If you hit the sweet spot with the right combination the engine should make impressive numbers. My money is on you and Jim.
Aluminum 409 Build
- Thread starter jim_ss409
- Start date
I'm calling Simpson.............I want to get a brand new, current set of approved 6 point harness for my easy chair for the computer. WHY???????? 'Cause this thread is going to be a hellva ride and I wanna be safe and last until the end!!!!!!!!!!!!!!!!!!!!:eek
CHICKEN!!!!!!!!!!!
They say a picture is worth a thousand words so I made a paper template showing what the spacer will look like. It will be about 1 1/4" thick and be made out of aluminum.
Four head bolts will pass through it to help clamp it into place. It will also be fastened with a few bolts into the head. I think we'll just use epoxy to seal and hold everything but it could get welded down.
Four head bolts will pass through it to help clamp it into place. It will also be fastened with a few bolts into the head. I think we'll just use epoxy to seal and hold everything but it could get welded down.
I'm calling Simpson.............I want to get a brand new, current set of approved 6 point harness for my easy chair for the computer. WHY???????? 'Cause this thread is going to be a hellva ride and I wanna be safe and last until the end!!!!!!!!!!!!!!!!!!!!:eek
And you're on Pepsi Phil?
So 800 HP in the light Pontiac. How fast is it now and what do you think it will do with the new motor?
Don
And you're on Pepsi Phil?
So 800 HP in the light Pontiac. How fast is it now and what do you think it will do with the new motor?
Don
We're hoping for about 9.50's
you could practice on mine.
We've made some progress on the heads.
We milled down the rocker pedestals. We're sure the T&D rockers are going to fit after a few minor adjustments.
We made a thin template of the spacer and tomorrow we're bringing it to a local shop that will copy it into a CNC program. They will then cut us out a spacer from 1 1/2" aluminum using a CNC controlled water jet cutting machine.
As you can see the intake face slants back toward the center of the head so the higher it goes the closer it gets to the pushrods and rockers.
To make sure we had enough clearance, we added a 3/8" thick plate to the intake surface.
We didn't cut the ports in yet. Since the Pontiac doesn't use a thermostat we just tapped the water crossovers to 3/4" pipe thread.
The plan is to build a two piece intake with the valley pan separate from the intake runners. We're still hoping to raise the runners about 1 1/4" but I'm sure we'll get at least one inch.
I'll post some more progress pictures as soon as we get the spacers.
We milled down the rocker pedestals. We're sure the T&D rockers are going to fit after a few minor adjustments.
We made a thin template of the spacer and tomorrow we're bringing it to a local shop that will copy it into a CNC program. They will then cut us out a spacer from 1 1/2" aluminum using a CNC controlled water jet cutting machine.
As you can see the intake face slants back toward the center of the head so the higher it goes the closer it gets to the pushrods and rockers.
To make sure we had enough clearance, we added a 3/8" thick plate to the intake surface.
We didn't cut the ports in yet. Since the Pontiac doesn't use a thermostat we just tapped the water crossovers to 3/4" pipe thread.
The plan is to build a two piece intake with the valley pan separate from the intake runners. We're still hoping to raise the runners about 1 1/4" but I'm sure we'll get at least one inch.
I'll post some more progress pictures as soon as we get the spacers.
Hey Carl, save some for me!
may be a bit of a drive but......
Great to have you here Bossman. We sort of making this up as we go along so we're open to any input you may want to offer.
We're hoping the spacer plate will be done later today.
Here's another view of the port that I drew some lines on...
We will certainly be able to reduce the angle at the turn and I think we should be able to get the average cross section area up to a more appropriate size. As it is now the CSA at the pushrod pinch is pretty small, just over 2 square inches. My intake design program (Pipemax) recommends over 3 square inches for this size of engine.
The port would be even better if it was shaped more like the one in this picture. In this port the air gets to straighten out after the turn and flow out around the entire circumference of the valve. With our heads the air will mainly skip over the back of the open valve but I'm still hoping for a good improvement.
We sort of making this up as we go along so we're open to any input you may want to offer.We're hoping the spacer plate will be done later today.
Here's another view of the port that I drew some lines on...
We will certainly be able to reduce the angle at the turn and I think we should be able to get the average cross section area up to a more appropriate size. As it is now the CSA at the pushrod pinch is pretty small, just over 2 square inches. My intake design program (Pipemax) recommends over 3 square inches for this size of engine.
The port would be even better if it was shaped more like the one in this picture. In this port the air gets to straighten out after the turn and flow out around the entire circumference of the valve. With our heads the air will mainly skip over the back of the open valve but I'm still hoping for a good improvement.
I know Pipemax well, porting, flow work its what I do. I competed in Engine Masters this year with that Early Hemi "Hot Heads" team (I did all of the induction related work) got Runner Up & Torque Monster in the Street class. 3" CSA would be really nice to achieve but I will guess you need to be 3.6"+ over the short side. How big of a valves are you planning on running?
Yes, I followed your progress on that engine on Speedtalk and in Engine Masters Magazine. I put a link to an Engine Masters article on your intro thread. It's a great story...
http://www.popularhotrodding.com/tech/1211phr_388ci_chrysler_gen_i_hemi/
Check out the Injection setup Bossman made for that engine.
The valves are 2.25 intake and 1.75 exhaust. They are almost touching so that's as big as we can go. I think if a guy was starting with new heads, it might be better to go with 2.3 and 1.70 for this big bore engine.
The bowl area looks pretty big but I guess what you're getting at is that the air will have to expand and slow down to get around the turn so it's the port size works with the bowl size.
Again I have very little experience but looking at most good ports I can see that they get larger before the valve...
The good news is, all I have to do is rough in the port, taking care not to remove too much material. Dave Mills will do the real porting. He's been experimenting with raising the ports on the 409 head for a while.
We'll build a tunnel ram. Right now I'm thinking we should be able to come straight off the the runner and not have any bends. The runners will probably be a little shorter than I'd like but we'll bring them to a tuned length.
I'm thinking we'll go with a seperate valley cover.