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Thu Sep 06, 2012 8:28 pm

as post says, what is the safest engine size I could build with this case? I understand the small oil passages. Would a 1776 be too large? My plan is to keep it a modest daily, with doghouse setup, 110 cam, reworked stock heads, full flowed, Scat 35 pdsit kit (got them years ago), 1 3/8 header with heater boxes. This engine is absolutely tired as hell and needs some major help. I wasnt planning on having this engine be this bad...dont have the dough to really do it the way I want right now. Have another baby coming in a few months as well. I am really on a budget, basically need to do this as cheap as I can and I already have most of the external parts needed.

Any help would be great, guys! Thanks

Thu Sep 06, 2012 9:07 pm

For any single relief small oil passage cases the most they should be is a 1600. Rpm is the killer of internals in these engines so also keep the cam mild, no larger than a W100.

People will tell you you can go bigger (you can and I have) but for a reliable long lasting build keep it a low revving stocker and save up for a good case to build a performance engine on.

Thu Sep 06, 2012 9:26 pm

DO NOT spend any money on this F case. Conventional wisdom ? is that the case is weak and the cylinder studs will pull out. Case savers would be an absolute must to use this case. It is also likely to be pretty old, so the crankshaft bore may be pounded out, absolutely requiring a line bore. I would NOT take this case beyond 1600cc, which requires boring of the case for the new cylinders and a different set of heads. The heads on your case, if original, have small valves, and would have to bored out to accept even the 1600 barrels and pistons. Lightly used or rebuilt 1600 heads should be readily available. Trying to hop this case up will likely result in a short engine life.

Before you do anything, assuming the F engine is still in one running piece, measure the crankshaft end play and get compression readings. That is to give you an idea of the current state of the engine, even though you already think it is sad. They will likely not be too good, lending to the "do not rebuild this case" idea.

If you are really on a budget look around for a used B or later case running engine. Do not even think of buying it until you measure crankshaft end-play (specified maximum .006" but adjustable with flywheel shims if it's not to bad). Also, get compression readings before you buy. A 1971 or later engine will be even better - it's somewhat newer, has bigger oil passages, and has offset oil cooler. It originally came with dual port heads. Put your extractor exhaust on the "new" used engine, and smile while you're driving it. A nice hop-up for this used engine would also be a pair of weber 34ict carbs. I would also install an oil filter.

If you're determined to build a hopped up engine, try not to do it on anything earlier than a 1971 engine case. The 1776cc and 110 cam is good. If around town (and NOT participating in stop light grand prix racing because you're a family man) the W100 cam will be beneficial and more likely to pass the ?"&*^%$# emissions requirements. This engine will benefit from dual carbs such as kadrons or the 34 ict's. Hopefully for your budget you can find a used pair of those. Yes, people that aren't spending your money will tell you to get bigger dual webers.

Good luck. Let us know what you do.

Thu Sep 06, 2012 9:29 pm

If you search back through RC's posts, he talked about enlarging the oil passages of single relief cases for mild performance builds. No reason why you couldn't do a 1776 with the parts you have. As mentioned, the 1300 heads have small valves so 1600 heads would be worthwhile.

Thu Sep 06, 2012 9:35 pm

P. S. The 35pdsit carbs are relatively low performance carbs, but have the advantage of having chokes for starting.

Owing to small valve size don't bother with your original heads (assuming your have stock heads on the F engine).

I suggest a good used engine because it is likely to be more budget-friendly than an engine rebuild,

Thu Sep 06, 2012 10:12 pm

I'll second third and fourth what the others have said here - don't 'grow' an F based motor - and I'll throw in the H case (H0 and H5) too as there really is no meaningful differences. Due to the stresses put on the oiling system to help cool a larger motor and the small oil passages I'd recommend the H and F cases be built to 1600 tops. Add a DP 35mm fan to help keep it cool. Throw in a doghouse cooler - might help.

I've rebuilt many F and H case motors - seems at least one head stud came loose on every one of those bastards! Sometimes more. I had a goodly supply of self tapping head studs (not recommending them!) on hand for just that purpose. IMO the expense of putting case savers in F and H cases are a waste unless you have a very pristine case - something I haven't seen many of in 40 years of building ACVW motors. They just don't last even in stock form.

A 68 I bought in 72 had 70k miles when I bought it. It was making a thudding noise - I knew what it was - at least one loose head stud and maybe more - the head was lifting. I pulled that motor and installed a 71 DP motor almost immediately. I was going to rebuild the 1500 SP but it was pounded out so badly that I decided not to. It was junk after only 70k miles. the 3-4 head was cracked beyond repair. I suspect the PO had overheated it badly. I salvaged the crank - one head - tin - and little else.

Look around your area - someone somewhere near you has a good AD AE A(whatever) case. Don't reject a type III case - they can be modified for a beetle very easily. The beetle case cannot be similarly utilized for the type III.

Thu Sep 06, 2012 11:56 pm

an F case is a million times better than an H5 case, which have their own set of issues

if it checks out ok dimensionally, I'd build a mild single port 1600

Fri Sep 07, 2012 8:10 am

When I got this motor (came with bus), PO said it was a good motor and never let him down. Said it was a 1600 and felt stronger than most 1600s he had driven. I think not! I knew the second I got in and drove, it was gutless and not a 1600 to begin with. I think someone just put dp heads on a 1300. He didnt even have holes in the breastplate blocked and the fan shroud was dumping air out into the compartment. I got it back to Utah and installed proper tins, converted it to doghouse setup, installed my old 35 pdsits (rebuilt and dialed in with correct jetting and fuel pressure), better exhaust system ( 1 3/8 header with a muffler) and some 1 3/8" Js for now, replaced a bunch of seals and parts on the engine...to no avail. Engine is still a gutless POS I cant even drive down the road because of overheating and lack of much needed power, here among Utah drivers! I have done a lot of performance stuff before, just not had experience with a case this old.

From what Ive read, it probably isnt worth my time to mess with this thing. I think I am going to have to source a better case and not patch this POS together. Damnit!!

Fri Sep 07, 2012 8:29 am

smitty24 wrote: When I got this motor (came with bus), PO said it was a good motor and never let him down. Said it was a 1600 and felt stronger than most 1600s he had driven. I think not! I knew the second I got in and drove, it was gutless and not a 1600 to begin with. I think someone just put dp heads on a 1300. He didnt even have holes in the breastplate blocked and the fan shroud was dumping air out into the compartment. I got it back to Utah and installed proper tins, converted it to doghouse setup, installed my old 35 pdsits (rebuilt and dialed in with correct jetting and fuel pressure), better exhaust system ( 1 3/8 header with a muffler) and some 1 3/8" Js for now, replaced a bunch of seals and parts on the engine...to no avail. Engine is still a gutless POS I cant even drive down the road because of overheating and lack of much needed power, here among Utah drivers! I have done a lot of performance stuff before, just not had experience with a case this old.

From what Ive read, it probably isnt worth my time to mess with this thing. I think I am going to have to source a better case and not patch this POS together. Damnit!!

Sounds like this particular engine is toast. a 1300 in a bus will be gutless, but if it is in decent shape it should not overheat just like that, not even when it is hauling more weight.
The problem with an F case is not limited by CC´s for that matter. It is, as menthioned a somewhat underdimensioned oil supply system. The enlargement of the main gallery and supply routing from the oil pump makes a vast difference to pressure stability, even with a stock 21 mm oil pump. However, I do like to swop to a 26 mm when I´m at it. But you need to pay attention to the pressure relief system then (another story) or the ol pressure will have a tendency to stay elevated also when the engine reaches running temps. I have never had a bearing failiure on an engine with this mod.
If it is one of the last f cases it is already dual relief.

T

Fri Sep 07, 2012 8:42 am

so it's setteled Ill use an 82 stroke in one of these old cases with enlarged gallys&extra gallys&case savors&larger pickup tube.and see how it all works out.you just cant get any better than a oe vw case....or so I have been told.

Fri Sep 07, 2012 9:34 am

mark tucker wrote: so it's setteled Ill use an 82 stroke in one of these old cases with enlarged gallys&extra gallys&case savors&larger pickup tube.and see how it all works out.you just cant get any better than a oe vw case....or so I have been told.
As long as you keep revs below 6 grand I see no problem with it. I failed to write that in the previus post.

"The problem with an F case is not limited by CC´s for that matter. RPM is" as long as you keep revs to 5500, - 6000 tops I see no problem with that.
:wink:
T

Fri Sep 07, 2012 9:54 am

I have my F-series 1300 stored on a shelf in my garage in turn-key configuration just in case I ever want to make my '66 ghia stock again.

Fri Sep 07, 2012 10:59 am

Does anyone have a link to the oil galley mods? Is is something that MUST be done at a machine shop?

Fri Sep 07, 2012 2:14 pm

what does rpm have to do with it??unless you let bubba balance it in the corrner on a bannanna

Fri Sep 07, 2012 10:00 pm

Alstrup wrote: you need to pay attention to the pressure relief system then (another story) or the ol pressure will have a tendency to stay elevated also when the engine reaches running temps. I have never had a bearing failiure on an engine with this mod.

what mods to the relief system are you talking about?