Time to go Stage II!

[Alky V6]

Machining the intake flanges to accept a 1/4" thick lifter valley cover.

 

[Alky V6]

Still got a lot of trimming to do on the flanges.

 

[Alky V6]

With the flanges mounted to the heads, I can use a scribe to exactly mark the intake port sizes onto the flanges.

 

[Alky V6]

Now, I'll put the angle into the long walls by hand, then I'll mount the flanges in the mill again and bring the rest of the port walls to their final sizes. The taper will then be put in by hand.

 

[BlownV6]

Now I'll put the angle into the long walls by hand, then I'll mount the flanges in the mill again and bring the rest of the port walls to their final sizes. The taper will then be put in by hand.

View attachment 161978

Leave yourself some room to do the final port match after all welding and final flange to head machining are finished. When you set up to weld the final assembly together , set it up so that the ports are all higher than the ports in the heads. The manifold will warp quite a bit and this will allow you to mill the flanges to an exact fit to the heads. Love your post here ,and wish I still had your energy and time!!! Mike

 

[Alky V6]

Leave yourself some room to do the final port match after all welding and final flange to head machining are finished. When you set up to weld the final assembly together , set it up so that the ports are all higher than the ports in the heads. The manifold will warp quite a bit and this will allow you to mill the flanges to an exact fit to the heads. Love your post here ,and wish I still had your energy and time!!! Mike

Hah! I know what you mean. What did I get myself into?
The intake is going to be a bolt together. A little more refined than the Stage I intake, but following the same idea. The runners will bolt to the flanges, so I won't have to worry about any final machining or port matching due to any warpage from any welding involving the flanges. The Stage II head layout makes the bolt together concept extremely easy to accomplish. There's tons of room.
Even the lifter valley cover will be bolted to the flanges so that the cover becomes a stressed member to help the block out. Final fitting of the lifter valley cover won't occur until the heads and intake flanges have been properly torqued into place.
O-rings will be used to seal the runners to the intake flanges and the plenum.

 

[bison]

What RPM have most of the fastest SII V6 guys turned normally?

Less than 8000 rpm to run 7's.

 

[Alky V6]

Less than 8000 rpm to run 7's.

It'll be over 8,000 being destroked and with fewer cubes. I'm figuring around 8,700. At about the natural frequency of the present driveshaft.

 

[bison]

It'll be over 8,000 being destroked and with fewer cubes. I'm figuring around 8,700. About the natural frequency of the present driveshaft.

At least the driveshaft speed is more relative to mph at the top of 3rd. If you need it it will be a relatively cheap investment at this point.

 

[Alky V6]

At least the driveshaft speed is more relative to mph at the top of 3rd. If you need it it will be a relatively cheap investment at this point.

Agreed. I'm going to wait and see what the car wants. If traction becomes an issue, even on a good track, then I'll be doing some major chassis work, which will most likely mean a different driveshaft dimension. Only want to buy a driveshaft like that once.

 

[Alky V6]

If I change gears from the 3.73 to a 3.42, that would put me at around 8300 across the finish line, assuming a 16% TC slip with the higher gear. I'll wait until the car is back running before I make that decision.

 

[Alky V6]

I know. TC slip is still another factor to be looked into. That will be left for last, when I have some real world numbers to look at.

 

[Alky V6]

I figured out a way to machine the angle into the long walls.

 

[Alky V6]

All that's left is to blend in the radii and finalize the amount of taper to add to the walls, and which walls to add the taper too.

 

[Alky V6]

I have an interesting problem with the runners. The sim is showing that an intake runner length of 2.0" would work extremely well for peak hp, sacrificing a little low end.
The stack up looks like this. The intake flanges are already 3/4" thick. The plenum wall thickness will be 1/8" thick, and the runner entrance plate with its radiused entrance will be 1/2" thick. That leaves the runners being 5/8" thick?
The runners themselves are going to be very short suckers. This is going to be interesting.
I think the bolts will be going clear through the complete stack up, just like the Stage I manifold.
And, I still have to mount per runner, 2 electronic injectors, one mechanical nozzle, one nitrous nozzle, and one cold start priming nozzle. What a cluster fandango. This is going to take some creative imagination.

 

[turbobitt]

I have an interesting problem with the runners. The sim is showing that an intake runner length of 2.0" would work extremely well for peak hp, sacrificing a little low end.
The stack up looks like this. The intake flanges are already 3/4" thick. The plenum wall thickness will be 1/8" thick, and the runner entrance plate with its radiused entrance will be 1/2" thick. That leaves the runners being 5/8" thick?
The runners themselves are going to be very short suckers. This is going to be interesting.
I think the bolts will be going clear through the complete stack up, just like the Stage I manifold.
And, I still have to mount per runner, 2 electronic injectors, one mechanical nozzle, one nitrous nozzle, and one cold start priming nozzle. What a cluster fandango. This is going to take some creative imagination.

Mechanical injector and Nitrous nozzle could probably run in the interior ?

I am also surprised at the 2" runner length. Using the simulator, I would think that you can reach another more optimum length for fabrication.

Looking at big inch super stock Hemis making about 1000 HP normally asperated, they have very long runners that cross over each other to take advantage of manifold tunning. Since you are big on this concept, I would think that there would be several lengths that could be used that would yield the same results.

Allan G.

 

[Alky V6]

Mechanical injector and Nitrous nozzle could probably run in the interior ?

I am also surprised at the 2" runner length. Using the simulator, I would think that you can reach another more optimum length for fabrication.

Looking at big inch super stock Hemis making about 1000 HP normally asperated, they have very long runners that cross over each other to take advantage of manifold tunning. Since you are big on this concept, I would think that there would be several lengths that could be used that would yield the same results.

Allan G.

I've tried different lengths. As soon as I add just one inch, peak hp begins to drop. Especially with that first one inch. Almost a 100 hp drop.
For sure, the mechanical nozzles will be interior. Primers will be mounted to the roof of the plenum.

 

[Alky V6]

The sim showed the same sort of gains with the Stage I project. The runners were not as short as 2.00" though.

 

[Alky V6]

I'm thinking with the nitrous nozzles, on the left side long wall of each runner, looking at the runner from the sides of the engine. One E injector at the traditional location, and the other E injector on the opposite side of the runner, under the plenum. With the way the runners will be angled, there will be tons of room under the plenum.

 

[turbobitt]

I've tried different lengths. As soon as I add just one inch, peak hp begins to drop. Especially with that first one inch. Almost a 100 hp drop.
For sure, the mechanical nozzles will be interior. Primers will be mounted to the roof of the plenum.

When working with tunned runners, I would think that you would need to double or tripple the length to get you back to the same optimum fequency. 1 inch may start dropping power but there should be a point where it starts to pick up again ??

Allan G.