# RB30 Power/torque guess??



## R32 Combat (Jan 29, 2004)

My car goes for it's first dyno tune on wednesday.:nervous: 

I've no idea what to expect, what do you think?
Running @1bar & 1.2 bar
ATW figs, I'm not interested in flywheel figs.

Here is the spec(bearing in mind I've built/tuned it:nervous: :nervous

RB30
ACL forged pistons
ACL bearings
Re-worked std rods
Balanced std crank
Jun 272deg 10.5 lift cams
Highly ported head
Single 80mm throttle body
800cc injectors
Tomei Fuel rail
HKS intercooler
HKS T51r turbo kit
HKS Hi-Power exhaust
AEM ECU
255 lph pump
Std 95 octane fuel

There are a few other things but there not related to engine performance.

Any guesses??


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## matt j (Oct 19, 2001)

R32 Combat said:


> Any guesses??


Is it a nearest the actual figures wins a prize??? 

A totally *uneducated* guess would be;

ATW figures @1.2Bar
430BHP to 450BHP 
380lb/ft to 400lb/ft

Told you it was a wild guess tho


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## stuartstaples (Nov 14, 2004)

1 bar
410 bhp 370lb ft
1.2 bar
460 bhp 420lb ft
Best of luck Andy. Let me/us know how you get on


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## plkettle (Feb 2, 2004)

1 bar : 400 hp and 460lb/ft
1.2 bar: 440hp and 485lb/ft


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## matt j (Oct 19, 2001)

plkettle said:


> 1 bar : 400 hp and 460lb/ft
> 1.2 bar: 440hp and 485lb/ft


Just a question and I hope nobody minds me asking but;

Even though it's an RB30 will it actually produce more Torque than Power?
Like I said, not wanting to drag this off topic, just a question.

Matt.


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## ollam69 (Jun 22, 2006)

1 bar
459 bhp 420lb ft
1.2 bar
500 bhp 485lb ft and BANG!

Good luck matey


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## [email protected] M/S (Feb 16, 2002)

A T51KAI @ 1.2 bar will run approx 450/480 wheel bhp ( no run down bhp boosting allowed) IMHO. with around 460/480 LB/FT of torque , if it doesnt there is something very wrong.

@ 1.0 bar I would say 380/420 wheel bhp and around 400/420 lb/ft of torque

All I can say is i can guess very very well.....;-)


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## R32 Combat (Jan 29, 2004)

I'm sure you can Mark

If I can hit your 1.2 predictions, I'll be chuffed.


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## TREG (May 20, 2004)

Abbey M/S said:


> A T51KAI @ 1.2 bar will run approx 450/480 wheel bhp ( no run down bhp boosting allowed) IMHO. with around 460/480 LB/FT of torque , if it doesnt there is something very wrong.
> 
> @ 1.0 bar I would say 380/420 wheel bhp and around 400/420 lb/ft of torque
> 
> All I can say is i can guess very very well.....;-)








I would of guessed higher at 1.2 bar, although Im all Torque  :thumbsup:


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## roadie (Feb 6, 2006)

Any reason for the rather low boost pressure(s) other than nervousness ??? (understandably of course). And what peak rpm will you pull out at ??:thumbsup:


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## R32 Combat (Jan 29, 2004)

I don't know the limitations or the fuel pump, thats my main concern. Also, a std gearbox won't last to long with high torque.

I really want 550 lbs/ft(745Nm), but thats alot.

I might up the boost some more and see what happens. 

I only have it set to 1bar, and that feels fast enough. Grip is an issue with the way the power come alive.

7000rpm is my limit, but the dyno figs will say if I need more, which I doubt.


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## Pimpernel (Dec 5, 2003)

Andy, are you really planning on only 95 octane? That's a significant constraint on what you can do with the timing.

The Silver Surfer  is probably in the right ballpark. Although I don't know what the ACL pistons will handle and AEM is akin to using a 186 processor  

The T51 will happily run upto 1.6Bar, especially if you put super unleaded in you tight wad!


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## R32 Combat (Jan 29, 2004)

95 octane is fine, then for extra safely I can run 98.

AEM akin to a 186 processor? They sent man into space with less than that.


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## TREG (May 20, 2004)

R32 Combat said:


> Grip is an issue with the way the power come alive.



What tyres you using to put the power down Andy?


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## R32 Combat (Jan 29, 2004)

Bridgestone Potenza RE55, track tyres.


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## plkettle (Feb 2, 2004)

i have a SX fuel pump and swirlpot setup for sale, would easy do what you need for that amount of torque...550lb/ft !!!! that would feel quite nice :smokin: :smokin: :smokin:


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## R32 Combat (Jan 29, 2004)

I've got to draw the line somewhere on when to stop tuning. And this is it.:bawling:


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## [email protected] M/S (Feb 16, 2002)

> 550lb/ft !!!! that would feel quite nice


It is lovely to have 550lb/ft of torque.......he he he


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## R32 Combat (Jan 29, 2004)

Mark

<a href="http://plugin.smileycentral.com/http%253A%252F%252Fwww.smileycentral.com%252F%253Fpartner%253DZSzeb008%255FZN%2526i%253D36%252F36%255F11%255F22%2526feat%253Dprof/page.html" target="_blank"><img src="http://smileys.smileycentral.com/cat/36/36_11_22.gif" alt="SmileyCentral.com" border="0"><img border="0" src="http://plugin.smileycentral.com/http%253A%252F%252Fimgfarm%252Ecom%252Fimages%252Fnocache%252Ftr%252Ffw%252Fsmiley%252Fsocial%252Egif%253Fi%253D36%252F36_11_22/image.gif"></a>


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## [email protected] M/S (Feb 16, 2002)

HE HE HE HE....your car should be above mine in Torque/bhp as you run the 
T51KAI and I only have a weenie T04Z....but I do have the V-cam kit......I start to pull boost @1200rpm....


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## R32 Combat (Jan 29, 2004)

Yeh, well, so, whats you point. V-cam, thats for girls.uke:


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## [email protected] M/S (Feb 16, 2002)

you saying i am a girl then......


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## R32 Combat (Jan 29, 2004)

Yep. But not to your face.
:flame:


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## chovden (Oct 16, 2003)

And? How did it do?


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## Lamb (Sep 25, 2003)

R32 Combat said:


> Yep. But not to your face.
> 
> PMSL.....what you lot like!
> 
> Where these figures Andy???????


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## Lamb (Sep 25, 2003)

R32 Combat said:


> Yep. But not to your face.
> :flame:



PMSL.....what you lot like!

Where these figures Andy???????[/QUOTE]


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## ChristianR (May 31, 2005)

Abbey M/S said:


> HE HE HE HE....your car should be above mine in Torque/bhp as you run the
> T51KAI and I only have a weenie T04Z....but I do have the V-cam kit......I start to pull boost @1200rpm....



more details! :thumbsup:


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## TREG (May 20, 2004)

The dyno could not cope with the power from Andys car! Mark hid in the toilet untill Andy had left as he was so ashamed of his slow car. :wavey:


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## Snowfiend (Jul 11, 2006)

LOL.....so come on Andy, we're all waiting ?


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## R32 Combat (Jan 29, 2004)

Well, that didn't go according to plan.

The first few runs were to see what the map was like that I'd done. There was a slight miss at 5500rpm. We re-gapped the plugs, Dan played with the coil dwell and that sorted that.

The 1st proper run @ 1bar was 393hp @ 5500rpm and 400lbs/ft @ 5500. There were a few boost issues.

We did a few more runs to sort the boost issue. One run was @ 1.4 bar and that was 560lbs/ft @ the wheels. Quite a good figure.. I can't remember the exact HP, but it was 530ish @ wheels..

Then we noticed the oil breather chuffing a little. D'oh...

We ran a compression check and found that #6 was only 30psi... Oops, I think we broke it... I don't know exactly what happened yet, but the suspicion is that it has pinched the ring slightly due to over heating or its cracked the ring land.

O'well, just another day in skyline ownership. At least I drove it home ok. Albeit, very gingerly..

I just need to tell the wife now.:nervous: 

Still, it look like it has good potential.

And Dan @ Ji_Kan is a top bloke and really knows his stuff. He's given me a few pointers on what to tweek so this doesn't happen again.[sigh]


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## Asim R32GTR (Sep 24, 2003)

R32 Combat said:


> Well, that didn't go according to plan.
> 
> The first few runs were to see what the map was like that I'd done. There was a slight miss at 5500rpm. We re-gapped the plugs, Dan played with the coil dwell and that sorted that.
> 
> ...


Sorry to hear this Andy.
What pistons did you use?

Asim...


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## Scott (Jun 29, 2001)

Andy,

Sorry to read about your problems.   

So is it back out with the spanners then?


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## Snowfiend (Jul 11, 2006)

Oh no, sorry to hear that Andy  

Sounds like I was starting to produce some really nice figures.


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## R32 Combat (Jan 29, 2004)

The pistons are ACL. It's a fair assumption to say heat was the issue. It had run for probably 2 mins flat out before hand.


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## Asim R32GTR (Sep 24, 2003)

R32 Combat said:


> The pistons are ACL. It's a fair assumption to say heat was the issue. It had run for probably 2 mins flat out before hand.


How much ring gap did you have?

I have always used a little more than recomended, just for this same reason.....

Asim...


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## R32 Combat (Jan 29, 2004)

I can't remember what ring gap I have. The block came assembled, although I did re-check everything and clean it again..


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## Peter (Jun 27, 2001)

Bugger, really sorry to hear that Andy... I doubt it's much consolation that it certainly shows outstanding potential but you should take some comfort from that.


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## TREG (May 20, 2004)

Bad luck Andy. But it sounds like once you have cured that problem, you will have a real monster on your hands!


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## Tony G (Jun 2, 2003)

Sorry to hear this Andy, hope it proves not too expensive to fix.



R32 Combat said:


> The pistons are ACL. It's a fair assumption to say heat was the issue. It had run for probably 2 mins flat out before hand.


Is this usual on their dyno? It seems a very long time to be flat out imo.

Tony


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## R32 Combat (Jan 29, 2004)

I don't think it will be expensive, I got some Halfords vouchers for christmas so I'll shop there for spares....


We did do lots of runs, probably 15 or so. Usually they wouldn't be done in such quick succession, but it took a while for Dan so find out where I'd gone wrong with the boost control.


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## rockabilly (Oct 15, 2003)

bad news andy. i know what its like to rebuild. hope you get it sorted mate..


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## Tony G (Jun 2, 2003)

What bore size Andy? I may know of a couple of new ACL 87MM pistons if you need to swap just one or two. PM me with details if I can help mate.

Tony


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## RSAndy (Jul 10, 2006)

sorry to hear of ya engines probs Andy, saw you on the way home from nightshift this morning driving down Lower way, give me a shout if you need it trailering anywhere to get it fixed.

Andy


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## R32 Combat (Jan 29, 2004)

They are 86.5mm pistons. 

RSAndy, Thanks for the offer. I'll probably be working from home. Feel free to pick up a spanner:thumbsup:


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## phat_gadgy (Jan 23, 2005)

Feel for you Andy


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## TREG (May 20, 2004)

R32 Combat said:


> Feel free to pick up a spanner:thumbsup:




Wish I understood engines more, I'd love to help. Love reading your posts Andy, just get abit lost when you get technical.


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## davewilkins (Jun 30, 2001)

Was looking forward to seeing your figures. Sorry to see all did not go well. I am sure you will be back with all running ok soon.
Dave


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## LAURENCE (Jan 4, 2005)

Andy, the weather is still poo out, too wet, there's no way you should be allowed out with 560lb/ft....thats just naughty.
Good luck ironing out the teething problems and making it even stronger mate.


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## TREG (May 20, 2004)

Just out of interest Andy, What stopping power are you using 6 pot??


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## RSAndy (Jul 10, 2006)

he's running fairly standard brakes I think?

Andy, Gis a shout when your whipping it out and I'll pop over, look forwrd to it.


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## R32 Combat (Jan 29, 2004)

Treg, you're nearly right, my current stopping power is a broken sixth pot.

Andy, Sunday hopefully, I'll bell ya..


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## TREG (May 20, 2004)

R32 Combat said:


> Treg, you're nearly right, my current stopping power is a broken sixth pot.
> 
> Andy, Sunday hopefully, I'll bell ya..




Eeeeeek:chuckle:


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## YYY (Jan 6, 2007)

Sorry to hear about your misfortune, after all the hard work and effort.... 

but didnt someone say the limit of an OZ RB is about 50 bhp as they were not designed for race or high pressure use?

Did you use uprated internals?


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## R32 Combat (Jan 29, 2004)

> but didnt someone say the limit of an OZ RB is about 50 bhp as they were not designed for race or high pressure use?


50hp???

Yeh, I used forged pistons. The next ones will be nickle plated on the crowns and around the top edge if all goes to plan.


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## [email protected] M/S (Feb 16, 2002)

LOL...


> but didnt someone say the limit of an OZ RB is about 50 bhp as they were not designed for race or high pressure use?


Yeah right want a ride in mine and mine has only a small turbo.....as per the picture on the left hand side


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## MartinC (Jan 1, 2006)

shame it blew on the dyno, just a reason to come back again stronger and better!!


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## R32 Combat (Jan 29, 2004)

Well, I'm confident it won't happen again.


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## YYY (Jan 6, 2007)

oops typo, I meant 500bh


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## R32 Combat (Jan 29, 2004)

The head came off in 1.5 hours, which is always a bonus.










The bore in #6 is perfect but as assumed, the piston has some signs of DET, the other 5 are perfect.











I guess it could have been worse.

Here's a graph @ 11psi


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## YYY (Jan 6, 2007)

Did adjust the fuel map to make cyl 6 more rich, as its a known weakness of the std plenum design. A nismo one addresses that problem.


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## R32 Combat (Jan 29, 2004)

No, we didn't trim #6 for more fuel, which is bl00dy stupid I know. i was hoping we could detect knock and trim accordingly but it didn't happen that way.


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## Snowfiend (Jul 11, 2006)

Andy - Sorry for the hijack....just trying to improve my knowledge of the engine. Does the RB lump have solid block or liners ? Cant tell from that pic if that's just a raised circle around the edge of the piston crown or if it's a liner.


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## Philip (Jan 17, 2002)

Closed deck, no liners in standard form.

Phil


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## R32 Combat (Jan 29, 2004)

The raised edge is the 'O' ring fitted into the block.


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## [email protected] (Jan 2, 2005)

That looks to me just like what we saw with the AEM boxes at the beginning. They have huge spark scatter running on the nissan cas. What rpms did you turn of sync at ?? To the best of my knoledge the issues are not rectified properly yet either. What type of timing light did you use for setting up the ign ? Did you check for any creep / scatter at hight rpms above sync off.

Robbie


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## R32 Combat (Jan 29, 2004)

Piston 1,2,5 & 6 have det damage. 6 and 2 were pinching the rings. The cause is that the bores are too big for the pistons.


MMMmmmm


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## Tony G (Jun 2, 2003)

Andy dont you mean the bores are too small? At the end of the day if the rings are gapped to the bore this wont change regardless of piston/bore clearance.
Out of interest what were the ring gaps on the top rings?
BTW that is quick head removal mate!!

Tony


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## R32 Combat (Jan 29, 2004)

Being able to remove the head with the manifolds on makes for a quick job.

I've been told that the volume between the crown the the top ring around the piston is too big, allowing for det to occure there.


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## ExScoobyT (Jan 6, 2004)

Still on AEM I assume; sounds exactly like what happened to mine. AEM total pile of crap.....


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## Tony G (Jun 2, 2003)

I've been told that the volume between the crown the the top ring around the piston is too big, allowing for det to occure there.[/QUOTE]


Not convinced about this. When I built GP n scooby engines we used to taper the top of the piston (from the crown to the ring land) to allow the piston to "tip" slightly at tdc without the edge of the piston scuffing on the bore.
I suppose different builders have there different ideas though I have done a similar piston job on a 630hp 2 litre without any det. My theory is to get the squish area sorted first then adjust the compression as required and this yields better anti-det properties.

The ring gap thing could be playing a part too hence me asking about your gaps- too tight, although not necessarily giving nip at the ends, can promote a lot of trapped gas between the ring lands and cause breakage.

Have you got any pistons out yet?

Tony


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## R32 Combat (Jan 29, 2004)

The pistons are out on the bench. I don't know what the ring gaps were, I never gapped them. They came already done.


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## R32 Combat (Jan 29, 2004)

IF it is the AEM, I'll overcome it.


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## ExScoobyT (Jan 6, 2004)

Andy - not really an `If` is it? No product with as many reported issues deserves any kind of `loyalty` (or blinkered acceptance). Why should you have to `overcome` anything on a plug`n`play ECU costing near to top-draw money. Honestly, do yourself a favour (and the engine!!) and go back to the PFC or spend the money and go Motec / Pectel etc.


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## R32 Combat (Jan 29, 2004)

Um, the PFC is no better. I've has probelms with that too.

Are you suggesting that I'm the only one to have det issues? My RB26 ran very will with the AEM. There were no det issues with than one.

I will persevere with what I have. I realise some wouldn't, but thats just me.


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## [email protected] (Jan 2, 2005)

Andy i would say thet the poblem is spark scatter related and the pinching the rings is form severe pre ignition causing huge mechanical stress on the ring lands. This should show up on the big ends alos. The bearings on the pistons that have pinched will show signs of this maybe not to the maked eye but to a good measurment system it will be very easy to spot. 

If you want to email me your map i can have look at a few things in the sync setup. 

Some close up pics of the pistons on the thrust side would be good also.

Robbie


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## R32 Combat (Jan 29, 2004)

I'll post up all the pics tomorrow. My map is in my ECU, which I can't remove cos the car has no battery at the mo, but I can mail an old map.


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## [email protected] (Jan 2, 2005)

Its very hard to detect the type of pre ignition that may have caused your failure as it dosent happed at TDC and cause the piston to give a audible rattle.

Drop me an e-mail [email protected]e


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## ExScoobyT (Jan 6, 2004)

Andy, PFC no better? You are joking surely? I do admire dedication and perserverence but this can become blind stupidity!

Ringland damage due to variable spark timing due to a pile of shite ECU. Why oh why would you want to carry-on with clearly substandard hardware? You don`t have shares in AEM do you? I really truely deeply cannot understand your attitude towards it??!! If theres even a 5% chance of problems why risk a 5K (minimum) engine?


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## YYY (Jan 6, 2007)

AEM is reknowned for having misfire and spark issues. There is a lot said about this on their forums. IMO the PFC is deffo a better way to go, bar HKS F Con or Motec.


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## R32 Combat (Jan 29, 2004)

#2










#6


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## [email protected] (Jan 2, 2005)

Recieved your e-mail andy. When i have my thought togther on it i will e-mail you back. 

The errosion on piston no 6 has been happening over a while i would say.

Robbie


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## R32 Combat (Jan 29, 2004)

I think they have all been slowly sparking away for a while..


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## Asim R32GTR (Sep 24, 2003)

wow... that type of damage doesnt happen on a short dyno session.

Why didnt you use the triggerwheel on the crank that you made?

Asim...


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## R32 Combat (Jan 29, 2004)

Now the engines out, I'll be copying your sensor mount and fitting mine...

I hope I can get to the cause of this problem. It this like the damage you've seen Asim?


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## [email protected] (Jan 2, 2005)

Thats exactly why i returned some 15+ AEM's early last year.

Robbie


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## R32 Combat (Jan 29, 2004)

If this was due to ignition scatter, why would #3/4 be ok and some worse than others? I would have thought that they would all have been the same.


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## ahapartridge (May 19, 2003)

Bad news Andy, any damage to anywhere else?


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## R32 Combat (Jan 29, 2004)

No, that is it. The bores are perfect.


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## [email protected] (Jan 2, 2005)

Beacuse of slight varations in the cas that re occur at the same time every cycle. Also do you know if you have the same afr in every cylinder.


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## ExScoobyT (Jan 6, 2004)

...interesting, my engine failure was No2 & 6 as well. Andy - did you not post a while back with quite different EGT`s across the cyclinders? A good indication of variable timing across the cylinders........(or AFR of course, but gut feeling is timing.....)


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## R32 Combat (Jan 29, 2004)

Thats very interesting that you had #2 & #6 go. It's just still odd that I had exactly the setup on an RB26 block but std pistons and no problems at all.


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## [email protected] M/S (Feb 16, 2002)

Did you pull the pistons from your RB26 to have a look Andy?


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## R32 Combat (Jan 29, 2004)

I pulled #6 before I sold it out of curiosity. There was some very slight damage to the edge, but considering the pounding with novice mapping and 1.5bar, I didn't think it was ocause for any concern.


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## Asim R32GTR (Sep 24, 2003)

R32 Combat said:


> Now the engines out, I'll be copying your sensor mount and fitting mine...
> 
> I hope I can get to the cause of this problem. It this like the damage you've seen Asim?


Hi Andy

Yes it is the same thing i have seen on other RB26 engines + the ringland has been split.

Right now i am sooooo glad i installed a standalone ecu, wich runs of the crank, not the cas. 

Engines does not run 100% smoothly, the bottom end will always have a little affect on the timingbelt, wich in result will make the cas wobble.... and like Robbie says, it will happend at the same cycle every time.

Get the sensor mounted on the crank mate 

Asim..


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## ExScoobyT (Jan 6, 2004)

Nothing wrong with the nissan CAS, assuming the ECU knows what to do with it!!!!!!!


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## Asim R32GTR (Sep 24, 2003)

ExScoobyT said:


> Nothing wrong with the nissan CAS, assuming the ECU knows what to do with it!!!!!!!


Thats is true, there is nothing wrong with the cas itself, but the way it gives the signals to the ecu, when the cambelt if flexing  Or if you have adjustable camsprockets.

in 99% of all aftermarket ecu`s it is recomended to run the trigger off the crank, if you runt it off the cam, there will ALWAYS be a risk for spark scatter....

Asim..


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## whoflungdung (May 7, 2005)

Hi Andy

well as I always say...."new year, same $hit"  
sorry to hear the news, but its not beyond you to fix
has Mark popped out of the toilet yet?  

as Mr Shuffles is almost ready for take two :thumbsup: 
after losing several friends and loads of dosh
its almost ready, so get the chilli on
the bear is on his way.......:nervous:    :squintdan :chuckle:

good luck, see you soon

and you Mark


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## R32 Combat (Jan 29, 2004)

Hi John

Well hurry up and get down here.:wavey: 

I hope you get it sorted soon too. Tis been a while..


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## whoflungdung (May 7, 2005)

R32 Combat said:


> Hi John
> 
> Well hurry up and get down here.:wavey:
> 
> I hope you get it sorted soon too. Tis been a while..


I will bring some extra,extra strong chilli powder with me
Here's a dusty peek at the nuisance........


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## Hugh Keir (Jul 25, 2001)

ExScoobyT said:


> Nothing wrong with the nissan CAS, assuming the ECU knows what to do with it!!!!!!!


Interested to know what any ECU might do with the CAS wobble shown below?










The 0 to 100 on the x axis = 20° CAS variation = around 10° movement in ignition timing on the graph.

The y axis is time.

Interested to hear which ECU could make an improvement on the random nature of the RB 26 readings above?

Cheers

Hugh


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## lightspeed (Jul 11, 2002)

Hugh - is that referenced to a crank pickup signal?

I assume you run crank pickup with the Motec?

I noticed that Autronic sell a new disc to fit the CAS with only 6 +1 slots - anyone tried one?


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## lightspeed (Jul 11, 2002)

[email protected] - did you ever try a crank sensor with an AEM before you gave up with them?


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## R32 Combat (Jan 29, 2004)

http://www.autronic.com/image_files/trigger_disks/nissandisk.jpg


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## [email protected] (Jan 2, 2005)

We did try aem with 36-1 crank triger and they worked alot better but aem kept telling us that that was not nessary.


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## Hugh Keir (Jul 25, 2001)

lightspeed said:


> Hugh - is that referenced to a crank pickup signal?
> 
> I assume you run crank pickup with the Motec?
> 
> I noticed that Autronic sell a new disc to fit the CAS with only 6 +1 slots - anyone tried one?


The errors shown in the graph show the relationship between the flywheel and the CAS.

You can cut it any way you want with different trigger discs but you will still be left with errors that are a combination of crank flex and cambelt flex.


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## Asim R32GTR (Sep 24, 2003)

This is how things should be... in order to get 100% accurat ignition timing 

YouTube - First startup with new engine managment

Asim...


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## paul cawson (Jul 3, 2003)

What is more important that the engine fires true to the cam angle which CAS is best at measuring, or at the correct degree before TDC as a crank angle sensor would be best at. Any inaccuracy at the crank angle sensor would be doubled compared to the CAS measurements


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## ExScoobyT (Jan 6, 2004)

Hugh - I `suspect` the nissan ECU (and PFC etc etc) does not actually read the CAS fully at high RPM. I `suspect` it uses the six windows in the optical disk rather than the 360deg markings. A combination of reduced resolution at the CAS and software encoding of the hardware harmonic perhaps?


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