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Otto-10 diffrences
Posted by: jfreez ()
Date: September 14, 2022 11:07AM

on clarks under the otto-10 cam shafts, there is are two numbers, one for turbo and one for non turbo.

what is the difference?

I have a new OT-10 that I want to use in my 65 turbo, will it work?

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Re: Otto-10 diffrences
Posted by: scottymac ()
Date: September 14, 2022 12:32PM

jfreez: Can't provide the answer you want, someone more knowledgeable than me will step in, but thought I'd offer this page from 1977 OTTO PARTS catalog. Appears at that time, O.P. offered proprietary camshafts just for turbo engines, so not sure how cams for naturally aspirated engines (your OT-10) would work for you.

Scott
Danville, In.
'65 Corsa coupe basket case
'66 Monza coupe


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Re: Otto-10 diffrences
Posted by: jfreez ()
Date: September 14, 2022 01:11PM

Thanks for the info. I am a bit clueless on cams, I just wound up with a bunch of great new parts and want to use as many as possible to save money on my build

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Re: Otto-10 diffrences
Posted by: jfreez ()
Date: September 14, 2022 01:31PM

I found some data sheets for each. I will have to talk to my builder and see how much difference it will make.
Cam specs



the parts I am planning to use for my 65 turbo are stock crank, stock 180 heads, large bore full fin cylinders with ross forged pistons.

If the OT-10 will be good for street and at least get me stock performance, then I will use it. if it hurts me because of the big bore, then I will need to look for something else

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Re: Otto-10 diffrences
Posted by: Wagon Master ()
Date: September 14, 2022 01:42PM

Are you asking what the differences there are in these cams, or the difference these specs make in a turbo engines performance?

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Re: Otto-10 diffrences
Posted by: jfreez ()
Date: September 14, 2022 01:46PM

Wagon Master Wrote:
-------------------------------------------------------
> Are you asking what the differences there are in these cams, or the difference these specs make in a turbo engines performance?


The difference these specs make in a turbo engine performance.

basically if I spend the money for a TB-10 will there be any noticeable difference?

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Re: Otto-10 diffrences
Posted by: dryenko ()
Date: September 14, 2022 01:48PM

In general, a Turbo cam will have less exhaust duration, because the turbo is pushing air and fuel mixture.into the combustion chamber.
At a pressure twice atmospheric of more.
This means less of the un-burned mixture gets push out the exhaust tract.

Bob C aka Dryenko
Dobson, NC 27017

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Re: Otto-10 diffrences
Posted by: 63turbo ()
Date: September 14, 2022 05:48PM

dryenko Wrote:
-------------------------------------------------------
> In general, a Turbo cam will have less exhaust duration, because the turbo is pushing air and fuel mixture.into the combustion chamber.
> At a pressure twice atmospheric of more.
> This means less of the un-burned mixture gets push out the exhaust tract.

smileys with beersmileys with beer

Will the OT-10 work on your turbo??? Heck yes it will! Honestly I think it will work a hair nicer than the TB-10. I ran one of those and while I was happy with it, one thing I didnt like was how much more ping sensitive it seemed to be, and was probably caused by shutting the exhaust a little sooner. Remember, the early Turbo's did run the same cam as the hotter NA engines.

------------------------------------

Kevin Nash
Friday Harbor Washington
63 Spyder, Daily driver, EFI read about my project here: [corvaircenter.com]
first test start on EFI here:[www.youtube.com]
first official EFI boost test here:[www.youtube.com]
My new fan! [corvaircenter.com]
engine less 62 Spyder
Canadian 64 Monza Parts car
Test Start#2 [www.youtube.com]



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Re: Otto-10 diffrences
Posted by: v8vair ()
Date: September 14, 2022 06:46PM

Basically it’s all about cylinder pressure, how much you can stand before detonating, less overlap creates more pressure under mild boost ( street motor )
Big Boost , tight lobe centers , lots of overlap bleeds boost off through the exhaust ( race motor )
The more control you have over timing, jetting, intake temps , etc the more power you can make. Simple but complicated smiling smiley

1964 Bill Thomas Monza Replica Racer
1964 Spyder Street Car
1998 Honda Prelude Dirt track car
1967 Crown V8 under construction
Mike Levine

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Re: Otto-10 diffrences
Posted by: wittsend ()
Date: September 14, 2022 07:39PM

"...less overlap creates more pressure under mild boost ( street motor )
Big Boost , tight lobe centers , lots of overlap bleeds boost off through the exhaust..."


Very well stated and why it is important to understand the differences between Static and Dynamic Compression Ratios.

------------------------------------------------------------------------------

***'61 Lakewood, a "Freebie" in hibernation for 27 years - In the process of applying CPR.***

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Re: Otto-10 diffrences
Posted by: 67vair ()
Date: September 15, 2022 06:55AM

I have used the OT-10 in both a 140 and turbo and I thought it was a great cam. Very smooth and tractable on the bottom end with a strong mid-range, starts to flatten out a little above 5K but that's OK for a street motor. I think you will be happy with this cam.

69 Monza, owned since 1975 daily driver
67 Monza, owned since 1981, being restored

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Re: Otto-10 diffrences
Posted by: jfreez ()
Date: September 15, 2022 08:22AM

Sounds like I am going to save a few bucks with this cam. It already has a new cam gear on it (I think its a failsafe). I should be able to have this engine together sooner than I thought.

Thanks to everyone for your help

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Re: Otto-10 diffrences
Posted by: Wagon Master ()
Date: September 15, 2022 08:48AM

Should work out fine(ish). As 67vair said, you should have great low end. When it starts to flatten out around 5k, you should be right in the middle of the boost sweet spot

Been aircooled since 1973
Northwest Ohio 45840

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