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Just a quick question regarding tuning the higher rpm range. I have the tune for my 355 holden v8 pretty close up to about 4000 rpm. I used the ve calculator spreadsheer for the main part to help make changes. I have adjusted the map above 4000 rpm to what i think it will be, considering the cam, etc. My question is, do i just have to run some logs in high rpm and wide open throttle and just keep an eye on the wideband in case it goes lean? Are there any specific methods to tuning this area in the map considering it is more risky if it runs lean compared to light throttle and low rpm? I want to know i'm tuned safely up to 5500rpm. Cheers.

You shoud be able to see the VE taking shape in a way. Set it to what you think it'll look like then richen a bit more and get some logs up to say 5000 then got 5500 the 6000 if possible.

Excellent thanks for that, i'll give it a go.

Post up your bin and some logs id love a look at it. Whats the engine specs? Trans?

355 stroker, approx 10:1 comp, crane 276, standard vn heads, yt 1.65 roller rockers, std inlet manifold, pacemaker extractors, twin 2.5 inch mandrel bent exhaust. I am very light on with ignition timing as it is a small cam for 10:1 comp ratio. I have about 10 degrees initial and 21 total for the time being. I have plans for a bigger cam in the future so not too worried about it being knock limited at the moment.


I have had this set up for a couple of years now, but with a Haltech running the show, however I am going to sell it and run the delco instead. The map from the Haltech was a good start but not exact for the delco, hence why I am retuning. It was a good starting point though which helped a lot.

Oh yes and t5 manual and 3.7 diff gears. Thats pretty well the whole set up!

Should be a good goer. Have a look at the BAYA bin it's the VN Group A tune they ran that cam see how there timing is think there comp was high 9's. Even stock VT bins have around 26 degree timing with 9.5 comp.

Have been tuning a similar combo, 355 with decent alloy heads, slightly smaller cam and about 9.5:1 CR and seems happy with 28° timing, will possibly take more but we're going to fit a knock sensor before pushing it any further.

My static cylinder compression is around 200psi which I think is a tad high and maybe contributing to the problem. Basically, it will ping with anymore advance once the engine is at running temp and i even pull timing out when the intake air temps pick up. I am wondering if it might actually by higher than 10:1, unfortunately i did not get the engine builder to write it down, he just said verbally it was about 10:1.

I have a torque power dual plane hi rise to go on so I think that I wont have an issue with that manifold. I am tuning the delco with the standard manifold now as practice and as a tune to have saved in case I have to go back to a standard manifold in the future.

Have you double checked your base timing is at 10 deg?

Yeah that was one of the first things i thought of when i first noticed it ping in hot weather.