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i'm with vlad. valve springs.

Since the last Dyno day I've installed a HEI coil, installed a kinugawa wastegate actuator with a 5psi spring in there (should work out to around 4psi boost), an adjustable fuel pressure regulator and a set of 440cc injectors should be arriving tomorrow.

Crowcams have a set of springs that'll fit though that does mean the head needs to come off. I'll see how far I get with the lower boost and maybe the HEI coil picks up a little up top otherwise it's time for springs.

No luck with cams or springs, crowcams don't carry anything for these motors anymore. I'll pull a spring and measure it and try find something close.

Still waiting on a boost tee so I'm stuck at 3.5psi wastegate pressure. 71kw at the wheels is pretty good from 50kw and at only 3.5psi.
Idle bpw is under the minimum injector pulse width so fueling at idle isn't very good. Even using single fire mode. Compromises.

Looks good, I love this project.... For the injectors struggling at minimum it can help to adjust the idle AFRs up a bit for a slightly rich idle. You'll get slightly more fuel injected without having to cheat the VE table or anything else, and you might find you can get it to idle not quite too rich but more stable with slightly longer injection pulse.

Thanks for the tip antus! That helped a lot, now at 13.5 idle AFR its much more stable and the VE table doesn't take a dive at low loads/rpm.

I swapped the wastegate spring to a 0.8bar spring and now it makes 5.5psi out to the limiter and an extra 10kw at the wheels. Torque is pretty level from around 3k and HP keeps climbing with RPM. That sharp drop in torque I was seeing above 4k is gone with the HEI coil.

I've got fuel cut at 5500rpm and soft cut at 5250rpm. Might be a bit conservative but this engine has always had a fair bit of blow-by and there's some pretty nasty scoring on the cam lobes so I think it hasn't had the best life. Might pull a rod cap off when I change sump gaskets to see how bad this motor really is.

If anyone has a lead on a pre-emissions camira motor (or even just the head / cam) , I'd be interested to drop it in to see how it responds.
Not sure why boost creeps around 3k then levels off to redline. It clears up the 3k dip in torque perfectly though which is nice

I have a reco head that I fitted to a clients car 15 years ago that he then smashed a week later. He gave me the wreck. This is all I kept.

If your concerned with the valve springs you could put a spacer shim under the intake valve springs. With a std cam it wount coil bind.

Crow have a list somewhere on their site with all the spring dimensions and specs so maybe they might have something that fits from another application.

Are you interested selling that head? Those valves look a whole lot bigger than my pulsar valves which should help it breath a little, plus my valve stem seals are a bit tired so a reco head would be perfect.

Gareth wrote:I have a reco head that I fitted to a clients car 15 years ago that he then smashed a week later. He gave me the wreck. This is all I kept.

I think the roll-off in torque was the coil, seems to be gone now with the new HEI coil. The springs seem ok for what I'm asking from the motor. The boost controller just arrived but we've got 8 days of flooding forecast here.

I want to try use one of the flex outputs to switch a solenoid to enable the manual boost controller, PWM would be cool to ramp the boost in but even an off/on - 5/9psi changeover at say 4000rpm would be interesting. Can PWM be done in 12p to control a boost solenoid?

Sure, say $100 plus postage suit?