DIY Porting for an idiot

[Rich H]

100k or bust

I don't know about the PG1, I may have to change the gear oil first....

[thinfourth]

2 Stroke diesel anyone:

Maximum power: 108,920 hp at 102 rpm
Maximum torque: 5,608,312 lb/ft at 102rpm

I think I may need some new tyres first....(and it weighs 2300 tonnes!)

2 stroke diesel

Now this is where i do know something

[steve_weegie]

Ahh, now here's a handy thread.....

[Rich H]

Jeebus, thread back from the dead...

The idiot is on standby incase you have any questions...

Rich
/full time eejit.

[steve_weegie]

Cheers Rich... I may be joining you in club eejit very shortly, as this plan of mine is pretty hairbrained

I should point out now that the head I've bought wasnt expensive, so........

I got a VVC head with 8 snapped exhausts and 4 bent inlets. There's been a pretty heavy contact with an area round one of the exhaust valve seats. I didnt notice how much damage there was, as I was in a suit, poking about a workshop and didnt want to get too oily! Not started any real porting work yet - been concentrating on cleaning up the combustion chamber. De-valved the bent inlets, de-stemmed all 8 exhausts and noticed that there are stress fractures in a couple of the inlet valve guides - obviously they gave up when the valves bent. Exhausts look fine though. Not too worried about these as the fractures arent deep and i'll probably grind past them anyway. This head doesnt have to last forever....

One valve seat took a bit of a clatter too, but only on the very outside & not where the valve actually seals. The combustion chamber dings have been smoothed out and I've taken the recession ledges away from round the back side of the seats.

So.... Engine plans have changed since talking to Mr Sabre heads yesterday....

Short term plan (3 months) is to build this head up to the following spec...

DIY Port Job
VVC to normal cam conversion with BP300M Cams
Cheapo Valves
Double valve springs
Verniers
Hydraulic to solid lifter conversion
Emerald
52mm Throttle Body
Give DDtB his loan head back!

Long term plan

Buy used VVC engine with decent nick head
Strip and send block & head to Sabre for "special voodoo" treatment
Nick all the good bits off this head
Get Ali @ SLS to whack it in the car
Fit Throttle Bodies at some point...

I'll hopefully get to look at a top spec head in the next week or so, and that will help me gauge what to grind and what not too.

Either I'll end up with a quickish car, or I'll make an expensive mistake & look like a complete numpty... Only time will tell

[Rich H]

A look at a proper head will hellp loads, I only had a few pics to go on so made it all up..

[steve_weegie]

Rich, did you go down the carbide burr route for most of the shaping work? Been using stones and very small balls for everything so far, but dont think these will cut the mustard for all the internal work...

[robin]

Not sure what lift/duration the BP300 cams have - almost certainly much too much for use with a plenum (assuming they compare to 270/285 in an obvious numerical fashion). IMHO the 285 spec cam is the limit for plenum operation, and it doesn't really work under 4,000RPM! Why not leave the VVC mechanism intact on the scrappo head and drive that from the emerald instead? Much better solution than lary cams (ask AndyG how nice it was driving PLO on the road ...).

Unlike most of the other connectors in the loom, the VVC valve drive connectors are "standard" junior timer connectors I think - just two connectors and four wires, straight to the relevant pins on the emerald (you need to get your emerald VVC tweaked by Emerald, but they don't charge much for it).

Then later on you can convert to heavy valve springs, solid lifters, 300-profile cams, verniers and, crucially, throttle bodies.

TBH, a well sorted EU3 VVC engine on a plenum is hard to beat without going to throttle bodies.

Whatever you do, you'll need to attack your exhaust manifold to remove clag (you know this already, I know) and match the inlet and exhaust ports (they'll be all over the place at present - you want to blend the ports and manifold openings together so there is no step - more important on inlet, but as you'll be at the limit of the exhaust manifold, every little helps on that side too). If you go to the BP300s you'll need a 4:1 solid manifold to have a chance of making the most of the cams; this in turn will need an adjustable solid engine mount to limit flex on the manifold. The 4:1 with a flexi is probably not going to work much better than the standard exhaust for BP300s (the higher the revs, the longer the primaries, rough rule of thumb).

Cheers,
Robin

[Rich H]

For the porting I used 3 cutters and a selection of abrasives things. The cutters I used was a diamond pattern tree burr, a small diamond pattern oval burr and a large aluminium burr. The ali burr has big wide flutes to clear the ali, the others got clogged pretty quick but were needed to cut the steel bits.

The abrasives I used were a coupld of med grit flap wheels and lots of dremel cylinder abrasives. The tools I used were a very cheap (and now totally shagged) battery drill and a dremel. I would reccomened a proper die grinder, the dremel was ok but slow and the drill was crap and is now knackered (I won it so not upset!) grinding puts alot of side pressure on the bearings and drills are not designed to take that.

[Mikie711]

As a side note gents, just got the QED K series parts and price list through and they do a "High performance head casting c/w seats and guides" for £550 + vat. When you consider the price of a decent VVC head even off flea bay and the cost of porting coupled with the uncertainty if it's DIY or cost if professional then it represents pretty good value. I am of course assuming that A: QED's heads are any good. B: It's similar in design to PTP Vulcan head. C: it will immediately save £110 for the VVC blanking kit. It should also mean cams will be cheaper. VVC replacement inlets are a bit dearer than the normal K's.

Mike

[Rich H]

Somewhere buried in this thread is how much I paid to go DIY, it was significantly less than £550 +VAT. That said I was not originally going to fit it but did anyway...

I think that is pretty good value if its half decent, but does a DVA/Kwik-Rog effort cost that much?

[robin]

I just checked the Piper website - the BP300's are 280 degrees duration, inlet and exhaust, and a whopping 11.2mm lift. With both valves open around 3mm at TDC on the exhaust stroke. That's not going to make for a smooth idle (indeed it may not idle at all without some careful attention to the timing of the fuel injection cycle - you'll need to inject fuel into the air at peak air speed on the intake stroke in order to avoid (a) massive fuel drop out and (b) all the fuel being pumped back into the intake manifold on the compression stroke Andy's 285H cams barely idled at about 1,000 RPM IIRC, and that's after Dave Walker mapped it.


Cheers,
Robin

[Mikie711]

Buy the time you find a descent VCC head, send it for porting and get it back then probably more. £350-500 to port according to DVA web site, £110 for blanking plate add £150 ish for head. If you change to wasted stem valves that cancels out the cost of new valves for the QED head. Hyd followers are £55 a set. It's a close call.........

To convert a customer supplied VVC head to piper 285 from Dave it would cost £1100 inc cams, porting and vernier. Assuming the head is usable.

Out of curiosity I phoned QED and the head is based on the VHPD head unfortunately Simon doesn't know eather he can get any more

[steve_weegie]

Decisions decisions decisions....

Yup, the 300's are high acceleration, high lift jobbies and with 64 degrees of overlap, they're almost hot as a brazilian sauna with kate beckinsale.

Now, if i was thinking with my sensible head on, I'd say the 300's were unsuitable for a stock VVC bottom end, I'll be lucky to get a plenum based map that will let me run the cams in properly to start with, it'll be a pig at low revs and a stable idle will be an optimistic 1500rpm. MOT's will be "interesting" and may involve "grease"

Thinking with my "skint IT consultant" head on, i can only afford to buy anything once and use it for a long time The 300's deliver power to 8000rpm, which will be my imposed limit and are as wild as you can go, running on standard pistons.

I missed out on some double valve springs that were going on ebay, so its back to full price piper jobbies for them too... This has all the hallmarks of money pit stamped all over it already!

On a plus point, all the chambers have now been cleaned up, the valve seat recession ledges removed and the valves deshrouded. With the exception of one d.i.n.g. on the face near the fire ring it looks almost viable to use now... I'm going to persevere with a DIY job on this head at the moment and invest in some "big balls" for some "throat and bowl" work If it all goes fubar, then so be it

Next purchase will be some hydraulic lifters for soldering up and a set of shims.... Unless I decide (or somebody who knows about cams tells me) that 300's are a stupid idea and I should stick with 285H's

[Rich H]

I would hold out for 285H or you are in for a world of pain when it does not run.

Get the porting started and go from there. Obviously I cannot help you with the shape of the ports, as I made mine up completely! But I suggest you start out by getting a gasket set and port matching, it will give you a feel for cutting the ali. Once you have done that you can work down each port. there are some websites out there that discuss the K series head specifically, one of the things to watch is that there is a bore that runs close to the inlet and exhaust ports, it runs diagonally (IIRC) from the face down towards the port split, that is quite close to the surface.

Good luck and lots of pics!

Rich