Building my first engine. got some newbie questions!
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littleyellerghia
- Posts: 2
- Joined: Sat Feb 27, 2016 6:31 am
Building my first engine. got some newbie questions!
Hey everyone, new guy to the site here! Im looking to put together a 1915 for my 71 ghia. Im on a budget, but not hesitant to spend money in the right places. So I had a few questions when i go to have the machine work done and whatnot. Are the factory heads any good? How do i tell which ones i have? Its an AE block thats in the car (with nothing done to it) so im assuming it has the original heads on it also. What size valves should I run? The cam im looking at is the Engle w110. I have a set of weber 44 carbs for it,ceramic coated hi flow heater boxes and exhaust,009 distributor,and a scat pulley. Any other pieces of advice or things i should or buy for it? thanks alot guys!
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Marc
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- Joined: Thu May 23, 2002 12:01 am
Re: Building my first engine. got some newbie questions!
There should be a casting number in the rockerbox floor which will tell us the vintage of the heads.
What kind of RPM do you expect to turn? That's enough cam to take you past the safe limit for a non-counterweighted crank. Above 5,000 RPM or so they start to flex and pound out the case.
If you'll be running a CW crank, ideally you'd step up the valve sizes to 40x36 (stock is 35.5x32) but with a stock crank I see no point in it.
However you go on the crank, it needs to be 8-dowelled to the flywheel or they'll part company (usually destroying both in the process). You may want to run a lighter flywheel, although I wouldn't recommend getting carried away in a relatively heavy car...say, ~15-16lbs with a stock crank, 12-14lbs with a CW crank.
Will you be getting the case align-bored for oversize-O.D. main bearings? Ask the shop if they have the tool for cutting the center cam web out to standard size; if they do, have that done at the same time...it should only add $10-$15. High-mileage cases tend to get a little pounded/warped there, making the clearance too tight on the center cam bearing. If they don't have the tool and the case needs it, the alternative is hand-scraping the bearing shells until you get the correct clearance. That's free if you do it yourself, but can be time-consuming (well worth paying the $15 for the bore IMO).
Intake porting helps make more power; if you can't pay a pro to do it, you shouldn't get into any trouble with a DIY "mini-D" job.
The W-110 cam should really have heavy duty valve springs (it's possible to get away with stock ones up to ~4500 RPM or so, but I wouldn't advise it). Regardless, you should install steel shims under the springs. Most machine shops will only do this for the ones which needed more seatwork in order to even the installed heights of the springs, but they also prevent the springs from chewing into the heads - rarely an issue on a stock engine, but when you start thrashing it and floating valves it happens.
You'll also want to invest in a set of "solid" rockershafts so you can get rid of the stock wavy washers & spring clips - they tend to break when you start using some revs.
I would run CrMo pushrods, or if they're in the budget the HD aluminum ones such as aircooled.net sells. Again, some folks have gotten away with stock pushrods with the 110 but it's sketchy.
You may need custom-length pushrods. There are many variables which affect rockerarm geometry so it's impossible to predict, you don't find out until the heads are back on. Don't be surprised if you have to put the project on hold while getting some, or "universal" ones which need to be cut to length. Good time to clean & paint the engine sheetmetal
Stock valve adjusting screws are adequate for the 110, but many prefer to install "swivelfoot" adjusters. Doing this right, so you don't screw up the rockerarm geometry, adds a lot more time to the build than you might think (typically the rockerarms need grinding for clearance, simply throwing shims under the rocker assemblies may let you adjust the valves but it can hose the geometry - the parts-sellers never mention that).
Starting in `71 with the AE cases, the top-front headstud on #3 got anchored more deeply in the case. This is a good thing, since it lessens the incidence of the case cracking along the front there. Since the case needs to be bored out to the max for "normal" 94s this is even more important. Personally I prefer to have the case opened up to the "90.5/92" dimension and have the cylinder skirts turned down to match, but that does add maybe $60 to the build.
AE cases were cast from a decent alloy, but after 45+ years of service I wouldn't trust the head studs being screwed directly into the case as they were from the factory for a higher-performance engine. They need to be pulled for the machinework, it's the ideal time to go ahead and have the holes drilled/tapped for steel thread inserts (A.K.A. "case-savers"). If that hasn't been done yet, I'd recommend that you do it. The inserts come in several different outer thread sizes. You want the smallest ones, made by Time-Sert, which are m12x1.5. Bigger-O.D. ones will be a problem when the case is opened up for the larger cylinders. Some shops will take a shortcut and put the insert for that top-front stud I mentioned in flush, since it's difficult to do properly...bad move, you'd be better off just leaving that hole as-is with no insert. When the case is cut out for 94s (and sometimes even "just" for 92s) it removes most of the ring in the casting that the cylinder sits on, so the case must then be "decked" (machined to establish a wide enough seating surface for the cylinders). Case-savers must be installed below flush (or at minimum, flush), so the cylinder doesn't hit them and fail to seat squarely. Some machinists just do the decking first, but they have cutters for their mill which can handle cutting magnesium and steel at the same time.
That should be enough for you to chew on for a little while.
What kind of RPM do you expect to turn? That's enough cam to take you past the safe limit for a non-counterweighted crank. Above 5,000 RPM or so they start to flex and pound out the case.
If you'll be running a CW crank, ideally you'd step up the valve sizes to 40x36 (stock is 35.5x32) but with a stock crank I see no point in it.
However you go on the crank, it needs to be 8-dowelled to the flywheel or they'll part company (usually destroying both in the process). You may want to run a lighter flywheel, although I wouldn't recommend getting carried away in a relatively heavy car...say, ~15-16lbs with a stock crank, 12-14lbs with a CW crank.
Will you be getting the case align-bored for oversize-O.D. main bearings? Ask the shop if they have the tool for cutting the center cam web out to standard size; if they do, have that done at the same time...it should only add $10-$15. High-mileage cases tend to get a little pounded/warped there, making the clearance too tight on the center cam bearing. If they don't have the tool and the case needs it, the alternative is hand-scraping the bearing shells until you get the correct clearance. That's free if you do it yourself, but can be time-consuming (well worth paying the $15 for the bore IMO).
Intake porting helps make more power; if you can't pay a pro to do it, you shouldn't get into any trouble with a DIY "mini-D" job.
The W-110 cam should really have heavy duty valve springs (it's possible to get away with stock ones up to ~4500 RPM or so, but I wouldn't advise it). Regardless, you should install steel shims under the springs. Most machine shops will only do this for the ones which needed more seatwork in order to even the installed heights of the springs, but they also prevent the springs from chewing into the heads - rarely an issue on a stock engine, but when you start thrashing it and floating valves it happens.
You'll also want to invest in a set of "solid" rockershafts so you can get rid of the stock wavy washers & spring clips - they tend to break when you start using some revs.
I would run CrMo pushrods, or if they're in the budget the HD aluminum ones such as aircooled.net sells. Again, some folks have gotten away with stock pushrods with the 110 but it's sketchy.
You may need custom-length pushrods. There are many variables which affect rockerarm geometry so it's impossible to predict, you don't find out until the heads are back on. Don't be surprised if you have to put the project on hold while getting some, or "universal" ones which need to be cut to length. Good time to clean & paint the engine sheetmetal
Stock valve adjusting screws are adequate for the 110, but many prefer to install "swivelfoot" adjusters. Doing this right, so you don't screw up the rockerarm geometry, adds a lot more time to the build than you might think (typically the rockerarms need grinding for clearance, simply throwing shims under the rocker assemblies may let you adjust the valves but it can hose the geometry - the parts-sellers never mention that).
Starting in `71 with the AE cases, the top-front headstud on #3 got anchored more deeply in the case. This is a good thing, since it lessens the incidence of the case cracking along the front there. Since the case needs to be bored out to the max for "normal" 94s this is even more important. Personally I prefer to have the case opened up to the "90.5/92" dimension and have the cylinder skirts turned down to match, but that does add maybe $60 to the build.
AE cases were cast from a decent alloy, but after 45+ years of service I wouldn't trust the head studs being screwed directly into the case as they were from the factory for a higher-performance engine. They need to be pulled for the machinework, it's the ideal time to go ahead and have the holes drilled/tapped for steel thread inserts (A.K.A. "case-savers"). If that hasn't been done yet, I'd recommend that you do it. The inserts come in several different outer thread sizes. You want the smallest ones, made by Time-Sert, which are m12x1.5. Bigger-O.D. ones will be a problem when the case is opened up for the larger cylinders. Some shops will take a shortcut and put the insert for that top-front stud I mentioned in flush, since it's difficult to do properly...bad move, you'd be better off just leaving that hole as-is with no insert. When the case is cut out for 94s (and sometimes even "just" for 92s) it removes most of the ring in the casting that the cylinder sits on, so the case must then be "decked" (machined to establish a wide enough seating surface for the cylinders). Case-savers must be installed below flush (or at minimum, flush), so the cylinder doesn't hit them and fail to seat squarely. Some machinists just do the decking first, but they have cutters for their mill which can handle cutting magnesium and steel at the same time.
That should be enough for you to chew on for a little while.
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littleyellerghia
- Posts: 2
- Joined: Sat Feb 27, 2016 6:31 am
Re: Building my first engine. got some newbie questions!
Wow thanks for the info! i was thinking about using the stock crank because it wont be seeing that high of rpms. That give me a way better perspective on the build. Ive done Small and big block mopars and a ls1 engine,but never a vw. Thanks again for the advice!
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Marc
- Moderator
- Posts: 23741
- Joined: Thu May 23, 2002 12:01 am
Re: Building my first engine. got some newbie questions!
With the stock crank I wouldn't bother with big-valve heads. NEW stock valve springs shimmed an extra .030-.060" should be sufficient if you decide to try running stock pushrods, but personally I'd use some entry-level HD singles and CrMo p'rods.
It'd be worth doing a little intake port work (be sure to port-match the manifolds). If you're timid about this, just open 'em up to the I.D. of the stock sheetmetal gasket and blend, but raising the roof helps.
Your cam/carbs will still be coming on strong at 5,000. There are rev-limiting distributor rotors which'll fit many VW distributors available for ~$25. One rated for 5400 RPM max would be smart.
You may be able to get away with the stock rocker shafts (for a while) but I recommend against it.
If you take nothing else away from this, DO get the crank & flywheel 8-doweled unless you think you'll always launch like grandma. Your 1915 will make more torque than the stock 4 can take if abused (I've shed a 'wheel from a mild 1679)
A larger-diameter glandnut washer would be wise, too. These are also thicker than stock so you lose a little thread engagement unless the head of the glandnut is undercut. That's not a biggie but be sure to check that there's enough clearance between the glandnut and disk center to allow for clutch wear or you'll end up with drag.
http://www.thesamba.com/vw/classifieds/ ... id=1429285
It'd be worth doing a little intake port work (be sure to port-match the manifolds). If you're timid about this, just open 'em up to the I.D. of the stock sheetmetal gasket and blend, but raising the roof helps.
Your cam/carbs will still be coming on strong at 5,000. There are rev-limiting distributor rotors which'll fit many VW distributors available for ~$25. One rated for 5400 RPM max would be smart.
You may be able to get away with the stock rocker shafts (for a while) but I recommend against it.
If you take nothing else away from this, DO get the crank & flywheel 8-doweled unless you think you'll always launch like grandma. Your 1915 will make more torque than the stock 4 can take if abused (I've shed a 'wheel from a mild 1679)
A larger-diameter glandnut washer would be wise, too. These are also thicker than stock so you lose a little thread engagement unless the head of the glandnut is undercut. That's not a biggie but be sure to check that there's enough clearance between the glandnut and disk center to allow for clutch wear or you'll end up with drag.http://www.thesamba.com/vw/classifieds/ ... id=1429285
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FJCamper
- Moderator
- Posts: 2910
- Joined: Wed Nov 14, 2007 2:19 pm
Re: Building my first engine. got some newbie questions!
Hi LittleyellerGhia,
And welcome to the VW world. Here's some info.
Our RetroRacing Endurance Superbug
https://www.youtube.com/watch?v=zvYgzPgBRaw
Ghia Roadcourse handllng tutorial
http://www.shoptalkforums.com/viewtopic ... 1&t=127619
and just for fun, Little Karmann Coupe by the Beach Boys
http://www.youtube.com/watch?v=g-nxYy6HEX0
FJC
And welcome to the VW world. Here's some info.
Our RetroRacing Endurance Superbug
https://www.youtube.com/watch?v=zvYgzPgBRaw
Ghia Roadcourse handllng tutorial
http://www.shoptalkforums.com/viewtopic ... 1&t=127619
and just for fun, Little Karmann Coupe by the Beach Boys
http://www.youtube.com/watch?v=g-nxYy6HEX0
FJC