Previous Thread
Next Thread
Print Thread
methanol and boost... compression ratio limitations #1578602
02/13/14 05:18 PM
02/13/14 05:18 PM
Joined: May 2008
Posts: 322
San Diego, CA, United States
Texas_Charger Offline OP
enthusiast
Texas_Charger  Offline OP
enthusiast

Joined: May 2008
Posts: 322
San Diego, CA, United States
Hello all,

I've been playing around with numbers and researching for quite some time, so I figured I'd see what you all thought.

The engine in question is a low deck 470 big block stroker with a 10:1 static compression ratio and stealth aluminum heads.

With the implementation of a methanol injection system such as a Snow Performance kit that utilizes a 50/50 water methanol mixture, would 6 lbs of boost be attainable on 91 octane pump gas without detonation issues?


1971 Dodge Charger SE 470/727/3.91 Suregrip
2016 Dodge Challenger Hellcat, 6-speed
1980 Pontiac Trans Am, Y84, WS6
2002 Ram 2500 Cummins/6-speed/2WD/QC
1971 Ford F-350 Ranger

Re: methanol and boost... compression ratio limitations [Re: Texas_Charger] #1578603
02/13/14 06:33 PM
02/13/14 06:33 PM
Joined: Dec 2006
Posts: 235
Tucson AZ.
RADAMX Offline
enthusiast
RADAMX  Offline
enthusiast

Joined: Dec 2006
Posts: 235
Tucson AZ.
throw away the injection kit and just run it on E-85 problem solved

Re: methanol and boost... compression ratio limitations [Re: Texas_Charger] #1578604
02/13/14 08:46 PM
02/13/14 08:46 PM
Joined: Aug 2003
Posts: 43,195
Bend,OR USA
C
Cab_Burge Offline
I Win
Cab_Burge  Offline
I Win
C

Joined: Aug 2003
Posts: 43,195
Bend,OR USA
Quote:

Hello all,

I've been playing around with numbers and researching for quite some time, so I figured I'd see what you all thought.

The engine in question is a low deck 470 big block stroker with a 10:1 static compression ratio and stealth aluminum heads.

With the implementation of a methanol injection system such as a Snow Performance kit that utilizes a 50/50 water methanol mixture, would 6 lbs of boost be attainable on 91 octane pump gas without detonation issues?


I have ran as much as 7 lbs boost on a iron headed pump gas 426 hemi street hemi motor with no problems. You shouldn't need to add the injection at that level of boost The best thing to do is to start with the total timing limited to 22 degrees before top dead center(with a very cold spark plug) at WOT and then slowly, one degree at a time advance the timing until you start to see black or shiny specs on the center porcelyne (SP?) in the spark plugs, once you get it there then back the timing up 1 or 2 degrees Another good option is to use a boost timing retard module that will back the timing up for you automatically so it will drive nice under vacume and still protect the motor under boost


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: methanol and boost... compression ratio limitations [Re: Cab_Burge] #1578605
02/13/14 09:15 PM
02/13/14 09:15 PM
Joined: Nov 2010
Posts: 1,397
Carson City, Nevada
Biginchmopar Offline
pro stock
Biginchmopar  Offline
pro stock

Joined: Nov 2010
Posts: 1,397
Carson City, Nevada
I have built a few motors and used e-85 - 10:1 compression + 20lbs of boost.


Re: methanol and boost... compression ratio limitations [Re: Texas_Charger] #1578606
02/13/14 10:03 PM
02/13/14 10:03 PM
Joined: Oct 2003
Posts: 7,506
Az
Crizila Offline
master
Crizila  Offline
master

Joined: Oct 2003
Posts: 7,506
Az
Quote:

Hello all,

I've been playing around with numbers and researching for quite some time, so I figured I'd see what you all thought.

The engine in question is a low deck 470 big block stroker with a 10:1 static compression ratio and stealth aluminum heads.

With the implementation of a methanol injection system such as a Snow Performance kit that utilizes a 50/50 water methanol mixture, would 6 lbs of boost be attainable on 91 octane pump gas without detonation issues?


Assume you are adding a blower to a already built motor - 10:1CR? Also don't know where you are getting your 50/50 mix from unless it is an aftermarket mix from Snow, etc, cause windshield solvent is about 32% - and that's for winter blend. At any rate, the big variable is the pump gas #. I have seen it all over the place - and that's all over the place. So, you better cut yourself a level of margin. Are you running a blower cam - 114LSA or there abouts? To answer your question, yes, you can run 91 with injection and the timing cut way back - IMO. The question you have to ask yourself is the power gain trying to accommodate 91 octane fuel worth the cost of adding a very under utilized power adder - blower. Of coarse there is always the "WOW" factor.


Fastest 300
Re: methanol and boost... compression ratio limitations [Re: Texas_Charger] #1578607
02/13/14 10:04 PM
02/13/14 10:04 PM
Joined: Oct 2007
Posts: 3,978
Hilltown Pa
1967dartgt Offline
master
1967dartgt  Offline
master

Joined: Oct 2007
Posts: 3,978
Hilltown Pa
Yes you can do that, but you can make more hp with less compression and more boost.


Brett Miller W9 cnc'd heads
STR Chassis fabraction
Re: methanol and boost... compression ratio limitations [Re: Texas_Charger] #1578608
02/14/14 12:59 PM
02/14/14 12:59 PM
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Mr.Yuck Offline
Not enough dumb comments...yet
Mr.Yuck  Offline
Not enough dumb comments...yet

Joined: Jan 2003
Posts: 24,562
Brookeville, Md
I ran 93 w/ 6psi of boost, no cooler and no Meth/H2O, however that was a 9:1 cast psiton motor and I left a lot on the table. I did have an MSD boost retard that dropped the timing 1-3* per lb of boost. I like using that instead of locking in in at 22*. I run the Snow kit on this car (N/A 440-6) and it works. I use regular washer fluid but you can buy the stuff from Snow direct. I guess you could always add alcohol to the store bought. I'd try E85 but I have no idea where a station is that sells it and unless you have a few close it could become a PITA. Whatever you do make sure you are getting enough fuel in DAMHIK.


[IMG]http://i66.tinypic.com/pui5j.jpg[/IMG]
Coming soon!!!!






Powered by UBB.threads™ PHP Forum Software 7.7.1