Hi Comp pistons without remap

[mikekean]

I need to build a new engine for my cup racer due to the engine failing last month. Im going to have a head built by CNC heads with 1 piece valves, I also want to fit forged rods and pistons with a 12.6:1 CR. But i cant stretch to a new ECU and ITB's at current so the idea is to run with standard cams on the Cup racer ECU. But will I be able to run with the increased compressions safely without a remap?

I run 98 Ron fuel always, i could just run the new head on a standard bottom end but really i just want to build the motor all in one go so it's done and i dont have to mess about building a new bottom end at a later date. Then when I have the money I can just fit a set of cams and ITB's and run the 220hp i want.

Cheers

Mike

 

[Chip-mk1]

I would imagine the cup racer ECU is mapped quite aggressively on the ignition side of things in order to make the cars as lively as possible, so I would expect you to have detonation problems if you increase the CR by over 10% and dont r****d the timing.

 

[Silent_Scone]

I'm fairly sure your ignition table will need tampering with or you'll be detting like a champ, if you're contemplating actually racing without getting the map checked personally I wouldn't even dare try but that's just more out of scared ignorance lol. One of the profs will give you a more definitive answer though

 

[MicKPM]

Don't do it - just save for an ECU and/or remap or else those pistons won't last.

I'm personally using a DTA S40 Pro as its cheap as chips and does just what it's supposed to without any bells or whistles. You're kinda limited as you have VVC which my unit won't run so have to take this in to consideration (if you wish to continue running it of course) but there's loads out there for decent money that will suit your needs.

 

[Chip-mk1]

Don't do it - just save for an ECU and/or remap or else those pistons won't last.

I'm personally using a DTA S40 Pro as its cheap as chips and does just what it's supposed to without any bells or whistles. You're kinda limited as you have VVC which my unit won't run so have to take this in to consideration (if you wish to continue running it of course) but there's loads out there for decent money that will suit your needs.

Its only an on/off state on the Mk2 dephasor, so the DTA S40 should do that just fine mate, just hook it upto Aux 2.

Failing that, you could just do it on an RPM window switch and a TPS switch as an entirely external controller for it, its VERY basic, literally just a case of give it 12V live with ignition switch and then earth it and it advances, pull the earth off and it retards again.

 

[mikekean]

Looks like i will just be fitting the head on a standard bottom end then, i take it the ported head will be fine with the standard map? Cheers for the advice guys.

 

[Chip-mk1]

Looks like i will just be fitting the head on a standard bottom end then, i take it the ported head will be fine with the standard map? Cheers for the advice guys.

If the ported head makes any positive difference to airflow for the same manifold pressure, then it means that your engine will run leaner as a result of fitting it, and hence if it doesnt make the engine run lean, its not worth fitting of course, lol

 

[mikekean]

Surely the ECU will compensate to a certain extent if the lambda isn't seeing the right AFR?

 

[Chip-mk1]

Surely the ECU will compensate to a certain extent if the lambda isn't seeing the right AFR?

At parts throttle yes so your economy going to the shops and back will be ok but not at full throttle as its a narrowband sensor.
given your car is a racecar though I figured we were only interested in the full throttle risk of melting the engine so hence my reply.

 

[MicKPM]

My S40 is running a single TOCA spec throttle on an F7R Chip so its not a huge issue but I've never looked at it potentially running an F4R... DTA tech support is a good as always so when you ask a question, the normal answer is "read the manual... If it says it can it will, if it don't it can't"

Thanks for the heads up though, might be worth trying to bell it up on one.

Mick

 

[Chip-mk1]

RTFM, lol

 

[Dan@SJM]

Thats better than Omex. Their 600 manual states if you want Launch control and Wideband support contact OMEX. you contact Omex, and they say no.

 

[MicKPM]

Somedays though I can sympathise because they must get some proper stupid questions/customers... Saying "RTFM" is a simple but perfect solution to most queries I guess.

 

[Cr33do]

Is the cup racer ECU locked or is it funds (or waste of) that are preventing a remap? If it the later surely you will waste a certain amount of money rebuilding the engine for a second time when you eventually go hi-comp? I havent got a clue about building engines but I would rather get top and bottom built once, remap it to suit, then add itb's later.

 

[BIGASH]

Cup racer ECU's are locked unfortunately and I don't think they can be un locked like the grp n ecu's

 

[BIGASH]

Mike I know it is still 1k but have you seen that K-Tec have created a Gen90 with interface that connects into the standard dash and wiring loom on the cup racer? I'm not a fan of the way they have wired it but it's a good solution and would just be plug and play instead of having to do new loom, dash and ECU

 

[MicKPM]

Good point James but isn't it like £1300?

 

[BIGASH]

Not sure really Mick, I guess it will be around 1k as that's what the normal Gen90 is (I think) and this is just that with a multi connector and a bit of heat shrink

Would be a much cheaper option than new dash, loom, switch panel and ECU I imagine. The only thing that would worry me is the durability of the wiring that I have seen pictures of as there looks to be a lot of strain on some of the cables in the connector

 

[Cr33do]

Cup racer ECU's are locked unfortunately and I don't think they can be un locked like the grp n ecu's

Cheers James. Suppose it makes sense thinking about it

 

[BIGASH]

This is a picture of the K-tec ecu and connector

 

[Andrewclio]

This is what I'm looking to do, I've just purchased a cup racer loom to go with the sequential, could this sort of interface between cup racer loom and ecu be made for any ecu?

 

[Chip-mk1]

Yes, or you could just create a new loom.

 

[Dan519]

In theory you can do it with anything. First challenge is finding the loom plugs and wiring schemes. Second challenge is getting things to communicate. K-tec have even got the Marelli dash running from the GEN90, which is no mean feat

 

[mikekean]

Very interesting regarding the Gen90. pretty trick what Ktec have done getting everything to work. But I was just going to chop the plug off my engine loom and wire in a DTA S60 when I eventually do go that route, probably with a different dash to as the cup racer one has limited features and no back light.

My main issue is living in jersey we don't have any mappers over here so getting it done is a trip to the uk. So in reality it's all or nothing, just stay standard or shell out 5-6k on a new engine, ECU and ITB's. a lot of money for 50hp. Not so bad over a couple of years but all in one go is hard to swallow.

 

[Dan519]

I looked into a DTA a lot a while back. Just can't get over the software looking like it was written for a sinclair 64

 

[Dan@SJM]

^ they've still not updated it then! I had a play around with DTA's software a few years back and it gave me a headache. Tbh mapping interface wise, Mtec/megasquirts software is probably the best looking/most user friendly out there, map3000 isn't far behind it. Chip showed me the Autronic software a few weeks ago while we were fettling with his mk1, and I must say it was impressive, but not overly user friendly in terms of being able to just pick it up and away you go without reading the manual.

 

[Dan519]

map3000 is ok, I've used it for years and got quite used to it. GWV4 is much more modern and when you know it is a lot better. Live scope tracing of lambda for tweaking accel fuel is a personal favourite function.

I really like the interface on the canems software too TBH, basic though it is in it's current form. It's very much like a simpler map3000

MS software is meh. last time I looked it didn't even have live sensor feedback data.

 

[Dan@SJM]

If its different software to mtec's then I can't comment, however the Mtec software chip has has all the live data feedback which is nice.

 

[Chip-mk1]

I looked into a DTA a lot a while back. Just can't get over the software looking like it was written for a sinclair 64

The s40 onwards stuff is a lot better than the old p8 pro, that felt out of date even when I first started using it and that was best part of a decade ago now!
Emerald is definitely the worst of the current ecu's on the market software wise.

 

[Silent_Scone]

Map3000 is good because it's easy to navigate, even I could use it lol.

 

[Chip-mk1]

Map3000 is good because it's easy to navigate, even I could use it lol.

I cant think of any mapping software that is particuarly hard to navigate TBH, even the emerald its pretty easy to see the main tables etc.

Mapping isnt about knowing the software though, its about knowing the engine, actually putting the numbers in is a piece of cake, its knowing what the numbers should be that needs experience.

 

[MicKPM]

To me its Witchcraft... I can get an engine to run but that's all... Drive on a trailer and then off to a professional lol