Astron 1 head swap

[fridgeGB]

Hey everyone. Just wanting to know if there is an easy head swap for a 4g54 series 1 engine? It's running flat top pistons and balance shaft removal kit. Do water and oil ports on the head and block line up correct on later model heads ect? Or is it too much of a hassle and just easier to track down another series 1 head to replace the old one? Any info would be great. Thanks for reading

Josh

[Scorpma82]

I'm pretty sure that the Astron II heads are interchangable....i do know that the AII's ran flat top pistons as factory......my guess is that would be your best option i think

[fridgeGB]

Cheers for the reply scorp. Bad sig mentioned also that it would swap over no problems as far as everything lining up, but he also said that he wouldn't recommend it unless fitting a turbo. I'm only guessing its because it willed top the compression too much. And I guess it's the same for all the other heads as well like the m7's ect.

[Superscan811]

Grab a M8 or M9 head (with the kidney shaped chamber) and have shaved 2mm off the head. Comp will be the same but you will have larger valves and ports, along with a much better flowing head.

The only negative is you will also need to get an adjustable cam gear and pack out the hydraulic tensioner to compensate for the extra chain length.

If you were going this way, I'd also grab the TS Magna oil pump if you were going to use hydraulic tappet setup.

All depends on your funds, free time and inclination.


Cheers.

[fridgeGB]

Cheers for that superscan. Ill speak to my mechanic about it and see what we decide

[cheaterparts]

The only negative is you will also need to get an adjustable cam gear and pack out the hydraulic tensioner to compensate for the extra chain length.

as Scott has said shaving the head needs an adjustable cam gear - you retard the cam timing about 1 deg or 2 crank degs for each mm you remove from the head

If its any help I do a redrilled cam gear that are cheap and do the job very well
PM me if you need one

[75glnt]

My head has been decked 20 thou (just under .5mm). Do I need adj cam gear? It's running without it

[geezer101]

My head has been decked 20 thou (just under .5mm). Do I need adj cam gear? It's running without it

You're not going to need an adjustable sprocket for that but you could do with making sure it's tuned as well as it can it be with the cam timing being slightly retarded. The power band of the cam has moved down the RPM range a little so it's not a drastic change...

[Sigmaproject]

Thats something I did not even give a thought to when I had a 2mm copper head gaskit fitted for the turbo setup.