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Hi All,

Havent been around for a while, because once I had my ute tune close, life got in the way, and I kinda gave up and drove it as is. (

Well, life gave the ute a kick in the teeth not long ago when it swallowed 500mls of water during a "Too Deep" water crossing. It started and ran after this and got me away from a potentially terrible area, only to "Implode" about an hour later, by snapping a conrod, the cam shaft , and pretty much smashing the bottom of one cylinders to pieces. It was fairly spectacular when holes in the sump appeared and the welsh plug at the back of the block was pushed out at the same time.....

Anyway, so not wanting to be off the road for months, I decided on a quick and fairly cheap solution of purchasing a already built engine.

The specs are :

Standard 304 block / heads / crank etc
Hypertec pistons
ARP main and head studs (And some weird girdle thing on the main bearing caps I had to mod the sump for)
Crane anti-pump lifters
Crane bolt on roller rockers
RollMaster timing chain
VT Injectors
Heatseeker HS30A cam - Gross lift - 567/474 Cam lift - 292/296 Adv dur - 280/285 050 Dur - 212 / 217 Valve event - 31-69 / 73-32 (Zero idea what this means)
BT1 HD Valve Springs

Im guessing the only 'real' go fast bit there is the cam, which Im a little worried about because it does have a fair lumpy idle, which is going to cause havoc when rock crawling, im really hoping I can somehow use the tip-in / RSDC to smooth this out, at the moment when trying to drive around on idle, its running on Kangaroo juice.

So, as the previous engines tune wasn't great to start with, I decided to start again with a std 12p 112 bin, I then borrowed some info where Dylan put settings for VT Injectors into a VN bin, and went from there.

After a few hours of VE tuning and then bumping the spark advance up, it 'seems' to drive okish.

I ended up with this
When I saw how hideous the 3d graph looked, I tried to smooth it out, and haven't been for a drive yet, but heres what I did.
I also enabled the knock sensor logging, lowered the high speed fan engagement to 92c and corrected the VSS settings for the ute too.

Ive also brought back my dreaded "nearly stalling when coast up to the lights" issue again, which were the bain of my existence, and Im really hoping will go away when I get the VE and spark right.

Im really hoping that people wont mind if I ask for a little guidance while I go through this process again

Thank you all!

Glen

Good to see you having a crack and making progress it's a fair size cam but should be abe to tame it some more. Do you have a log to match one of those BIN's?

Dylan wrote:Good to see you having a crack and making progress it's a fair size cam but should be able to tame it some more. Do you have a log to match one of those BIN's?

Hi mate, thank you! I dont have a log yet. I will do one today when I try out that smoothed out bin and will report back asap

Yea, I must admit, I am a little worried about the cam.

yeah that cams massive for a rock crawler!

Holden202T wrote:yeah that cams massive for a rock crawler!

ahaha I dont know much about cams, but it certainly doesn't feel like it will enjoy the sub 1000 rpm range

I went for another drive, and more VE tuning...ended up with more peaks in my graph, from what ive read that can happen naturally from manifold / exhaust etc ?? Should I smooth and keep tuning ? Or perhaps enable WB triming and cross my fingers ?

I added another 2 degrees across the board with timing too, and have yet to detect any knocking....I think Ill have to test my knock sensor, because I was sure there would have been something by now, but then again, I have no idea how much this cam has changed things.

Heres the tune im running at the moment.

And heres a log I did of a WOT run in 3rd. Plus an example of the bunny hopping at the end.

Is there anything in the tip-in / RSDC that would help keep this under control ? although....I also need as much torque as possible early on in the RPM's for crawling......not sure what to do there.....


Thanks !!

Glen

SirGollum wrote:I added another 2 degrees across the board with timing too, and have yet to detect any knocking....I think Ill have to test my knock sensor, because I was sure there would have been something by now.

The cam isn't all that big but it isn't suitable for a slow crawling 4x4. You may not get knock yet because of the cam but it also depends on your actual and dynamic compression ratio. If you do a compression test, when the engine is at normal operating temps, what pressures do you get on the gauge? Cam events and timing have a huge effect on dynamic compression ratios, if you have a low dynamic ratio you won't get knock as easily as you would if you had a high dynamic ratio.

actually...now ive just watched the log.....ive realised how terrible the tune still is

the VE table doesn't look too bad, if you get peaky bits though, see what other stuff looks like around it, if its the only high point then its possibly a false reading.

the spark table looks a bit jumpy, might be worth smoothing it out a bit.

with my experience of tuning a big cammed V8 it needed more fuel anywhere below about 2000rpm to be happy, like 14.2 AFR ....

but you'll get there with time.

below i have attached a file, it was a 304, 10.5:1 compression, big crow cam, the injectors were bigger than stock, so it might only be useful to reference the ve and spark settings.... this $12P was a copy of the $11 tune it was running and converted to $12P, but it didn't ever get driven on this tune only the $11 version of it .... anyways if you want to use it to see what the VE and spark tables i ended up with your welcome to it .... but if you do try the tune at the very minimum i'd put your injector rate into it.

Have a look at this one. Changed your spark table a bit when it was bunny hopping the spark was jumping bog time hopefully this s better.
Increased the transient IAC steps to help with the slowing to a stop trouble. Going on that log the wideband is following pretty good maybe look at some of the AE at higher RPM and maybe look at lowering the idle VE still too. It's idling with some fairly high IAC steps maybe open the throttle stop a bit more as well.

I can have a play with the VE from a log of this one if you want and try some different AFR's too, get a log from cold and see how consistent it is.

Hopefully it's a bit more driveable on this one.