HPI Monster Truck Forum Talk about HPI monster trucks here. The infamous Savage 21, SS, .25 or any other HPI MT. You can optionally discuss HPI in our general MT discussion forum if you prefer.
View Poll Results: A poll
30%
26.67%
20%
57.78%
other
15.56%
Voters: 45. You may not vote on this poll

30% or 20%

Reply

Old 12-25-2004, 10:54 PM
  #1  
Chris58
Junior Member
Thread Starter
 
Join Date: Sep 2004
Location: Tunnel Hill, GA
Posts: 20
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default 30% or 20%

Do you use 20% nitro or 30%, and why?
Chris58 is offline  
Reply With Quote
Old 12-26-2004, 05:16 AM
  #2  
neb
Senior Member
 
Join Date: Jul 2004
Location: South East, UNITED KINGDOM
Posts: 194
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

I use 20% because HPI recommend it
neb is offline  
Reply With Quote
Old 12-26-2004, 06:08 AM
  #3  
Frost_
Senior Member
My Feedback: (1)
 
Frost_'s Avatar
 
Join Date: Feb 2004
Location: Richmond, VA
Posts: 4,000
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

30, because it makes a noticeable difference over 20.... step down a range on the plug; an A5 for example.
Frost_ is offline  
Reply With Quote
Old 12-26-2004, 06:20 AM
  #4  
Nitro Driver
Member
 
Join Date: Dec 2004
Location: Giza, EGYPT
Posts: 78
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

20% , Good performance + good engine life
Nitro Driver is offline  
Reply With Quote
Old 12-26-2004, 06:30 AM
  #5  
in2deep_2
Junior Member
 
Join Date: Dec 2004
Location: portsmouth, VA
Posts: 7
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

I use 20%. Talking to a couple of guys hat have been around for awhile swear by 20% unless racing. 30% will increase performance if you use a colder plug but has less lubrication.
in2deep_2 is offline  
Reply With Quote
Old 12-26-2004, 08:52 PM
  #6  
stevblutu15
Senior Member
 
Join Date: Aug 2002
Location: W. Long Branch, NJ
Posts: 1,059
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

20, not enough money for 30 haha
stevblutu15 is offline  
Reply With Quote
Old 12-26-2004, 09:19 PM
  #7  
Frost_
Senior Member
My Feedback: (1)
 
Frost_'s Avatar
 
Join Date: Feb 2004
Location: Richmond, VA
Posts: 4,000
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

ORIGINAL: in2deep_2

I use 20%. Talking to a couple of guys hat have been around for awhile swear by 20% unless racing. 30% will increase performance if you use a colder plug but has less lubrication.
Nope, sorry.

The RACE blends of a same brand will be the same from 20 to 30...

O'Donnell (what I swear by) RACE has 12% oil no matter whether you get 20 or 30 %.
Frost_ is offline  
Reply With Quote
Old 12-26-2004, 10:51 PM
  #8  
fernandorussell
Senior Member
 
Join Date: Dec 2003
Location: santiago, DOMINICAN REPUBLIC
Posts: 244
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

so it is totally safe and non life-reducting to run 30% on the s25?
fernandorussell is offline  
Reply With Quote
Old 12-27-2004, 02:37 PM
  #9  
fernandorussell
Senior Member
 
Join Date: Dec 2003
Location: santiago, DOMINICAN REPUBLIC
Posts: 244
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

so is it or is it not?

thanks.
fernandorussell is offline  
Reply With Quote
Old 12-27-2004, 03:11 PM
  #10  
Frost_
Senior Member
My Feedback: (1)
 
Frost_'s Avatar
 
Join Date: Feb 2004
Location: Richmond, VA
Posts: 4,000
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

In the time that I have invested in each I don't see a difference, but there are SO MANY VARIABLES that affect engine life that [engine life] is nearly impossible to predict.
Frost_ is offline  
Reply With Quote
Old 12-28-2004, 10:44 AM
  #11  
savageman90
Senior Member
My Feedback: (12)
 
Join Date: Mar 2005
Location: appleton, WI
Posts: 990
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

i use 20% because that is what my other takes and i don't feel like buying 30% too
savageman90 is offline  
Reply With Quote
Old 12-28-2004, 09:42 PM
  #12  
crankshaft
Member
 
Join Date: Nov 2004
Location: baltimore, MD
Posts: 73
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

if 30% is okay and I run 20, I could probably increase the conpression then. it would definetly help the response, and increase the efficiency of the engine. that could be almost as good as running more nitro. but then again could it possibly slow burn rate at high rpms, or at that, is it possible for a 2 stroke to have detonation before top dead center? frost, is that why you say to step down on the glow plug? i ask because you seem to know what you are talking about. I would trust your jugement over most.
crankshaft is offline  
Reply With Quote
Old 12-29-2004, 12:12 AM
  #13  
Frost_
Senior Member
My Feedback: (1)
 
Frost_'s Avatar
 
Join Date: Feb 2004
Location: Richmond, VA
Posts: 4,000
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

ORIGINAL: crankshaft

if 30% is okay and I run 20, I could probably increase the conpression then. it would definetly help the response, and increase the efficiency of the engine. that could be almost as good as running more nitro. but then again could it possibly slow burn rate at high rpms, or at that, is it possible for a 2 stroke to have detonation before top dead center? frost, is that why you say to step down on the glow plug? i ask because you seem to know what you are talking about. I would trust your jugement over most.
A few things... The stock 25 comes with 3 shims, I have found that virtually anyone on 20% or lower can safely remove 1 and most (but you're on your own here) can remove 2 even at 20%. There is a slight increase in power gained by the added compression, and many people say this also makes the truck easier to start.

This does not by any means come close to adding 10% nitro to your fuel though. Most all big-blocks can safely run 30%, the manufacturer's steer you into a safety cushion at 20%... The stock 25 (again, as with most BBs) can run 30% nitro with a McCoy mc59 or an OS A5 or other equivalent heat range safely. The 30% race makes the most power, and this is easily visually verified. Whenever you change fuels you will have to retune. If you go up in nitro the engie will run VERY cool and have to be leaned out.

Pre-ignition/detonation can occur in 2 strokes, it can range from annoying and power-robbing to destructive (bent rod, rod that fails at the crank, etc). Obviously if you pull a few shims off of your 25 don't jump to 30%, but it can be run just fine with the stock shim arrangement.
Frost_ is offline  
Reply With Quote
Old 12-29-2004, 08:23 AM
  #14  
fernandorussell
Senior Member
 
Join Date: Dec 2003
Location: santiago, DOMINICAN REPUBLIC
Posts: 244
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

Frost,on tower the discription for the mc59 say that its got a hot element and it disigned for use with low to medium nitro fuel.
Aren't you suposed to use a medium cold plug with 30% on the S25?
Explain please.

thanks.
fernandorussell is offline  
Reply With Quote
Old 12-29-2004, 12:44 PM
  #15  
Frost_
Senior Member
My Feedback: (1)
 
Frost_'s Avatar
 
Join Date: Feb 2004
Location: Richmond, VA
Posts: 4,000
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

ARRRG I MEANT an Mc9, but to be honest I think that the 8 may be a little better; the 9 is cold and the 8 is about a med-cold if I remember correctly...
Frost_ is offline  
Reply With Quote
Old 12-30-2004, 04:13 PM
  #16  
fernandorussell
Senior Member
 
Join Date: Dec 2003
Location: santiago, DOMINICAN REPUBLIC
Posts: 244
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

What if you run 30% using an os #8?
will it run too hot?
will it run better?

thanks.
fernandorussell is offline  
Reply With Quote
Old 12-30-2004, 04:16 PM
  #17  
fernandorussell
Senior Member
 
Join Date: Dec 2003
Location: santiago, DOMINICAN REPUBLIC
Posts: 244
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

also is the duratrax gold a good plug for running 30% nitro?

thanks.
fernandorussell is offline  
Reply With Quote
Old 12-30-2004, 04:19 PM
  #18  
fernandorussell
Senior Member
 
Join Date: Dec 2003
Location: santiago, DOMINICAN REPUBLIC
Posts: 244
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

what about the duratrax carbon colored?

sorry for all the posts, im a little confused on the plugs

thanks.
fernandorussell is offline  
Reply With Quote
Old 12-30-2004, 05:36 PM
  #19  
8000ft
Senior Member
 
Join Date: May 2003
Location: winterpark, CO
Posts: 808
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

i've run monster hp 30% exclusively in my engines (wasp .26s) for the past two years and the ONLY plug that i have found that works well and lasts is the os r-5. NOT the a-5.
8000ft is offline  
Reply With Quote
Old 12-30-2004, 06:14 PM
  #20  
fernandorussell
Senior Member
 
Join Date: Dec 2003
Location: santiago, DOMINICAN REPUBLIC
Posts: 244
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

what happened with the a5
What about the other ones i mencioned
im talking about the s25 in a savage
thanks anyway 8000ft

thanks.
fernandorussell is offline  
Reply With Quote
Old 12-30-2004, 09:07 PM
  #21  
stevblutu15
Senior Member
 
Join Date: Aug 2002
Location: W. Long Branch, NJ
Posts: 1,059
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

i buy all different plugs and have never noticed a difference in performance. how do they really work?
stevblutu15 is offline  
Reply With Quote
Old 12-30-2004, 10:12 PM
  #22  
Smokin240sx
Senior Member
 
Smokin240sx's Avatar
 
Join Date: Nov 2004
Location: warner robins, GA
Posts: 232
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

I USE 20% BECAUSE IT WAS THE RECOMMENDED FUEL BUT IN THE DECEMBER ISSUE OF RC DRIVER THEY COMPARED THE TWO AND THE 30% FUEL WAS THE TOP PERFORMER.
Smokin240sx is offline  
Reply With Quote
Old 12-30-2004, 11:09 PM
  #23  
fernandorussell
Senior Member
 
Join Date: Dec 2003
Location: santiago, DOMINICAN REPUBLIC
Posts: 244
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

where can i see that issue Smallblock?

thanks.
fernandorussell is offline  
Reply With Quote
Old 12-30-2004, 11:42 PM
  #24  
Smokin240sx
Senior Member
 
Smokin240sx's Avatar
 
Join Date: Nov 2004
Location: warner robins, GA
Posts: 232
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

IM SORRY IT'S THE JANUARY 2005 ISSUE 30% FUEL HAS MORE TOURQUE AND BHP.
Smokin240sx is offline  
Reply With Quote
Old 12-30-2004, 11:53 PM
  #25  
fernandorussell
Senior Member
 
Join Date: Dec 2003
Location: santiago, DOMINICAN REPUBLIC
Posts: 244
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: 30% or 20%

but where can i see it?

thanks.
fernandorussell is offline  
Reply With Quote

Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy