How Much Boost????
 

Ok all you supercharged guys post your hot setups.

Static compression?
Boost pressure?
Displacement?
Heads?
Cam?
Intercooled?
Type of supercharger?
Engine Hours?

Trying to see how many actually run over 8lbs of boost? on 8 to 1 motors. Pump gas.

Thanks in advance.

Re: How Much Boost????
 

8-1,procharger aw504 intercooler,merlin heads,arp head studs,merlin block,540 ci,9 psi boost.cam motion hyd roller 622 lift,228/238 at .050,95 hours w/no problems,93 octane,felpro marine head gaskets

Re: How Much Boost????
 

Whipple charger non intercooled 5lbs boost,383 sbc,8:1comp, Dart pro 1 aluminum heads, custom comp cam hydraulic roller, 1050 pro systems dominator running 93 octane pump gas 24 hours, made the mistake of not running stud girdle and broke a exhuast stud, nothing else.

Re: How Much Boost????
 

Good Question!

So far my hottest setup is on Dean Nickerson's boat:

8.25:1 compression ratio
8.5 psi intake manifold boost
498 CID (stroked GM 454)
Ported GM cast iron heads, FelPro head gasket
Dart single plane intake, Nickerson carb
Solid roller, ~250 @ 0.050"
Rtech Supercooler
Vortech V-4, J-trim, ~45,000 RPM
Engine hours unknown, had a B&M 250 before this.
Measured intake air temperatures:

After blower - 225F
After intercooler - 80F
Cooling water - 60F

This setup has been dynoed at 950 HP @ 6000 RPM using 30 degrees total timing and 92 octane. I have another customer with two similar 498 engines in a new 43 Black Thunder. He used a hydraulic roller cam and made 875 HP @ lower RPM/lower boost.

I know your question is aimed at longevity/reliablity at these boost levels. Since boost can be up or down depending on cylinder heads, cam and displacement, I think reliability is better measured against the HP being delivered. For example, 8.5 psi boost on Nickerson's engine results in more cylinder pressure than 8.5 psi boost on stock heads with a hydraulic roller cam, even though he uses less compression. It is easy to spin the blower faster on the stock engine to try and up the cylinder pressure, but with this comes more heat, so the overboosted stock engine may hit the detonation limit before Nickerson's would.

In any case, the key to avoiding detonation is to keep intake temperatures as low as possible. This is achieved mostly by having a large, efficient intercooler, but also by lowering the restrictions to air flow that must be overcome by the blower. If you can do that, then the blower doesn't have to work as hard and you have less heat to begin with.

It would also be interesting to know what head gaskets people are having the best luck with on these high boost engines. I think Nickerson used Fel Pro. I remember asking him and he wasn't doing anything special. I hear the Cometic gasket is working well on nitroused drag car engines.

Re: How Much Boost????
 

Wow Tomcat your chiller drops it by 145 degrees.

My example is

8.0 to 1 static compression
9psi manifold boost at 5000rpm
540cubic inch 4.5bore 4.25stroke
Fully ported merlin cast irons with cometic gaskets
Crane hydraulic roller #741 234¢@50
Richard lee intercooler with Whippile 24fin per inch cupranickeal cores
Mooneyham 10-71 overdriven 15% to achieve 9lbs
15hrs
No idea what horsepower is never dynoed

Notice the amount I have to drive the blower just to get 9lbs
The restriction of the intercooler combined with cam duration, ported heads are most likely the reason. I would be interested in knowing my discharge air temp under the cooler.

Correct me if I'm am wrong isn't pump gas only good for 12-1 combined compression?

Keep the setups coming Guys!!!!!

Gerry

Re: How Much Boost????
 

Nice info here.http://www.kuhlsuperchargers.com/tech%20p05.htm

Re: How Much Boost????
 

8 - 1 comression
Ported Merlin Heads
509 Cu Inches
Crane Roller Cam & Roller Rockers
B & M 250 Blower, 7 lbs boost
Superchiller Intercooler
2 Nickerson-Built Holly 750's
MSD Ignition

Supposed to be around 700 HP

Re: How Much Boost????
 

I'm using a twin turbo setup.
7.5:1 static
20lbs boost
ported dart 360 heads
solid roller cam
modified superchiller intercooler
50 hrs

Re: How Much Boost????
 

check300,do you boat at hardy pond,i think you blew by me doin 90-95 last year,Smitty

Re: How Much Boost????
 

That was me....going there tomorrow.