163 replies to this topic

[orangeLJ]

G'day mate, Which rods and pistons do you have there,if you are unsure which way to go with the crank see if you can drive a car with a full weight crank,then drive one with a lightened crank,there is a difference. Or if you are near sydney i can take you for a drive,if you send down a crank we can knifedge it for you or grind it ready to use,mick

Custom JE forgies from the states (to suit our combo) H beams are custom again, but they are essentially a Honda H beam with a few differences.

Wish I could stretch to a JZED heads, but looking to spend some $$ on injection instead of running the 48mm dellortos. Just need to find someone that does a decent manifold (with good injector placement) and doesnt want to charge the world. I dont much like the idea of running weber manifold with aftermarket injection slapped on, kind of defeats the purpose (to me anyway)



Pics of your crank would be EXCELLENT Warren! and very much appreciated.

[greens nice]

.120" is pretty damn thin in my eye's, is your block grout filled?

[greens nice]

It sounds thin but its ok in a n/a engine ,I definatley know of speedway engines with 3.720"bores and heard about others with 3.740".No mate my block is not grout filled..I've only ever seen bore problems on hp blocks bored .125" and that was from water jacket corrosion.I suppose the real reason for the bigger bore is to help unshroud the valves(also move the head across).Been toying with the idea of offset boring but havnt been game to do it. Hows the EH goin Kevin?

i try to keep overbore to a minimum and push the head over.
i moved it over .160".
yes mate getting there hopefully should be a bit quicker too.

[warrenm]

Yep HD8 my type error, what performance differences did you find between red and blue heads.Do you know what the blue head flowed ? We seem to have found a limit with intake flow with 12 port heads.

I haven't got any specs from the 2 heads, but I know a 12 port is limited to around 280hp at the flywheel & the 9 port can be 300hp +. The 12 port ran a best of 104mph & the 9 port 105.5 using the same cam.
The alloy Yellaterra wouldn't be too bad a starting point if they made it with a 47cc chamber instead of the large chamber, as Bomber has already pointed out.

Edited by warrenm, 17 August 2012 - 08:05 AM.

[wot179]

Tell me more about pushing the head across.

Do you offset drill the headbolt holes then press in sleeves?

[orangeLJ]

would flycut, lump style pistons help with the compression issues in the 12 port (thinking out lound here?)

would obviously make it an inteferene engine, but could be worth the gains (lots of $$ on custom pistons though really)

Has anyone ever tried angle milling/angle decking a Holden six head ?

[Stinga]

.120" is pretty damn thin in my eye's, is your block grout filled?

i like this thread!

has anyone had any success with sleeving bores?

[Heath]

Yeah I know a guy who has done moving the heads across and angle decking, both with reportedly positive results.

Tell me more about pushing the head across.

Do you offset drill the headbolt holes then press in sleeves?

You only move it over a mm or two, I think you just slot the headbolt holes a little, no sleeves required and the bosses in the head are still okay, The locating device is just the dowels which you have to change - you just offset drill those in a larger size (on either or both the head and block) and use larger spigots/dowels.

Edited by Heath, 17 August 2012 - 11:13 AM.

[greens nice]

would flycut, lump style pistons help with the compression issues in the 12 port (thinking out lound here?)

would obviously make it an inteferene engine, but could be worth the gains (lots of $$ on custom pistons though really)

sure do.
re the lumpy's sure you could but you would be making the piston alot heavier. which is the last thing we want to do with a holden 6.

i could have moved it another 50" before i run into problem's. but the water jackets get awfully close to the flame ring.
i just set it up in a mill and elongated the holes, you have to cut into the tappet cover area a little bit so that the head stud washer's will seat.
fingers crossed it hasnt weakened the deck at all.
no need for sleeve's, there is no water to hit for a long way yet but you have to sort out some way of clamping the bolts in the intake port's.
you can no longer use a short allen headed bolt and the yella terra style post's wont cut it.
i think it was a well worth it effort, i struggle to get .550" lift with 1.7 inlet valves but now i can drop a 1.75 inlet down so far that you can see the collet groove poking in the port hehe.

if a little is good, more is better.

Edited by greens nice, 17 August 2012 - 06:41 PM.

[Stinga]

i just meant sleeve's as another way of strengthening the block?

[greens nice]

i just meant sleeve's as another way of strengthening the block?

i was replying to wot, but no ive never tried it.
and heath i just made up some .160" offset dowels out of alluminium in the lathe.

Edited by greens nice, 17 August 2012 - 07:08 PM.

[wot179]

So how did you go about clamping in the intake ports?

Mine are hogged right out,no posts.

[greens nice]

So how did you go about clamping in the intake ports?

Mine are hogged right out,no posts.

havent done it yet but i reckon contouring the top and bottom of the tube to suit the port shape and having it tap in from the manifold side might do the job.