Stroker project

Michael- Just looked in the Berg catalog, and it's -8. They've used that size for oil hose as long as I can remember.

Al, thanks for checking.

 

I don't know how good your memory is. I bought my engine parts in 1983. Just measured the hose and it is -6.

 

Is it OK to leave it at -6?

 

If I should change it to -8 is there a way to connect an -8 hose to the fittings on the case? Is that a reasonable thing to do?

 

If I change the filter lines to -8 do I need to change the Accusump line too?

 

 

If you've got -6 fittings on the case, attaching a -8 hose to it isn't going to benefit much as the smallest diameter cross section in the entire path is what ultimately limits the flow. You'd want to change everything to -8 if you were going to do it.

 

The stock oil pump outlet into the case is around 1/2" in diameter (-8). So it makes sense to keep the external oil filters, coolers, and hoses the same -8 size to avoid restrictions.

I am getting in this at the tail end of everyone's input. 

First you should use #8 lines for the oil at a miminun. 

#10 for breather lines is preferred or #8.

i do not see the need to add a accsump unless your vintage racing the car.

I like to set up the electric fans with a manual switch. 

If your running a porsche design shroud I run one oil cooler from the filter line back to the motor and the second cooler from the stock oil cooler location. Much more efficient . Than in a series.

to run all this oil the case must have a decent pump, case full flowed, and a large sump.

the initial cost may be high but in the long run using AN fittings is much better. Less chance for leaks, and you can make a bypass hose if for some reason the cooler leaks while on the road.

thanks for letting me give my two sense.

I already have the Accusump. Gene Berg told me I could use that instead of the added sump.

 

I plan to use AN fittings. I am undecided between stainless hose or push-loc/twist-loc.

 

I plan to upgrade to -8 hose from the current -6 even though -6 matches the 3/8 pipe thread fittings at the pump and case.

 

I looked at several pump covers today and they all seem to use 3/8" pipe thread fittings. So, that would be the smallest thing in the path whether -6 or -8 hose is used.

 

I thank you for your contribution.

I ordered the oil cooler today. The cheapest place I found is Kartek.com.

A 3/8 NPT fitting's inside diameter is equivalent to -8 AN, not -6. If you ever look at a 3/8 NPT to -8 AN adapter union it's basically straight through with no size difference. If that's what you've got on the case, you won't have any problems going to -8 fittings and hose.

Please don't think I'm talking down to anyone, as that's not my intent.  Many of you likely know the following already.  

 

Some basic hydraulics: the reason we want larger hose/pipes when moving fluid is that the movement of fluids takes energy, usually described as friction loss.  Basically, the slower a liquid can move, the less energy it takes to move it.

 

This means that a larger hose allows fluid to move slower, thus not taking as much energy to do the job.  Less friction loss = more fluid moving.  There are lots of standard friction loss tables that tell hydraulic engineers the optimum size for hoses/pipes, depending on flow, usage, type of liquid, temp, viscosity, etc., but the same pump at the same rpm is capable of moving more fluid through a larger orifice than a smaller one.  Friction loss is the main reason why that occurs.

I was comparing the 3/8 NPT i.d. (which I assumed would be close to 3/8" with what I assumed was the hose i.d.

 

I can see that the AN adapter i.d. would be close to the 3/8 NPT fitting i.d.

 

In any case, I do plan to go with 8AN. I will have to replace a bunch of nice hoses.

 

Thanks.

It seems like the friction at the pump and case would be about the same for a 3/8 NPT to 6AN adapter and a 3/8 NPT to 8AN adapter.

 

But, I can see that the -8 hose would have less friction than the -6.

Very well said.




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So, if I run the pushloc hose, I'll be okay?

 

No sense in over thinking this unless I'm under thinking it.

Ted

Ted,

 

I use them on breathers, but not pressure hoses. Call me a worrier, but I think I'm just being careful.

Quick disconnect fittings (Parker et al) have numerous configurations, which run the gamut from minor to major constriction, due to narrowing the fluid passage diameter.  A straight disconnect with no internal valves offers the least restrictive configuration, as opposed to fittings with check or one-way valves, restrictors, etc.  Take a look at the two pieces of the fitting when apart.  The male end of a 1/2" quick connect fitting can be as small as 1/4", or even less, depending on manufacturer, type, etc.

 

Not sure why you would need a quick disconnect, though.  Possibly it's difficult to get a wrench on the fitting.  However, if you only need to open the fitting twice/year or so, a manual version may be preferable.  You may be able to move the manual fitting to a more accessible place in the system or hose length.  As Stan suggests, there is a safety factor also.  The concern is not really the fitting, as the fittings of major manufacturers are dead reliable, if properly connected.  It's the cockpit problem, thinking you connected the fitting properly, but didn't.  

Yes, push-loc hose and push-loc fittings, you'll be perfectly fine.

I have used the pushloc for fuel lines and on scavenge lines for oil, but either a crimped or AN fitting on a pressure hose. There are some decent push loc fitting but you have to use a really good design hose for pushloc fittings. Most speed shops don't know which products work the best together. they just sell it because its the product line they carry. Try to fine a shop that specializes in hoses and fittings. May cost more but your better off in the long run

If your swapping motors daily I may consider the dry break or quickrelease fittings. I used them for brake lines so swapping out the frt or rear axle on the race car and disconnecting the brakes we would not have to bleed them. Other than that there is no need to waste your money on them

I've had pushloc fittings for 8 years now with no problems.

Berg also uses the Teflon braided hose which also less restrictive than a rubber core hose. The teflon hose is also three times the cost of the rubber based hose and the fitting are also.

I sort of caught up on this subject. Been on the road to Texas. In Texas now.

I have always liked those 42 DCNF carbs you have and think you should re-use them again on your 2110. Re-jetted of course. I'm using a set of 44s now but replaced the 36 mm venturi's and replaced them with 32's. The drivability improved and I have absolutely no acceleration    lag,bog or hesitation. I gave up approx. 3 HP on the top end according to the resident expert at CB Performance.

You probably have 34 mm vents in your DCNF's and my guess is that they will perform just      fine on your 2110. I also think that the idle jets are a little less susceptible to getting plugged up with debris. The Weber 44's  look really cool but those DCNF's work pretty darned good.

That's now 4 cents from me. Whatever you do you will really like the output of your 2110 !

The dcnf' are great carbs for a vw. Just not many people have the mindset to tune them. The idf work fine for the average setup. 

Michael, I used AN-8 fittings throughout on my remote full flow setup. But instead of steel braided hose I bought the nylon braided hose. MUCH easier to work with. Plus, I ran it down my powder-coated frame and didn't want to deal with abrasion from the stainless hose. A bit cheaper too. All in all, a win.

 

If you were going to pipe the cooler to the front then use AN-10, but if it's all in the back AN-8 are fine.

 

As an aside, I bought Gates pushloc hose and fittings initially. The hose blew off the oil filter fitting on initial startup at around 2000 rpm. I had to clamp them to make them stay on. Immediate shutdown so motor was fine. Left them on with clamps for a few years but now I have AN.

Danny, I plan to use AN-8 TPFE (Teflon) hose from anfittingsdirect.com.

 

They have a good range of hose sizes and their price for hose and fittings is about half of other sources I checked. I realize it is probably made in China. I have read that it is the same source as Jegs and Summit house brands.

 

Here is a good video about how to assemble the hose ends:

 

https://www.youtube.com/watch?v=WMlRXzQ0s9U 

For a given compression ratio we could have a smaller combustion chamber in the heads and a bigger deck height or a bigger combustion chamber and smaller deck height.

       
       

For the most efficient burn you want zero deck. Cut valve reliefs in the pistons. You want the combustion in the chamber not the cylinder barrel

Anthony is right, you want as little deck as possible so the burn doesn't transfer heat to the quench pads of the piston and head.It's generally accepted that .040" deck is pretty well the minimum in a street engine, and .040-.050" is what most people shoot for; any closer and losing a rod bearing and the piston can hit the head (not that you don't have enough problems already, with the engine knocking like crazy). You can fudge that by a couple thou, but I wouldn't go too far. As Anthony said, you'll need to make sure there's adequate piston/valve clearance if you have a lot of lift. As well as tranfering more heat to the piston and head (and the cooling system having to get rid of that heat instead of it going out the exhaust), some people say too much deck can make an engine run somewhat sluggish and be harder to tune.

 

PS- More later if it doesn't get covered...Al 

My builder suggested 52cc combustion chambers, 9.1 compression and .08 deck.

 

I thought I might want less deck and more than 52cc.

 

He has built a lot of engines over more than 30 years. I hate to keep questioning his suggestions.

 

The thing I see here is the builder taking the easy way out; yeah he's built a ton of engines, probably a fair number with lots of deck, and it works, but how well? I know he'll say he's got no come backs, and his customers will say they run fine, but compared to what? I'm sure they've got more power than they thought possible, but they have nothing to compare it to, and it you were to look closely at how they run you might find they were a little shortchanged. Just so you know, production engines today are built with minimum deck; the engine is more efficient, makes the best all around power, is easiest to tune and is the most trouble free. Minimum deck is proven technology.

 

I take it this is a 2110 (82x90.5)? Have you bought the heads? Did you end up ordering from Aircooled.net? If you did and the heads haven't come in yet, call him to see if the the combustion chambers can be enlarged. As I said before, .080" deck will run, but it's not optimal. Remember, you're the one footing the bill here, and there's no reason he shouldn't do it the way you want.

 

I know I'm kind of a dog with a bone on this, but I think it's important.

I suggest if you like the guys work then go with it. It's great to have this forum to bounce ideas and get others feedback but you should take the info and ask your builder what he thinks or has he done or tried this before? Make it like your trying to learn from his feedback and not the forums. .008 is finesse long as the valve has clearance and he allowing for growth. Some builders use the copper gaskets between the head and barrel. Be sure he meant eight thousandths and not 80.

I went back and checked your post. .080 is a lot.  It will run but not as efficient as terry or Mitch motors. Email me if you want to discuss it further

The chambers of the heads start at 60cc.

 

Thursday I told aircooled to make them 52cc based on what the builder said.

 

I don't know if it is too late to change now.

 

Although I'm the one footing the bill, sometimes I think if I want him to stand behind the result I should follow his advice.

 

 

The thing I don't get, Michael, is if your guy has the opportunity to build it with bigger combustion chambers and a closer deck with heads that have larger combustion chambers to begin with, why would he choose to to flycut the heads to a much smaller combustion chamber size and run a larger deck? It goes against everything we know about current engine burn technology and efficiency. And I know, you'll talk to the guy and he'll say " I've been doing it this way and never had a problem" or something similar, but that doesn't mean it's right. Lots of older mechanics are set in their ways (and let's face it, a lot of VW mechanics are retirement age or older, just like a lot of us), and could learn a thing or 2 if you could get them to stop being so eff'n stubborn. Engine science is a dynamic field- the industry is learning new things constantly and and applying them to new cars every year, and that's why automotive technology is constantly evolving, and this is 1 thing we know works.

 

What about proposing an "experiment" to your mechanic- try it your way and see what happens. Call first thing in the morning and see if they can cancel the flycut- 60cc chambers with .040" deck equals 8.9:1, which is close enough. You'll save money on the extra machining charge (not that it really matters) and the thing will run better. Or cut them down to 58cc's, set deck height to .045" and compression will be 9.1- just a little more all around power (although to be truthful, you probably won't feel the difference). And just maybe you'll teach an old dog a new trick...

 

PS- Taking that 1mm (per side) out will make the engine sheetmetal that little bit easier to fit properly and the pushrods will be a teeny bit lighter as well; nothing huge, but all plusses... 

I agree too that 0.080 deck is too much. The more efficient burn with 0.040 is going to let you run a bit more timing too. It would take a 0.1 inch longer rod + 0.060 barrel spacers or trimming the barrels 0.040 to do it.

0.040 deck with 52cc chambers will put you at 10:1 which would require a bigger cam, moving the power band higher and a less friendly idle.

Justin, are you saying to get .040 I will need the longer rods and 0.060 barrel spacers?

 

I do have 5.5" rods.

Michael- There are so many variables- has the case been decked? rod length? cylinder length? piston pin height? that it's best to mock up the the engine with pistons and cylinders, and measure deck height on each. If there's not enough deck- shims under the barrels and if there's too much then having the barrels machined to proper height is how it's done. Work with what you have (don't be buying new rods); this is the easiest and most accepted way to adjust deck height. Whether using shims or machining cylinders, remember it has to be the same on each side so the heads sit flat on the cylinders.

 

Did you enquire this morning about your heads?

My old rods were stock VW rods for 69mm stroke.

 

I ordered new B pistons and cylinders and rods for 82mm stroke.

 

I did not yet inquire about the heads. 

I just got this email from the builder "Michael. , I think you should have one of your internet experts assemble your motor , thanks anyway"

Actually, going back and doing the math, you may just need to change the barrel shims to do it. Assuming your case isn't decked, barrel lengths are stock:

 

Case centerline to stock case deck: 100mm

Barrel length (stock): 112.5mm

Barrel length (94mm dia): 114mm

Half stroke: 82mm / 2 = 41mm

Rod length: 139.7mm (5.5in)

Piston face to piston pin ("A" height pin - stock): 39.6mm

Piston face to piston pin ("B" height pin 90.5/92mm dia): 34mm

Piston face to piston pin ("B" height pin 94mm dia): 35mm

Piston face to piston pin ("C" height pin): 26.8mm

 

Top of barrel: 100 + 112.5 = 212.5mm

Top of piston: 41 + 139.7 + 34 = 214.7mm

Deck height: 212.5 - 214.7 = -2.2mm (your piston sticks out the top of the barrel 2.2mm)

 

To get a +0.080" (2.03mm) deck, I'm guessing you're probably using 4.23mm (0.160") barrel spacers. To get +0.040" deck, you'd change to 0.125" spacers.

 

Of course this is all just math based on the specs, everything must be actually measured to get everything right. And I guessing on some of the parts you're using.

 

Where things get off from the "easy 2110 combo" is the use of the 5.5" rod. The "B" piston was originally designed for 82mm stroke and 5.4" rod length as that gives a nominal piston top height of 212.16mm for basically a near zero deck (+0.013") combo. Slap a 0.040" barrel spacer or copper head gasket on there and you're done.

 

Point is there's many ways to set the deck height: rod length, piston height, barrel shims, decking the case, and trimming the barrel length. Decking the case and trimming the barrels are really last choices, especially the barrels as it just makes replacing them harder in the future.

Seems like your mechanic was intent on building what he wanted to build and not what you wanted to build (and pay for)! 

 

 

 

 

A good builder would be able to convince you why his approach was the right one rather than throwing a fit.