41/53dodges Posted September 19, 2013 Report Share Posted September 19, 2013 I'm back at school again, time to daydream about the truck while I'm gone! So I have a turbo from an old subaru laying around, I was wondering if anybody successfully made their flatty run a turbo? I saw one on youtube, 1950 plymouth I think? But the search feature here yielded little more than somebody on ebay trying to make an original carb into blow-through. I was almost thinking an industrial-style manifold with the bolt on exhaust flange up front and set up for an updraft carburetor would work nicely, if I could find one around here! the turbo could bolt straight to the manifold there and make the plumbing easy, just have to add a carburetor. So does anybody else have any suggestions/comments? -Josh Quote Link to comment Share on other sites More sharing options...
DJ194950 Posted September 19, 2013 Report Share Posted September 19, 2013 I like the IDEA for trying a small turbo but it needs several more parts. A waste gate for one, limits boost. Since this seems to be unk. speced turbo, it should be an adjustable gate with a boost gate to check it.. Ign. timing needs to be altered to work with the boost pressure as adjusted to get the most HP from the boost and at the same time prevent preignition.Best way my friend found to boost the air flow thru a regular carb. without continually blowing out the carb gaskets was to build a box that the carb sat into with sealed throttle shafts that protruded from the box to equalize the inner/outter pressure. This was not on a flat 6 and was many years ago.Mounting? A exhaust manifold from an industrial mopar flat motor of the correct size had som with exhaust exiting on the top side. A possibility IF you can locate one.Since you have some Extra time, look arround, send some emails to turbo specializing install co's with your questions. If you find some interesting, definative answers, I'm sure many on this forum would be at least interested! Doug Quote Link to comment Share on other sites More sharing options...
De Soto Frank Posted September 19, 2013 Report Share Posted September 19, 2013 (edited) Don't turbos work best on short-stroke / high RPM engines ? Cord, Auburn and Graham all featured supercharged engines back in the 1930's, and these were all L-heads... In the '50s, Studebaker, Ford, and Kaisers were available with the McCullogh / Paxton supercharger... the Kaiser used the Continental flat-head six... Edited September 19, 2013 by De Soto Frank Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted September 19, 2013 Author Report Share Posted September 19, 2013 Don't turbos work best on short-stroke / high RPM engines ? Cord, Auburn and Graham all featured supercharged engines back in the 1930's, and these were all L-heads... In the '50s, Studebaker, Ford, and Kaisers were available with the McCullogh / Paxton supercharger... the Kaiser used the Continental flat-head six... Depends on what you are trying to do. Gotta figure, every heavy diesel truck built since the 70's has a huge turbo diesel, with a torque curve much like ours. They make large amounts of torque due to the extra air, our little flatheads are no different. And besides, why not build it? A turbo is more efficient than a supercharger anyway, the only perk to a supercharger is no turbo lag. Quote Link to comment Share on other sites More sharing options...
greg g Posted September 19, 2013 Report Share Posted September 19, 2013 (edited) I would think a turbo sourced from one of those small diesel powered delivery trucks, Like Nissan, Mitsubishi, or those Mercedes, Freightliner Dodge Sprinters would be a good match for a flathead. There engines are in the same displacement neighborhood. They are designed to work at lower RPMs, these motors usually top out at about 3500 Rpms. So the turbos they use are designed to build boost in the 1500, to 3000 rpm range, they don't build a lot of pressure at about 7 to 9 lbs. and would work well in a suck through manner on a short runner intake with an SU or similar Carb. And would work well with the low compression ratio designed into our engines. You would probably need to find a pop off valve to keep pressure build in the 9 lbs max area to keep from buggering up bearings and other lower end internals. the other turbo advantage is no need to figure a way to power it, so no worries about belts, brackets, clutches etc. And turbos used to be rare but I would have to think used ones would be fairly common these days. This one looks pretty cobbed up, but seems to move under its own power. There is a comment regarding the stock carbs having a vented float bowl that makes the work i the blow through manner. The intake plumbing looks a bit residential waste pipe, but I guess it works. http://www.curbsideclassic.com/blog/car-show-classic/car-show-classic-home-blown-flathead-six-in-a-1949-plymouth-special-deluxe/ Edited September 19, 2013 by greg g Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted September 19, 2013 Report Share Posted September 19, 2013 Imagine how much more power he could have made if he used smoother hoses and turned the "Y" pipe around so that the front carb could recieve a smoother flow of air. And it sounds like he needs an overdrive to get the revs down like he wants. Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted September 19, 2013 Author Report Share Posted September 19, 2013 I would think a turbo sourced from one of those small diesel powered delivery trucks, Like Nissan, Mitsubishi, or those Mercedes, Freightliner Dodge Sprinters would be a good match for a flathead. There engines are in the same displacement neighborhood. They are designed to work at lower RPMs, these motors usually top out at about 3500 Rpms. So the turbos they use are designed to build boost in the 1500, to 3000 rpm range, they don't build a lot of pressure at about 7 to 9 lbs. and would work well in a suck through manner on a short runner intake with an SU or similar Carb. And would work well with the low compression ratio designed into our engines. You would probably need to find a pop off valve to keep pressure build in the 9 lbs max area to keep from buggering up bearings and other lower end internals. the other turbo advantage is no need to figure a way to power it, so no worries about belts, brackets, clutches etc. And turbos used to be rare but I would have to think used ones would be fairly common these days. This one looks pretty cobbed up, but seems to move under its own power. There is a comment regarding the stock carbs having a vented float bowl that makes the work i the blow through manner. The intake plumbing looks a bit residential waste pipe, but I guess it works. http://www.curbsideclassic.com/blog/car-show-classic/car-show-classic-home-blown-flathead-six-in-a-1949-plymouth-special-deluxe/ That is interesting, I would have never figured these carbs would be at all effective. Expecially with the accelerator pump situation. Wonder how well that actually works? Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted September 21, 2013 Author Report Share Posted September 21, 2013 Okay, I have obtained a pair of holley 1904 visi-bowls, now those may be a step in the right direction if I can do a blow-through design. Or do a draw through and use a more tune-able carb Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted January 15, 2014 Author Report Share Posted January 15, 2014 Gentlemen 1 Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted January 15, 2014 Report Share Posted January 15, 2014 Where does the float bowl vent on these carbs? If it vents into the air inlet area it may work, as long as it doesn't leak too bad externally. You need to have that pressure difference between the throat of the venturi and the "atmospheric" pressure in the float bowl for gas to flow through the jets. If it vents to atmosphere then I would expect the venturi pressure may be equal to, or higher than atmosphere and you won't get any gas into the mix. I'll be interested to see the outcome. Merle Quote Link to comment Share on other sites More sharing options...
austinsailor Posted January 15, 2014 Report Share Posted January 15, 2014 (edited) Gotta figure, every heavy diesel truck built since the 70's has a huge turbo diesel, with a torque curve much like ours.Just a minor thing, has nothing to do with what he's trying to do, but not all newer trucks have turbos. I bought a 1987 international dump truck recently to use around my place. Darn thing has 900 cubes of old fashioned non turbo diesel power. Better for my use, no turbo to worry about caring for. But - not all are turbo powered.I sure would like to see a flathead powered with one, though! Gene Edited January 15, 2014 by austinsailor Quote Link to comment Share on other sites More sharing options...
Dave72dt Posted January 15, 2014 Report Share Posted January 15, 2014 I'll assume that Subaru turbo picture is an install in progress. If it isn't the turbo is short lived without the oil pressure feed line to the center of the turbo. Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted January 15, 2014 Author Report Share Posted January 15, 2014 I ran the thing a bit earlier just to see what would happen. Aside from a bunch of oil leaks, it works great! Turbo comes online about 1200-1500 and I can feel the engine breathing better. Since that photo ive added all the hoses, and thats a mess! If nothing else, the thing sounds awesome with the exhaust right off the turbo. Gotta go tune it up and chase the leaks, il post a status report later! And interesting info Gene, I've never seen a newer truck without it! Learn something new every day! -Josh Quote Link to comment Share on other sites More sharing options...
austinsailor Posted January 15, 2014 Report Share Posted January 15, 2014 Actually, I typed before thinking. It's really 9 liters, which is about 550 cubes. Still a little bit of displacement. Strange thing is, it seems to have about the same power as my previous dump truck which had a 427 gas V8. I lost the transmission in the older one - really. Bell housing shattered with a big load on and the tranny disappeared through the floor! Ok, enough distractions - let's hear more about the turbo flathead. Gene Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted January 15, 2014 Author Report Share Posted January 15, 2014 Still an impressive engine Gene! I took the truck out a few minutes ago, wot at 2500 rpm yields 4-5 psi and a blown out oil return! As wilee coyotee would say, back to the ol' drawing board! Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted January 15, 2014 Report Share Posted January 15, 2014 Just a minor thing, has nothing to do with what he's trying to do, but not all newer trucks have turbos. I bought a 1987 international dump truck recently to use around my place. Darn thing has 900 cubes of old fashioned non turbo diesel power. Better for my use, no turbo to worry about caring for. But - not all are turbo powered. I sure would like to see a flathead powered with one, though! Gene In the 80's naturally aspirated engines were still fairly common. By the mid 90's, when emission regulations started to kick in on diesel engines, we started seeing more turbocharged engines. Now it's hard to find a diesel that isn't turbocharged with some sort of variable geometry turbo to aid in EGR and other emission system functions. Merle Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted January 15, 2014 Report Share Posted January 15, 2014 (edited) Still an impressive engine Gene! I took the truck out a few minutes ago, wot at 2500 rpm yields 4-5 psi and a blown out oil return! As wilee coyotee would say, back to the ol' drawing board! 2500 RPM @ WOT? Something wrong there. Should get over 3500, especially with no, or low, load. 4-5 psi of boost isn't much, but probably enough for these engines. Maybe I'm just used to modern diesel engines running 20-30 psi of boost pressure. Merle Edited January 15, 2014 by Merle Coggins Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted January 15, 2014 Author Report Share Posted January 15, 2014 2500 RPM @ WOT? Something wrong there. Should get over 3500, especially with no, or low, load. 4-5 psi of boost isn't much, but probably enough for these engines. Maybe I'm just used to modern diesel engines running 20-30 psi of boost pressure. Merle well considering i opened it up in a 1/4 mile stretch before the roundabout and thats what i got when the line blew id say thats about right. now given a good place to let it wind up more i darn well know it will do it! Quote Link to comment Share on other sites More sharing options...
Dave72dt Posted January 15, 2014 Report Share Posted January 15, 2014 What did you do to enrich the fuel since the added air would make it run lean? Is there a waste gate on the turbo? why did it blow an oil return line? That's a no pressure line to sump. Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted January 15, 2014 Author Report Share Posted January 15, 2014 the oil return line was my own fault, bad design that broke from heat. didn't touch the carburetor as of yet, and the turbo has a pressure controlled gate at about 7psi Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted January 15, 2014 Author Report Share Posted January 15, 2014 After some repairs and cleaning up the oily mess, I made another test run. I will say the waste gate scared the crap outta me when it hung open once, thought I had broken something! It works really nice, still needs some tuning but it makes a really noticeable difference. I guess time will tell if it works! Quote Link to comment Share on other sites More sharing options...
DJ194950 Posted January 15, 2014 Report Share Posted January 15, 2014 Glad to see some on this forum actually give the turbo at test drive! Has been talked about on the car and the truck side for quite some time. Plan for an air cleaner? Sure you'll needed to up size the main jets. Maybe change the advance curve on dist. also to get the most from your setup. If much more boost the carb may need to put in a metal box to add the boost into to equalize the inside/outside pressures on the carb to prevent carb gasket blow outs. But that is a real pain according to a friend, as the throttle shaft, choke cable , vac. advance line still need to be connected through the box. His motor was a 340 mopar w/ belt driven supercharger and blowthru 4 bbl. carb. But I totally appreciate your efforts and posts! Doug Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted January 15, 2014 Author Report Share Posted January 15, 2014 The air cleaner I havent figured out yet. Sadly I think the oil bath will probably have to hit the road in favor of one of the slip on universal jobs... Quote Link to comment Share on other sites More sharing options...
DJ194950 Posted January 16, 2014 Report Share Posted January 16, 2014 How sweet it would be to somehow use an original oil bath oil cleaner mounted somewhere under the hood, but I'd totally iunderstand using something else, just get 'er going! I'm rooting for you! Doug 1 Quote Link to comment Share on other sites More sharing options...
41/53dodges Posted January 16, 2014 Author Report Share Posted January 16, 2014 Now if I could find a truck style one that mounted on the inner fender, that would be cool. But in the meantime I have a turbo that blows oil to deal with first! Quote Link to comment Share on other sites More sharing options...
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