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  View original topic: Advice on CR, before I order heads
msaltz Sat Aug 11, 2018 6:58 pm

Before I order my heads I want to make sure I am going to be running the proper compression ratio (CR). My initial plan was to run a 9.5:1 CR, but it was mentioned to me that may be to high for the below spec engine? I would like to know what experienced people think and make sure I'm not making any major mistakes. I know this is somewhat subjective but I would like to get some opinions. The engine is going in a 65 ghia that will be somewhat of a daily driver. I have decided on Steve Tim's stage II heads and they can do up to a 60cc chamber.

Engine:

2180cc (92 thick wall pistons/ 82mm crank)

Deck Height- #1=0.0405", #2=0.0435", #3=0.0395", #4=0.0420", These are with a 0.09" shim under the cylinder.

SCAT pro series 1.25:1 rockers;

Dual 44HPMX carbs;

1 5/8" exhaust (I think);

Web 163 cam:
Intake Exhaust
Valve Lash (Inch): .006" .006"
Valve Lift (Inch): 0.430 0.430
Valve Lift (mm): 10.92 10.92
Advertised Duration: 288 288
Duration @ 0.050": 250 250
Lobe Center: 108 108

Not necessarily looking every last drop of HP that I can get with this set up but would like the car to be fun, smooth running and idle well. Any opinions would be greatly appreciated, especially any objections to the 9.5:1 CR!

Thanks,

Cptn. Calzone Sat Aug 11, 2018 9:30 pm

I currently run that cam with Timms stage 1.5 heads.Cool and strong.Make certain of lifter compatability. Comp is 8.5.1 in a 67SC truck.Pulls really well and quiet valve train.Guy that built it did an outstanding job.

74 Thing Sun Aug 12, 2018 12:30 am

I would leave it as it is or change the cam to WebCam 86b with 1.4 CB or Scat rockers.

Tune it good and run good octane gas

https://vwparts.aircooled.net/Web-Cam-Type-1-Camshaft-Grind-163-1-1-or-1-25-p/00-212.htm

Alstrup Sun Aug 12, 2018 1:13 am

msaltz wrote: Before I order my heads I want to make sure I am going to be running the proper compression ratio (CR). My initial plan was to run a 9.5:1 CR, but it was mentioned to me that may be to high for the below spec engine? I would like to know what experienced people think and make sure I'm not making any major mistakes. I know this is somewhat subjective but I would like to get some opinions. The engine is going in a 65 ghia that will be somewhat of a daily driver. I have decided on Steve Tim's stage II heads and they can do up to a 60cc chamber.

Engine:

2180cc (92 thick wall pistons/ 82mm crank)

Deck Height- #1=0.0405", #2=0.0435", #3=0.0395", #4=0.0420", These are with a 0.09" shim under the cylinder.

SCAT pro series 1.25:1 rockers;

Dual 44HPMX carbs;

1 5/8" exhaust (I think);

Web 163 cam:
Intake Exhaust
Valve Lash (Inch): .006" .006"
Valve Lift (Inch): 0.430 0.430
Valve Lift (mm): 10.92 10.92
Advertised Duration: 288 288
Duration @ 0.050": 250 250
Lobe Center: 108 108

Not necessarily looking every last drop of HP that I can get with this set up but would like the car to be fun, smooth running and idle well. Any opinions would be greatly appreciated, especially any objections to the 9.5:1 CR!

Thanks,
9,5 is ok, - on premium fuel. That said I tend to agree on the 86B cam. Then you can go 1 notch down in fuel octane too.
T

mark tucker Sun Aug 12, 2018 10:31 am

ditto,to alstrup, I didnt care for the 163....but it wasent mine somebody else was paying for it so thats what went in.

bugguy1967 Sun Aug 12, 2018 10:49 am

It's looks milder than a W120, and 9.5:1 is generally the limit for that cam. If you do run 9.5, you need to be pretty knowledgable about AFR and ignition timing. 9.0:1 is safer.

The Stage 2s are kind of big for your cam. They flow about 180 CFM@25"/.550". You'd be better off with the Stage 1s. Or even better, CNC chamber Panchitos.

msaltz Sun Aug 12, 2018 3:38 pm

Thanks for all the input. I am leaning towards going with the Tim's Stage II heads w/60 cc chambers. With my not very consistent deck heights that should put me about 9.1-9.2:1 CR. I'll role with that and see how it performs.


Thanks again.

mcmscott Sun Aug 12, 2018 6:05 pm

msaltz wrote: Before I order my heads I want to make sure I am going to be running the proper compression ratio (CR). My initial plan was to run a 9.5:1 CR, but it was mentioned to me that may be to high for the below spec engine? I would like to know what experienced people think and make sure I'm not making any major mistakes. I know this is somewhat subjective but I would like to get some opinions. The engine is going in a 65 ghia that will be somewhat of a daily driver. I have decided on Steve Tim's stage II heads and they can do up to a 60cc chamber.

Engine:

2180cc (92 thick wall pistons/ 82mm crank)

Deck Height- #1=0.0405", #2=0.0435", #3=0.0395", #4=0.0420", These are with a 0.09" shim under the cylinder.

SCAT pro series 1.25:1 rockers;

Dual 44HPMX carbs;

1 5/8" exhaust (I think);

Web 163 cam:
Intake Exhaust
Valve Lash (Inch): .006" .006"
Valve Lift (Inch): 0.430 0.430
Valve Lift (mm): 10.92 10.92
Advertised Duration: 288 288
Duration @ 0.050": 250 250
Lobe Center: 108 108

Not necessarily looking every last drop of HP that I can get with this set up but would like the car to be fun, smooth running and idle well. Any opinions would be greatly appreciated, especially any objections to the 9.5:1 CR!

Thanks,



Your deck is all over the place! fix that first! then ask questions

mark tucker Mon Aug 13, 2018 10:36 am

I figuyred he wasent all that carfull checking the deck hight....or in the right /same position on each setup...I would also suggest the lost pan of cheetos cb heads for this build.CNC of course.

74 Thing Mon Aug 13, 2018 8:57 pm

Why don't you ask Tims what to run and have him set up the heads for the compression you want? They know their stuff.



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