Since the days are getting shorter and the nights drawing in (notwithstanding the gorgeous weather we've been having lately), my thoughts have turned back to the engine stuck at the back of the garage looking miserable. This is where work stopped midway through the year:
The block is stripped and the main caps have been put back on so that they can be checked properly.
The next stage is to give the block to an engine rebuilding engineering shop and give them a list of stuff to do. I was searching about for one of these when I came across this site: http://www.trevor-turner.co.uk/V8rebuild.htm. In there this guy uses an engine rebuilder called Graham Wellstead Engines. I gave them a call, and although Graham Wellstead has moved on, the same guys bought the business up and are still going. They're now called Modus [http://www.modusengineservices.co.uk/index.html] and appear to be a K-Series specialist. Even so, I had a chat with them and they seemed very sure they could handle what I needed doing, and they sounded confident without sounding like they were blagging it. So, what do I need doing?
Overall:
Check block for cracks and anything else that would write the block off.
Remove core plugs
Clean it!
Bores:
Check bore surfaces/taper and rebore to next size if necessary (i.e. if surfaces are poor/worn badly or bore tapers > .011", otherwise hone at current size. If there are a couple/few that are bad, but most are OK with just honing, then line the bad ones and rebore bad to +40 thou and hone to match others.
Decks:
Mill .005" off each deck. If decks are true and waterways OK, then leave there, else take another .005" off, should be OK after that.
Block:
Tap for screw in oil plugs
Cam bearings
Remove old, install new, taking care to match oil holes up on bearing No.1.
Camshaft
If camshaft needs a 7/16" bolt for the retainer, drill and tap for this.
Interestingly to install the cam bearings (or at least to check them) the machine shop said they'd need me to take the camshaft along to them. I wasn't really ready to buy the camshaft yet, as I'm trying to build up slowly and not cost myself big chunks of wedge at any one time. So I didn't really want to pay for the machining of the block and lash out for the cam.
On the cam selection, I needed to make some decisions. Because my block was never fitted with a roller cam, I either have to use a flat tappet camshaft (which does mean you need to be careful with ramp acceleration - how aggressively the valves come up to full lift) which is the cheap option, or, use a retro fit hydraulic roller cam which doesn't have the limitation of the ramp acceleration, but does mean that the revs are limited somewhat because the hydraulics can 'pump up' which means the valves don't close properly. These retro cams are also expensive. Given that I want the engine to be in some way civilised, but still have plenty of mid-top end power (say max power at about 6000 rpm, redline at 6750-ish) I can run a hydraulic lifter with full roller, so I opted for a Comp Cams 290HR grind. Here's a vid of someone running the same cam in a stroked version of the 351 Clevland engine which is a close relative of mine http://www.youtube.com/watch?v=BctSI8OkULE. You can see/hear that the idle is pretty lumpy, however, I'm hoping to smooth this somewhat as I'm using EFI and this guy is using a carb. Even if mine doesn't idle silky smooth, I don't really mind a little chop :).
Here are the cam specs:
You can see that standard lift on this cam is .544". This is with the standard 1.6 ratio rockers . I'm going to sneak a bit more lift by using 1.7 ratio rockers, which will give me a lift of .578", which doesn't sound like much of an increase (6.25%), but is actually about the increase in lift between a pretty mild cam and a pretty wild one. Because the duration will remain the same, I think I should be a winner on a tad more power for no difference in driveability. I was a bit worried that with this hydraulic retro fit thing I was heading for a bit of a compromise. It appears that I should still be looking at good power once the engine is all built up:
This is from the Real Steel catalogue (this is where I bought the cam from). You can see that they built a 347 stroker using this cam and they claim 440bhp on their dyno. Even allowing for a pretty sizeable bullshit factor (which they're not known for, to be fair), that's a pretty decent output. Interesting that this cam means the firing order needs to change from the 302 style to the 351 style. As posted before, this makes no difference to the exhaust tuning.
Cam should arrive tomorrow.
The block is stripped and the main caps have been put back on so that they can be checked properly.
The next stage is to give the block to an engine rebuilding engineering shop and give them a list of stuff to do. I was searching about for one of these when I came across this site: http://www.trevor-turner.co.uk/V8rebuild.htm. In there this guy uses an engine rebuilder called Graham Wellstead Engines. I gave them a call, and although Graham Wellstead has moved on, the same guys bought the business up and are still going. They're now called Modus [http://www.modusengineservices.co.uk/index.html] and appear to be a K-Series specialist. Even so, I had a chat with them and they seemed very sure they could handle what I needed doing, and they sounded confident without sounding like they were blagging it. So, what do I need doing?
Overall:
Check block for cracks and anything else that would write the block off.
Remove core plugs
Clean it!
Bores:
Check bore surfaces/taper and rebore to next size if necessary (i.e. if surfaces are poor/worn badly or bore tapers > .011", otherwise hone at current size. If there are a couple/few that are bad, but most are OK with just honing, then line the bad ones and rebore bad to +40 thou and hone to match others.
Decks:
Mill .005" off each deck. If decks are true and waterways OK, then leave there, else take another .005" off, should be OK after that.
Block:
Tap for screw in oil plugs
Cam bearings
Remove old, install new, taking care to match oil holes up on bearing No.1.
Camshaft
If camshaft needs a 7/16" bolt for the retainer, drill and tap for this.
Interestingly to install the cam bearings (or at least to check them) the machine shop said they'd need me to take the camshaft along to them. I wasn't really ready to buy the camshaft yet, as I'm trying to build up slowly and not cost myself big chunks of wedge at any one time. So I didn't really want to pay for the machining of the block and lash out for the cam.
On the cam selection, I needed to make some decisions. Because my block was never fitted with a roller cam, I either have to use a flat tappet camshaft (which does mean you need to be careful with ramp acceleration - how aggressively the valves come up to full lift) which is the cheap option, or, use a retro fit hydraulic roller cam which doesn't have the limitation of the ramp acceleration, but does mean that the revs are limited somewhat because the hydraulics can 'pump up' which means the valves don't close properly. These retro cams are also expensive. Given that I want the engine to be in some way civilised, but still have plenty of mid-top end power (say max power at about 6000 rpm, redline at 6750-ish) I can run a hydraulic lifter with full roller, so I opted for a Comp Cams 290HR grind. Here's a vid of someone running the same cam in a stroked version of the 351 Clevland engine which is a close relative of mine http://www.youtube.com/watch?v=BctSI8OkULE. You can see/hear that the idle is pretty lumpy, however, I'm hoping to smooth this somewhat as I'm using EFI and this guy is using a carb. Even if mine doesn't idle silky smooth, I don't really mind a little chop :).
Here are the cam specs:
You can see that standard lift on this cam is .544". This is with the standard 1.6 ratio rockers . I'm going to sneak a bit more lift by using 1.7 ratio rockers, which will give me a lift of .578", which doesn't sound like much of an increase (6.25%), but is actually about the increase in lift between a pretty mild cam and a pretty wild one. Because the duration will remain the same, I think I should be a winner on a tad more power for no difference in driveability. I was a bit worried that with this hydraulic retro fit thing I was heading for a bit of a compromise. It appears that I should still be looking at good power once the engine is all built up:
This is from the Real Steel catalogue (this is where I bought the cam from). You can see that they built a 347 stroker using this cam and they claim 440bhp on their dyno. Even allowing for a pretty sizeable bullshit factor (which they're not known for, to be fair), that's a pretty decent output. Interesting that this cam means the firing order needs to change from the 302 style to the 351 style. As posted before, this makes no difference to the exhaust tuning.
Cam should arrive tomorrow.
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