[99 Se-l]

What is the best timing for S4 cams with a stock ecu?

 

[Guest]

15 degrees

 

[Black200SXSER]

Why would you have to run 15 with a stock ECU...? it should be just like any other cam set..run it up to 17...

 

[morepower2]

Why would you have to run 15 with a stock ECU...? it should be just like any other cam set..run it up to 17...

S3 and S4 cams are so good at cylinder filling, you don't need to bump up the timing to increse peak cylinder pressure. More timing gives you less power most of the time. The S3-4 JWT program gives you more bottom end and more power past the peak but has less timing at the power peak.

With no ECU, we have found with multiple dyno tests that 15 degrees is the best.

Mike

 

[Black200SXSER]

With no ECU, we have found with multiple dyno tests that 15 degrees is the best.

bam! there ya go...cannot argue with dyno runs...

 

[99 Se-l]

Thank you all for the responses.

 

[1FastP11]

With no ECU, we have found with multiple dyno tests that 15 degrees is the best.
Mike

Hello sir,
Is it possible for the roller engine to respond differently to timing than the non roller SR20DE?
Have you played with the timing on a camed roller SR20? I've been trying to find optimum timing point and humbly this is what I came out with.

I have Roller S3's on my Primera and unfortunately I have no access to a dyno for tuning. But I do have this
http://www.speedoptions.com/news_headline.asp?aID=2145&ref=default&v=4&pg=0
It is pretty consistent if you are accurate on the measurements. I found out that 17 deg timing yielded the best numbers on my testing with stock ECU and the roller S3's. The measurements I made are from 40 Km/h to 100 Km/h (fuel cut) I always do it in the same street, floor it @30 Km/H on the same spot of the street and on second gear, always trying to make the measurements with the same
amount of fuel (weight constant). I average 5 runs and got this results.
With timing at 16 I got 6.17 seg
with timing at 17 I got 6.09 seg
with timing at 18 I got 6.25 seg.

Did that came out right? I'm a spanish speaker, sorry if it didn't got through.

Thanks
BTW, the noise was not coming from the camshafts, many thanks for the prompt reply sir.

 

[Ninety-Nine SE-L]

are you also planning on getting an ECU in the future? you'll do so much better with the combination of the two. I even heard that WES got an extra 40HP after adding the new 1.6 cams and ECU.