Is 8.6:1 too low for a W120?

[Sigurd]

Just a quick issue I'd like to get some confirmation on. I have L5 heads with 55cc chambers. If I set the deck to 0.045" without touching the heads, how's my CR sound?

[gerg]

Need to know bore and stroke . . .
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Gerg

. . . I got 99 problems and my bus ain't one . . .

'65 Sunroof Beetle
'65 Vert
'60 Singlecab

[dubkrzy]

Like Gerg said, but no, 8.6:1 is not too low for a w120
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[Sigurd]

Duh, sorry. 1915...69 x 94.

[gerg]

8.6 sounds nice and cool especially if it is in a bus.

What is it going in?
_________________
Gerg

. . . I got 99 problems and my bus ain't one . . .

'65 Sunroof Beetle
'65 Vert
'60 Singlecab

[Sigurd]

It's going in my '66 Bug. Can I close the deck down to 0.040" with Mahles and Unitech rods? That would be 8.7:1.

[madmike]

I have a cpl engines with that cam and the higher the cr the better they run,I'm thinking there O'school when the Gas was a better grade??? My 2332 is around 10.5 to 1 or 11:1 I cant' remember Runs way better on Race fuel,and the 1915 is about 8.5 to 1 just not as snappy as i wanted so I'm tairing it down someday,madmike
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'Black Ice'Drag Buggy 'Turbo'
Rail Buggy 1915 turbo
76 Drag/Street bug 2180cc 'Turbo' 11:85 @113 mph"If I go any faster I'll burn up the Hamster" ,gets 28 mpg. also 10/09/22 11.90 @115 mph
"If I'm ever on Life Support,UNPLUG Me, Then Plug me back In see if that Works"

[joescoolcustoms]

[Sigurd]

Ok, well maybe I'll keep it at 0.050" then and get the heads cut a bit. Darn. I was hoping for 9:1.

[cal63look]

I run the Engle 120 and my CR is at 8.9 with a deck of .040, also engine is turbo charged.

[Sigurd]

Thanks for the comments guys. Maybe a better question to ask is, is the power vs. heat difference between 8.5 and 9 worth it? Or does that cam just need more? This is for a street car that sees weekend use and won't be raced.

[cal63look]

With a higher CR motor you will need to run premium fuel. I do not have any heat issues with my CR and turbo setup (and the motor is fully chromed out). I run an oil pressure gauge, oil temp gauge, tach, electronic fuel pressure gauge and boost gauge. Of course you wouldnt need the last two But I have driven my car daily and as a weekend warrior with no issues of heat. I have never checked the head temps but the car runs great (and no signs of extreme head temps). The cam will use the CR properly because you'll be running it in its intended range of CR. Before my motor was turbo'd I ran a 2020cc and the CR was at 9.1, no issues of heat with that setup either. Car was well mannered and was a Daily driver with that setting also. I have driven my bug from drag strip to home, aswell as driven it to vw shows that are about 100miles away from my city (one way). Also driven it to different mountain areas here in colorado.

My car will idle great at about 800-900 rpms. Very well mannered. I still find it funny that some people will run such low CR's with turbo setups, but that a whole other story of Boost versus CR (dont really apply to your question)

Just make sure you have a doghouse oil/fan setup, fan belt is properly tightened (run all the proper cooling tin, dont use a power pulley), full flow your motor, and run a deep sump. Also you'll want to also tweek your timing for the increase in CR.

[cal63look]

Also i forgot to add, you'll have to run the numbers and measure everything for deck height and the cc's of your heads (which is sounds like you have). You dont want to try and acheive a high'er CR with a super tight deck height, then you may be asking for trouble. Oh and as a side note I run 1.25 ratio rockers with the W120 along with the deck of .040 which further increases my lift. Also you need to run chromoly pushrods with those dual valve springs that are hopefully in your heads. Set the lash on those to a loose zero, where you can just spin them with your finger. The motor will expand around those to achieve the lash you need.

You may already know this stuff, but just throwing things out here as I think of them.

[Sigurd]

I am running oil temp., oil pressure, and a compensated head temp. gauge. The engine is full-flowed and will use full tin and thermostat, all of which I have in boxes waiting for me. I have a sump, but am thinking of not using it because I am lowered and this isn't a race engine. Still on the fence about it though. Pushrods are chromoly and rockers are 1.25.

I hae checked everything, and the parts are fine, except for the case. Current values are 0.058", 0.054", 0.060", 0.052". I did measure the cc, deck, piston height, rod length, cylinder length, all that. I can't even switch pistons and rods because they are all dead nuts on! The head ccs are 53/53 in one head and 54.2/53 in the other. All said, each cylinder is only 0.1 difference, 8.4, 8.5, 8.6, 8.7. But I can't have uneven cylinders because the heads won't seal.