DIY Porting for an idiot

Rich H · Post by **Rich H** » Wed May 31, 2006 9:59 pm

Hi gents,

As you will all know by now I have a bit of technical knowledge, a problem with compulsive pruchases and alot of time. Oh and I'm an idiot

As a result I have embarked on another barmy, ill advised and probably unfinished project: DIY porting

The story so far:

E-bay head: £20 + £10p&p
Tooling £10
Bead blasting 8 Stella
16 new springs and spring caps £7.50 inc p&p

Progress so far:

Valve seats opened up to match casting
No.1 2x Exhaust ports opened slightly ~2mm
No.1 1x Inlet port valve guide and guide boss ground down, port opened by ~3mm

Pics:
Before (No.2 Inlet)

Half done (No.1 Inlet)

More pics to follow.... (In 2 weeks again

)

Rich
(I am not a mentalist

)

Rich H · Post by **Rich H** » Tue Jun 20, 2006 2:01 pm

Got 4 inlet valve ports done now, 4 to go. Using up dremel spira-bands at a pretty rapid pace and my electric drill is getting pretty rumbly (Probably knackered bearings) but it was free anyway.

Anyone know of a decent engine referb place with a flowbench to see if I have got any improvement? I have got a plan to build one but I don't have the space for it.

Rich

mac · Post by **mac** » Tue Jun 20, 2006 2:04 pm

Just being a dummy here but.......

Wouldn't you have had to flow test it before to see if you have gotten any gains?

Mac

Rich H · Post by **Rich H** » Tue Jun 20, 2006 2:07 pm

I'm assuming that the standard heads are at least similar, a significant difference should be easy to spot.

That's the plan anyway....

Uldis · Post by **Uldis** » Tue Jun 20, 2006 2:13 pm

Exactly.

I hope you're taking this as a learning how it feels to port, because I see some problems:
-you wore into the valve guide. If you were going to run this head the shirter stem would mean it would be less stable and would wear quicker. Therefore the Colsibro guides people install when doing thisd: they are harder.

-you're just openening the duct as opposed to giving it a shape to fill the combustion chamber in a certain way.

-there would be very limted gains if you don't install bigger valves. If you do, porting has to be done after installing the new (bigger) valve seats.

-you don't mention which TB's or induction you're using, but care must be taken to match the bore and exact position of it so that there's no step.

Just my 2p.

Rich H · Post by **Rich H** » Tue Jun 20, 2006 2:25 pm

As you say this is only an experiment, the head was cheap anyway. I would just like to know if I have achieved anything. The valve guides have been taken back to the port wall as I have pictures of a successful K16 head cut like this. How long it lasted I don't know.... Replacing the valve guides with bullited ones is always an option. (So is scrapping the lot!)

The ports are opened up and rounder throughout. It's difficult to get a decent picture. Behind the valve is more bowl shaped and the valve guide and boss is cut back to the wall. The valve seats have been enlarged slightly to match the throats. The exhaust ports are slightly opened up too.

The guide I have is more about flow rates rather than performance it has to be said.

Rich

Brunty · Post by **Brunty** » Tue Jun 27, 2006 12:06 pm

I think you'll get a better result with opening up the exhaust side before the inlet side.

At least it will breathe better and should be slightly more responsive rather than much more powerful.

Brunty

Rich H · Post by **Rich H** » Tue Jun 27, 2006 5:27 pm

Do you mean pick up fasater? That would be good

TBH I have only the vaguest idea of what I'm doing but it keeps me off the streets and from spending any more money!

Cheers gents

Rich

Rich H · Post by **Rich H** » Tue Jul 18, 2006 2:36 pm

Update time I suppose, more pics to follow.

All of the inlets are just about done now. Just one valve seat that is a little thin at about 1-1.2 mm where I got a bit acrried away with the grinder and I'm not convinced anymore that cutting the valve uides back was a good idea. but we'll see....

Exhaust ports:
Before:

After:

Rich H · Post by **Rich H** » Thu Jul 27, 2006 11:15 pm

Right bulk of the work done on porting, the exhausts have been opened up to the gasket, about 3mm all round:

Inlets opened up to the VVC gasket (For that VVC manifold Shug

) and the valve guides and bosses cut back to the port walls:

The remaining work is to buy some more spyra bands for the dremel I have used about 8 so far and finish tidying up the exhuast ports. Grind in the rest of the vavles and re-assemble the Lot.

I have the Piper 270H cams to fit but I have no vreniers as yet but I do have a plan (Well a man with a plan!) for an adjustable sproket drive pin which could be interesting. If it doesn't work I'll have to cough up for verniers

All I will then need is cam sealant, cam lube, head gasket, cambelt, tensioner, oil and coolant

May be finished while I'm still in Scotland...

Post by **Shug** » Fri Jul 28, 2006 10:44 am

RICHARDHUMBLE wrote:Right bulk of the work done on porting, the exhausts have been opened up to the gasket, about 3mm all round:

Inlets opened up to the VVC gasket (For that VVC manifold Shug ) and the valve guides and bosses cut back to the port walls:

The remaining work is to buy some more spyra bands for the dremel I have used about 8 so far and finish tidying up the exhuast ports. Grind in the rest of the vavles and re-assemble the Lot.

I have the Piper 270H cams to fit but I have no vreniers as yet but I do have a plan (Well a man with a plan!) for an adjustable sproket drive pin which could be interesting. If it doesn't work I'll have to cough up for verniers

All I will then need is cam sealant, cam lube, head gasket, cambelt, tensioner, oil and coolant May be finished while I'm still in Scotland...

Can meet up sometime this weekend to give you the manifold. It's in the boot.

Rich H · Post by **Rich H** » Fri Jul 28, 2006 1:44 pm

OK, any suggestions? My weekend is pretty much empty but I'm hoping to make it to Alford on Sunday

Post by **Shug** » Fri Jul 28, 2006 1:48 pm

RICHARDHUMBLE wrote:OK, any suggestions? My weekend is pretty much empty but I'm hoping to make it to Alford on Sunday

Was gonna head up to Glasgow to help out Dom in a BMW 'parts sourcing' exercise (angle grinding tatty old shell off a respectable engine/diff) for his autotest beastie tomorrow. Lemme know if you fancy some tw@tting about in a yard with some power tools....

If that doesn't appeal, I could still meet you somewhere halfwayish. Weather supposed to be rotten tomorrow, so not much point organising a blat....

Rich H · Post by **Rich H** » Fri Jul 28, 2006 6:09 pm

Yeah I'll be up for some directed violence after the week I've had

When and where?!? I'll bring "the special" for a second opinion...

Rich

mckeann · Post by **mckeann** » Fri Jul 28, 2006 7:15 pm

i have verniers sitting in my garage going spare