Originally Posted by 1967rsss
Gm has to use what they own (eaton). The problem is heat soak form being made of metal, and being mounted to th top of the engine. Heat rises, metal obsorbs heat, transfers heat to air. Now when you compress air, the air becomes super heated from being compressed, so the air needs to be cooled to maintain performance and less prone to detonation. Now you have a heater core mounted inside the metal magnisun intake manifold to try and cool the air. The problem is, the intercooler (heater core), is heat soaked buy the engine, rendering it almost useless. This is why people use the methanol to try and reduce the heat soak.
GM tried a setup with a TT ZR1, nearly burnt the car down to the ground. heat rises, metal absorbs heat, transfers heat to air.... yes, and when a fi setup is using hot expanding gas to power it, that same heat can transfer the same way. the air charge should to be cooled in any FI setup. people use methanol/water injection and intercoolers to reduce heat soak and air temps. meth injection is nice in some aspects as you dont need a honking intercooler stuffed in somewhere.
Don't listen if you want, I have worked with these, and simular units for years. Yes the maggys give instant boost, but also inlet air temperatures of 180+ degrees. If you research the mustang, GTP, and other forums for cars that run these SC, you will see that people have made more hp, run faster times, with both centrifical SC and turbos on the same cars.
some have, some havent. I will say that 9 times out of 10 its easier to make more power with a turbo for the simple reason that if the turbo isnt cutting it, swap it out with a bigger one.
Now as far as a centrifugal SC, you can run more boost safely. The engine is most prone to detonation at peak torque. The higher you rev and engine, the safer it is to run more boost. This is because at higher RPM's the valve isn't open as long, so there is lees time to fill the cylinder, resulting in lower cylinder pressure. Also I have seen more hp and tq down low at lower boost levels due to cooler inlet air temps.
but at that same time your valves arent open as long, you are pushing more air thru them. and you are right about it being most suceptable to detonation near peak torque which is around peak VE with all other factors being equal.
The centrifugal and the maggy's are belt driven (fake turbos).
what he meant by it is that centrifugal s/c's are negative displacement s/c's and act like a turbocharger with a belt/gear drive instead of a shaft from the exhaust turbine.
Turbos are known to make the most HP per cubic inch, but there is some lag. I have race LS cars for over 10 years with all different set ups. I have raced NA stock cube, strokers, NOS, SC, and turbo. I can tell you first hand that the maggys are crap, ProChargers are ok, but theres nothing like turbos. You want driveabilty, reliability, TQ and HP to go fast in a heavy car, Turbos will all ways be the best bet. No belt slippage that both the maggy and all SC have when trying to make real power. The maggys are very asy to install, but it's about spending money wisely to get the best performance. BTW the APS turbo systems typically take about 40+ hours to install, but well worth it.
turbos are great ways of adding power, they benefit most from the numerous sizes that are available, which allows for installing whatever size you want on whatever engine you want. whereas s/cs are mostly made for specific motors.
I will be fabricating my own system on the camaro, but will wait until next winter. I want to play while most don't have the car and it's rare to see. It will take me about 100-150 hours to build, but I will enjoy the project.
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