C5 Forced Induction/Nitrous C5 Corvette Turbochargers, Superchargers, Centrifugal, Twin Screw & Roots Blowers, Twin Turbo Kits, Intercoolers, Wet & Dry Nitrous Injection, Meth
Sponsored by:
Sponsored by:

6PSI Max With Meth Only?

Thread Tools
 
Search this Thread
 
Old 11-10-2017, 09:07 PM
  #1  
doug_dayson
Racer
Thread Starter
 
doug_dayson's Avatar
 
Member Since: May 2002
Location: SF Bay Area CA
Posts: 454
Received 12 Likes on 12 Posts

Default 6PSI Max With Meth Only?

Is anyone running a mild 5PSI - 6PSI setup on a stock LS1 with Meth only (no IC), like the old Carroll C4 setups?

The theory was you'd lose the pressure drop across the IC/Piping, and use a bigger pulley to avoid higher IAT's and parasitic losses etc?

I'm only looking for 100 HP - 120 HP or so for higher altitude passing abilities with a 100% street driven FRC, no racing of any kind. In addition I live in CA where my exhaust options are extremely limited (no LT's), so getting 100HP N/A isn't as easy as it is else where (and I want my economy and driveability/reliability to remain unchanged, so no big cams etc).

Is this Meth only idea still viable these days for mild builds?

TIA...
Old 11-11-2017, 05:19 AM
  #2  
typeav
Racer
 
typeav's Avatar
 
Member Since: May 2007
Posts: 478
Received 57 Likes on 48 Posts

Default

You can get away with it.....I thought about this idea many times to cut corners but doesn't seem worth it after doing an extensive research.

https://www.procharger.com/learn-mor...ing-technology
Attached Images  
The following users liked this post:
doug_dayson (11-11-2017)
Old 11-11-2017, 11:54 AM
  #3  
doug_dayson
Racer
Thread Starter
 
doug_dayson's Avatar
 
Member Since: May 2002
Location: SF Bay Area CA
Posts: 454
Received 12 Likes on 12 Posts

Default

Originally Posted by typeav
You can get away with it.....I thought about this idea many times to cut corners but doesn't seem worth it after doing an extensive research.

https://www.procharger.com/learn-mor...ing-technology
Hmmm, most likely, and of course you'd have to keep the Meth reservoir topped up etc which can be a PITA, but with regards to the ATI graphic, by my calculation we'd lose around 44* +- off the top at the SC Head's output due to the lower boost needed.

We're looking for 5 - 6 PSI with no IC pressure drop, and IC pressure drop is usually a couple of PSI as I understand it, which means the ATI head is outputting around 10 PSI pre-IC +- in their graphic?

We'd also lose whatever parasitic HP losses associated with the difference in pulley sizes from 10 PSI to 5-6 PSI for the modest increase in power we're looking for?

I'm thinking I could make 100HP easily at 5 - 6 PSI tuned safely rich sans Meth (stock 345HP LS1), so if the Meth failed the engine would be safe for typical short WOT bursts on the street (no long top-end pulls etc), and then the Meth would be added on top for long-term reliability's sake?

I'm really just looking for a cheaper/easier and lighter weight install seeing all of this stuff hangs off the nose of the car, and my power needs are modest (and they're going to stay that way, honest!), plus I have a C5 Z06 clutch and that's it, so I don't want to kill the stock C5 drivetrain.

Thanks, and I'm looking forward to some of you experts poking holes in my theory LOL!
Old 11-11-2017, 12:05 PM
  #4  
typeav
Racer
 
typeav's Avatar
 
Member Since: May 2007
Posts: 478
Received 57 Likes on 48 Posts

Default

Let me clarify something, methanol is only injected at certain boost, rpm or voltage level, is not like injecting methanol and water all the time to keep the engine cooler. In the middle of the day in traffic your engine is going to suffer.

There are many cars model that came from the factory with no intercoolers and according to Vortech research intercoolers are not necessary for less than 9 psi. You will reach your goal with or without it but how efficient and longer you want your engine to last is up to you.
Old 11-11-2017, 12:19 PM
  #5  
typeav
Racer
 
typeav's Avatar
 
Member Since: May 2007
Posts: 478
Received 57 Likes on 48 Posts

Default

See the link for more details

https://www.procharger.com/learn-mor...ing-technology

THE FUNDAMENTAL SOLUTION

All non-intercooled superchargers operate with an intake manifold temperature in the general range of 115°-200° above ambient (outside air) temperature at 8 psi of boost. At the same boost level, an Intercooled ProCharger operates at only 28° above ambient! This tremendous advantage from cooler air is just like the difference between driving your car on a cold winter's day vs the blistering heat of summer! Thats a real advantage that yields real performance. It helps to understand that no supercharger alone will ever begin to match the system efficiency of an intercooled supercharger system. This is simply because compressing air creates heat, as dictated by the laws of physics (Boyle's Gas Law). Even in the case of "perfect compression" (100% adiabatic efficiency, which is physically impossible without an intercooler - see chart), air temperature would increase by approximately 71° at only 8 psi, while the lower (40-80%) efficiencies of all non-intercooled superchargers produce substantially higher temperatures. Intercooled ProCharger systems are the fundamental, OEM solution - because not only is less heat created when the air is compressed, the majority of this heat is actually removed through intercooling.

The bottom line is that intercooled boost is substantially more powerful and safe for your engine than hot, non-intercooled boost. Now that technology has developed to the point that gear-driven superchargers are powerful enough to reliably blow through an intercooler, it simply doesn't make sense not to intercool, especially for fuel injected applications running pump gas. In fact, for high compression engines or continuous duty applications, such as marine or towing, intercooling is absolutely essential for reliability.

In basic terms, compressing air creates heat, while intercooling removes heat. The illustration above may help to further explain the tremendous impact of intercooling upon supercharger system efficiency and engine intake temperatures.

BENEFITS OF INTERCOOLING

Greatly Reduced Intake Temperature
An 85°-200° drop in air temperature (dependent upon application) results in a reduced exposure to detonation, and virtually eliminates the "power fade" felt in back-to-back runs and extended pulls without intercooling

Full Timing
This reduction in temperature allows you to run factory (or close to factory) timing, and avoids the substantial horsepower loss inflicted by excessively retarded ignition timing

More Low-End Boost and Horsepower
The intercooler also acts as a passive wastegate, flattening the boost curve at higher rpm's and allowing more boost to be dialed in at lower rpm's

An Expanded Power Band
Full timing and forced induction keep the engine pulling hard to the redline

More Boost
Not only will you experience the above benefits at any boost level, you can also safely run substantially more boost when intercooled!

RELIABLE HIGH PERFORMANCE

Clearly, the only type of performance that matters is reliable performance, and detonation is the single biggest threat to engine reliability. The boost range for reliable performance, without detonation, can be determined by looking at the type of supercharger technology being considered, and the compression ratio of the motor. With a lower compression ratio, an engine can safely handle more boost, everything else being equal. Similarly, if the temperature of the compressed air is lower, an engine will have a much higher detonation threshold (the point at which fuel ignites without a spark), and will be able to safely handle more boost.

The chart below helps to illustrate how the overall efficiency of the entire supercharger system can be increased by both leading edge supercharger efficiency and the use of intercooling. Simply locate an engine's compression ratio at the bottom of the chart and trace upwards to determine the maximum reliable boost level. The amount of heat produced (adiabatic effiency) by each supercharging technology is what determines the boost limitation. While gear-driven centrifugal is clearly the superior supercharger technology, it is also clear that the biggest benefit comes from intercooling. These calculations assume moderate timing, 92 octane pump gas, and a good supply of fuel to the cylinders.

As mentioned previously, detonation is the single biggest threat to engine reliability. It is heat and detonation that cause blown head gaskets and burned pistons, not boost. Achieving maximum performance from a given engine while avoiding detonation requires the right combination of intake air temperature, timing and fuel quality. For example, without intercooling a stock 5.0 with 9.5:1 compression ratio can only hold 5-6 psi of boost before detonation becomes a problem. The only way to safely run more than 6 psi of boost and still make a meaningful increase in power without an intercooler is by using racing fuel to avoid detonation.

DETONATION

We've all heard of this, but what is it? Detonation, or engine knock, occurs simply when fuel pre-ignites before the piston reaches scheduled spark ignition. This means that a powerful explosion is trying to expand a cylinder chamber that is shrinking in size, attempting to reverse the direction of the piston and the engine. When detonation occurs, the internal pneumatic forces can actually exceed 10x the normal forces acting upon a properly operating high performance engine. Detonation is generally caused by excessive heat, excessive cylinder pressure, improper ignition timing, inadequate fuel octane or a combination of these. Of the previous, excessive heat is usually the culprit. As an engine is modified to generate more power, additional heat is produced. Today's pump gas will only tolerate a finite amount of heat before it pre-ignites and causes detonation.
Old 11-11-2017, 02:51 PM
  #6  
StatmanRN
Burning Brakes
 
StatmanRN's Avatar
 
Member Since: Sep 2011
Location: odessa FL
Posts: 764
Received 19 Likes on 18 Posts
Default

It would be interesting to take IAT sensor readins at the turbo inlet, the intercooler inlet and manifold.I agree intercooling is desirable but I think under real world conditions, particularly with higher ambient temps, the effeciancy iprobably isnt as high as claimed.
Comparing that to pure meth addition only would depend on where you are injecting and how much. It has a pretty good latent heat of vaporization.
Bottom line is at that boost level I think it would work.
Old 11-12-2017, 01:28 AM
  #7  
romandian
Drifting
 
romandian's Avatar
 
Member Since: Nov 2014
Location: Switzerland
Posts: 1,867
Received 88 Likes on 78 Posts
Default

as far as i remember intercooled supercharger systems appeared about 10-15 years ago. thats probably when the chinese got in to the intercooler business. earlier engines would not take more than 0.5 bar of boost anyway, so no intercooling was needed.

use water to cool the charge.

Get notified of new replies

To 6PSI Max With Meth Only?




Quick Reply: 6PSI Max With Meth Only?



All times are GMT -4. The time now is 05:00 PM.