More KW.

[irwin83r]

If you need a deal on a microtech I may be able to help you out...

my new best friend




what kinda power would my car be making at a guess with new cams and ecu??

83kw atw at the moment. NB8A with cold side short CAI, 4-1extractors high flow cat straight through rez and muff..

anyone want to have a guess??


(sorry for hijack pcmx5 .. but i must thank you for opening my eyes... i really thought cams and ecu would be close to 3 or 4 grand )

[Babalouie]

what kinda power would my car be making at a guess with new cams and ecu??

...depends on how big the cams are

[Okibi]

100 kW (at a guess), with cams, an ECU, intake and exhaust.

[pcmx5]

100 kW (at a guess), with cams, an ECU, intake and exhaust.

Irwin, OKibi is spot on,101.6RWKW if you got the same gain as me(27%).However it is not just the power but the torque and drivability that is also critical.Anthony is a very experienced tuner and he drove my car to work for a couple of days to ensure that the tune he did was suitable and what I wanted.

Your 80kw starting point is much more than NA8's and NB8A's have ever made at Vic Club days(Dyno Dynamics dyno), ours were typically68-74NA,74-77 NB8A, with similiar mods to yours so you would need to make sure you did a before and after figure when you have the work done as a reading after may partially reflect the difference between the dyno's not just the effect of the mods.eg I got 86 kw on a Dynamics Test Systems dyno at the same tune as 74kw on Dyno Dynamics.

Dyno's are not necessarily accurate or the ultimate measure but will certainly give an indication of before and after figures.

You may be able to save a bit on my costs by using Tighe regrind cams(about $550 compared tp $$920 ) plus freight rather than new ones.For mainly strreet use the 252 cams are fine.

I am sure that whatever you do you will enjoy the difference, my car is totally different to drive and I can't wipe the grin off my face.Good luck,

Peter.

[Okibi]

..However it is not just the power but the torque and drivability that is also critical.....

Yup, after driving some of the local NA8's with Wolfs i'd have to agree.

Make sure you do what pcmx5 did and leave your car with the tuner awhile, give them a chance to tune it for cold starts as well as reliable power.

[pcmx5]

OOPs, sorry Irwin, as you starting figure is 83kw that would be 105Kw on the same dyno.

Peter

[Babalouie]

A cam install in an NB will have exra costs tho, because while the NA has self-adjusting HLAs the tappets of the NB have to be reshimme by hand to get the right clearance, so you'd have to add a few hrs labour on top for an NB...still, it's no reason not to take the plunge....DO IT!!

[irwin83r]

i will have to give rick shaw a ring and have a chat to him about it all.

if latter down the track i decide to go FI will i need to revert back to the old cams??

further more. i was thinking of getting a lightened fly wheeland better clutch, though i thought i'd wait till this clutch died.. would i be better off installing the fly wheel before i get this all done so the idle and tune can be done with that taken into acount??

would it also be worthwhile getting a good streetable clutch at this time and selling standard one while its still good??

[Babalouie]

i will have to give rick shaw a ring and have a chat to him about it all.

if latter down the track i decide to go FI will i need to revert back to the old cams??

I think when Gurglr put the 805s on his old car he found that the powerband was more linear and driveable, since there wasn't this huge slug of mid range torque. So he preferred it with the big cams.

further more. i was thinking of getting a lightened fly wheeland better clutch, though i thought i'd wait till this clutch died.. would i be better off installing the fly wheel before i get this all done so the idle and tune can be done with that taken into acount??

would it also be worthwhile getting a good streetable clutch at this time and selling standard one while its still good??

Nah. Just wait until it dies then replace it. A lighter flywheel shouldn't affect the tune. DO IT And a second hand clutch would have not much value I would have thought...

[Matty]

Peter - one more question - did you fit adjustable cam gears or just use the stock ones?

[pcmx5]

Matty,

Just the standard cam gears on the basis that this was never going to be an \"ultimate power pursuit\" and for what little benefit was likely I couldn't justify the extra cost.

From what Babalouie said(if I haven't misinterpreted it) his slightly wilder cams specifify the factory settings anyway.

Peter.

[jules]

Peter,

Sounds interesting. I'm really happy that you have achieved such a satisfying result.


Jules

[Matty]

My understanding was that (due to the errors involved in the cam grinding accuracy) it's important to have adjustable gears in order to dial in the \"factory settings\".

However you seem to have had a great result without them...

[adamjp]

Almost any aftermarket cam will provide the best overall gain on the 'stock' cam wheels as that is what the companies grind them for.

Using the adjustable wheels will allow a tuner to improve the flow characteristics in the engine at a point in the RPM range. This will move the torque produced to a small extent, but what you get in one place will usually result in a loss somewhere else.

Power is an artificial number directly related to the relationship between torque (measureable) and rpm (also measureable). 50nm of torqe at 1000rpm does not produce as much 'power' as it does at 2000rpm. Increasing cam overlap (retarding inlet and advancing exhaust) will most likely improve the flow characteristics up in the rev band, improving torque (and therefore power), but usually at the loss of bottom end torque.

That is where variable cam timing is such a good thing. Delivering good low rpm torque requires valve timing events that do not produce good high rpm torque. So - adjust the valve timing as the engine increases RPM, from little or no overlap which promotes cylinder filling at low rpm, to increasing overlap for better filling at high rpm.

Sorry for getting pseudo technical, but it explains how cam gears work (or don't) in an application.

For the record, my cam gears are set on whatever they were installed to when the japanese guy put them in his car in Japan. I have no idea if they are advanced, retarded or stock. I left them as-is when the were installed on my engine. I probably don't need them to be adjustable.

[adamjp]

Matty,

My talks with Tighe before the HKS cams came up at a good price indicated that they grind cams to very fine tolerances and did not suggest that adjustable gears were of any value for chasing alignment.

Mind you, major head shaving will make some changes to the cam angles.

And if you were considering FI at a later date, they may be a very good idea. FI timing is generally different to NA timing (less overlap as I understand it).