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Wed Jul 25, 2018 4:16 pm

Hello again!

The body/chassis is at the body shop so I'm rebuilding the engine while I wait. I have rebuilt many of these engines, having worked as a machinist for T.Hoff Inc. machine shop in Raleigh, NC in the 90's. I'm going stock; PICT 34, SVDA, OE profile cam (I guess), full weight flywheel. It's an AE block in good shape. It's just that the whole damn thing has worn out. No abuse, cheap rebuilds or neglect.

I'm looking at AA Performance Products for a comprehensive 1641cc or 1688cc kit. Is this a decent company? Am I missing anything? I have a very competent and willing engine shop in town for anything I need.

Wed Jul 25, 2018 5:32 pm

Hey Kerry.

Super fun to build your own engine. You will not save any money but will have a blast completing the task!

The AE case is a great case (not block) to build off of.

If it were I.....I would have the engine dynamically balanced. This makes a huge difference in the feel of the car and in the life of the bearings!

Good time to get an oil filter in the system. Look into full flowing the case. You having been a machinist will make this task way easier. Tap and plug the oil pump outlet. Pull the oil galley plug on drivers side, rear of case next to the pulley, the big one between the two smaller ones. It is the junction from the oil pump output to the main bearing, lifter bore. Again, super easy to do. I think it is a 3/8 NPT tap. The plus is the oil filter will help save those internal moving components.

I was taught, very early, that the VW engine is one of the best air pumps designed. It has a huge problem though. It has a restriction in the breathing system, the valves are super tiny! If you want to have a better running engine, bigger barrels and cylinders will do the job, but you are trying to flow more through the same tiny valves. Well worth the money to get a set of heads with 40mm intakes and 35mm exhaust. AA has them, sold as a set. Fair price.

Warning! Once you start down the road of minor engine mods, you immediately understand the hidden potential and may end up wanting something better (bigger engine size). That leads to a broken tranny, so then you have to build a better tranny. Not sure where that is going to lead, but I am sure I will post something about it when I get to that point!

Be careful, going forwards!!!!

Thu Jul 26, 2018 3:02 am

Are the 1688s slip in or do you have to bore the case and heads? If they are slip ins, don't do it, unless you like excessive blow by, over heating and a short life span. The gains aren't worth the hassle.

Thu Jul 26, 2018 4:15 am

Jim,

Thanks. Balancing is easily done. I'll look into the full flow mod. I never performed a full flow modification before. We just built stock DP & SP engines and let the buyer do their own mods. Sounds simple enough.

Are you recommending 40/35 heads even with a stock PICT 34 and intake? There's that much flow restriction in the heads?

Multi69's,

You just brought up an old memory; The "slip in 1688" is the one with those thin-walled 90.5mm jugs, isn't it?

I still want to know if anybody has had any experience with AA Performance Products? The engine kits look good and the prices are nice.

Thu Jul 26, 2018 6:28 am

AA's are fine. There are plenty of people using them now. I have been running 20lbs of boost on my 90.5mm p/c's for a bit now. Just check the ring gaps and balance them out of the box.

Thu Jul 26, 2018 7:46 am

Duped post

Thu Jul 26, 2018 8:16 am

Away from the scene for quite a while, so ...... behold this very handy bore/stroke/displacement chart:
http://www.midsouthvw.com/TechTips/Bore-Stroke-Disp.pdf

Check TS archives for info on FFF mods. Best done using at least a large drill press, & a vertical mill is even better.

Hate 'em, tolerate 'em, whatever - that asian giant has stepped-up, discovered the concept of quality/integrity/tolerance & is now producing useful components (at least the easy stuff :P)

Thu Jul 26, 2018 8:30 am

Kerry Chadderton wrote: Jim,

Thanks. Balancing is easily done. I'll look into the full flow mod. I never performed a full flow modification before. We just built stock DP & SP engines and let the buyer do their own mods. Sounds simple enough.

Are you recommending 40/35 heads even with a stock PICT 34 and intake? There's that much flow restriction in the heads?

Multi69's,

You just brought up an old memory; The "slip in 1688" is the one with those thin-walled 90.5mm jugs, isn't it?

I still want to know if anybody has had any experience with AA Performance Products? The engine kits look good and the prices are nice.

The 1688cc are actually VERY thin walled 88mm. You do not want these for any type of longevity. What happens with any thin walled cylinder is they distort when the engine gets hot. Its not a permanent distortion, but after a little wear (which is normal), the cylinders loose their structural integrity and the rings can not maintain a good seal with the cylinders. This leads to excessive blow by which in turn heats the engine oil. I'm dating myself, but back when dirt bikes were air cooled, they estimated that by the end of a race, the engines were losing 30% of their HP due to this same phenomenon. That's why they went to water cooling. Personally, I don't like any of the slip in big bore kits, even the 1641s (87mm) will do this.

As far as the heads, a little bit of cleanup porting is all you would need at the most, especially if you are running the stock cam and carb. In fact you can have a very snappy little engine with well ported stock heads, a mild cam like a 100 or C25, in a 1776. Bigger is not always better, the most important aspect of the intake system is air velocity. Bigger valves and carbs will give you more top end, but you loose air velocity at low RPMs, so you loose the punch, like when accelerating out of a corner.

Thu Jul 26, 2018 8:48 am

Strongly suggest doing some research on vw engine building. There are many authors of great information out there. Each one is great in some way, but they all have their own path and many times discount the greatness others have found.

It is all experience based. We all try a combo, tweaking some item in the setup and extract info from running it. Air velocity is one of those items that is easily thrown around, but many do not fully understand. It is based off of the physics of mass times acceleration equals force. M x A = F. The acceleration is lessened by the volume of air entering through the valve, thus reducing the force of the new charge to push the exhaust out of the cylinder during valve overlap. There are several answers for the riddle. More overlap? Smaller valves? Porting? Polishing?

Bottom line is give yourself an education. Take a leap of faith and burn rubber!

Oh, and have fun doing it!

Thu Jul 26, 2018 9:26 am

VW_Jimbo wrote: Strongly suggest doing some research on vw engine building. There are many authors of great information out there. Each one is great in some way, but they all have their own path and many times discount the greatness others have found.

It is all experience based. We all try a combo, tweaking some item in the setup and extract info from running it. Air velocity is one of those items that is easily thrown around, but many do not fully understand. It is based off of the physics of mass times acceleration equals force. M x A = F. The acceleration is lessened by the volume of air entering through the valve, thus reducing the force of the new charge to push the exhaust out of the cylinder during valve overlap. There are several answers for the riddle. More overlap? Smaller valves? Porting? Polishing?

Bottom line is give yourself an education. Take a leap of faith and burn rubber!

Oh, and have fun doing it!

Now we're going to give the poor guy a headache. Let's really mess with him and talk about fuel droplets sticking to the port walls :D .

But really what he just said is true, If you are sticking stock or close to it, research the quality of the parts. If you start modifying research the people who are giving you advice. Especially check to see if they have any build examples. Remember, this is the internet, and anyone can say anything on it. As far as the AA P&Cs, I've never used them, I usually go with Mahle.

Thu Jul 26, 2018 9:33 am

I used a set of pistons and cylinders from AA when I rebuilt my 1600 (as a 1600) and a year later it is still running great.

Thu Jul 26, 2018 11:06 am

You know guys, all of you are right and have helped me think it through. I can certainly get too far down the rabbit hole if I allow myself. I'm going to stick with stock; displacement, carb, distributor, heads, etc., etc.

I will balance it, full flow the case, electronic ignition and double check everything going in. The ambiguous "Blueprinting", as it were. That will be fine for a young girl to drive (this is a present for my niece). Besides, I have another 1600 long block here if I want to play.

One more question: I'm going to buy a complete engine kit from AA. For literally dollars I can upgrade to a counter-weighted crank. Is it worth it in your opinion? Is it that much smoother?

Thu Jul 26, 2018 12:30 pm

Kerry Chadderton wrote: For literally dollars I can upgrade to a counter-weighted crank. Is it worth it in your opinion? Is it that much smoother?
I think the counter weighted cranks are useful to help get you above 5000rpm. In a stock 1600, with stock heads and valve springs, you don't need it. I would suggest using a balanced german crank, or at the least, ensure the crank that comes in the kit is balanced.

Thu Jul 26, 2018 12:37 pm

First determine if the original crank is serviceable. If not, just fork-over the few extra shekels.
Counterweights help w/ case longevity as well.

Thu Jul 26, 2018 7:48 pm

Kerry Chadderton wrote: You know guys, all of you are right and have helped me think it through. I can certainly get too far down the rabbit hole if I allow myself. I'm going to stick with stock; displacement, carb, distributor, heads, etc., etc.

I will balance it, full flow the case, electronic ignition and double check everything going in. The ambiguous "Blueprinting", as it were. That will be fine for a young girl to drive (this is a present for my niece). Besides, I have another 1600 long block here if I want to play.

One more question: I'm going to buy a complete engine kit from AA. For literally dollars I can upgrade to a counter-weighted crank. Is it worth it in your opinion? Is it that much smoother?

Get the CW crank. It will keep the engine from slowly killing itself! They all slowly wobble the number 2 main bearing out. CW crank is money well spent, even on a stock engine! Original cranks are forged, so be sure to get a forged CW crank. The cast ones are not very good.

Thu Jul 26, 2018 11:41 pm

VW_Jimbo wrote: Super fun to build your own engine. You will not save any money but will have a blast completing the task!!

The Air-Schooled Math Test:
If you buy something that costs twice as much and lasts four times as long, is it really more expensive?? :lol:

Really though, we're fortunate with Type 1 engines that allow owners to do a VERY thorough job with minimal help from shops aside from advanced machine work. Keep your work space, hands, tools, and parts clean, and you'll be lightyears ahead of some shops already!

This collection of mostly-used parts has already pushed my bus (twice the weight of a bug!) around the country twice, clocking in at 63,000 miles this morning. I didn't do anything special that the factory didn't do, but I did wash my hands about four times an hour, and pay close attention to Tom Wilson's rebuild book.

Multi69s has a GREAT point when he talked about researching the folks who give advice. I stick to the stock VW recipe, so I can use mostly manuals. But when you go down a custom or performance path, you won't be able to mix and match recipes. If you want an engine like Builder Bob but Builder Tim has a few cheaper/different parts, your engine won't be as nice as Builder Bob's. If Builder Jon recommends different cams/heads/valves/pistons, and you try to mix it with others, you'll be your own RnD department, instead of relying on others' experience.

Good luck!
Robbie

Good luck

Fri Jul 27, 2018 1:31 pm

kangaboy wrote: Kerry Chadderton wrote: For literally dollars I can upgrade to a counter-weighted crank. Is it worth it in your opinion? Is it that much smoother?
I think the counter weighted cranks are useful to help get you above 5000rpm. In a stock 1600, with stock heads and valve springs, you don't need it. I would suggest using a balanced german crank, or at the least, ensure the crank that comes in the kit is balanced.

A CW crank is ALWAYS a good addition, even at lower RPMs. However, more important then the CWs is how the crank is made. The stock crank is forged, so its extremely durable. The crank that you are looking at may be cast. Now a "good" cast crank can definitely handle the forces of a stock engine, but you don't know if its good unless you have it magnafluxed.

True story: years back I ordered a cast crank from a company whose name started with Clause. When the box arrived, I heard clanking inside, and my heart sank. Upon opening the box, the crank was in two pieces. At one point, the shipper had probably dropped the package, causing the crank to cleave at a defect point. A forged crank would not have done that. The only way to detect these defects, is to magnaflux it, which adds cost. So personally, if the crank is cast, I would stick with the stock one. My criteria on VW engines isn't based on years, but mileage. If the engine will not last for at least a 100k, either I did something wrong, or I choose the wrong components.

Fri Jul 27, 2018 1:59 pm

Buggeee wrote: I used a set of pistons and cylinders from AA when I rebuilt my 1600 (as a 1600) and a year later it is still running great.

A year later does not mean much. You could have 30, or 300, or 3,000, or 30,000 miles in that time.

To the OP, you should look into the oil filter/pumps that you can buy from CB (the Maxi 2) or the VW of Mexico that was a stock part. Do some reading up in the forums for more info. No modification of the engine case and no hoses to fuss with.

Got to agree about going with a CW crankshaft. The #2 bearing is beat to death due to the poor design of the stock ACVW crankshaft. Added bonus the car will be quieter due to less engine vibration, which in turn creates less having to yell over the engine noise, and less driving fatigue for the occupants.

Got over 150,000 miles since last rebuilt on the 1641 cc (slip in cylinders) engine in our 1960 walk thru panel camper bus. Build it correctly, do not let it over heat (gauges are a must) , and the engine can be reliable with great longevity.