OE Iron head 355 holden street/strip - 636hp

[KnightEngines]

Tony nice job on holden. What year would those engines be? Seems like a healthy head for iron oem. I know nothing about Holden tec?

Heads & block are 90's castings, somewhere around 94, in factory form they are injected.

[KnightEngines]

Dyno reads about 10psi low, not sure why!
It's got 60psi in the car with 20/50 oil.
I reckon we'll get it down to 10.3 or so next time out, from there it'll take some more refinement of the car to get down to flat 10's.

Earlier you mentioned "turning up the vacuum". If you're running crankcase vacuum, remember that every 2"Hg. of vac. reduces the displayed (but not the actual) oil pressure by 1 psi.

Yep, I know!

Running 4" vac now, turning it up to 12" shortly.

[Steve.k]

Tony nice job on holden. What year would those engines be? Seems like a healthy head for iron oem. I know nothing about Holden tec?

Heads & block are 90's castings, somewhere around 94, in factory form they are injected.

Heads similar to a ls or they a whole other deal?

[KnightEngines]

Sort of a whole other deal, but GM looked real hard at the Holden heads when designing the LS, at 1st glace they don't look very similar, but spend some time with them & it's obvious where the LS port layout & basics came from!

[Steve.k]

Very interesting thanks Tony. I have some friends who moved from Australia they say you either race Holden or Clevelands there.

[KnightEngines]

That's the traditional 2 from the glory days of group A touring car circuit racing, there was also a few SBC's, even some jags, minis, Holden 6's - was quite varied.

[Steve.k]

Is it Holden with the Hemi six or is that Chrysler?

[paulzig]

Is it Holden with the Hemi six or is that Chrysler?

Chrysler, 215, 245,265 cu.in Hemi 6s

[Steve.k]

Ahh yes. Remember something about that. Thanks.

[cjperformance]

Vr SS with all the fruit, inc amp, subs & spare wheel in the boot!

Nice , got to love a fully loaded luxo barge, thats fast too!

On the efi head subject, i seem to remember the VL walkinshaw commodore heads were of the same style as in port layout etc? Or are they the same as VN heads?

[KnightEngines]

The VL X cast heads are early port layout with vn type chambers, l34 valve sizing & a bit more meat so you can hack them bigger than red castings. Kinda like B casts but with vn chambers.
They'll still only go 260 odd cfm ground to eggshells, maybe 270 if you hold your tongue just right & are smiled on by the porting gods.
Did I show you that r&d VN iron port I did that went 338cfm?
If not then remind me next time I see you, that is one mofo of an iron port!

[paulzig]

Did I show you that r&d VN iron port I did that went 338cfm?
If not then remind me next time I see you, that is one mofo of an iron port!

Only thing better than a VN head in an OEM small block iron would be a Cleveland head... I dont know what else the yanks have that could compare, a Vortec maybe?

[cjperformance]

The VL X cast heads are early port layout with vn type chambers, l34 valve sizing & a bit more meat so you can hack them bigger than red castings. Kinda like B casts but with vn chambers.
They'll still only go 260 odd cfm ground to eggshells, maybe 270 if you hold your tongue just right & are smiled on by the porting gods.
Did I show you that r&d VN iron port I did that went 338cfm?
If not then remind me next time I see you, that is one mofo of an iron port!

Ah there ya go , im sure id read they changed the port layout aswell (probably read that on the internet ), learn something every day.
I saw the ouc of the 330 port but no i havnt seen the 338 r&d port ! Thats nasty. Almost makes me want to chuck one in my XY , different to the typical LS or Barra !