Hello all

Like all newbies I am in need of a few tech questions answered. I was looking for the answers and did a search but nothing relevant came up.

My question is as follows:

Q: What are the Differences IF ANY on 2nd Gen heads with all these model numbers stamped on them M5, M6, M-7 and M8 ? Are these the Casting numbers that represent the model year that the heads were produced (Ex. M5=1991 Casting, M6=1992 Casting, Ect) ?

Thanks mates
Oscar

from what i know they have minor differences in shape, m9 i think has heart shaped inlets i believe and has a higher compression than previous designs?? benau knows something about this i believe

i'd love someone make a write up about the different heads and what cars they came on, etc

it would be useful

As far as what heads will fit on the 2.6L ?... Well to my knoledge NONE other !
The only way to get more power out of these heads is to go with bigger valves, roller rockers and an agressive cam and not to forget the heavy port and pollish.

But NO other vehicle has a head that will work on the 2.6L and will give it more power or better flow. As a matter of fact some guys use the Magna 2.6L head as an UPGRADE for flow on the 2.6L monteros and pajeros and all those other old school 2.6's.

Oscar

What Head was on what 2.6L (1st gen models especially) seems to be a mystery.
So far I know that GEN 1 heads are M1 to M4 cast, TR efi heads with roller rockers and round chambers are either M6 or M7 cast, and that TS with heart shaped chambers are M9, Note: I haven't seen an M1, M5 or M8 cast yet.

^ cut and paste from 2nd gen "mods" thread,
The casting numbers don't seem to represent build year but more build series, e.g there were different alloys used in M1 and M2 heads, the change was because these early heads were prone to cracking.

A-Ha !
Thanks for the info guys. If there's anything else please keep it coming.

Oh-Yes.... Benau....
Do you OR anyone else here know what is the RATIO on those roller rockers you guys use on the 2nd Gen heads ?

We here in the US swap out rollers from V6 Mitsubishi'ds to use in our 2.6L heads to replace the crapy slider rockers that came with them. But in going to the roller style we loose a bit of power down in the lower RPM's due to a bigger ratio on the rocker itself. So just wondering or confirming if the roller rockers you guys use are the same as ours.

Thanks again mates
Oscar

From speaking to a mate who is an engine machinist and also from others on this forum,
The roller rocker that were used in 2nd gen magna 2.6 are the same as those used on the Magna/Verada sohc Mitsu 3.0L V6 (US Dodge Caravan, Diamante etc)
The 2nd gen Magna 2.6L with roller rockers had a cam ground to suit the roller rockers and I have been told that the valves used have stems a few MM longer than non-roller rocker type.
Oscar, I'm guessing your looking for a better flowing/stronger head for a Starion/Starquest???
If so then magna heads have different coolant ports and need to be modified to suit the standard turbo inlet manifold.
what application and make/model do you want the head to suit?

Benau

You ARE correct.
I am modifying an 89 Starion but I am allready using a Magna MPI Intake manifold MODIFIED to suit our RWD Starions so there will be no need for machining the head's coolant passages. I was going to machine the Magna intake to suit our heads but since the Magna heads were designed to work with the intake and are better flowing and made of a better alloy alltogether and just more technology than the older early 80's coast and technology I might as well just go with a complete Magna head and Intake.

Pics bellow:

And thats what I thought they were, we ARE using those same 1.5 Ratio rollers in our heads BUT we loose a bit of power in the lower RPM's due to cam differences.

So that pretty much answers my questions.
Thanks a bunch for the info Benau

Un-modified Magna MPI Intake Manifold. Look Familiar ???
http://www.fr33z3.net/starions/m3.jpg

MPI Converted to work with a RWD Starion 2.6L PIC#1
http://memimage.cardomain.net/member_images/3/web/363000-363999/363769_39_full.jpg

MPI Converted to work with a RWD Starion 2.6L PIC#2
http://www.we-todd-did-racing.com/wetoddimage.wtdr/wMTA0MzA4NjZzNDEzZGZkMzF5NTQx.jpg


Thanks
Oscar