Click the link below to download the Compression Ratio Calculator spreadsheet. drive.google.c... Please Like, Share, Subscribe, and Ring the Bell for notifications!
I'm honing lifter bores now (broke the hone and had to order another). I plan to final wash and start assembly this weekend. It will be a slow assembly as I am blueprinting everything. Hopefully I will have it running in 30 days or so. I also have to build a run stand. I have the plans and the materials for the run stand, I just need to get to it. Everything takes soo much longer than it used to. Getting old stinks.....
3/3/2020 I fixed and error in the spreadsheet. Volumetric Efficiency is not calculated. It is entered. I had it locked in as .85. Typical values would be from .80 to 1.0.
Hi, I stole a spread sheet and changed it a bit, doing a 350 build and researching my max compression ratio with trouble, I have found that its more importan to get your DCR correct before you SRC,for some reason my links in comments are not showing so will try post below, please try it and see what you think, Brett
UA-cam flagged your links a "possible spam" and left them for me to review. I approved them so they should show up now.When I created my spreadsheet, this was all new territory for me. I did it to help me get my head wrapped around it. I downloaded yours and look forward to playing with it after reading the info you linked to. It will probably be a few days before I get a chance to dive in between my work going crazy and running to doctor appointments, I don't get much else done. I really thought this would be a more popular subject but I don't think very many people are willing to put in the effort to try and understand the subject. Thanks for your info and commenting.
@2Old2Rodeo Great thanks.....lucky you have work we are still in lockdown in NZ up to our 4th week at home,hope you are well, yes there seems to be not much info out there, the biggest problem I have is if you are arming for a DCR of 8.3:1 the SCR is not that high say around 9.2:1 which does not sound like a high compression engine to me, I have a couple of good books and they both say stay around the 9:1 using your Premium 91AKI (our 96 Mon) with Iron heads and 9.5:1 with Alloy heads, there are people on youtube claiming upto 13:1 with alloy heads on pump gas, there ignition must be retarded to compensator or they did the calculations wrong, here is another little program to double check your figures download it from his web site and try it, ua-cam.com/video/vgclz3FOq_Q/v-deo.html Cheers Brett
@@kermets I am at 11.1 to 1 with cast iron heads. I decided to go with E85 for fuel. I have about 2 hours run time on the run stand and everything looks and sounds good. I have to tie up a few loose ends and then I hope to get it on an engine dyno to test and tune. I will get back to you once I have a chance to digest your info.
When do you think you will have it built?
I'm honing lifter bores now (broke the hone and had to order another). I plan to final wash and start assembly this weekend. It will be a slow assembly as I am blueprinting everything. Hopefully I will have it running in 30 days or so. I also have to build a run stand. I have the plans and the materials for the run stand, I just need to get to it. Everything takes soo much longer than it used to. Getting old stinks.....
That's awesome great work
Thanks!
Watch Eric the car guy on UA-cam he just built a similar setup with aluminum heads and it broke 6 pistons from detonation on premium 93 octane
Thanks!
3/3/2020 I fixed and error in the spreadsheet. Volumetric Efficiency is not calculated. It is entered. I had it locked in as .85. Typical values would be from .80 to 1.0.
Debug
Hi, I stole a spread sheet and changed it a bit, doing a 350 build and researching my max compression ratio with trouble, I have found that its more importan to get your DCR correct before you SRC,for some reason my links in comments are not showing so will try post below, please try it and see what you think, Brett
bit.ly/3hgRMlo
my spread sheet
bit.ly/3z7RbJf
here is some DCR info
UA-cam flagged your links a "possible spam" and left them for me to review. I approved them so they should show up now.When I created my spreadsheet, this was all new territory for me. I did it to help me get my head wrapped around it. I downloaded yours and look forward to playing with it after reading the info you linked to. It will probably be a few days before I get a chance to dive in between my work going crazy and running to doctor appointments, I don't get much else done. I really thought this would be a more popular subject but I don't think very many people are willing to put in the effort to try and understand the subject. Thanks for your info and commenting.
@2Old2Rodeo Great thanks.....lucky you have work we are still in lockdown in NZ up to our 4th week at home,hope you are well,
yes there seems to be not much info out there, the biggest problem I have is if you are arming for a DCR of 8.3:1 the SCR is not that high say around 9.2:1 which
does not sound like a high compression engine to me, I have a couple of good books and they both say stay around the 9:1 using your Premium 91AKI
(our 96 Mon) with Iron heads and 9.5:1 with Alloy heads, there are people on youtube claiming upto 13:1 with alloy heads on pump gas, there ignition must be retarded to compensator or they did the calculations wrong, here is another little program to double check your figures download it from his web site and try it,
ua-cam.com/video/vgclz3FOq_Q/v-deo.html Cheers Brett
@@kermets I am at 11.1 to 1 with cast iron heads. I decided to go with E85 for fuel. I have about 2 hours run time on the run stand and everything looks and sounds good. I have to tie up a few loose ends and then I hope to get it on an engine dyno to test and tune. I will get back to you once I have a chance to digest your info.