Big Uno's R26 Project / Engine Build

Thank you guys!!!

We did talk about cam gains, if you can potentially add the effective of 20hp to the power as the engine where naturally aspirated it will be that plus that multiplied by that by bar (boost)
So in theory if I could raise its power by 20hp I would gain around 50hp @ 1.5bar.
So even a small gain from cams can be a larger gain at the top end, with a likely sacrifice to bottom end power and spooling time.

Yes I am really happy, will be looking at putting a larger fuel pump in the tank next I think. But having now mashed the throttle a bit I dont think I will be bored of the power... until winter anyway

 

Bring a lid, and spare pair of pants

 

Were not doing the Rugby gp dont get any ideas

 

I seem to be playing a game of musical regulator recently, anyway here is where it is now fitted

Had some fairly large changes to the fuel system since the car was mapped.

Since we woke the turbo up engine bay temperatures have been ripping and so have fuel temperatures too...
After a fairly short time of giving it some boost it was quite apparent something would need to be done... at times even misfiring on load due to what I believe to be vaporised fuel in the lines.

One of the fundemental problems with the Megane fuel system is where the lines run, as you have seen I have fitted a rail return, but both lines run in the original place... behind the turbo...
I think its fairly expected the engine would get hot, and with my tubular manifold and collector that sits right infront of the fuel lines and seperated only by the OE heatshield, heat transfer was way too high.
I have been considering cooling the fuel but first I think its more important to remove the hot spots and fix the issue instead of masking it.

So I have ripped out both fuel lines completely, and moved everything over to the cooler side of the bay, I was hoping to run the lines below the car as they where, but crossing the exhaust was a problem, and there was no nice way to swap sides.
My lines now run through the car and up through the bulkhead. Really wanted to avoid running the lines internally, afterall it is a road going car, and the lines below helps with cooling. But this is the best solution for now I think.

The engine running seems to now be completely fixed and the fuel is massively cooler.

The next problem I seem to be having is the rear gear linkage is coming off, seems to be due to heat. It is the rear outer retainer part that fixes to the U shape bracket on the box. The white retaining pin seems to have lost its spring and doesnt retain for long fairly sure this may be due to heat.
Has anyone got any fixes for this?

 

Unfortunately I have had to decide on selling the car, I have had a lot of good and bad times building it, and hope to carry on with another at a later date.

I have posted a quick sale thread up here; http://rsmegane.com/threads/megane-r26-430hp-£13k-o-n-o.17208/

Really hope if a sale does go through it will be to an enthusiast here.

For now I will still be continuing work on the car, and still be posting progress! I want it to be in its best possible shape for a sale and there are still some areas that need my attention

 

Needs must unfortunately mate

 

Depends what you want? Engine, gearbox and turbo? car comes free.

 

Small update, not had much spare time for car stuff over the last few weeks, but have made a few small changes.

Quite soon following mapping, I had some issues with ignition, as I mentioned before there was missfiring at high rpm on load.
This has now been fixed by a simple coil pack change. Now running Valeo green tops and had no problems whatsoever. The other ones seem to have been damaged by the heat, sometimes you get what you pay for
All 4 coil pack retaining bolts are now helicoiled too.

I have also fitted a turbo blanket, this has dropped engine bay temps dramatically! Doesnt look great, but it does work well.



I also had a request for some data on the cars drivability. But thought I would post it up as I am sure others might be interested too.

The first video is from a standstill, and shows the pull on WOT from around 3500rpm in second and through third.
Struggling to get the power on the floor at the top end of second, some wider and better tyres would help.



Second video shows a couple of different pulls, different rpm ranges in different gears.



Both videos taken on private circuit... of course.

Thought I would include intake temperature, ambient was varying between 18 - 20 centrigrade where I was driving. It shows how well the intercooler is working.

There is also fairly minimal lag from the G25, you will see it holds well above 3500rpm. The Turbosmart gen5 is also doing a great job at maintaining pressure.

As you can see the difference between a stock or stage 1 engine to this are quite large it is a handful. Did get into 5th at low rpm towards the end of the video but I think its second, third and fourth people want to see. By the redline in 4th you are already getting a serious lick on at around 130mph.

 

Yes there is no doubt the G25 spool time is considerably faster, would be interesting if we both did some pulls from say the same rpm at full throttle in the same gear?
I think at higher rpm the 3071 will be almost as responsive. It looks like the 25 output is also considerably higher at lower rpm too. Its quite interesting, I would say the stats given by Garrett are correct.

What power are you making now? And what cams & compression are you running?

My limiter is my cams, but I dont think 430 is bad with stock cams at 1.5bar, I dont see a need to run higher boost than what I am as the turbo is currently efficient and I wouldnt want to drop my compression. I think with some more duration and overlap mine could see 470+ at the same boost.

 

Thats enough power I think you would benifit most from more lower end power if you can keep the top end the same. Do you have graphs from power runs would be interesting to see the two turbos compared.

I can see about doing some pulls tomorrow for you!

 

Great stuff stradman, yes I am making power and torque considerably sooner, I re-attached both our graphs below to show the differences more clearly.
The main difference here is the spooling time, mine is around 1000rpm sooner, of course giving the early power delivery. Although your power is being delivered very well going by the graph. This is really interesting comparing data.

I would imagine Chris limited your torque, I asked to keep mine down, as I like the gearbox working the way it is although my clutch is rated for more than the 360ftlb I am running.

I am guessing given the figures we have a very similar set up other than the turbo? 870cc injectors, stock cams, stock compression? I would be interested to see your setup, what wastegate are you using also? Did he give you a boost plot? I suspect you are running slightly more boost than me, around 10% more?

 

Really quite low boost, was expecting stock cams with the power figure as close to mine I am guessing you could make more power if you wanted! do you find you are also coming off boost around tighter tracks often? Looks like it is doing ok at Donnington but that is quite fast as a car track. Sounds like it goes well

 

Hey fellas, sorry for the inactivity! Ians right, and matt put in a link above to Simons follow on thread!

Hope you are doing OK Ian? How did you find the Megane?? Did tell you its goes well!