Dyno results from “Bonneville” motor, 765 WHP, 900 CHP
#197
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I have an older G-Tech Pro. Thanks for the heads-up, I will go look at the new ones.
This looks interesting... http://www.velocitek.com/speedpuck/
...but it looks like it only displays in knots. I like the large display.
This looks interesting... http://www.velocitek.com/speedpuck/
...but it looks like it only displays in knots. I like the large display.
#198
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I understand what you mean by "used" 1.5L of oil- you pumped it out of the motor. Do address your crankcase pressure before you blow all the seals out of that motor! When the crankcase pressure comes down the piston rings will seal better and you will also gain HP.
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So..this is Sept 14th-17th..
Im strongly considering flying out in the Bonanza for this, if I can find three more peeps in NorCal who wanna go check this out.
Its about a 2.5hr flight to Wendover each way.
http://www.airport-data.com/aircraft/photo/104720.html (this one to be exact)
Im strongly considering flying out in the Bonanza for this, if I can find three more peeps in NorCal who wanna go check this out.
Its about a 2.5hr flight to Wendover each way.
http://www.airport-data.com/aircraft/photo/104720.html (this one to be exact)
#203
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Originally Posted by Carl Fausett
my stock speedo will stop at 165ish and I don't know what it'll do above that.
Me - How did it go?
Driver - Great, the car handled perfectly
Me - How fast did you get it up to?
Driver - M
Me - M? How fast is M?
Driver - I'm not sure, but that's where the needle was pointing.
No, this wasn't an 85 speedo
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#204
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Here are some photos of the new exhaust system we just finished for the Bonneville setup.
The primary goal was reducing crankcase pressure caused by exhaust back-pressure, and we succeeded at that.
Last month we were still were running last year's exhaust system; the same 3.0" dual exhaust I ran on last years' 650 HP 16v motor. On this 900 HP motor, we noticed crank pressure go up, so we knew we had too small of an exhaust system for this motor.
Here are the stats from the two exhausts on the same engine:
3.0 dual exhaust: 18 psi in the intake plenum, 2.8 psi in the crankcase at 6800 rpm, and 4 psi of exhaust back-pressure at 6800 rpm.
3.5" dual exhaust: 15 psi in the intake plenum, 2.0 psi in the crankcase at 6800 rpm, and 1 psi of back-pressure at 6800 rpm.
Note that the exhaust was the only change. We ran the same pulleys, supercharger, etc. The difference in intake pressure between the 3.0" and 3.5" exhaust shows that the 3.0" setup was so restrictive at this level (900 HP) that it was backing up thru the cylinders and lowering our volumetric efficiency.
Now the supercharger does not have to work so hard to overcome the back-pressure, the parasitic losses are less, and the engine breathes better.
Made from all 304 SS, .065 wall mandrel elbows, .049 wall straights. V-band clamps instead of header flanges.
Some photos represent work-in-progress. Thats why only the last photo shows the balance tube section.
The primary goal was reducing crankcase pressure caused by exhaust back-pressure, and we succeeded at that.
Last month we were still were running last year's exhaust system; the same 3.0" dual exhaust I ran on last years' 650 HP 16v motor. On this 900 HP motor, we noticed crank pressure go up, so we knew we had too small of an exhaust system for this motor.
Here are the stats from the two exhausts on the same engine:
3.0 dual exhaust: 18 psi in the intake plenum, 2.8 psi in the crankcase at 6800 rpm, and 4 psi of exhaust back-pressure at 6800 rpm.
3.5" dual exhaust: 15 psi in the intake plenum, 2.0 psi in the crankcase at 6800 rpm, and 1 psi of back-pressure at 6800 rpm.
Note that the exhaust was the only change. We ran the same pulleys, supercharger, etc. The difference in intake pressure between the 3.0" and 3.5" exhaust shows that the 3.0" setup was so restrictive at this level (900 HP) that it was backing up thru the cylinders and lowering our volumetric efficiency.
Now the supercharger does not have to work so hard to overcome the back-pressure, the parasitic losses are less, and the engine breathes better.
Made from all 304 SS, .065 wall mandrel elbows, .049 wall straights. V-band clamps instead of header flanges.
Some photos represent work-in-progress. Thats why only the last photo shows the balance tube section.
Last edited by Carl Fausett; 05-24-2011 at 11:27 PM.
#208
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I agree. For the street you would have less bottom end (IMO)
For the top end on a big block it is what you need.
Maybe a foot of 2.5" in the center on each side would help street bottom end perf.
But before I buy any thing anymore I'm asking some of the guys on here that would know for sure
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#209
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Amongst engine builders it is commonly accepted that the right size of tailpipe for a 750 hp engine is 5" or dual 3,5". For a 1000+ hp engine the tailpipe size need to be increased to dual 4".
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Carl, at post 204 it looks like you have your front 'axle' stands underneath the thin-walled box section that simply provides a bit of stiffening to the floor pan. Maybe you have stiffened this section or done some other modification (maybe U-section steel supports atop axle stands? - hard to tell from the photos) to make this an OK lifting place.....??