I am building a bit of an oddball, looking for some feedback from you experts. the build is a gen 1 small block chevy, it's a 4.125 bore Rodeck aluminum block, i am destroking it to 377 cid, heads are 18 degree Bowtie nascar heads. since there is only single 4 intakes for these heads, i am building my own. i am using a shearer LS water to air intercooler between the intake and the upper plenum, two 75 mm mustang throttle bodies,, 2 borg warner S300SX-E 73 mm turbos. Holly dominator EFI, Coil on plug ignition. so have a look at my design and let me know what you think, good or bad.

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There is some very nice design work there and very easy to visualize what you are trying to do.

My first thought: You have two injectors per runner and in order for the injectors to get fuel of the proper amount
the Injector Fuel rails would have to be a large diameter.
The other issue is that the fuel would be either traveling from left to right or right to left and the end injectors might get "shorted" by the length of the rails and the 7 other injectors disturbing the flow of the last injector.

My thought because you already are planning to have a integral Inter-cooler on top, would be to have two sets of rails and the injectors on two levels (one set about an inch higher vs the other set.) Lots of pictures out there on that design.

I will reply to other parts of the design but with just do one point at a time.

Overall you have some very nice design work there. Assume it is all your work.

Tom Vaught

 

I am using Kinsler 1in id fuel Rail and using -10 line, and feeding each rail with 2 seperate weldon pumps or that dual siameased Holley pump, didn't really think about the front to back supply potential issue, Maybe i split each rail in the middle and have Rails, 2 feed lines and 2 return lines on each side, 4 injectors per rail. i was going to use one 80lbh and one 140lbh in each port, only using the bigger one under high load, the issue is the width of the intercooler designed for LS which has a wider space between the intake flanges, I have already tipped the fuel rail/injector out ward 5 degrees, and also have to use the small diameter injectors because of space or lack there of, and raise the fuel rail with extensions to clear the water fittings of the intercooler, maybe i'll call kinsler and ask what the total flow for that big diameter rail is.
And yes that is all my work, I am a 20 year +, design engineer and have been using Solidworks since 1995. Thanks for your input, Very much appreciated. Working on trying to finalize the design, Run some casting simulation on the intake, and then get a 3D printed Sand mold for the manifold and plenum and have then cast. I read in another post about throttle body blade orientation, i currently have the shaft centerlines a 6 and 12 o clock, at first i had them horizontal ten changed to vertical, again for space consideration, i totally get it about the ski jump orientation, but my thoughts were the 5 inch thick intercooler is going to even everything out and straighten the flow to vertical between the upper plenum and the intake ports below, any thoughts on that?

 

You are correct on the inter-cooler basically FIXING any flow distribution issues to the runners so the orientation of the throttle blades in your design are not a big deal. The 1 inch fuel rails are very much like the fuel rails I used for a Hydrogen Fueled 6.8 liter engine. A lot of fuel volume there. I would go with your design initially feeding both from the same end and having the regulator after the fuel rails. Some very nice work there . I worked in Ford Research on Boosted Engine projects and I did the Ecoboost Engine Research Stuff. 39 years doing boosted engine projects. We had some very talented Designers using Catia design software. Keep posting up the updates on your project.

Tom V.

 

Thank you very much for your insite, just had a conversation with Kinsler, he was pretty convinced that i should use a mechanical pump and forget the electric, he said it has way better fuel pressure control because linear flow closely matches rpm increase, therefore the pressure relief valves are not wide open at idle instead thy are making small pressure adjustments, along with the electric amp load can approach 60 amps at high boost straining the electrical system, he also strongly advised the use of a vapor separation tank up front since my tank is in the rear, along with a small priming pump. nice conversation, he also said he is not a big fan of staggered injector flow as it can cause pressure waves that reinforce themselves, and it can be tricky to diagnose because the waves are so small and fast. as far as the fuel rail it is a -12 line size and no problem with enough flow capacity for my 1500 hp limit. as far as the build, i am just about done with the the headders, i had stainless works up and forward, but these pesky 18 degree heads the port spacing was not the same as a normal SBC and the port angle is different, so the headers hit the valve covers by about an inch. so i made new flanges, cut some tubes, lengthened some tubes, and ran them down and forward, with 3in x 180 tight turn bends and a 3rd one perpendicular to the 180, ended up getting the rear of the t-4 flange even with the front of the block and the highest spot of the turbo only 2 inches above the top of the valve cover. Ron Hutter ( Hutter racing Engines) is helping me with the engine design, pretty much a 80s era nascar motor on boost.
Thanks again for your insight, anything you can think or see on my design that may be an issue feel free to speak up, i'm not an ego maniac, i know the best thing is an open mind, and more than 1 helps from getting tunnel vision.

 

I have a lot of respect for Kinsler and for "Earl" one of his long time employees.
If you speak ever to Earl, tell him I said hello. I need to make a trip over to their shop one of these days.
Only a few miles away from me.

Sounds like you have some great work taking place.
We did a 1600 hp 406 cid Pontiac Engine one time on methanol and used 16 of the 160 lb/hr Bosch injectors. 1996 time frame.
Better stuff out there today.

Tom Vaught

 

Nice looking design. I did my runner design on solid works as well. I actuallyrun a 18* twin turbo engine on methanol. The original intake was sheetmetal made by Hogan. I reworked the plenum, made new o-ringed flanges and larger upper plenum section with more volume. The new engine is all billet aluminum with AJPE splayed valve heads. I went with a splayed 16 injector layout that is aimed at the centerline of the intake valve where it transitions to the valve head. I initially used Pro Mod fuel rail from Race Part Solutions that can be directly threaded on the ends to -12ORB. I ended up designing a new injector connection and presented to Jack French that owns Billet Atomizer Injectors. He immediately said he was on board and went into production soon after our meeting. This is the safest design on the market and most EFI manifolds can be converted without any welding involved. The manifold -ORB connection is a standard Mil Spec like all other -AN fittings. They are fed with individual -4AN lines from rails or fuel blocks. Billet Atomizer offers a 8 injector or 16 injector distribution blocks with -ORB supply/return connections. Good luck with the manifold.
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My 18* manifold as modified. Lines and tubing on it is cooling system not fuel.
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SBF manifold with ORB injectors I did for a customer.
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Quote by TurboII, "I ended up designing a new injector connection and presented to Jack French that owns Billet Atomizer Injectors. He immediately said he was on board and went into production soon after our meeting. This is the safest design on the market and most EFI manifolds can be converted without any welding involved. The manifold -ORB connection is a standard Mil Spec like all other -AN fittings. They are fed with individual -4AN lines from rails or fuel blocks. Billet Atomizer offers a 8 injector or 16 injector distribution blocks with -ORB supply/return connections. Good luck with the manifold."

I am glad that people are using the large diameter Fuel Rails when feeding 8 injectors on one fuel rail.
We used similar Fuel Rails on a Hydrogen Fuel Engine about 10 years ago. A LARGE amount of hydrogen Volume was required.
Some really nice Billet Work with your engine.
Love the manifold discussions.
Tom V.

 

I can't wrap my mind around how you'd install the injectors splayed like that with an o-ring connection.

 

It's not as hard as you think and I was not the first to do it. A little o-ring lube does wonders. The ORB style injectors are much safer when you consider 90psi base pressure and 60lbs of boost has the rail pressure at 150psi and only a slip fit o-ring being the difference between success or a major fire. Sixteen 550pph injectors fed by a 21gpm pump moving that much methanol you damn sure don't need to have an o-ring failure. I'll take the ORB route every time.

 

I'm sure projects like this take years, and cubic feet piles of cash, but any updates on this, or prototype stuff done yet?

 

Funny, i am just finishing the patterns. the design is now final, iI am now using a edelbrock baseplate that was used with a 18 deg 2 piece intake. that eliminated a lot of fabrication, So i am casting 4 pairs of port runners that bolt directly to the head and the underside of the lower plenum, and have gone to 1 injector per cylinder now that larger EV14 short injectors with extended nozzle are available from bosch. #ad
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Wouldn't it be cheaper in this day and age to just have them cnc made since you have the cad file? Casting is a lot of work for a one off project, unless you're planning to put it in production?

 

Very nice design work, really nice layout.

One item, though. You've got both turbo compressor outlets attached to each other. What if one turbo flows slightly differently from the other? You might get some surge issues if there is some asymmetry, or some funky wave dynamics in that plenum as you are spooling up. On GN's with two turbos the turbos "mix" in the intercooler, two inlets at the bottom and one outlet at the top for a single throttle body. The intercooler acts as a damper for any waves coming out of the compressor.

You might consider having each turbo feed an individual throttle body just to isolate the compressors a little. In other words, don't have the inlet pipe shared between the two turbos.

 

You may already have done so, the plenum is attached in picture 16 and 17 (or so), but each throttle body is fed by a single turbo in pictures after that. You're ahead of me......

Is this for a particular class? You have about 2000 hp worth of turbos on there...

 

Some very nice design work there. With the way you have the throttle bodies mounted, does the
lower portion of the throttle body blade move towards the plenum and the upper portion move
towards the radiator? We found this feeds all of the runners fairly equally throughout the idle to
fully open modes in the intake.

Tom Vaught