Turbo

[DuckRyder]

If turbulance is what you are after you might take a look at this:

http://www.metricmechanic.com/catalog/s ... ulance.php

It appears that they removed the photographs, but the concept could certainly be applied to any engine.

(His engines do work, if anyone has a BMW)

[Fordnatic]

Maybe the cool down is a wives tail, but it does have some merit in some applications. I flew Piper Navajos with 350HP Lycoming turbocharged/injected engines, and the rule was to idle for a minimum of 3 minutes prior to shutdown. Most pilots did this without question, and the turbo's would normally last until TBO (time before overhaul) was used up for the engines (2200 Hrs). But...we started having a rash of turbo failures. It's exciting on take off when you lose half the power on one engine, the asymmetrical thrust makes things get exciting real quick. When disassembled, they were found to be coked up. We discovered just one of the pilots was ignoring the 3 minute rule and just shutting down when he wanted. Needless to say he was let go and "presto" no more turbo problems!

[averagef250]

this may be a dumb question but. it occurs to me turbos were being used on gasoline engines in the 80s infact Buick had the 1980 Buick Regal limited 3.8L Turbo that ran a Rochester and a Turbo. it came factory equiped like this,I know because I owned one. then theres the Ford Thunder bird Turbo Coupe that ran a 2.3L with a turbo charger it was fuel injected but still a gasoline burning engine. and also the earlier Ford Mustang SVO ran a turbo charged 2.3L Aswell....Turbos to my knowledge were used on gasoline engines way before diesel in automotive applications (not Big Rigs) as far back as I can remember my understanding of it is A. lower compressions ideal 8.0:1-9.0:1 max compression. B. you have to strengthen up the bottem end to withstand the added strain the turbo puts on it. C. you need adequate fuel for the increased air intake so you don't go lean. D. an Inter cooler helps alot on the intake charge temp and boosts power due to the cooler more condensed charge. So why the general attitude turbos were/are designed for diesels when infact they were installed on gas engines then adapted to diesels one of the first of which was the Ford 7.3L Turbo Diesel

Both gas and diesel engines have had turbos.

The point I was making is that diesels like turbocharging, gas engines do not. Maybe better phrasing is diesels are more conducive to it. Diesels do not have an air/fuel ratio to concern about or any sort of spark timing.

The 7.3 diesel was one of the last light duty pickup diesels to see turbocharging first seeing a turbo in 1993. The IDI was an antique when it was put into ford trucks in 83 and even when Binder designed it in the mid 70's. The IDI is a horridly innefficient, heavy, very high revving excuse for a diesel. Before the IDI, Binder already had the DT360, 466, 570, etc. These are great, well designed direct inject diesels with real medium duty components and a fuel system worth a salt. If Ford wasn't V8 retarded like the rest of america they would have worked to fit the DT360 or a scaled down version of it into the pickups. The IDI is great for burning crap fuel that other diesels don't burn and as a boat anchor. (I have a 7.3 N/A F350 and hate the engine, it's modded/tuned and struggles to move the 11K pound truck empty with low gears, forget towing, and gets between 7 and 10 MPG)

If you want quiet and virtually no diesel smell a commonrail swap like anything '03+ Cummins will do it. 600 lb/ft off idle is stock power and 35K PSI multiple event injection makes for a very smooth, quiet engine for a diesel.


I still think a turbo gas engine is a bad idea for towing. The FE's have a pretty nice combustion chamber. They have plenty of squish with the only drawback being poor valve design, but with a turbo intake flow isn't very important.

[FreakysFords]

Maybe the cool down is a wives tail, but it does have some merit in some applications. I flew Piper Navajos with 350HP Lycoming turbocharged/injected engines, and the rule was to idle for a minimum of 3 minutes prior to shutdown. Most pilots did this without question, and the turbo's would normally last until TBO (time before overhaul) was used up for the engines (2200 Hrs). But...we started having a rash of turbo failures. It's exciting on take off when you lose half the power on one engine, the asymmetrical thrust makes things get exciting real quick. When disassembled, they were found to be coked up. We discovered just one of the pilots was ignoring the 3 minute rule and just shutting down when he wanted. Needless to say he was let go and "presto" no more turbo problems!

looks like we both learned that lesson by similar means. In our case it was ag trucks. Helo'd one into the ground trying to make a rolling bank on a field several years back. Achieved nose up and poof, no power. Nearly full tank of spray, ripped the dump valve and made it over the pwr lines only to flat stall right back to the green side. Got stuck back in a Pawnee for the rest of the season. Fun to fly, but sucked having to sit back down for reloads 4 times as often.

[averagef250]

I have seen diesel turbos with lots of miles that had coked oil inside, but it really wasn't a large buildup. For the most part though, the coked oil I find is under the turbine wheel behind the thin sheetmetal barrier that protects the sealing ring. The oil that makes it past the ring cokes behind that barrier.

Maybe diesel turbos operate cooler if you're guys coking experience seams to relate to gas engine turbos? What do gas engine turbos see for EGT? My four is maxed at 1300F pre-turbo so the turbo is likely a couple hundred less. On oil cooled turbos it might have something to do with the oil flow present in diesels. There's 60-80 PSI going into these cummins turbo at cruise speed.

[shaggys_bump]

I would start out really mild and go with one large turbo pushing low boost,
you will be really surprised at how much 7 #'s will do.

[Happy_Camper]

7 #s based on a great flowing engine... Yeah, I'm good with that!
That's pretty close to what the centrifugal supercharger pushes on my 302 sbf. Runs pretty strong.
7#s is almost 1/2 atmosphere, so on a 300HP build, that would be about 400-420HP, right where it's needed. The key is "good flowing". I'll be interested to see what the guys at Survival have to say.

I've just started looking at the new technology in turbocharging, and it's pretty amazing! I think it would be a lot of fun, as long as someone else has all ready been there.

[rjewkes]

What about just blower motoring it? What poundage does that give you?

[Happy_Camper]

Blowers like a Roots style, or twin screw, build boost right off idle. If you want a tire smoking stump pulling monster of an engine, they are awesome!
Boost pressure is determined based on the drive:driven ratio of the supercharger, and also restriction to airflow from the supercharger, intake,heads,cam,exhaust, etc.

I really don't want to see boost below about 2,500 rpm. So either centrifugal supercharger, or a more efficient turbo setup would be the better way to go in my case... if it's even possible.
Towing is a different animal than anything I've built for before. And I have basically no BBF hands on experience. It's really long WOT pulls through mountains, where heat is built not only by the engine, but the transmission as well. In a normal car or even a track car, EGR can be used during part throttle to cool the combustion chamber back down between the short pulls. Mixtures can be richened to assist in cooling the combustion chambers, but (IMO) that's a pretty poor way to do things. Like the diesels you see that just poor black smoke out the exhaust under heavy load. That is not something I want to be part of. Anything below about 12.5:1 AFR on a gas engine, and the people stuck behind it are gagging.
It will be interesting to see what the gurus at Survival FE have to say. Or maybe someone will build a turbo gas rig. I've still got plenty of time before I can even start on this.

[averagef250]

If you have black smoke from a turbodiesel you are overfueling. Setup properly turbodiesels do not smoke more than a light haze and puff during shifts/turbo spool.

[bntyhntr00]

I love turboed gas motors!! <let me just start with that lil bit of turretts syndrome bliss> I have done a few of them and if done right they are outstanding!! to repeat some of what I have read so far ---- look into injection!!! you will be much happier (broke but happy) -- other than that keep doing exactly what you're doing - research the hell out of it and realize that a great deal of what you will hear is parroting of bad, misinformed, personal opinion. There are some extremely knowledgable folks on this site that seem to always provide great guidance. I wont offer any advice because I have a too many issues to list and still consider 500HP to be a viable daily driver. But with a turbo'd vehicle I think that set up correctly a 1000HP is still a great daily driver. And now I will shut up because I'm too excited to continue.......................hahahahaha