1bad91Z

iTrader: (1)

Not trying to pee on parades or anything, but wouldn't you be better off and less time/money just fabbing a sheet metal intake like one of the many that Hogan's make?

gregs78cam

Actually the intake flange is situated at 35* from horizontal. That puts the roof of the intake port at about 46* from vertical, which is just about the entry angle of the runner.

I will gladly take a small increase in angle here in order to have the injector pointed directly at the valve instead of at the floor, like most EFI manifolds have. I do like the port/injector configuration that the OP is going for.

1989GTATransAm

iTrader: (3)

Probably, but the idea is to make this thing look like an Accel Super Ram which is California smog legal. IMHO one of the keys is the front water jacket area which I want to retain. Also the EGR.

gregs78cam

In the 4 different designs I have drawn up that seems to be the underlying issue.

Orr89RocZ

iTrader: (20)

Run a remote waterneck and a crank trigger EFI system like LS1 and your set Not smog legal I guess but could give others the room.

Atleast remote waterneck housing for front space.

1989GTATransAm

iTrader: (3)

If I had a free hand the design would be different for sure.

Jim85IROC

iTrader: (2)

somewhere in one of my books, the author discusses injector angle and talks about wgy they usually aren't aimed at the valves, and he makes a convincing arguement against it. I'll try to find it and post a summary.

Russ-So Cal

I haven't read anything on injector angle, but logic tells me that if it is pointed at the back of the valve and the spray hits the valve, the fine spray pattern may flood and kill the atomization of the fuel.

ASE doc

Fuel atomization with port fuel injection is mostly created by the pressure differential between inlet air and fuel from the injector nozzles. The higher the nozzle pressure, the better the atomization, at least that's the theory. It seems to prove out in my experience. It's alot the same as the ventury in a carburetor, except that it takes place in the intake port of the cylinder head rather than at the throttle.

One factor that makes a real difference, at least in fuel efficiency at lower engine speeds is sequential verses batch fire injection. In sequential, the injector is firing when the intake valve is open and as the air is being drawn into each cylinder. With batch fire, the injectors all fire together every turn of the crankshaft. Meaning some intake valves will be open, others will not be. This means that at lower revs, the fuel in some cylinders is going to sit for a moment behind a closed valve before it's drawn into the cylinder. At low engine speeds, this will have a negative effect on efficiency. As engine speed increases, it has less effect since fuel droplets move at a constant speed while the engine cycles faster. At some point, the fuel and air are moving almost at a constant velocity past the valves and into the cylinders.

1989GTATransAm

iTrader: (3)

I have told this story before but worth the repeat. When I was going from a 3-bar fuel pressure to a 4-bar fuel pressure, as we were cranking up the fuel pressure the idle kept getting better and better. I am now run at 58psi of fuel pressure. Kevin adjusted the table accordingly.

gregs78cam

This is my point. Firing the fuel at a hot valve will help to keep it vaporized for the few milliseconds that the valve is closed.

With sequential EFI, it is not an issue.

TTOP350

iTrader: (8)

I have always run 50-3 fuel psi. It always seemed to run a lil better than the next guys car..

ASE doc

Of course, I didn't mean to imply that ideal injector angle isn't of real value. I would say in fact that, even with sequential injection, having the injector fire directly at the open valve, rather than at the port wall, would be beneficial.

Of all factors to consider however, I think that the most important is a smooth path for air flow with as gradual bends as possible, if bends are necessary. Ideal injector angle, to my thinking, is secondary to this. Just my opinion.

As far as fuel pressure goes, the newer factory systems run as high 80psi.

ASE doc

One thing I just thought of is the effect of spraying cool liquid on a hot valve. Could this cause warpage? If the fuel pressure was high enough, the fuel spray would atomize into a mist of fine particles. That might help prevent problems.

Russ-So Cal

I think that with an aluminum manifold absorbing heat from the engine, and the the heat that is created when the pressure is boosted, you probably don't get really cold fuel being sprayed on a hot valve.

1989GTATransAm

iTrader: (3)

Another update. We have cut up the runner material to size and they are ready to be welded together. After some careful measuring of everything I decided to go with 1.5 degree of taper. That is about as much as I can do and have everything fit. Here are some pictures of a runner with the two halves clamped to gether and one looking down the inside of the runner.

1989GTATransAm

iTrader: (3)

The runners are now back from the welder. I am now down to 8 pieces from 16 halves. Next there will be 4 paired runners. Removing the exterior weld will be a peace of cake with the mill. The interior welds will test my skills. Here are a couple of pictures.

ASE doc

Good to see the progress. I'm excited to see the completed assembly.

1989GTATransAm

iTrader: (3)

Me too.

1989GTATransAm

iTrader: (3)

Took the base over to my friend Pat's house and we fitted it up to his long block. I wanted to see how the machined ports now line up with his AFR heads. It is looking real good. The angles look to be right on with the roof and floor of the AFR head.

I also held in place one of the new runners in the location it will be in and there is no problem looking right down the port at the back of the intake valve on port one. On port 3 you can see about a fourth of the intake valve because the port turns the other way. If a straight line means anything in a intake manifold runner this is going to be good.

Orr89RocZ

iTrader: (20)

On my engine pro software, which was developed using results of many thousands of engine dyno data, a straight runner does mean less flow loss and more power.

1989GTATransAm

iTrader: (3)

That is what I understand to be the case and what I am counting on. By the way here is a picture of one of the runners with the weld removed from the inside. Not the best of pictures.

1989GTATransAm

iTrader: (3)

I have the heads in my garage to open them up some and make sure they are as wide or wider than the TPI Cross Ram base. Then I thought it would be neat to take some pictures to get an idea where we are going with this. I proped up one of the runners in just about the position of where it will go and took the pictures. One of them is looking right down the runner into the back of the intake valve. Here are the pictures.

ASE doc

Wow! I can hardly wait to see this thing completed.

1989GTATransAm

iTrader: (3)

A little update. I have now paired the runners. Started with 16 parts and I am now down to 4. We did some more machine work to the base but here are a couple of pictures of the paired runners. By the way the welds on the corners will be machined squared and the material for the bell mouth will be welded on.

ASE doc

I can really see it coming together now. I'm still curious to see the transition between the extruded tubes and the base.

1989GTATransAm

iTrader: (3)

The transition from the extruded runers to the base will be welded on the inside and some on the outside. I will then hand grind what I need to make a smooth transition between the two parts. The more I think about it this intake has a lot of potential. The dyno results should be interesting.

Long Beach Z-28

iTrader: (1)

"The dyno results should be interesting"

I just hope the engine you choose to dyno your Cross Ram with will be able to do your Cross Ram justice.

You should know by this Friday afternoon, a little bird tells me

Talk to ya soon.....

ASE doc

This manifold will definitely support top end power, assuming the plenums have adequate volume to allow the runners unobstructed air flow. The interesting thing will be to see it's torque curve and how well it supports low to mid range torque. I'm hopeful to see a very long, flat torque curve. I would say you certainly want a cam and heads that will support 7,000 rpm for this bad boy.

1989GTATransAm

iTrader: (3)

"You should know by this Friday afternoon, a little bird tells me"

The results should be interesting. The runners are back over to the welder to have the bell mouth material welded on.

1989GTATransAm

iTrader: (3)

The results were interesting. 576HP on the engine dyno. Hmmmm, that will really put my TPI Cross Ram to the test. I doubt if it will match that.

Anyways I have a couple of pictures to post showing where I am at on the base with everything lopped off. Should have updated pictures of the runners next week. Found out something interesting. The new EV6 injectors are only 48mm tall or about two inches. Using them would simplify this project and allow me to increase the plenum depth. I will have to look into it. Here are a couple of pictures.

Jim85IROC

iTrader: (2)

LS3 injectors are short too, and commonly available cheap.

Long Beach Z-28

iTrader: (1)

Glad we didn't buy any new injectors yet

I was thinking that were gonna need some 36# ers now with the 576HP!

I wonder if the 36# injectors are gonna be enough???

1989GTATransAm

iTrader: (3)

Normally you would be right but this is a totally custom deal and I need the plenum to be as low as I can get it. The bottom of the plenum needs be .500" above the fuel rail so that I can install it and remove it. So the LS3 injector would allow me another 1/2 inch in which to lower the fuel rail and in turn lower the floor of the plenum a like amount.

I just happen to have a set of extenders for the LS3 injectors. With those they are still a 1/2" shorter than the Bosch 3 injector and 5/8" inch shorter than the original factory injectors.

1989GTATransAm

iTrader: (3)

Pat, the next time we meet up I will show you what I am talking about. So let's not buy anything until I have a look see when I go back to the machine shop on Thursday. I have relocated the fuel pressure unit to fit under the drivers side fuel rail. So I will need clearance for that and that could put a hitch in things.

GTA Sammy

iTrader: (1)

I'm sorry, but did I miss something?
Which Engine, Intake, Cam, Heads made 576 HP?

By the way... I love what your doin!!!

1989GTATransAm

iTrader: (3)

Ok, here is the deal. My friend Pat has a 383 sbc that has ported( by Dr J) AFR 195 heads on it. We are going to use it as a base to try out my TPI Cross Ram on. In the meantime Pat had it put on the engine dyno at Westech Performance in Mira Loma California with a carb system to get a base line. When it was all tuned in it put down 576 HP.

Westech is also set up for EFI and they have done lots of them and also with a lot of experience in that area. So when my TPI Cross Ram intake is done we will put it on Pat's 383 long block and take it out to Westech and see how she does. The 576 HP mark will be a tough one to match. That is down right awesome in any ones book.

KrisW

iTrader: (5)

Tagging along to see what happens.

Subscribed

Orr89RocZ

iTrader: (20)

576whp may be ok on 36LB injectors at higher pressures...but I'd go 42's to be safe if running 43psi pressure. My friend makes near 615hp on motor which is based on the 521whp it made..and its 42lb injectors are pretty high on duty cycle

1989GTATransAm

iTrader: (3)

Right now there seems to be some "take-out" LS3 injectors on the market at a decent price. I believe they are 42lbs. The EV1 to EV6 connectors are like $40. If this work I will go that route.

ASE doc

Lol. I just now noticed the pictures of the stripped down manifold base before the runners are installed. About what I expected. Not much left of that thing. Just coolant passages and a cover for the cam valley.

1989GTATransAm

iTrader: (3)

Right. I will probably remove some more material between the coolant passages and the cam valley cover. At this point I am feeling my way along regarding the base. It is easier and cheaper to remove material than to add some back.

1989GTATransAm

iTrader: (3)

Here are some pictures of the runners. They only need to be cut to length and some minor cleanup. They are pretty much done. Now to mate them to the base, get the correct angle and weld them in. Once that is done on to building the plenum.

1989GTATransAm

iTrader: (3)

Some very good news. I will be able to use the LS3 EV6 injectors. I was worried about the clearance for the fuel pressure regulator but it will clear. Also there is enough clearance for the EGR valve. This will simplify the construction of the plenum by allowing me to lower the fuel rails a 1/2 inch. Notice the new location of the factory fuel pressure regulator.

ASE doc

I don't think your cross ram will have any trouble out pacing a single carb setup. The limiting factor will be the engine's ability to move air. You are creating 8 balanced, ultra high flowing runners. Now you just need to attach plenums that provide unobstructed air flow to the runners and hopefully avoid any sharp angles or sudden changes in CSA. No single carb intake can match that. The Victor comes close but even it is a compromise of runner balance and physical limitations.

1989GTATransAm

iTrader: (3)

Here are a couple of pictures of the runners in place at one end. At this point the runners are 1.125" to long. They are going to be shortened by a like amount. Also a shot down one of the runners with more work to be done. Hopefully ASE doc you are correct with your assessment. Here are the pictures.

ASE doc

Wow! Beautiful! That thing is going to look nasty. Of course you need to do some work on the transition where the runners meet the base. I've been thinking that this will be your key challenge. Making that transition smooth. So far it's looking great.

Orr89RocZ

iTrader: (20)

Interesting setup. Curious to see how the plenum will look. I recommend a twin plenum/tb setup like the viper V10's but getting that to work may prove difficult with throttle openings. Drive by wire would be nice here

ASE doc

I've been thinking about the throttle set up too. Several factory engines have used dual throttles, even the old 3.5 Chryslers had dual throttles. It would be tricky but the linkage could be adapted to this application. The key would be balancing the throttles.

1989GTATransAm

iTrader: (3)

The floor of the plenum will be about a 1/2" below the bellmouth entrances. It will initially be in two pieces with each piece cutout for the runners and slid in from each side and meeting in the middle. It will then all be welded together. The plenum will be supported by the runners. Once the plenum floor is in place the rest of the plenum can be built up and when it is all said and done it will resemble the Super Ram plenum.

Where the runners meet the base it will all be welded up internally and externally and then I will grind it out for a smooth profile with the correct cross sectional area. It will blend in nicely. It just looks rough at this point. I will be using the standard TPI style throttle body.