MS3v3 System for CNP and EFI/Turbo "Beetle"

[kangaboy]

Hey all, just wanted to throw an update on my build page. Just been putting around here and there when the weather warms up and is dry enough. I have a nice conservative fuel and spark map in right now, and haven’t really touched it, because I haven’t had more than a day at a time to drive it. I also put some new seats in the bug from a Celica GT. They are such a nice improvement when winding around the back roads. Having some lumbar support and the bolsters are a real treat compared to the stock beetle seats. Took out all of the old mounts and welded in a few new ones for the Toyota seats.
I have been pondering motor upgrades a lot lately, and have come up with a couple trains of thought. They obviously both include more boost...because having a turbo car run on 8psi and stop revving at 5k is a brutal way to live. It’s only been a few months and I need more One idea is; I want to build a bigger motor so I can really utilize the full potential of my set up and get some serious boost going. I was thinking 2180 (82x94). But at the same time, i only have a few thousand miles on the motor that i just rebuild 5 years ago. My second thought is: just put in a new counterweighted crank, maybe with a little more stroke, and upgrade the valve train with a new cam, and call it a day. Maybe just a 1904cc or a 1956cc, that way I could just keep the same P&Cs, keep the same stock heads and maybe even the same rods. I think the latter is a much more acceptable and realistic idea, so I will likely go that route.
So if that’s the case, I was shopping around on CBs website and they have counterweighted 74mm or 76mm cranks for $200. I realize this may muck up all my compression and geometry, but I can work that out as we go.
As far as a cam, I have no earthy idea what would work well. I have the weber C25 right now, which is pretty equivalent to the Engle 110. I guess i need to do a little research and figure that out.
Any thoughts or suggestions on my idea? Would love to have a small stroker if possible. I only have a few months before spring now too. So I may just be planning this stuff for next year.

[SC3283]

74mm will be minimal case clearancing. DPR is tough to beat for cranks, IMO

[ps2375]

I don't understand how you are planning on changing stroke and keeping same pistons, unless you are changing the rods.

[Piledriver]

The spacers to go 74mm are still ~acceptable, although I'd probably lean more towards a welded 69mm German CW crank from DPR and boost it a little harder, add dual springs. KISS. Forged pistons probably a good idea if they exist.

[ps2375]

Oh yah, forgot about spacers... But, as Pile said, if you plan on turning up the boost, a forged piston will be almost required to keep things whole and not hole....

[kangaboy]

The only reason I was going to increase the stroke was because I'm going to swap cranks. I just thought that if I was going to put in a C/W crank, I could put a little extra stroke on it. The forged C/W 69mm that Pile speaks of sounds pretty tempting though. No change to anything, just a quick crank swap and some better springs.

[Clonebug]

Just crank the boost and rev it higher.

I used to hold my engine to 5000 but got a slight amount of lag with the new turbo.
Revving to 5200 rpm fixed that. Now there is no more lag.

What I found in the 5 years I have run a turbo is that rpm is the easiest way to get hp.
I have gone as high as 5800 rpm and the power gain is substantial.
On a street engine you won't be revving it high very long so hold the throttle pedal down a little longer and let it rev.
Once you crank the boost you will want more....But get ready for constant upgrades to continue the addiction.......

There are guys in Sweden and Norway that have been revving stock cranked 1641 cc engines to 7000 plus rpm and they live long lives. They are also boosting to 30 plus lbs.

YMMV.

[Piledriver]

The stock crank i fine if well balanced up to about 5000, and over ~6000.
Unfortunately if it spends any significant time between 5 and 6K it will destroy the case quickly, as it has a nasty resonance that makes it whip around like a very heavy noodle.

The added mass of the counterweights gets rid of that resonance, VW did it another way on the WBX cranks, simply making the webs larger. Also a solved problem on T4s ~the same way, also with larger mains.

[kangaboy]

Unfortunately if it spends any significant time between 5 and 6K it will destroy the case quickly, as it has a nasty resonance that makes it whip around like a very heavy noodle.

What is the definition of significant here? Like 3-4 seconds while I shift through 1st 2nd and 3rd gears? Or are you talking like cruising for miles at a time?
I'm weary of doing this either way, as I never had my crank and rods balanced...
I feel at the least, I would have to tear down the motor to deal with that issue, and may as well throw in another balanced CW crank while I'm at it.
And I was under the impression that revving stock valve springs past ~4800RPM would cause valve float. Yet again, another upgrade. Albeit, one that I was planning on doing in the first place.

[Piledriver]

Given what cases cost, and what a counterweighted crank costs, it's really not worth keeping the "stock" non-counterweighted crank except for bragging rights.

The case center main will simply accumulate damage at a faster or slower rate depending on usage.
They eventually beat out even if driven by grandma.
A well balanced CW crank can essentially prevent the case damage, or at least slow it down tremendously.

[kangaboy]

We have had some spectacular weather here in the Midwest, so I have been trying to put some miles on the bug. Drove it to work Friday with no issues, until trying to leave happy hour that night. Electrical gremlin. I always turn the key to "on" to let the fuel pump prime for a few seconds, and then try to fire it up. Well I let the pump prime as usual, but then when I went to turn it over everything went dark. Thinking it was just a hiccup, I turned the key off and then tried to fire it again, and this time it fired up. Then, I went to turn the lights on...and there was a large stutter, like everything lost power again, but only for a second. I tried to rev it up a few times to get the alternator going, but it never seemed to get up to the typical 13.5-14 volts it usually does. Anyway, I made it home. Next morning got up to go take care of a few errands. Tried to fire it up and got nothing. The radio, alt, and oil lights came on, and the volt gauge was about 12.5, but when I tried to turn it over, there was nothing. And after the initial turn over attempt, the volt meter wouldn't even budge, and the oil light was super dim. Put the battery charger on it for a few hours, and tried to turn it over again...one large click or pop, and then it was back to dead again. Opened everything up, and all fuses and wires looked good. Nothing really jumped out at me. The battery isn't even 2 years old yet, and the bug is always stored in the garage, so I would suspect it to be fine, but idk. This isn't what I was looking forward to with all this nice weather we are supposed to be having.

[Clonebug]

Try cleaning your battery posts.

I had a problem with my positive cable that after 11 years on the buggy the connection just wouldn't hold anymore.
Even after cleaning it seemed there was low voltage.
I bought a new cable, shined up the clamp a bit and installed it....that was the end of my voltage problems.

[Piledriver]

I'm with clone, lead (as used in battery terminals) oxidises. Doesn't matter if it is parked in a garage.

[Chip Birks]

I literally went through this this last weekend. My car has had the same no start/crank symptom for a month or so now. Finally had decent enough weather to get the car off the ground and yank the starter. I ended up testing the starter, and it tested fine. So i pulled the cable and replaced that. The car fired right up and is good to go. Easy fix! Just annoying.

[kangaboy]

You guys rock! Next round on me
Took both leads off, cleaned them up, and cinched them down good. Cranked right over like there was never an issue. Weather looks like it will be nice enough this week to get a few round trips into work.