Stiegemeier Is Not Recommending 4#lower
- Thread starter dynobobstieg
- Start date
Well, we know that boost does directly relate to blower speed. And engine RPMs relate to blower speed as well. What you're saying would only apply IF people kept engine RPMs (with, say, 14-17 lbs. of boost) under 5,000 RPMs. Which we know ain't gonna happen. The engine is surely going to see 6,000 RPMs in a WOT situation. So this is why boost is definitely an issue. The more boost, the faster the blower is going to spin at that 6,000 RPM level.sedanman said:
Remember that Crankshaft Pulley Size over Upper Pully Size = Ratio. And Ratio X Engine RPM = Blower RPM. Which is why using a larger crankshaft pulley and a smaller upper pulley creates more boost. Which in turn spins the blower faster. The faster the engine RPMs the faster the blower spins. The higher the boost level the faster the blower will spin at a given engine RPM level. This creates heat and puts stress on the blower. Imagine what would happen if you tried to run 22 lbs. of boost with the Eaton at 6,000 engine RPMS? Or even 5,500 RPMS. So the higher the boost, generally the more stress you're putting on the blower components. So most people generally say that 16 lbs. of boost is the max for daily driving using the Eaton.
CobraBob said:
Bob, what happen to Apten, what is the comparison between the two porting styles? Thanks for your input.
Stiegemeier was doing the porting for Apten. I hope I have these details right. Apten was bought by MD Motorsports and the porting end stayed with Stiegemeier. As far as porting designs, there is a significant difference between the Stage 1/2 and the latest Stage 4. For one thing more material has been removed with Stage 4. You should contact Bob S. @ Stiegemeier for a more detailed explanation as far as the differences. Basically the differences equate to more power.
As a potential future customer, I wish somebody at Stiegemeiere would man up and say something already. Anything.
Modded Mystic said:Really?
I like my 6lb lower,3.1 upper combo. The car has never felt this strong before. A 2.76 upper and a #2 lower is the same ratio....what gives?
~Mark
Good point, Also, Doug from Billetflow recommend my 2.93/4# when I was on a port and it was fine. :beer:
sprsonic said:
Ditto....might go to the 3.1
dynobobstieg
New Member
I had stated earlier a 3.0 Upper with 4# Lower would be 16#s boost and ok-Well it was Assumed that a 2.93 upper and 4# lower is close to the same and what would be the difference-Then the next guy would figure more is better-That is not always the case. At up to 15#s of boost there are no fuel mods needed- Making tuning not so difficult.
At 16#s boost you will need a MAF extender ,BAP, spark plugs and after time a upgraded clutch-Making tuning more difficult.
At 17#s of boost you will need All Fuel Mods Big Air MAF, Focus Pumps or BAP,60# Injectors, Bigger Cooler, spark plug specific,selective fuel, Headers, CAT Hi Flo or Delete Uddated stronger clutch-Making tuning very difficult.
More boost more Heat when engine sensors read something unusual the react in a safe position-these areas must be datalogged and addressed individually.
To comment on my statement about boost I realize there are some out there who run 17#s boost very sucessfully. These individuals have worked very hard to gain the knowledge and experience to do this along with untold expenditures. I can not and would not expect these Cobra Warriors to pass on the recipe for Hi Boost Power.
These combos need many fuel mods and accessories- The biggest factor being an Ace Tuner. If your area is anything like ours- We now have 5 new dyno shops (within the last year) in a 5 mile radius- They are just starting their tuning learning curve.
At 16#s boost you will need a MAF extender ,BAP, spark plugs and after time a upgraded clutch-Making tuning more difficult.
At 17#s of boost you will need All Fuel Mods Big Air MAF, Focus Pumps or BAP,60# Injectors, Bigger Cooler, spark plug specific,selective fuel, Headers, CAT Hi Flo or Delete Uddated stronger clutch-Making tuning very difficult.
More boost more Heat when engine sensors read something unusual the react in a safe position-these areas must be datalogged and addressed individually.
To comment on my statement about boost I realize there are some out there who run 17#s boost very sucessfully. These individuals have worked very hard to gain the knowledge and experience to do this along with untold expenditures. I can not and would not expect these Cobra Warriors to pass on the recipe for Hi Boost Power.
These combos need many fuel mods and accessories- The biggest factor being an Ace Tuner. If your area is anything like ours- We now have 5 new dyno shops (within the last year) in a 5 mile radius- They are just starting their tuning learning curve.
:read:
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Stiegemeier said:
why is it at 16lbs you need a extender but at 17 you need a big air maf? isnt the whole point of the extender to stay with a stock maf but use it well past the 500hp mark in which they max?
also on 16 you state a BAP is needed. thats fine.. but on 17 you state focus pumps or a BAP... why not focus pumps at 16?
you also say you need headers at 17#'s... this is a false statement seeing bad03cobra went 10.0 all boost on stock manifolds...
and the offer still stands for doing the FEA and GPS test on the blowers...
I don't want to speak for Bob, but I would think that some of the mods he lists are those that are needed/recommended for an optimum setup from a performance/reliability standpoint. At least that is the way I would personally read it. Anyone who has a question specific to Bob's last post should simply call him for an explanation/clarification. He obviously is not online very often due to being so busy at his shop. So a posted comment may not get a response from him for days. Calling him might also bring about a faster response from him here. JMO.
2003 Silver
Banned
CobraBob said:
That's his canned response he has given once or twice before and on other sites as well. I think what everyone wants to know is if they experienced an issue with a car and if so, what was it?? :shrug:
I have a question about how our blowers are put together.Not the way Stiegemeier reassembles them after porting but the way they assemble them at the factory. I guess what I'm getting at is, are the snout and bearing housings doweled to the case from the factory or do they just bolt together without any line up dowels?
Thanks, Mark A
Thanks, Mark A
JKD COBRA said:
yup
2003 Silver
Banned
+1...that's what I was saying a few posts above.beenstruck said:
sedanman said:
While I think rotor RPM is more of a focus in this scenario, and the RPM vs. boost reference has already been made, you also have to consider that boost is just back pressure. Even though compression doesn't take place inside the case of a PD blower, that back pressure puts more force on the rotors when compressing the air downstream of the blower. That could also contribute to rotor deflection and case flex. I don't think these types of problems would be completely RPM-based. That might mean that a car producing less back pressure at a given RPM (i.e. LT headers, no cats, cams) might get away with a little more blower speed since it will be producing less boost at said given RPM.
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