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Is it worthwhile getting headwork done to a 94 head? The engine is going to be turbocharged - low boost for now, saving the higher stuff for later.

Are things such as head porting worth it?

Did you get any special valve jobs done at the same time?

Thanks

Based on the before and after flow figures for my head, I would say it was worth it.

Apparently the valve job was special, something about the grind used in taxi racing (Supercars), but I was kinda disinterested. My only concern was that it was better than stock.

Sabre, if you email me I will send you the port flow figures from the flow bench.

Thanks Adam, I'll send you that e-mail. What was the cost of the work that you had done?

Also, does anyone know of a good supplier of ARP head studs?

Sabre, my (old) head has:
- extensively ported and flowed inlet and exhaust ports
- relieved follower buckets for big cams
- solid lifter conversion
- cosworth valve springs and titanium retainers with NB collets
- re-profiled valves - stock sized
- multi angled valve seats
- ~40thou shave

It's a 1995 head which originally flowed 178hp and now flows 245hp. For NA power, it's the way to go but I don't understand if it's worth it for a turbo motor. I don't think it would hurt though...

ive been told that this sorta work costs quite a bit of money.

am i right to assume this?

My head costs were

Rebuild kit (gaskets, seals, etc.) $200
Basic head rebuild (rebuild, valve seats, re-facing, etc.) $450
Porting (mild, no polishing) $550

If I did it again, I would get the lifter bossess cut to allow for bigger cams.

And lets face it, flow is flow. NA or FI, if you can get more in, it will produce more power. The guy who did mine does mainly RB26 and SR20 heads, with a few 4G63s thrown in. 4G63s don't need much porting, they are huge ex-factory (bigger than 351 cleveland ports).

I have a ported and polished head for a B6 for sale if anybody wants it. It is a little more agressive than my head, but I don't need it. PM or Email me for pictures, details, etc.

Hakuna did it (DIY) - said it was best bank for buck.

http://www.pacificsites.net/~hakuna/gearhead.html


I personally would prefer to have a pro do it with a flow bench. It really is the best way.

Astroboysoup wrote:ive been told that this sorta work costs quite a bit of money.

am i right to assume this?

Thousands........by a very reputable and experienced shop. I also failed to list manley wear caps in my list of valve mods too. Simple porting is very simple but actually shaping it based on the flow bench results is more of an art. It is very much worth it but it ain't cheap. Each run on the flow bench cost me $110 and we did it a number of times to make sure it was going in the right direction with each change too.

I should have added that my porting work included flow bench tests before and after. The multi-valve japanese iron and the flow bench were the real factors I used to determine my choice of engine builder.

Other head workshops around town told me that I could not improve the porting of a Japanese head. They were wrong.

There is a bloke called John Lane at Slacks Crfeek who did Neil's head, port and polish for $880. PM him for more info.

Jesus christ, I was expecting headwork to be like $400 tops. I'll have to assess the situation, methinks...

thats what i was hoping... I suppose you can pull the head and do a little bit at a time...