You mapping on v power? Or meth mix

Should of gone for Martyn's 'special' 278 cams ;)

Dropped the car off today to the guys at engine tuner, so hopefully in the next week I'll have the graph and I'll post it up for you guys to see

I just went on there recommendation but if I ever decide to go to a rotated setup I will put some more aggressive cams in there

Just a v power map for now, low and high boost

Just stumbled on this thread.
Any update on yours?

Few things have needed to be done and a few unforseen things have occurred, but when initially started mapping the car was making around 460bhp at 1.5bar on vpower, unsure on torque figures but I presme they would be pretty close to matching, if the car was run at around 1.9bar I presume it would make very close to 500bhp!

adding some meth into the mix to see what it will really do! Either way it' going to be interesting to say the least :lol1:

Ah ok, didn't you have worked heads? Where they ported, 272cams iirc? Rest of valvtrain upgraded to supertch etc? Stock valves or oversized?
Tbh I think all that counts if you had.
Would be interesting to see the actual spec of rcm's spec c test car which made 528 or something

I've got avcs large port heads, 272 gt spec cams, ported and polished heads with super tech valves standard size ( wish I went for oversized valves now though )

I think the cr will count too tbh, and maybe 278s :D but tbh I think you should run it at least 1.8 bar and see what it does as that turbo will run that psi comfortably.

Or just push it to 2 bar and stop messing lol.

I was told with performance cams and ported heads the turbo should break the 500 bhp mark

Cr? I'm very curious to see the graph especially the mid range! The car is primarily for track so I was hoping for good responsiveness and as little lag as possible without going twinscroll. In the future maybe a year or 2 I will go for a rotated gt30, Owen developments are doing some nice units at the moment and I may get the head reworked and fully spec'd :)

as for the mapping side I'll leave that down the Martyn as I have no clue :lol1:

Lol, compression ratio aka squish, yes it looses me too but it gives the builder to decide on how he wants the motor to be used, i.e. Hard track work, most hp output, low down spool, then he can decide on what components to use.
I get lost by that too but it's a factor what the rally guys use on a small turbo etc.

From what I've seen the PT is not on boost till 4.5k+, some cases 5k, think a well mapped and good built will be around 4.2k I think I've seen, but then for usage of car is deciding on how much power band you have before torque starts to fall, not always about redlining to end as there could be no torque left.

Hence I'm sticking with a small turbo to benefit as much power band as possible while maintaining decent spool.

As a rough example on this graph, let's say it's on full boost by 4K and drops at 6k, then there's only 2k worth of power band there. But it will drive differently and it will be a nice feeling when it's on power lol. The bigger turbo you go, the better headwork and cams you want to reap that extra powerband
That's my logic anyway.

https://cimg5.ibsrv.net/gimg/www.sco...a968fb031d.png

So here are my results.
 

https://cimg7.ibsrv.net/gimg/www.sco...8e204eb625.jpgLow boost 0.9/1bar
https://cimg8.ibsrv.net/gimg/www.sco...e14b642ab1.jpgHigh boost V power 1.4bar
https://cimg4.ibsrv.net/gimg/www.sco...6ee5aa9242.jpgV power + 20%meth 1.6bar

So the 2.35 spools it better and makes the power with less boost but the limit seems to be 470/480 with just v power on this turbo.

I don' think the turbo is quite big enough for the 2.35 to be able to push most boost through it.

I collected the car yesterday and my first impression are that the car is seriously quick! But most of the the power delivery is very smooth! I do think though that the end game is going to be a rotated setup and to go looking for 550bhp on v power alone! But for the time being I'm just going to enjoy the car :lol1:

Yep, that's the case for most of the people :(

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there is very good standard position turbos out there that make that kind of power fairly easy so rotated just seems like extra costs :thumb:

mine made 530 on v-power (1.75bar) and is standard position and still has more in it , the same company also sells bigger ones in standard position spmplently of choice for 550 in standard position

Block and gearbox casing will need grinding a bit to fit the PT

So if the ceiling seems to be 470/480 for these turbos is it not just worth while going for a sc46 or mdx555 450 specced turbo with less lag?

Been debating this for a week... Finally ruled one turbo out.

Just updating my results with this turbo, with some map tweaks and new induction kit we have managed to get 493.9 bhp on Tesco 99 😁

Thanks to enginetuner for working so hard to get this results for me.

https://cimg2.ibsrv.net/gimg/www.sco...ddf548f15e.jpg

What was your final spec in the end Nez? I'm getting my 2.1 built soon with this turbo to go with it. Sounds as though head work/cams is required to break 500.

Just came across this thread which makes for good reading!

Bought one of these turbos yesterday from MB Developments so looking forward to seeing what it can do for me.
RCM Fully Forged EJ257 Block
Blob STI AVCS Heads
RCM Headers and harvey up-pipe
Full exhaust
RCM 340 Fuel Pump
750cc injectors
STI Carberry ECU

That's just some of the bits but you get the idea. Was going to max out a td-05 20g to see what it could do for fun but then this turbo came available and looked too good to miss out on.

Any further suggestions from anyone?