 Type 4 mechanical compression ratio, Why is the factory compression so low? |
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| Beebo Kanelle |
 Feb 11 2016, 01:03 PM
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#1
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Member  Group: Members Posts: 248 Joined: 22-November 12 From: Houston, Texas Member No.: 15,177 Region Association: Southwest Region 
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OK, here's a fun one for the novice to ponder and you experts to answer:
Why is the factory mechanical CR so low? and for reference, what is the highest mechanical CR that can be physically achieved? assume no octane limitations - I'm just looking for the design limit for the highest CR that can be / has been in a Type 4 engine using available technology. Thanks |
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| brant |
Feb 11 2016, 07:39 PM
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#2
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914 Wizard Group: Members Posts: 11,949 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains 
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The materials used in a stock 914 engine do not like high compression.
Water cooling provides more controlled cooling than does steel cylinders on an air cooled motor It's expensive to rebuild with modern components/nickies/etc additionally the metallurgy of the block/heads can play into high theoretical numbers |
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Posts in this topic
Beebo Kanelle Type 4 mechanical compression ratio Feb 11 2016, 01:03 PM
914_teener
OK, here's a fun one for the novice to ponder... Feb 11 2016, 01:27 PM Mark Henry Kind of funny way of asking what is the max HP a T... Feb 11 2016, 02:19 PM colingreene Compression ratio is often set by quality of fuel.... Feb 11 2016, 02:22 PM Dave_Darling Assuming you aren't actually trying to burn an... Feb 11 2016, 04:10 PM r_towle 13:1 at 200 hp
Race fuel only.
Could not move the... Feb 11 2016, 04:14 PM Beebo Kanelle Thank you one and all.
I'm afraid I wasn... Feb 11 2016, 04:35 PM
Steve Pratel
Thank you one and all.
I'm afraid I wasn... Feb 11 2016, 10:11 PM
Mark Henry
I'm sure it can be done, and maybe has, but ... Feb 11 2016, 10:35 PM jd74914
I am modeling the Type 4 based upon other engines... Feb 12 2016, 10:27 AM jmill IMHO twin plugging and race gas are exotic extreme... Feb 11 2016, 07:12 PM ConeDodger
The materials used in a stock 914 engine do not l... Feb 11 2016, 09:06 PM Mark Henry
The materials used in a stock 914 engine do not ... Feb 11 2016, 09:20 PM ConeDodger
[quote name='ConeDodger' post='2301947' date='Feb... Feb 12 2016, 12:17 AM Mueller The cooling, or lack of is why such low compressio... Feb 11 2016, 10:07 PM Beebo Kanelle Thank you all for all your input. I knew that the... Feb 11 2016, 11:04 PM stugray
So to sum up, the enemy that needs to be addresse... Feb 11 2016, 11:53 PM Mark Henry
So to sum up, the enemy that needs to be address... Feb 12 2016, 03:07 AM Steve Pratel Eh, I'm not buying it.
Driveable? Porsche sol... Feb 12 2016, 10:33 AM McMark If you're looking to improve thermodynamic eff... Feb 12 2016, 09:50 AM Mark Henry
If you're looking to improve thermodynamic ef... Feb 12 2016, 10:21 AM jd74914
If you're looking to improve thermodynamic ef... Feb 12 2016, 10:25 AM ra272
If you're looking to improve thermodynamic ef... Feb 15 2016, 03:36 PM Mark Henry
If you're looking to improve thermodynamic e... Feb 15 2016, 03:54 PM Beebo Kanelle guys! I didn't mean to start a firestorm ... Feb 12 2016, 12:12 PM Mark Henry
guys! I didn't mean to start a firestorm... Feb 12 2016, 01:40 PM jd74914
guys! I didn't mean to start a firestorm... Feb 12 2016, 03:50 PM Mueller You really cannot model the Type IV using past mot... Feb 12 2016, 12:16 PM Beebo Kanelle probably not, it may all blow up - but I do want t... Feb 12 2016, 12:24 PM Beebo Kanelle and, if it all blows up, Y'all will be among t... Feb 12 2016, 12:29 PM brant seriously.... as a hypothetical discussion you can... Feb 12 2016, 02:30 PM r_towle I would suggest you call around, talk with JAke Ra... Feb 12 2016, 03:23 PM HAM Inc If your goal is 100hp/liter T4 you're best cha... Feb 12 2016, 04:17 PM veekry9 zcPGfjUO3Yg
https://www.youtube.com/user/Grasshut... Feb 12 2016, 07:19 PM Mark Henry
The 380hp corvair engine, with the coin in it you... Feb 12 2016, 09:32 PM r_towle I admire what you are doing, and that you can do i... Feb 12 2016, 09:39 PM Beebo Kanelle wow! Thanks to all for all the input.
to an... Feb 12 2016, 10:00 PM Mark Henry
wow! Thanks to all for all the input.
to a... Feb 13 2016, 10:56 AM DBCooper
[b]In VW beetles, T4 upright fan conversions the ... Feb 13 2016, 12:20 PM Mark Henry
[quote name='Mark Henry' post='2302557' date='Feb... Feb 13 2016, 12:47 PM r_towle Look at how the 911 turbo seals the head to cylind... Feb 12 2016, 10:18 PM Mark Henry
Look at how the 911 turbo seals the head to cylin... Feb 13 2016, 11:55 AM colingreene Is this thread still going? I lost interest in try... Feb 13 2016, 11:46 AM stugray It might have been lost in the thread:
If you wan... Feb 13 2016, 12:32 PM DBCooper Yup, original OPP with Joe's handwritten instr... Feb 13 2016, 04:08 PM Mark Henry
Yup, original OPP with Joe's handwritten inst... Feb 13 2016, 04:35 PM DBCooper
Yup, original OPP with Joe's handwritten ins... Feb 13 2016, 05:01 PM veekry9 vmkKqVc2g0s
http://www.forestcitycastings.com/serv... Feb 14 2016, 05:14 AM Mueller
Design brief:
1) air/liquid cooled hybrid
2) ... Feb 14 2016, 03:30 PM Mark Henry
Maybe I missed it, but I didn't see him pos... Feb 14 2016, 04:20 PM veekry9 http://www.amazon.ca/Air-Cooled-Motor-Engi...%2C+L... Feb 14 2016, 08:32 AM Mark Henry OK then....enough of the yakety yack...Build it... Feb 14 2016, 09:38 AM veekry9 https://www.google.ca/webhp?sourceid=chrome...mpos... Feb 14 2016, 11:01 AM Beebo Kanelle Thanks Veekry9! Found a 2nd edition (1972) o... Feb 14 2016, 11:14 AM Mark Henry
Thanks Veekry9! Found a 2nd edition (1972) ... Feb 14 2016, 01:01 PM Beebo Kanelle Thank you, Mueller -
I just have some ideas that ... Feb 14 2016, 04:10 PM veekry9 That's the beauty of the freedom of free will,... Feb 15 2016, 12:27 AM Mark Henry
That's the beauty of the freedom of free will... Feb 15 2016, 08:44 AM Beebo Kanelle Its getting done...
maybe not on a Canadian sch... Feb 15 2016, 09:35 AM Steve Pratel :popcorn: Feb 15 2016, 02:53 PM cgnj Please let this thread die Feb 15 2016, 03:20 PM 914_teener
:popcorn:
:bullshit: :idea: :toke: :sleep: Feb 15 2016, 03:21 PM |
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