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Mercury's Turbo Engines

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Old 12-20-2009, 02:06 PM
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Originally Posted by H2Xmark View Post
on a old style setup you will have lag, but on a modern setup when you back off the throttle the turbo DOES NOT slow down, so when you add throttle the turbo boost is there due to the bypass valve, on the old style they used a pop off valve and the boost dumped into the air, lost power ect.
Actually I think you mean dont slow down- AS MUCH

Its gotten really good but not quite instant. Its close though.

I got a ride on a Brummett (sp I think that was the builder) turbo Schiada this summer and it was breathtaking.

UD
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Old 12-20-2009, 03:03 PM
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Actually I think you mean dont slow down- AS MUCH

Its gotten really good but not quite instant. Its close though.

I got a ride on a Brummett (sp I think that was the builder) turbo Schiada this summer and it was breathtaking.

UD
you are right, if the throttle is held closed for a long period of time the boost will drop, i dont know of any boat engine builders using variable vane turbos like on the car scene. i know leon derebery is builing some real trick turbo motors that i think a lot of builders would love to see
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Old 12-20-2009, 03:36 PM
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Here are two short links of the dyno pull at 1,800 rpms.
The first one is just a quick flash from the engine over to the scale.
http://www.youtube.com/watch?v=ciU3a_Ulh1k



Second one is focused on the scale and the TACH to the upper right and you can see the torque made with
very little rpms / boost.

This was done with the waste gates set up at 7 LBS for tuning
and as you can see with the attached picture that is not
where the boost is finally run at.

http://www.youtube.com/watch?v=5ZEHb...eature=channel


Enjoy
Jon
Attached Thumbnails
Mercury's Turbo Engines-pa310196.jpg   Mercury's Turbo Engines-pa310197.jpg   Mercury's Turbo Engines-check300-5.jpg  

Mercury's Turbo Engines-check300-7.jpg   Mercury's Turbo Engines-check300-3.jpg  

Last edited by cougarman; 12-20-2009 at 04:51 PM.
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Old 12-20-2009, 03:46 PM
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Originally Posted by Whipple Charged View Post
Wow thats a pretty arrogant statement!

Do you know how much a quad turbo engine is gonna cost from Merc? How about from an engine builder?

So turbos now reach full boost at 1700rpm? Or start to reach boost, meaning 1psi over barometric psi? Because 1psi and 15psi are pretty different power curves.

So your saying identical engines, identical intercoolers, identical air fuel, timing and boost and the turbo will out accelerate a twin-screw? Sorry, thats extremelly incorrect.

Turbo's make great HP because they take very little power to operate, but because they are dependent on exhaust flow, they can never equal throttle response in identical situations to an efficient positive displacement supercharger unless you introduce NOS or some other type of additive to get the turbo's to spool up quicker.

That does not mean they won't work, and that doesn't mean they have the lag of the old days, but turbos react off the engine, where a SC reacts off the throttle blades opening. No matter what, with today's technology, you can't get passed that. Its physics, can't defy those laws very often. Now what one refers to as lag may be different than the next. I drive a turbo diesel nearly every day, its got horrible lag, just awful, and thats with a lot of the new technology, and I've certainly tinkered with it plenty. When I get in our supercharged suburban, they're is zero comparison. If you say hey its got 1 psi at the hit of throttle and 1 second later, its 5psi, thats still "lag" when compared to a PD twin-screw. It may not be the lag of a single turbo, or a bad turbo system where you can count 1 missisipi, 2 missisipi before you finally get boost type lag, but in comparison, if you have less boost in an equal test, then thats lag.

Turbo's are extremely expensive and very complexed when done right. They're a packaging nightmare in many applications and with all the water jacketed headers absorbing such high heat from the high back psi and psi from the boosted side of the turbo, exhaust tend to go through more duty cycles than that of a PD supercharger. So turbo's are not free hp because they create tremendous back psi in the exhaust, this creates a lot of heat and that hot air is pushing the turbo impellers and it transfers that heat to the air charge exiting the turbos. But they're not dragging on the crankshaft so they'll almost always make more peak HP then positive displacement superchargers. Turbo's also can have small torque ranges, espeically with high HP engines which turn higher than average RPM, which is why you'll see Merc have 4 turbos, 2 small, 2 big, that helps the response time and helps give a better useable rpm range. Remember, what we all can do with custom built engines, Mercury has to "package" and warranty so it gets far more complexed. I think many will also be shocked to see what type of motor these are actually being installed on.

Last, turbo's in the automotive field are having major issues because they have a very negative effect on cold-start emissions, which is one of the biggest polluters of the cars today, before the cat's are lit off. This has posed a huge issue for turbo mfg' not to mention the fact that they can't get rid of the lag and the OE's target power numbers and OE's target price ranges. Many, such as Audi, VW, etc. have left turbos and went to PD style superchargers because OE's can't run 20psi of boost in most applications, so at 8-12psi, there is very little power differences, but there are huge torque differences.

So overall, turbo's are not gonna take over the world, they've been here and will continue, but they have some issues, just like all other power adders, and therefore they're will be customers who like one over another. Whether its useable rpm ranges, noise, peak hp or low end torque, price, packaging or whatever, there's a place for all of them.

Dustin,

Thanks for taking the time to add all this information as we all enjoy the continued education in the Horse power world.

Few notes though, I didn't say turbo's reach full boost by 1,700 rpms. I believe I said they start to build at 1,650 and are alive and well by 1,700.

Also I didn't say Blowers would vanish, I didn't say turbo's will take over the world. I believe I said I think you will see a slow switch over.

Bottom line is every one has there likes. Some like carbs, some like fuel injection, some like blowers some like turbo's.
Some just like the look of a blower and could care less if it's short lived , long lived etc.

So if nothing less people can learn more and more where turbo's are progressing.

Thanks
Jon
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Old 12-20-2009, 03:48 PM
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So I guess no one has info on the engines being introduced in Feb in Miami.

Looks like we got off task,.......but I can tell you we like Turbo's

Mercury's normally pretty Quite,......so my guess is not pictures until they unvail them to the public.



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Old 12-20-2009, 04:48 PM
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Probly a v8 turbo diesel. My guess...........
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Old 12-20-2009, 05:11 PM
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Cougarman,

I'm a big fan of turbos not against any of this, yet I ask a question and no one answers, so be it.

What makes the engine you keep showing pics of so special? It has pop off valves on the intake side and waste gates on the exhaust side, where is all the special stuff that makes this better or different or is it just a good powerful engine?

It appears to be "just" another engine with smaller turbos to spool up quick and waste gates to dump off excessive exhaust pressure?

I read this whole thread and just don't see any concrete answers as to why "today's' turbocharged engines will solve all the bottom-end problems and all the problems assoicated with throttleing a boat.

I know in the auto world there is high tech turbo charged engines that have great acceleration and all kinds of things to keep turbos spooled up, just don't see it here unless I'm missing something?

One more question, why doesn't a turboed nitro funny car come close to beating a supercharged funny car if the acceleration of both types of engines can be close to equal as is implied on here?

Last edited by HabanaJoe; 12-20-2009 at 05:26 PM.
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Old 12-20-2009, 05:25 PM
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Cougarman,

I'm a big fan of turbos not against any of this, yet i ask a question and no one answers, so be it.

What makes the engine you keep showing pics of so special? It has pop off valves on the intake side and waste gates on the exhaust side, where is all the special stuff that makes this better or different?

It appears to be "just" another engine with smaller turbos to spool up quick and waste gates to dump off excessive exhaust pressure?

I read this whole thread and just don't see any concrete answers as to why "today's' turbocharged engines will solve all the bottom-end problems and all the problems assoicated with throttleing a boat.

I know in the auto world there is high tech turbo charged engines that have great acceleration and all kinds of things to keep turbos spooled up, just don't see it here unless I'm missing something?

One more question, why doesn't a turboed nitro funny car come close to beating a supercharged funny car if the acceleration of both types of engines can be close to equal as is implied on here?

HabanaJoe,

Cause it works, it's not always what you see, but rather what you don't see that makes it perform as it does.

Thanks
Jon
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Old 12-20-2009, 05:41 PM
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Probly a v8 turbo diesel. My guess...........
I heard ilmor is debuting a new high HP forced induction engine.......

Pretty exciting...

UD
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Old 12-20-2009, 06:01 PM
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Ok, so you don't why it's different just that it works as you say it does, I guess I'll have to take that then - LOL!
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