Slant Six Forum
https://slantsix.org/forum/

New Slant EFI intake....
https://slantsix.org/forum/viewtopic.php?t=53276		 Page 7 of 11
Author:  CNC-Dude [ Tue Jul 22, 2014 5:04 pm ]
Post subject: 
Quote:
Any prototyped working units yet? Are you 3d printing for casting or prototyping..and are you running cfd simulation..theres alot left in plenum design to equalize pressure and flows into the runners by using a double plenum(cone over plenum) as well as a plenum shaped much like a open wheel cars intake "scoop" above the drivers head..why skimp out on a rectangular plenum..look at the plenum on a skunk 2 k20 honda manifold..that is an almost ideal plenum arrangement. I am also building a few intakes as well..both fabricated sheetmetal units as well as some lost foam castings..ive got my own ideas however based on many years in the "import game"...ive been around my fair share of 500+hp 1.8L 's..all of which carrys over to slants readily. With respect..i like seeing new product offerings for such an old design..keep at it. Your renderings are nice.
A sheetmetal prototype is in the works right now, just have a full plate with many other product development projects for other brands going on as well as my own proprietary product line. The finished product will be cast aluminum in my foundry, so after the sheetmetal prototype is tested and approved for production, then I will make the patterns and cores for casting.

The sample intake I posted a few months ago was just eye candy and not an actually representation of what my intake was going to look like, but yes a full flow simulation as well as a "real" flowbench analysis will be performed to evaluate and eliminate any issues that are present.
Author:  dwrlhcaz [ Tue Jul 22, 2014 5:12 pm ]
Post subject: 
Excellent! Stay vigilant! Look forward to seeing the end results! Lots room for improvement on these engines in my opinion. Bring them into the modern age a bit.!
Author:  pishta [ Tue Jul 22, 2014 5:58 pm ]
Post subject: 
Quote:
Here is a thought- instead of a complete new manifold, why not a series of spacers that go between the head and the intake manifold that hold the injector bungs? Then the stock intake manifold could be used with an adapter for the throttle body. The stock exhaust manfild couldn't be used, but you wouldn't want one for a fuel injected application anyway. Londer manifold studs would be required, but that is pretty easy to accomplish.
Just make them bossed on both sides and double ended so you only have one casting to make/buy. You could drill them for intake injectors or tap them for exhaust O2 or thermocouples or just closed for normal exhaust, but with a better flow path! The double ends could be flipped to match what the original lugs were clocked as. Buy 12 and do the entire head with supporting longer studs ad i think ypu would want to run a nut to the head side and a nut on the manifold side too. There is my $5 doller idea...:-)
Author:  dwrlhcaz [ Tue Jul 22, 2014 9:26 pm ]
Post subject: 
Here's a good read...still ALWAYS boils down to R&D...
http://forums.hybridz.org/topic/61549-t ... num/page-2
Author:  Dart270 [ Wed Jul 23, 2014 6:03 am ]
Post subject: 
OK, Triumph TB/injectors (I asked in other thread). 44 mm should be a very nice size.

Lou
Author:  pishta [ Wed Jul 23, 2014 8:40 am ]
Post subject: 
Quote:
Quote:
Here is a thought- instead of a complete new manifold, why not a series of spacers that go between the head and the intake manifold that hold the injector bungs? Then the stock intake manifold could be used with an adapter for the throttle body. The stock exhaust manfild couldn't be used, but you wouldn't want one for a fuel injected application anyway. Londer manifold studs would be required, but that is pretty easy to accomplish.
Just make them bossed on both sides and double ended so you only have one casting to make/buy. You could drill them for intake injectors or tap them for exhaust O2 or thermocouples or just closed for normal exhaust, but with a better flow path! The double ends could be flipped to match what the original lugs were clocked as. Buy 12 and do the entire head with supporting longer studs ad i think ypu would want to run a nut to the head side and a nut on the manifold side too. There is my $5 doller idea...:-)
Image

flip universal casting around boss up until it fits your intake side, then flip exhasut over boss down so you dont see it. Youll have to drill EFI holes in boss. I think AL would hold up.
Author:  Tim Keith [ Sat Jul 26, 2014 12:05 am ]
Post subject: 
One question that I have about a port injected intake manifold on a daily driver slant six, is whether the injectors are affected by the heat from being so near the exhaust? If so, then it might be good to add extra metal around the injectors to aid in cooling, but heat might not be a factor.
Author:  ntsqd [ Sat Jul 26, 2014 6:18 am ]
Post subject: 
Nissan L-series engines are non cross-flow designs as well. I've not heard of their injectors having abnormal issues due to the exhaust being nearby.
The fuel flow thru the injectors will have some cooling effect, and the atomization of the fuel at the injector's nozzle will tend to cool immediate area as this is exactly how A/C - Refrigeration works. The pressure drop isn't as great, so the effect will be less but it's there.
Author:  Dart270 [ Sat Jul 26, 2014 8:52 am ]
Post subject: 
Yes, heat is a factor, almost certainly.

I have a hot starting lean out issue and I believe Sam has had the same thing. I am convinced it is the injectors heat soaking when you shut it off, before they can cool off. I think some are hotter than others. Have not tried to fix this yet, but I know how to start the car and keep it running now.

I plan to locate my injectors a bit further back from the head (1.5-2.5" back) on my next port EFI intake.

Lou
Author:  Tim Keith [ Sat Jul 26, 2014 11:37 am ]
Post subject: 
Quote:
Nissan L-series engines are non cross-flow designs as well. I've not heard of their injectors having abnormal issues due to the exhaust being nearby.
The L-series intake ports are raised above the exhaust, more than two inches. There a larger water core around the intake ports, and the head is aluminum.

http://dimequarterly.blogspot.com/2012/ ... -head.html
Author:  oldskoolracer [ Sat Jul 26, 2014 12:18 pm ]
Post subject: 
The L-Series also had a pretty elaborate fuel rail too, had a couple loops in it Im assuming helped keep the fuel in the rail cooler...

Unfortunately the big killer with the slant is the intake and exhaust runners bolt to the head side to side instead of above and below like the L-series engines... Definately builds some excessive heat where the manifolds meet the head.

One possibility would be a composite manifold? Would be expensive Im sure, but good for insulation. Or even try to fabricate phenolic injector bosses into the manifold to insulate the injectors that way...? Im not a designer or fabricator by any means, but ideas still run through my head so why not spurt em out huh? :lol:
Author:  pishta [ Sat Jul 26, 2014 1:23 pm ]
Post subject: 
Seems the heat soak issue with the injectors has to do with the increased resistance the copper coils experience when hot. It can decrease injector duty cycle by as much as 1ms. On a 2.2ms pulse at idle, that is huge. Divorce the intake from the exhaust would be best bet or Run headers or true Dutra duals. Maybe a heat shield between every runner or maybe easiest, cool your fuel (or freas air intake) . Run it through a P/S cooler and cycle ignition 3 times before hot start. You guys running AL or cast iron intakes?
Author:  CNC-Dude [ Sat Jul 26, 2014 3:21 pm ]
Post subject: 
Cast iron is probably the worst material to use for an intake when also using sensitive electronics. Remember the houses back in the 40's and 50's that had radiators for heating. They only used hot water to heat a room with because the cast iron holds heat. Aluminum dissipates heat and doesn't create issues like that with electronics in close proximity to them like injectors. So you might not be able to eliminate the heat soak problem if using a cast iron intake converted to EFI. Maybe a heat shield for the exhaust may help some.
Author:  Tim Keith [ Sat Jul 26, 2014 7:51 pm ]
Post subject: 
Quote:
The L-Series also had a pretty elaborate fuel rail too, had a couple loops in it Im assuming helped keep the fuel in the rail cooler...
If there was ever a custom slant six head adaptations along the lines of the L-series might be good. The closed chamber "peanut" chambers might be good, but might have 12:1 static CR on a 225. The raised intake head might accept OEM style slant six and exhaust, but that would require the gasket surface for the valve cover to be raised too. The Nissan head could have been push rod operated. The L-series did not make a lot of power unless it was rev'd to 8,000 RPM, the turbo helped with lower speed torque. Nissan used all sorts of cylinder head designs on the L-series, some with huge ports. A 150 hp na L20B four is getting on the ragged edge, but carbed stock these 2 liter motors did better than the stock Mopar 2.5 did with EFI, considering that the Nissan motor was out of production by then. The custom head thread is never dead :)
Author:  Dart270 [ Sun Jul 27, 2014 10:16 am ]
Post subject: 
Sam and I are using offy alum intakes with our EFI systems with welded in injector bungs. Not enough. I agree with Pishta that it is likely changes in the injector solenoid performance at low pulse width with heat/overheat.

Thanks for the info and thoughts, everyone!

Lou
Page 7 of 11 All times are UTC-08:00
Powered by phpBB® Forum Software © phpBB Limited
https://www.phpbb.com/