30 replies to this topic

[AndyMiniMad.]

Ok so I know that some places will sell you an engine or cylinder head with a specific state of tune, Which they like to call Stage 2, 3,or 4. But am I the only one who finds it difficult to reply to some of the queries on the forum when people ask a questions relating to stage "whatever" engines? I mean..what is a stage 3 head? Do all the places that would sell you these things have the same spec?? No...I dont think so..Please can we stop calling these modifications by Stage numbers. Im just getting totally confused by it all. Maybe its because im getting old...So very old....

[TopCatCustom]

I think we need to come up with guidlines for "stages" as at the mo I don't think there are any. I agree with you it's a minefield and can be a load of &#@$£&* when comparing cylinder heads etc that have been modified.

IMO for cylinder heads it should be something like the following:

Stage 1: cleaned up castings and ports, seats bended to ports etc.

Stage 2: ports fairly standard size, guides and bosses modified/opened up, slightly bigger valves fitted.

Stage 3: ports completely worked, big valves fitted.

Stage 4: huge valves fitted, ports opened up as big as possible for optimum flow on high lift high revving motors.

[DAVEY_C]

could be wrong but i thought they didn't fit larger valves in a stage 2, thought it was just porting/pollishing, some combustion chamber work and decoking?, was under the illusion larger valves started at stage3 and went up to stage5 full race spec??

[TopCatCustom]

could be wrong but i thought they didn't fit larger valves in a stage 2, thought it was just porting/pollishing, some combustion chamber work and decoking?, was under the illusion larger valves started at stage3 and went up to stage5 full race spec??

I think thats exactly the point- there isn't any set standard for head work so everybody has different ideas.

My post was just the start of a suggestion for a standard!

[Cooperman]

All this "Stage this-that-and-the-other" is completely meaningless in reality as there is no standards to apply.
It's mainly done for marketing and sales effect as owners, not just of Minis, like to be able to say "my car is 'Stage xx tuned". It just helps to sell kits really and that's all it's about
That's not to say that the kits don't improve performance, they do of course, but it can be better to buy parts yourself on an individual basis.
Maybe the 'Stage' thing comes from the old FIA modifications for competition where there was 'Group 1' and 'Group 2'. With Group 2 big-valve heads were allowed together with modified exhaust and gas-flowed inlet manifolds.

[DaveVader]

I agree with Cooperman.
One man's stage 2 head could be another man's stage 3.

If you're going to have headwork, take it to a machine shop, set a budget, ask them what they can do and what they advise. That's pretty much what I'm doing.

[boffster]

Read About Half Way Down The Page.

I guess this was some effort made by the site but as stated, everyone has different interpretations but a specific definition would be a good idea. Keeping Stage 5 as specific race and high end development stuff is a must and Stage 1 as non-stock air filter and exhaust. Then fill out 2, 3 and 4 with the inbetween bits.

Or maybe not using Stages but instead use the groups the camshafts use (Stage 1, Mild Road, Fast Road, Rally, Race, Full Race).

Edited by boffster, 23 March 2011 - 12:03 PM.

[Bungle]

the bigger the number the more money people think it's worth

so 2 heads the same spec for sale, the one that's stage 2 will sell for less than the one that's stage 4

[mab01uk]

It may well be a good idea to have a standard.......but as this arguement has been going on since the 1960's and beyond to my knowledge and there is never going to be anyone to actually 'police' any standard anyway........therefore it won't happen. Buyer beware is as always the key!

[Big_Adam]

Aye the idea of stages of tune are subjective, more in company than anything else.

It takes 2 secs to say "Make this a stage 3 head Rob, I'll go put the kettle on"

Compared to "Rob, go port this, put bigger valves in, then sort the chambers out, oh and sort the compression ration, got all that?"

[AndyMiniMad.]

Yeah but if his interpretation of what stage 2 actually means is different to yours then you wont get what you want, or think your paying for. I told the guys who did my head exactly what I wanted and how much I had to spend. God knows what stage it is. And to be frank I dont give a **** so long as it works well.

Edit: Spelling... big fat fingers and a tired old brain.

Edited by AndyMiniMad., 23 March 2011 - 01:46 PM.

[twrminisport]

It depends on the manufacturer but loosely

Stage 1 - Simple gas flowing, ports, skimmed
Stage 2 - Chamber modifications, serious porting
Stage 3 - Big inlet OR big exhaust valves
Stage 4 - Big inlet AND big exhaust valves
Stage 5 - All the above plus special things like angled guides, etc

Cheers

[AndyMiniMad.]

Thanks for the list, but the actual spec of any modified head is different for each one. some may have big valves but how big?? You may buy a stage 3 head and not get the same as someone else. Big inlet OR big exhaust. Its just a minefield. I feel sorry for some of the less mechanically minded members who say they are getting a stage 3 head thinking its going to be great..but not really knowing what they are getting, and maybe not having the confidence to speak to an engineering firm regarding the spec. They just buy a stage "whatever" and hope for the best.

[DAVEY_C]

imo if you buy such a head always ask the sell what work has been done and inlet/outlet sizes, thats the important part and if they can't answer then they shouldn't be selling it.... they should know what they are selling.
all these stage? heads i'd say started with tuning kits, it wasn't the head that was a stage anything but more the kit.... stage1 kit would improve performance.... stage2 bit more improvement etc etc.... then someone probably said i'm gonna take my head off and rework it to have a similar size valve etc thats in the stage3 kit.... guess what, now i have a stage3 head......
unless you are buying the head or an engine with the head fitted i would take people saying i have stage? with a pinch of salt... if your buying then i would question and request proof.... if they can't prove it then its prob no better than a standard head?

[pogie]

Another thing that makes the "Stage" numbering system ridiculous is that you cannot tell how well the modifications have been done.

A fully worked head by Joe Bloggs with a Dremel and a pistol drill in his garage is not going to be to the same standard as one done my Richard Longman or Swiftune etc, even though technically they have had the same type of modifications done to them.