MP112/15lbs of boost on 402CID 600/700 to the wheels......video link
09-19-2007, 04:02 PM
#13
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Forget waiting on a TVS 2300 I want a mp112 on my stroker
Its probably the same as his engine temp or higher
Originally Posted by thunder550
Good god I'd hate to see what his IAT's were on that setup 
Is that even possible? I'm thinking
Is that even possible? I'm thinking
09-19-2007, 04:58 PM
#14
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wow bet it doesn't make more then 650fwhp though. All this shows is improper cam selection. A decent 408 should be way out of the realm of using a 112.
09-19-2007, 07:41 PM
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I agree with krambo on this one, must be a false boost gauge reading or map sensor way out of calibration somehow, or just doing the map to boost conversion math wrong.
09-20-2007, 12:46 AM
#19
Originally Posted by tlaselva
Funny, I saw condensation on the top of his Maggie after he got back to the shop after a few pulls. ECS Dual Nozzle Alky kit does wonders!
So let's think about this for a minute. If a 3.0" pulley makes about 9-10 psi on a small overlap cam in a 5.3, and a 2.8" pulley makes about 9-10 psi on a small overlap cam in a 6.0, we can extrapolate this into the theory that a 2.6" pulley (if it were even available) would make 9-10 psi on a small overlap cam in a 6.7 (402/408). (I'm assuming a front drive Radix here, for simplicity)
Let's go back to the 5.3 and 6.0 for a minute. Every drop of .2" in the pulley yields roughly a 2 psi increase. Let's ignore belt slip for a minute, and assume that this means that every .1" drop in pulley diameter yields a 1 psi increase in boost pressure. To get from 10 psi to 15 psi on the 402, we would have to drop from a 2.6" pulley to a 2.1" pulley. Again, this doesn't even account for belt slip, which would be enormous at that level (which is irrelevant anyway since you can't fit anything smaller than a 2.75" pulley, but I digress......)
So here we are, with a 2.1" pulley on our front drive/single pulley Radix on our 402 with no belt slip occurring. Completely impossible situation, but what the hell. Let's figure out how fast the blower is spinning anyway.
The stock crank pulley is roughly 7.5" diameter. 7.5/2.1 = 3.571. The supercharger is spinning 3.571 times faster than the engine. Since he doesn't say how fast he spins the engine, I'm going to assume a nice even number like 6000 RPM. At 6000 RPM, this means that our supercharger is spinning at roughly 21,426 RPM.
I'm not 100% positive on this, but I think I remember reading somewhere that the max allowable RPM's on the Radix-style blowers was about 18,000. Any faster than that and they ran the risk of damage from the rotors contacting each other. It's pretty safe to say that 21,500-ish isn't possible, which is why I call total
on this guy's results.
Last edited by thunder550; 09-20-2007 at 01:07 AM.
