Club 80-90 Forums

Yeh don't let the doubters stop you

Tought it a bit of a lesson, 48mm deep gets to centreline of exhaust port. Looks like the PAS bracket might be a casualty with the necessary bigger rocker box, but its small enough to remake cheaply, or even have one integral with the head...

Got bored so went in for a couple of hours and found some bigger tooling...

Inlet manifold defo a casualty now:

silverbullet wrote:Small block F..d 302 with 4v heads...

Aftermarket firms like Arao and Dominion Performance also had similar offerings.

only treat anything from arao/dominion as you would treat goods from a door to door duster salesman

Both went phut from what I read?

Got rid of the rocker box walls and turned some plastic tube to help visualize where its going.

Top head studs will have to swapped for long as per bottom row, no big deal.

One head's worth of late DG/DJ valves stood inside a barrel seal shows just how much *could* be crammed into a 94mm bore, but but there would be no metal between the seats, so back to the old failings...

DF valves might be an option for size but they are stupidly heavy, the stems are massive and the one thing that would desperately be needed is less valvetrain weight.
My gut says look at 7A or 9A valves but I have no idea of their length.

The more I think about the rocker gear the worse my headache becomes...the offset flat-4 pushrod arrangement plus exhaust ports on each end of the head make for a decidedly non-symmetrical rocker arrangement in my sketches so far

want me to bang you a scrap 20v 1.8 head when I'm passing next shagger??

Rather have that front deform and valance chap! 5 valve per cyl is old news, too much turbulence between the inlet valves. Even F1 teams have gone back to 4 valve, the tech never delivered what it promised, it seems...

Better 2 valve head design with bigger valves..
or.. a 3V design???

Mr Hutch.. I am at Aidans at present.. I do have to see Ian 5th or 6th Jan about some engineering issues.. so can transport some bits if you are out towards this direction.....

The 3 valve had crossed my mind.... some time at the drawing board will tell all, crude sketches are just a guess.

silverbullet wrote:Rather have that front deform and valance chap! 5 valve per cyl is old news, too much turbulence between the inlet valves. Even F1 teams have gone back to 4 valve, the tech never delivered what it promised, it seems...

My take was it may yield small vw valve options not to copy the design

motorcycle valves.. light and designed for gas flow...

I would rather keep it all VW Si...Similar sizes to the EJ would be good (35/31mm iirc) That would leave a decent land between the valve seats so the exhaust side won't get overheated and less risk of cracking around the spark plug (Subaru fail point) plus the bigger VW 94mm+ bore would give better flow.
But if the rocker gear doesn't work out its a dead duck for pushrods. Pulling the top end design and parts off a SOHC EJ22 would be the next best thing, but its all old stuff