the inlet camshaft with just variable timing on the exhaust camshaft, developed by BMW sold on licence to PSA, the PCV although redesigned, simply extends the time period before any significant carbon build up becomes an issue, it still will be an issue as the cars age, however, with very careful ECU timing phase parameter programming, this is the key to help reduce carbon build up, hope this helps answer some of your questions.

[Shiro]

The old DS3 Racing Engine was some kind of a hybrid. On the one hand the engine had the "big" K04 Turbo on the other hand the block and head were from the small THP150. The new DS3 Performance will have the drivetrain from the 208 GTI 30th Edition. So it's a real THP200 and not just a THP150 with a big turbo on it

[Czar]

The old DS3 Racing Engine was some kind of a hybrid. On the one hand the engine had the "big" K04 Turbo on the other hand the block and head were from the small THP150. The new DS3 Performance will have the drivetrain from the 208 GTI 30th Edition. So it's a real THP200 and not just a THP150 with a big turbo on it

The engine has never ever been any kind of hybrid, nor has the Citroen DS3 Racing THP come fitted with the KO4 turbocharger from the factory, the factory standard chosen turbocharger was the KO3

[Chris_Blue]

Lets hope the pistons hold up- specially number 4 (Was it?)