What can i expect ??

[Adam Brown]

Hi all a while ago I posted on here about my decked block after much thought I went down the route of having the pistons machined after loosing out on 2 blocks from eBay.

I'm getting close to completion now and I'm just woundering what kind of performance I can roughly expect out of my engine so HP , fuel economy, 0-60 time in standard escort with mex gearbox single prop and standard back end spec list below: and I'm not racing it's a road car

1700 xflow New everything in terms of seals
1300 +0.090 pistons (raised compression) and turned down 1.6mm
Kent bcf2 fast road cam
Piper dual valve springs
Steel rocker assembly, posts spacers
Port and polished faced and 're-cut valve head but retains gt/mex valve sizes New cam followers bearings all arround
crank ground 0.030 both j
Steel crank pulley
7.5 kg flywheel over the standard 12kg
Duplex dining chain kit
Standard oil pump kn oil filter and magnetic sump plug
Standard fuel pump
Mls head gasket standard thickness
Sportex 4 branch exhaust manifold and single back box
Yamaha r1 bike carbs and manifold with pipercross filter
Standard conrods
Arp studs all round: head, caps and rods
Powerspark ignition kit includes high power coil and magnetic pick up dizzy And ngk 4 point spark plugs
65amp altinator

The next question is since I've had so much machining done is it worth getting everything balanced up as I've been quoted an eye watering 280 +vat for the lot to be balanced up

Also I haven't had the head done for unleaded can I run unleaded fuel or will I need and additive. I was told having seats done was bad news of xflows

[tones61]

140bhp

[Graham]

140bhp

on a bcf2? not a cat in hells chance

[Graham]

without unleaded inserts the exhaust valves will recess into the head over a period of time, but it could be years before you have an issue additive or no additive. fitting inserts is ok for mex/gt valve sizes, but tricky if you go big valve.

power, somewhere between 105 and 120bhp.

balancing, dont bother, in most cases it does nothing

[Adam Brown]

without unleaded inserts the exhaust valves will recess into the head over a period of time, but it could be years before you have an issue additive or no additive. fitting inserts is ok for mex/gt valve sizes, but tricky if you go big valve.

power, somewhere between 105 and 120bhp.

balancing, dont bother, in most cases it does nothing

What's the best kind of cam to run its only a road car? I only put in the bcf2 as I already had one nos in its box from my dad's box of bits. I realisicly want something as powerful as I can get without making it undrivable in traffic I don't want to be revving the nuts off it to get anywhere but I still want it quick any cam recommendations ? I'd rather swap it now while it's still out of the car if there is a better alternative.
Cheers

[Graham]

problem is everyone has a different idea of driveable!

sure theres people who drive on the road with a 244, but that will be utterly gutless unless you rev it, the other end of the scale is a standard cam or a 224, should pull from nothing but wont give you any real top end.

[Adam Brown]

problem is everyone has a different idea of driveable!

sure theres people who drive on the road with a 244, but that will be utterly gutless unless you rev it, the other end of the scale is a standard cam or a 224, should pull from nothing but wont give you any real top end.

I looked online and because my pistons are getting thin on the ground because of the deck taken off I don't want to go down the the route of any more machining on the valve pockets there's a Kent bef3 cam (don't know the equivalent in 2**) an and says in the discription it's the max you can have without machining pockets listated as fast road/rally cam shaft on Burton's

Where as the bcf2 is listed as fast road
I really want to be somewhere in the middle with a power band between 2500 and 6000

[Graham]

a lot of the time the bcf3 DOES need deeper valve cut outs, as does any cam more than a bcf2 ( occasionally even that one does)

[Pushrod King]

a lot of the time the bcf3 DOES need deeper valve cut outs, as does any cam more than a bcf2 ( occasionally even that one does)

I'd say even using a bcf2 will need deeper cut outs with 1.6mm off of the deck height.

[Graham]

I'd say even using a bcf2 will need deeper cut outs with 1.6mm off of the deck height.

your probably right there nick

[Adam Brown]

your probably right there nick

I had them machined back in to standard so matched new pockets to match the new hight to bring the crown back . I'll ask to see if he could go any deeper if so by how much to run what can what's the best all rounder cam. As it stands he still has my pistons so if I'm having it done it wants doing now.

Burton's quoted 0.100 deeper

[Forest_rallying]

When your number one piston is a TDC and the valves for that cylinder are on overlap ie, rocking you need to be able to push the valve into the pocket until it touches the piston by at least 4.5mm to ensure you have enough valve to piston clearance. You may need a light pair of valve springs for this purpose.

Kent quote 2.14 mm @ TDC for the BCF2 and 2.48 mm for the 224. Never take a chance on valve to piston clearance, it just is n't worth it. What depth are the pockets machined to now?

[Adam Brown]

When your number one piston is a TDC and the valves for that cylinder are on overlap ie, rocking you need to be able to push the valve into the pocket until it touches the piston by at least 4.5mm to ensure you have enough valve to piston clearance. You may need a light pair of valve springs for this purpose.

Kent quote 2.14 mm @ TDC for the BCF2 and 2.48 mm for the 224. Never take a chance on valve to piston clearance, it just is n't worth it. What depth are the pockets machined to now?

I had him put them back to standard so the hight of the crown of standard pistons

[Forest_rallying]

I forgot to say on the above valve clearances need to be measured with the valves fully closed to being pushed down into the pocket. You need to deduct the lift at TDC from your overall figure, that'll give you some idea what your clearances are.

I have just had a look what overlap they quote for the BCF3 and 234 cams. 2.48 and 2.84 mm according to Kent's Data.

[Adam Brown]

I forgot to say on the above valve clearances need to be measured with the valves fully closed to being pushed down into the pocket. You need to deduct the lift at TDC from your overall figure, that'll give you some idea what your clearances are.

I have just had a look what overlap they quote for the BCF3 and 234 cams. 2.48 and 2.84 mm according to Kent's Data.

I had the shop put the pistons standard but I've got my own lathe at home so I could turn down the pockets some more Kent quoted
.100". Should I just go ahead and get the shop to take this quoted figure off or do as you say and measure them myself ?

[Graham]

how you going to deepen the pockets in a lathe?

[HonkyWhiteTrash]

I had the shop put the pistons standard but I've got my own lathe at home so I could turn down the pockets some more Kent quoted
.100". Should I just go ahead and get the shop to take this quoted figure off or do as you say and measure them myself ?

If you are able to do some quite complicated offset-hole boring on your lathe then go for it but otherwise I would get a machine shop to do them. Normally done on a miller.

EDIT - I see I was still writing my response while Graham had already posted his!

[Adam Brown]

If you are able to do some quite complicated offset-hole boring on your lathe then go for it but otherwise I would get a machine shop to do them. Normally done on a miller.

EDIT - I see I was still writing my response while Graham had already posted his!

Basically what I'm asking If if the quoted pockets are reliable or are they exsessive or am I better measuring like quoted above ?

[Pushrod King]

Basically what I'm asking If if the quoted pockets are reliable or are they exsessive or am I better measuring like quoted above ?

Always better to dummy build the engine to check clearances and cc up for compression ratio.

[Adam Brown]

I've just had a thought with the block bring skimmed how will this effect pushrod length and how would I correct it ? Would I need diffrent followers or taller valve posts ?

[Graham]

theres a reason why the rockers have adjusters! unless you have had a massive amount taken off the block you do not need to worry about pushrod length

[onecamohv]

how you going to deepen the pockets in a lathe?

I did a set of xflow pistons in my lathe few months ago, alot of time setting up but once done worked out great. I Mounted the pistons by machining a bar the same dia as the wrist pin and mounting it on the faceplate. Finding the center point of the valve is the hardest part. If you can dummy build the engine and use an old valve sharpened as a punch to mark the piston it would save hours