43 replies to this topic

[TK383]

I don't post much on here, mostly just lurk a bit, but figured with the number of holden 6 tragics on here you lot may be interested in a head I just finished.

 

It started out as a stock 161/149 casting.

 

Got a hot tank, bead blast & crack test to make sure I had a good one.

 

Then:

Mill to equalise chamber depths as much as possible.

Spring seats recut parallel with face & to suit 1.5" dia valve springs.

Machined for screw in studs & guide plates.

Machined for bronze guides - guides are CHE to suit 7mm valve stems.

Seats cut for 1.69/1.42" valves - which are machined from 7mm stem blanks.

 

Then I cut out the intake head bolt bosses & machined it to take capscrews in the bottom of the ports & 3/4" UNF alloy grub screws in the top.

Ported the crap out of it & then made up the intake vanes to divide the intake ports & improve the velocity profile without being detrimental to flow V's fully open port.

Exhausts got small plates inserted to properly divide them.

 

I have shaped the chambers & sized the valves to maintain velocity into the cylinder for as long as possible (pressure recovery) to maximise cylinder fill.

Ports are sized for peak HP between 7000-7500rpm on a 208 cube engine.

 

As it sits the head will support up to 350hp on a very well built competition engine with triples, 12.5:1 comp (E85), tuned intake runner lengths & custom tuned headers.

 

Flow figures:

 

Intake

Lift - flow (cfm @ 28")

.1 - 52

.2 - 100

.3 - 140.5

.4 - 162

.5 - 185.5

.6 - 201

.7 - 206

.8 - 212

 

Exhaust

lift - flow

.1 - 49

.2 - 85

.3 - 110

.4 - 138

.5 - 155

.6 - 162

.7 - 171

.8 - 179

 

Average velocity on the 'active' side of the intake vane is around 210ft/s, on the secondary side it's around 135ft/s - so the vane is doing its job.

Flow with & without the vane varies only about 2cfm.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Edited by TK383, 16 December 2015 - 07:59 AM.

[TK383]

Valve sizing lets the valves fit inside the bores with .060" offset head dowels - that's one of the reasons I went with the smaller than normal valves.

That means we can run some real lift - will get .630" intake & .590" exhaust lift with a 1.7/1.6 rocker combo.

 

For flow testing I just set the head up where it'll sit on the bore, bore adaptor doesn't have reliefs or anything, so would probably flow a little more on the actual engine with block reliefs.

 

I'm a big believer in port stability over flow, I want a stable port to as high a lift as possible - I actually tested out to .900" lift & it kept gaining on both intake & exhaust - never backs up or goes turbulent.

 

The engine *may* be on a dyno before the end of the year, but maybe early next year, I'll come back with results & the full combo.

[orangeLJ]

I actually just posted a link to the pf threqd a few days ago.

Nice to see you found your way over to post yourself.

Interesting work.

[LC-GTR-1969]

Extremely impressive, and thankyou very much for sharing on the forum.

 

I am intrigued at how you have managed to get the port flow increasing over .900" lift, as you say the port must be very, very stable.

 

Please post back with some more details of dyno figures once its all together and tested. 

 

Well done- and great to see there is still some development happening with the ol' 9 ports!

[SA EH]

Nice........Like!

[greens nice]

Wheres this thing at?

[LC-GTR-1969]

I think TK might be easy to contact through the V8 forums, I think he is a little more regular over there...

[TK383]

Owner has had a feew delays due to work etc.

 

Should be on the dyno within the next 4 weeks - I'll let you lot know the results.

 

I'm currently doing an even more radical 9 port head - shifted the intake valves .060" towards the centre of the port to unshroud them & allow the use of a 1.72" valve with still .040" less shrouding than a 1.68" valve in the stock location.

I've also plugged & redrilled the dowel holes to shift the head .060" over on the block to further unshroud the valves.

Head has also been angle milled.

Valves are 1.72 & 1.4" Ti 7mm stem, guides are CHE bronze.

I'm using a new desing for the vanes.

 

Flow in development has hit 225cfm on the intake with very, very strong mid lift flow, exhaust has hit 17xcfm & is also plenty strong right through.

 

This one will be on E85 with webers & a solid roller cam in the 250's duration & around .680" lift.

 

I'll put some pics up when I'm done with it.

[greens nice]

Excellent, I'm keen to see some numbers from the big black sticky thing!

[LC-GTR-1969]

Yes, please let us know the results... 

 

Flow in development has hit 225cfm on the intake with very, very strong mid lift flow, exhaust has hit 17xcfm & is also plenty strong right through.

 

Wow, extremely impressive! Thats a little more than what my irving flowed... 

 

 

This one will be on E85 with webers & a solid roller cam in the 250's duration & around .680" lift.

 

Sounds great... thats a lot of lift... I imaging the pistons will need to be flycut? 

[TK383]

Likely no flycut required - angle mill helps with that as does sinking the seats into the chamber for improved pressure recovery.

 

Flow figures so far:

 

Intake

.1 - 56

.2 - 118

.3 - 158

.4 - 189

.45 - 202

.5 - 213

.55 - 219

.6 - 220

.65 - 222

.7 - 225

.75 - 226

 

Exhaust

.1 - 49

.2 - 91

.3 - 119.5

.4 - 145

.45 - 151

.5 - 158

.55 - 163

.6 - 167

.65 - 171

.7 - 174.5

.75 - 176

[LC-GTR-1969]

looks good and stable... flow increasing right up to .75!

 

Intersted about the webers on E85... Any reason not to use HD8s? I reckon the 2 incg SUs would be a good thing on E85 with the 9 port but could be wrong... 

[TK383]

Me too, I think 2" SU's will have the edge in outright HP, but the owner has the webers already & the difference is unlikely to be night & day.

Webers will certainly drive better & tuning is likely easier for E85.

[LC-GTR-1969]

Me too, I think 2" SU's will have the edge in outright HP, but the owner has the webers already & the difference is unlikely to be night & day.

Webers will certainly drive better & tuning is likely easier for E85.

 

How much would one of these heads be worth TK? You can PM me if you prefer... Your work is truly art mate, almost a shame to hide it by putting it on a block!

[TK383]

Haven't worked out final cost on this one yet.

Spent 2 whole days machining stuff before I even picked up the grinder, then another 2 days on the grinder with likely another full day to go, then gotta set up the valve train & cut down the Nascar surplus Ti valves.

Likely to be $5-6k in labour without parts, parts will likely exceed $2k.

 

Would take a dedicated 9 port man to commission another head like the one I'm doing now.

 

Owner has a JZed head at home, but does not want to use it, he wants the numbers/times with a factory 9 port casting.