Bird Rebuilds 1776! Job done, thanks for the help folks!!

[Merlydog]

Made a bit of progress today.. Pretty much Stripped down to the short block now, heads seem good with no cracks, but I'll let you guys decide from the pics. I can't see anything though.
Only thing I did notice is one of the push rods has split, I'm guessing it's been done whilst being moved about as the guy said it had stood for 6 months.
Anyway here's a few piccys this far.

What I couldn't work out is how to get the barrels off, I figured I leave it and consult the Tom Wilson book. The tinware was pretty crap too and had to cut some of it as the screws were jammed in the heads on cyl 1&4. No biggy though.

 

[weeboll]

A remote cooler on a mild engine is a smart move although not essential. I think a remote filter is, the oil screen that stock engines have is fine for stock engine but even a mildly tuned motor will benefit from a proper oil filter. If your really not feeling full flow how about 1 of these?

http://www.coolairvw.co.uk/Item/Sho...-1600cc_CB_Performance_Maxi_Oil_Sump_Kit.html

Good compromise I think.

Thanks Karlos, that does look like a decent compromise and less hassle too. I wonder if anyone has any experience of these?

less hassle than rebuilding an engine?

all you have to do for now is drill, tap and plug a hole!

biggest regret in getting my engine built is that i didnt get this done!

 

[Merlydog]

Right full flow it is... Seems simple enough and can only bring positives by the sounds of it.. I'm in!!

 

[Jimbly]

If I could add my £0.02-worth, I wouldn't worry too much about polishing the ports. They tend to work better when left slightly rough on anything other than a full-house race or rally engine, as a too-smooth finish can lead to fuel dropping out of the air flow onto the port wall, while a slightly rough finish will keep it turbulent and the fuel mixed in with the air flow.

I did a simple flow job on my 1600SP heads, left it carbide-cutter rough and gained 5bhp at the wheels, or around 7-8bhp at the flywheel.

And I can't recommend a proper rolling road set-up when you're done highly enough...

 

[r73]

If I could add my £0.02-worth, I wouldn't worry too much about polishing the ports. They tend to work better when left slightly rough on anything other than a full-house race or rally engine, as a too-smooth finish can lead to fuel dropping out of the air flow onto the port wall, while a slightly rough finish will keep it turbulent and the fuel mixed in with the air flow.

I did a simple flow job on my 1600SP heads, left it carbide-cutter rough and gained 5bhp at the wheels, or around 7-8bhp at the flywheel.

And I can't recommend a proper rolling road set-up when you're done highly enough...

Exhaust ports smooth - inlets rough, right?

 

[Jimbly]

Even less important for exhaust ports, as the pressure differential driving the gases out is huge, compared with inlet which is only atmospheric...

 

[Merlydog]

Even less important for exhaust ports, as the pressure differential driving the gases out is huge, compared with inlet which is only atmospheric...

Any ideas how many extra Horses I'll get from porting, adding dual springs and stainless valves compared to standard heads and 1641 B&Ps with twin dells Jimbly?

 

[Jimbly]

Can't be exact and can only speak from personal experience but switch from single to twin 34ICTs on mine gave 11bhp/14lbft at the wheels while high ratio rockers gave an additional 8bhp and 5lbft at the wheels.

The headwork gave an extra 5bhp and 5lbft at the wheels, bringing the lot from 30bhp/58lbft to 55bhp/85lbft.

This was all on a single port engine as I was looking for torque not power. Yours is a twin port so I would expect 5-10bhp from the headwork but hopefully someone with actual experience can answer?

You wont see additional power per se from the valves and springs unless you go for bigger valves - the gains will depend on the cam you choose but the high ratio rockers give a similar effect by opening the valves further and you can see the benefit from these.

Again, hopefully someone with cam experience can give you a steer - I just went with general engine experience...

Hope that helps...

 

[Merlydog]

Can't be exact and can only speak from personal experience but switch from single to twin 34ICTs on mine gave 11bhp/14lbft at the wheels while high ratio rockers gave an additional 8bhp and 5lbft at the wheels.

The headwork gave an extra 5bhp and 5lbft at the wheels, bringing the lot from 30bhp/58lbft to 55bhp/85lbft.

This was all on a single port engine as I was looking for torque not power. Yours is a twin port so I would expect 5-10bhp from the headwork but hopefully someone with actual experience can answer?

You wont see additional power per se from the valves and springs unless you go for bigger valves - the gains will depend on the cam you choose but the high ratio rockers give a similar effect by opening the valves further and you can see the benefit from these.

Again, hopefully someone with cam experience can give you a steer - I just went with general engine experience...

Hope that helps...

Certainly does Jimbly thank you. I'm looking at an uprated cam, something like an engle 110 or scat c25/35. What I don't want to do is throw money at things and it not be worth it. I'm all ears for advice and personal experience. :mrgreen:

 

[weeboll]

another agree to not polishing

 

[jonboylaw]

Following this one with interest, lots of photos please Sarah.

BTW, I suggest putting the pushrods through some cardboard with the cylinder numbers marked on it so you do not mix them up, although you are changing the followers I would think so not a biggy.

 

[67panel]

PORTED MEANS OPENING UP AND MATCHING-MILD OR WILD DEPENDS ON APP,POLISHING MEANS SMOOTHING NOT A MIRROR FINISH AS YOU NEED SOME ROUGHNESS TO INDUCE SWIRL,DONT AGREE ON NOT POLISHING EXHAUST COS YOU NEED TO GET GASES OUT SO AS TO CREATE A VACUMN EFFECT TO DRAG INTAKE CHARGE IN AND IF YOU READ UP ON THIS YOU WILL FIND THE EXHAUST IS MORE IMPORTANT THAN THE INTAKE WHEN IT COMES TO MAKING POWER ,MOST OLD SCHOOL ENGINES HAVE VERY POOR EXHAUST FROM THE FACTORY BUT REASONABLE INTAKE.

 

[Merlydog]

So been away for the last week so sorry for the delay! I managed to get it down to the short block yesterday.. Two things I found were the barrels are bloody tight! Rubber mallet required and lots of patience. I used an old camping stove to heat the gudgeon pins which made them MUCH easier to remove. B&Ps look as good as the heads, PO said they were only 6 months old, they do look good but I don't need them so ill move them on. Honing marks were still visible.

So I'm now down to the short block.

The other point of note was the oil pump, it had fairly bad scorch marks into the cover which had in turn damaged the upper cog, made the edges fairly sharp so I'm guessing a new oil pumps in order, or at least cover and upper cog.

 

[Merlydog]

All last week provided dangerous thinking time :shock:

If I port the heads, upgrade the springs etc I might get high 50'sBHP. But..... If I machine the case/heads for 90.5 and add my dellorto's i'll probably get 90BHP (at a push). assuming I stick a decent exhaust on maybe? Cost wise is around £150 extra than if I stayed 'stock' porting. There is the machine shop fook about factor but tbh I rang stateside today and they were great, not put off by a woman doing the work and very easy to chat to. I'm heading down Friday to find out if the case is all ok so we shall see.

Life would be boring without us folk that change our mind a lot!! :lol:

 

[67panel]

thats what I was thinking but didnt say owt cos you allready been there still worth porting the heads ,not for hp but to make it more eficiant = better on fuel.

 

[Merlydog]

So I've removed all the bolts and nuts along the seam and the 6 larger nuts around the cylinders on the right of the case and I'm struggling! I can see a 1mm gap appearing at the pulley end of the engine but now it just won't budge. Have I missed something guys? I'm starting to get PMT with it?!! :evil: :lol:

 

[sparkywig]

Go all the way around again checking for that elusive nut, but don't lever the case halves apart otherwise it'll leak when reassembled.

 

[Merlydog]

Go all the way around again checking for that elusive nut, but don't lever the case halves apart otherwise it'll leak when reassembled.

Defo no nut wig.. It's starting to split pulley end but the flywheel end, particularly the top is solid!

 

[sparkywig]

From memory there's 9x M8 nuts and 1x M8 bolt and the 6 main case nuts.
If it's stuck use a rubber mallet to loosen the crankcase halves and lift the rhs off the lhs. If you haven't got a rubber mallet gently tap the case with a hammer and block of wood around the perimeter of the case. Tap all around, not just in one spot.

 

[Merlydog]

Ok ok so there was a nut :shock: It was caked in ***** though and you really couldn't see it!

Anyway that aside and with the help of my home made case splitter she's in two halves. :mrgreen:

When it popped open and I saw this I thought......

Is that it? :shock:

Here's a few pics but I'm not sure what I'm looking for tbh? Any light much appreciated..

Machine shop Friday