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Hi All,

I have a 99 NB8B track car.

Aftermarket intake and full exhaust it makes 132rwhp.

I realise there is variance between dyno's but approx what are others gaining in hp & torque by adding a aftermarket Ecu ie megasquirt/Haltech with a custom tune ?

Thankyou

It DOESNT make 132rwhp with an intake and exhaust.

Dann

150k km na8 bottom end, full exhaust, itbs, ported head, 1mm oversize intake and exhaust valves, .363” lift (9.22mm), 270deg duration and 226@50 cams and bigger infectious

Made 131 rwhp for memory.

If say the dyno is a bit off.

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Possibly... I'll post the Dyno, but I don't care about the figure, as I mentioned, all dyno's read different.. What is the gain in adding a Ecu and custom tune ?

I'm bordering on either just doing Ecu or spending some more and going turbo.

10% give or take.

This is mostly in leaning out the top end.

The answer is ALWAYS turbo.

Dann

By the way you cannot just lean the top end by adjusting the AFM signal or anything because the mid range is already a little lean, so.. yeh.

Dann

Thanks, so about 10rwhp peak ?

I guess I need the ecu regardless if staying NA or going turbo.

Dan your turbo kit you fab can you PM me the price incl intercooler and plumbing please.

So it's turbo, manifold, dump, injectors, ecu, pump ?

Already have hd clutch, full exhaust 2.5"

Was thinking s15 t28

No pump required.

PM sent.

Dann

sailaholic wrote:150k km na8 bottom end, full exhaust, itbs, ported head, 1mm oversize intake and exhaust valves, .363” lift (9.22mm), 270deg duration and 226@50 cams and bigger infectious

Made 131 rwhp for memory.

Sorry for the thread steal, but sailaholic, did you adjust your cam timing at all? 131hp sounds low for what you have done, unless your dyno reads REALLY low.
My NB8A with std intake manifold, completely stock head and smaller cams than yours made 134whp on a low reading dyno, (ie no mania inflated figures!!)

I found a 21kw difference (not a typo) playing with the cam timing. From 80rwkw at +4 deg exh -2deg in to 92rwkw at 0,0 to 101kw at -2ex +2in. No other changes other than moving the cam timing.

I find that EXTREMELY hard to believe, who was operating the dyno?

Dann

I wouldn't have thought it either except I saw it with my own eyes. (not 3rd hand, mate of a mate stories)
I was standing next to the car and operator for each run.

We made over 20 runs making changes to cam gears each way to see what it did.
Baseline run with cams at 0,0 as orig installed was 92kw.
Worse result was gears set to -2in, +4exh where it dropped 12kw!
Best result was +2in, -2ex and it made 101. (+2in -4ex was similar but idled even worse so went back to +2,-2 as preferred setting)

I wasn't standing watching but the operator told me he moved cam timing around trying to get more and also ignition timing. Final timing wasn't quite 0 0 but fairly close.

He seem a good operator that doesn't bullshit and is well regarded so ill trust what he said.

Nba had more compression stock, NBb had even more and a better (stock head flow) so might help explain things.

The shop says the dyno is accurate / slightly pessimistic, but it is quite common for cars power output numbers to drop a a decent amount on their dyno ( sometimes do in / out) runs when a new car comes in.


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Rascal it's very easy for the operator to fudge the dyno right in front of you unless you have an intricate knowledge of dyno operation.

Google it.

I just... Cannot believe 25-30% gain with cam timing.

Can you!?

Dann

Dann, I'm well aware of how dynos can be made to read what you want. This wasn't the case here.

We weren't chasing a number, purely showing what did what so it made zero difference whether it made 1kw diff or 100.

The car was run up 2-3 times for each cam setting to give an average number then the gears moved and run again.

The power init went backwards, from 0,0 then went up and then started coming down again with our best average being the 15th-17th runs out of 26 odd.


Besides it was a 13% loss with the wrong cam timing, and a 11% gain with more overlap, over 0,0 settings.
Its not like we installed the cams, got a number, then changed the gears and gained 25%. it was only 11% and after the 6th or 7th combination.

It also has that much overlap that it idles way worse than anyone would tolerate on a street car. I did it to get the best overall curve for a track car so considerations for a decent idle were almost nil..

NitroDann wrote:Rascal it's very easy for the operator to fudge the dyno right in front of you unless you have an intricate knowledge of dyno operation.

Google it.

I just... Cannot believe 25-30% gain with cam timing.

Can you!?

Dann

Yeah, I can confirm that it's easy to change results.

We had the fsae car on a dyno recently and the operator spent a good few hours adjusting the inertia values. We had 70-80whp on the first run. 60who once we had sorted out everything.

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