Head Help

[81GH]

Can anyone
confirm this is a Asstron 2 Head, need to know before start work on it,
and will fit on my 85 gk gsr siggy for EFI conversion?
Pics below
let me know if need more pics to confirm






I'm hoping it is looks like a real tidy clean head

Thanks Guys

[81GL]

Cant really see for sure from those pictures,

match up the inlet manifold pattern...



Top is A1 bottom is A2

Nick.

PS: or the difference in port dia.

[81GH]

gay looks like they gave me an asstron 1
grrrrrrrrrrrrrrrrrrrrrrrr

lame, looked like a rad head too

couldnt see or measure too well in the dark

but these holes match up with the astron1, bummer




so its an astron1 ?

[DragonCypher]

Those ones you highlighted are for the water flow, the small hole on that side means rear wheel drive only (thermostat at the front)

The main difference between astron 1 and 2 heads is the bolt pattern of the inlet manifold. You'll notice on the back edge (closer to rear of motor) the astron 1 has bolts above and below the port, whether as astron 2 has diagonal bolts
So yes, your's is Astron 1 ;)


While on this topic, is it possible to drill and tap a Magna Astr2 head and put in more studs?
To fit a sigma turbo inlet manifold without making an adapter

[Leethal]

i know that efi magna heads have an i.d code cast into the head between the exhaust ports which should make it ez to i.d. wanting to do the same converson at some point on mine i have been told that an M6 or m8 head is the go and thats what u should see between ex ports 1 & 2 i think it is also read on here that taking 2.5 to 3.5 mm off the head to bump the comp ratio is very worthwhile

[81GH]

i know that efi magna heads have an i.d code cast into the head between the exhaust ports which should make it ez to i.d. wanting to do the same converson at some point on mine i have been told that an M6 or m8 head is the go and thats what u should see between ex ports 1 & 2 i think it is also read on here that taking 2.5 to 3.5 mm off the head to bump the comp ratio is very worthwhile

yeah got a magma head today, only a m4 head i think, Are they still alright?
the plenum from tr/ts magma seems to fit on it ok, just had quick look





cool thanks

[panda]

Nothing wrong with M4 heads. TR/TS efi will bolt straight up, no probs. These heads have the roller rocker cam with hydraulic lifters. But, many of these after 15-20 years have 'sticky' lifters. If any appear stuck, replace all 8 as they're not fixable. Generally about $50 a set.

panda

[Sigmaproject]

While on this topic, is it possible to drill and tap a Magna Astr2 head and put in more studs?
To fit a sigma turbo inlet manifold without making an adapter

Best to get alloy sections welded into place on your turbo inlet and just drill the holes as required.

[81GH]

went to wreckers yesterday and confirmed
that the M4 head was off earlier magna (tn tp)
not a tr ts like i asked
most of them seem to have m6 m7 heads

so once again they have giving me the wrong head

shuld of gotten it myself wouldve been cheaper too
so prob cant take it back now, that swapped twice.