T
TechHeavy
Guest
Here, here!Jerry Barnes said:
Like Mike said before me, I know have a thread to send friends with blower questions. Great information! You rock.
Some More Marauder Dyno Stuff...
- Thread starter Lidio
- Start date
Like Mike said before me, I know have a thread to send friends with blower questions. Great information! You rock.
M
MikesMerc
Guest
tmac1337 said:
Nope.
When the throttle is closed enough to create a vacuum in the intake (pretty much anything less than a half a pedal) the boost is "by-passed" internally within the eaton blower and the motor sees zero boost.
Opening up the throttle plate eliminates the intake vacuum, closes the by-pass, and only then intorduces boost to the motor.
Even better with the roots blower, its easy to modulate the boost and power your making. With 6 psi of boost on tap, you can deliver none, some, or all of it depending on how much you choose to give it.
There is absolutely nothing aggressive about the power unless you want it to be.
Furthermore, saying that you can have "too much power" down low is just silly in a 4500lb car. Unless you are giving up tons of TQ on the top end where the motor completely falls over (like a diesel motor does) there is absolutely no reason to not want the power down low. LOL....if traction is the issue, then just address the traction issue
Better yet, there is never a need to give it any more gas than you want to anyway. Like I said, the power is easily modulated with your foot. But, that's all moot anyway. With a 4500lb car, you need all the down low TQ you can get.sailsmen said:
As far as referring to "street" driving, that is exactly what is being referred to...street driving. That's actually the beauty of having the power down low. There is no need to rev the motor up to get the power. No need to break any speed limits. The "push in the back" torque feels great at low speeds and low rpms. Its the "big block" feeling. If you don't get that, well, I'm not gonna bother explaining
M
MikesMerc
Guest
Lidio said:
tallboy said:
LOL...yeah its time for me to retire from this thread. I'm sure there will still be a few more folks who are uncomfortable with the dyno results that will come along and try to put some kind of "spin" on it all. But, the results speak for themselves.
Time to split :burnout: :burnout:
maraudernkc
Supporting Vendor
Tmac
As always it comes down to Roots vs. Centrifical.
You need to factor in what you want and what you want to spend. There is alot of good information here on this site and I don't condone anyone who has a roots blower. If you have a MM at it's blown let's go have some fun:beer:
The roots blower is positive displacement blower and produces much more boost down low but also will have a higher diffirential tempature at the intake which means that you have to back out timming. The cooler the air comming into the motor the more timing you can run which=HPtmac1337 said:
As always it comes down to Roots vs. Centrifical.
You need to factor in what you want and what you want to spend. There is alot of good information here on this site and I don't condone anyone who has a roots blower. If you have a MM at it's blown let's go have some fun:beer:
maraudernkc said:
1. Was the car cold or at operating tempature?
....Totally warmed up, I always make sure they've been run and roled for a while before I begin to make pulls on the dyno.
2.Were you blowing a fan on it and if so how many HP fan?
....The fan in front of the car is a 36" barrel style fan, dont know the HP on it.
3. What was the tempature in the shop?
....The temp in the shop was about 60-65 degrees
4. Were you running the stock MAF?
....Yes the Trilogy's use the stock 80mm MAF and so did the Vortech MM too.
5. Were you running the stock Air filter?
....The Trilogy car used the totally stock air-box and factory filter element.
6. What octane fuel was run?
....Locally available 93 octane. No doubt winter blend this time of the year.
7. what fuel pump system were you running?
....Stock, in tank with Trilogy supplied Boost-a-pump.
8. Is there anything diffrent that is not included in the Roots blower kit on the car?
.... Absolutly nothing above and beyond the stock Trilogy kit.
9. What is your diffrential tempature at the intake under full boost using a Pyromoter?
....Sorry, havent checked that. Although with the '03 Cobra intercooler system included in the Trilogys I'm sure the inlet temps after the blower are only about 15-25 degrees above ambient which is what I see on Cobra's.
One thing I have to say is that this will be spun (as mentioned) into different directions because of differnt beliefs, philosophy’s and opinions. I don’t want this to turn into a ugly debate about the two most popular blower types for the Marauder’s. Just showing it like it is when it comes to low end grunt and the most used area of a MM torque range.
I’ve been installing centrifugal on the Mustangs for years. I was one of Vortech’s first direct dealers back in 1992. Dealer number 4 to be exact. When the 4.6L’s came along with their smaller cubes and less torque then we were used to in the Mustangs with 5.0’s…. We did well with the centrifugals, but they didn’t exactly fix what was wrong with these little 281 cubic inch motors. Low end torque or lack there of. The MM to me falls victim to this more then any thing for obvious reasons….. heavy.
I still love and push the Vortech’s in the Mustang scene and now though I also push the Kenne Bells too. These are screw type blowers, they make a lot of low end torque but don’t fall off in the high revs like the stock Eaton’s. Overwhelmingly the KB’s are liked better because of their instant gratification and low end torque. Whether it’s a stick or auto trans car. The only reason we don’t sell more of the KB’s is the end cost after buying the kit and paying install labor is much higher at this time.
The Trilogy kit does in no way makes to much, unmanageable TQ down low. It’s just right with the stock Torque converter and the stock 3.55 gears. And as some one already posted, if it spins the tires to much…. Fix the traction problem, not reduce the power or add less power!
Remember if this is some what of a dollar per performance comparison thing. Then it must be mentioned again that the Trilogy/Roots type blower in a MM performs very well in the real world with no other changes, only the blower kit. A centrifugal with a stock converter and non big gears in the axle has to “come on”.
I guess what I’ve delicately tried to say is that a centrifugal on a MM with no loose torque convter and tall axle gears will not feel the same or as good from street light to street light when horsing around. This is why my dynoing methods with the converter locked in 3rd and starting very low in the rpm’s is to show what you working with every day in a MM that’s mostly stock as far as other power train changes go.
I also want to say that both blowers add HP and TQ to a stock MM engine. Both blowers can lead to problems with a poor tune. But with proper tunes we’ve already had great dependability with Trilogy’s on lots of MM’s and I’ve had tons of Vortech equipped Mustangs with great long lasting results as well.
I’ve been installing centrifugal on the Mustangs for years. I was one of Vortech’s first direct dealers back in 1992. Dealer number 4 to be exact. When the 4.6L’s came along with their smaller cubes and less torque then we were used to in the Mustangs with 5.0’s…. We did well with the centrifugals, but they didn’t exactly fix what was wrong with these little 281 cubic inch motors. Low end torque or lack there of. The MM to me falls victim to this more then any thing for obvious reasons….. heavy.
I still love and push the Vortech’s in the Mustang scene and now though I also push the Kenne Bells too. These are screw type blowers, they make a lot of low end torque but don’t fall off in the high revs like the stock Eaton’s. Overwhelmingly the KB’s are liked better because of their instant gratification and low end torque. Whether it’s a stick or auto trans car. The only reason we don’t sell more of the KB’s is the end cost after buying the kit and paying install labor is much higher at this time.
The Trilogy kit does in no way makes to much, unmanageable TQ down low. It’s just right with the stock Torque converter and the stock 3.55 gears. And as some one already posted, if it spins the tires to much…. Fix the traction problem, not reduce the power or add less power!
Remember if this is some what of a dollar per performance comparison thing. Then it must be mentioned again that the Trilogy/Roots type blower in a MM performs very well in the real world with no other changes, only the blower kit. A centrifugal with a stock converter and non big gears in the axle has to “come on”.
I guess what I’ve delicately tried to say is that a centrifugal on a MM with no loose torque convter and tall axle gears will not feel the same or as good from street light to street light when horsing around. This is why my dynoing methods with the converter locked in 3rd and starting very low in the rpm’s is to show what you working with every day in a MM that’s mostly stock as far as other power train changes go.
I also want to say that both blowers add HP and TQ to a stock MM engine. Both blowers can lead to problems with a poor tune. But with proper tunes we’ve already had great dependability with Trilogy’s on lots of MM’s and I’ve had tons of Vortech equipped Mustangs with great long lasting results as well.
M
MI2QWK4U
Guest
Well said Lidio, I think you explained it better than anyone previously with your posts in this thread. Most folks dont know what kind of time and energy Lidio puts into these tests. He is absolutely meticulous, and pays a lot of attention to the smallest detains in an effort to be as fair as humanly possible. He really gets concerned when his findings may not set well with some, and draw fire, but what he produces are honest, well thought out results that are both factual and repeatable.
Lid, when things settle out with the new crib, KFC is on me! Good job on the detailed report.
Lid, when things settle out with the new crib, KFC is on me! Good job on the detailed report.
Smokie
New member
Lidio I have enjoyed your thread and the way you document everything you do. I feel compelled to come in defense of that little 281. How Ford chose to release the MM. does an injustice to that little 281, I changed the exhaust on mine (SVO shorties) the airbox (PHP) and U/D's....all else is what Ford put in it. I have 265 ft/lbs of torque at 2000 rpm's, arrive at 300 tq at 3850 and remain above 300 to 5200 rpm's.Lidio said:
If I stab the pedal from a dead stop the car will spin the tires without moving for about 1 to 2 seconds and gradually hook-up and start to bolt....I have; in my younger days owned or driven big block V-8's and with the exception of the 440 six-pack none of them bolted from a dead start any better than my little 281.
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Joe Walsh
STILL N/A
Lidio said:
I was just reviewing the boost curve that Lidio posted a few weeks ago and I have a question concerning the Centrifugal Superchargers......
The Centrifugal S/C boost curve rises with RPM and peaks at redline.
i.e. A 9 psi Centrifugal S/C does not make 9 psi boost until the very top of the rpm range.
Why can't you install a 14 psi Centrifugal S/C pulley and a bypass valve set at 9 psi?? That way you will get 9 psi boost much sooner in the rpm range and hold 9 psi until redline??
That's what all Turbocharger systems do....build boost to a preset limit, then the bypass/blow-off valve holds that level of boost until redline.
M
MikesMerc
Guest
There are a number of issues...
First, most by pass/blow off valve designs are meant for reducing huge back pressure (and the associated high reverse flow pressure on the impeller) that occurs when the throttle is closed....not regualting boost. Large levels of unreleived back pressure cause tremendous heat and can damage the blower at higher cfm levels when the throttle slams shut. Accordingly, most by pass and blow off valves are controlled by a vacuum line off the intake rather than by actually regulating boost pressure. When the throttle is closed enough to produce an intake vacuum, the vacuum line holds the by pass open and releives boost pressure.
Second, assuming you can find a pressure regulated valve, you'd have to make sure it is a by pass as the MM runs with a MAF. Once air is "sampled" by the meter it cannot be discharged into the atmoshpere. The draw back here is that the "by pass" is not as effective as a blow off valve as a by pass only recirculates the boost pressure (vs blowing it off into the atmosphere).
Third, you'd be grossly overspinning the blower at higher rpm ranges. Because a centrifugal blower makes power exponentially with higher rpms, the blower would spin right past its safe impeller rpm range before you ran it up much at all if you began with 9psi of effective boost at lower rpms. All the "rush" of boost that comes on that way is fun, there is a limit as how to apply it.
Last, you'd be making serious heat with a blower along with overspinning it if lower rpms produced boost. Again, the exponential boost relation to impeller rpm is the killer.
First, most by pass/blow off valve designs are meant for reducing huge back pressure (and the associated high reverse flow pressure on the impeller) that occurs when the throttle is closed....not regualting boost. Large levels of unreleived back pressure cause tremendous heat and can damage the blower at higher cfm levels when the throttle slams shut. Accordingly, most by pass and blow off valves are controlled by a vacuum line off the intake rather than by actually regulating boost pressure. When the throttle is closed enough to produce an intake vacuum, the vacuum line holds the by pass open and releives boost pressure.
Second, assuming you can find a pressure regulated valve, you'd have to make sure it is a by pass as the MM runs with a MAF. Once air is "sampled" by the meter it cannot be discharged into the atmoshpere. The draw back here is that the "by pass" is not as effective as a blow off valve as a by pass only recirculates the boost pressure (vs blowing it off into the atmosphere).
Third, you'd be grossly overspinning the blower at higher rpm ranges. Because a centrifugal blower makes power exponentially with higher rpms, the blower would spin right past its safe impeller rpm range before you ran it up much at all if you began with 9psi of effective boost at lower rpms. All the "rush" of boost that comes on that way is fun, there is a limit as how to apply it.
Last, you'd be making serious heat with a blower along with overspinning it if lower rpms produced boost. Again, the exponential boost relation to impeller rpm is the killer.
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martyo
MO derator
Call Dennis. He would be happy to TAKE your money.
clmrt
Just Thrilled
martyo
MO derator
***snicker***
Marauderjack
Senior Member
You guys are just plain MEAN!!
Subscribing to see where this might go.....(grin)!!
Subscribing to see where this might go.....(grin)!!