Making a intake manifold for my 4-71 blower

[Sidewinder]

We was very pleased after todays workshop
Got a good start making the new manifold for my flathead.
Next up is for me to grind the portholes smooth and to match the block.
Roger is gona make a 1 1/2" tall plenum with the pop-off/burstpanel pointing forward this time
After we have fitted the plenum, we'r gona make the bracket for the blower-belt tensioner. We also need to make some supports for it and for the plenum. Last is to make holes for oil filler and breathers.
Have gotten some heads-up regarding port nozzles, so we'r gona make provitions for them

Kjell

[GlennLever]

I like!

Keep the updates coming!

[KING CHASSIS]

 I love homemade stuff.   Keep us up dated buddy.   See ya in a couple of years Kjell.

[denverflatheader]

Sidewinder – sorry so slow to respond.  I had gone back home to islands this week for family business, was pre-occupied all week long.  Back in Colorado now.  Thanks for your comment on my intro, yep have a funny location for seating on 999 car but is very comfortable with nice view.
 
Burst panel pointing forward sounds good, little safer direction for you and also helps set the intake manifold height.   You could go with a little lower intake manifold height if you designed burst panel at angle (laying back) versus straight up 90 degrees from top of block.  I’m guessing it will be set straight up 90 degrees so you have more clearance with your Baron Racing Heads, they’re tall ones.  I think you already accepted your vision down track will be obscured  : )
   
Heard before it’s good idea for port nozzles in addition to your hat nozzles with nitro.  I think the closer to the intake valve you can locate the better.  (You might ask “Spud here” for his thoughts on port nozzle placement).  With fh, it’s little bit more challenge compared to oh valve to design.  You and your crew chief probably already know this…..  port nozzles on fh can be a piston saver.  I’ve heard from “excellent source” the four outside corners pistons run a little hotter/leaner than the four middle pistons.  Keep one eyeball on it, or you might melt a piston top (actually another good question for you to ask “Spud” how to read spark plugs to prevent melting your piston with 20 lbs boost on 50%+).
 
Remember how the four outside cylinders’ exhaust are cast and wrap around the cylinders as part of the block casting…..   creates more heat.  Plus with 4-71, wide open the hat nozzles (2 or 4 nozzles?) might help some cylinders run little bit richer than others (again, another question you might ask “Spud”  i.e. rotor clearances, stripped or not, size 4-71 vs. 14-71, how affects fuel distribution).
   
You’ll have fun troubleshooting and adjusting (increasing) size of port nozzles to compensate for leaner cylinders.  Port nozzles aren’t like slicks, they don’t have to match exactly  : )   DF

[Sidewinder]

Thanks DF:)
You are spot-on. I was thingking of placeing the pop-off/burstpanel slightly downwards or uppwards, to save some space. The plenum will be made with an angle to match the flow towards the outher runners. I'm gona bring the intake to Roger to weld some moore, as i have grinded off abit;)
I have looked at the port nozzle angles, and I think they will match the runner angle and spray straight down towards the ports in the block.
At the moment we have 4x64A Hilborns in the hat. The port nozzles will come a litlebit later. We'r gona tune it with straigt alky, and then we shall see if we switch to pops:)! It's gona be interesting to see if the fuel distribution is working with this design!?

Kjell

[GlennLever]

There is also a Mini brust panel. I thought of usinging in my application but was unsure how track inspectors would look at it

"SFI approved mini burst panel. This panel is a must for high boost applications and will keep the supercharger and manifold damage to a minimum. If the engine over revs or engine tune up is not at maximum performance. Mini panel measures 4.250" x 2.375" and has eighteen mounting holes. "

http://www.rbssuperchargers.com/Products.cfm?pn=2000-0001M&pID=8353

[denverflatheader]

Sidewinder - yes, when she together and ready for 1st outing, I’m guessing alky should work hunky-dory.  Each pass will provide more confidence. 
"Excellent source” shared with me on his blown injected fh, straight alky ran so smooth once dialed in (like bracket car).  Then switching to “pop” look out as that’s when “trouble” reared its ugly head (lean-rich cylinders imbalance), but worth it, et-mph wise.  Your crew chief knows, best to ease into “snap crackle pop” and adjusting timing to hit the mark : )   I know it's a way off but fun to "dream" about it : )
   
You might consider asking “Spud” for his thoughts too on your plenum design.   He probably already knows what works good, and more importantly, what will work better for 4-71, and 255-286 cubic inches.  I only spoke to him once on the phone, and can tell he has it together upstairs.   

Glenn – I didn’t know about those baby burst panels.  Ideal to pair them up, one on each side versus a larger one in front……  simple way to lower plenum height.   Seems to me two panels opposite and inline with intake ports is better design than just one in front.  DF

[Sidewinder]

Thanks Glenn & DF on your inputs!:) Spud has answerd me on some magneto issues, so now I have solved foult nr. 3. With all these issues solved I'm optomostic on taking the "winder" faster down the track:) Last year we whent to the HAMB drags, I bought a couple of pop-off plates, one Cragar and one Weiand (say-why-and), and was thinking of useing the Weiand, and switch to burst. I thinks they have the same size.
We have made new rules, so pop-off is still leagel here:)
The plenum might not be perfect or 100% ideal, but there are some stuff we need to compromise on. We plan to have the plenum approx. 1- 1 1/2 inch high abowe the runners. Roger has the intake now for some more welding, but hope to have it back soon for some more grinding, then he could fit the plenum. We allready had the top-plate, as it acted as a spacer on the old one:)
Anyone have any idea what sparkplugs to start with? NGK BP5ES? I have allways used Champion on my gas engines.

Kjell

[denverflatheader]

Sidewinder - I’ve only made a few parts from aluminum alloy, always used 6061-T651.  Though my mid-plate for the six is 7075-T651.  I’m probably luckier than most, as there is an aluminum recycling business a few miles down the road.  They have new, used, leftover just about anything you can think of, round, tube, square, flat, etc.   They’ll also do minor cutting and braking for you.  They sell by the pound, and I’m usually spending under $20 for what I need.  They have these racks with small cut pieces, usually can take my cardboard template and match up a pre-cut piece real easy.
 
I’d have to say of all the things I’ve had to do on the dragster, ranking right up there is deciding and designing those little aluminum pieces are most fun.  Your making a blower intake, lots more fun, and more complicated.  That’s one definition of the word “custom.”    DF         

[ricardo1967]

Thanks Glenn & DF on your inputs!:) Spud has answerd me on some magneto issues, so now I have solved foult nr. 3. With all these issues solved I'm optomostic on taking the "winder" faster down the track:) Last year we whent to the HAMB drags, I bought a couple of pop-off plates, one Cragar and one Weiand (say-why-and), and was thinking of useing the Weiand, and switch to burst. I thinks they have the same size.
We have made new rules, so pop-off is still leagel here:)
The plenum might not be perfect or 100% ideal, but there are some stuff we need to compromise on. We plan to have the plenum approx. 1- 1 1/2 inch high abowe the runners. Roger has the intake now for some more welding, but hope to have it back soon for some more grinding, then he could fit the plenum. We allready had the top-plate, as it acted as a spacer on the old one:)
Anyone have any idea what sparkplugs to start with? NGK BP5ES? I have allways used Champion on my gas engines.

Kjell

Sidewinder - I'd think that the NGK BP5ES plugs are a little too warm for a racing environment. Even some factory cars in Brazil were fitted with colder NGK BP6ES or even NGK BP7ES (for ethanol, with 12.3:1 compression). I personally have gone as cold as '9' on street/strip turbocharged engines. The FED currently has NGK R5672A-9 on an alky SBC 400, AFR 220 heads, with ~12.5:1 compression.

[Garyr]

I would recommend "9"s by NGK they are very easy to read on the threads. Keep the boost levels down on the flatty as you only have 3 mains . We ren a bonneville car with a dry sump system and you can't put too much oil pressure on it because it'll leak by the pan seals.
Good luck the manifold looks better than the ones I make out of 4bbl manifolds.

[wideopen231]

The sheet metal on my new car is one I made. Did little different. I started with 1/2" thick pice aluminum and machined it to match ports.

  I bolted a set of heads down to block,molted the new flanges to heads and then added the runner I had formed around a wooden block I shaped for match what i wanted runners to be.This way i had 8 runners the same size and shape.

  I then trimmed tops of runners and made a valley plate for each side. Iwent a welded as much of the bottom of runners and flanges as I could. I then removed and fished welding the rest.
  Re bolted to head and added valley plates and then finished of the fron and rear of valley.
  Next I added a top plate to allow me to bolt my injector to. Ive got some cleanup of welds and little surface prpep and it will be ready to rock n roll

[Sidewinder]

I would recommend "9"s by NGK they are very easy to read on the threads. Keep the boost levels down on the flatty as you only have 3 mains . We ren a bonneville car with a dry sump system and you can't put too much oil pressure on it because it'll leak by the pan seals.
Good luck the manifold looks better than the ones I make out of 4bbl manifolds.

Thank's for Your advice Garyr:) So far no leaks, With 80-90 psi of oil pressure (wet system).
Our current set-up gives us 24 psi of boost. I know this is alot for the 3 mains, but we have chosen good Products in the bottem end.
We have a Moldex billet crank With large journals on the connecting rods. Thoose are Crower I-profile ones. Custom Ross pistons that are coated. Total seal, gapless rings.
To match this we choose a one off Crower cam With roller lifters. Oh forgot to tell you about the cutom billet mains an girdle.
I did some grinding on the inntake today, and hope to do some more Welding soon, as spring is around the corner:)
48 New ARP bolts is on it's way too, so we can mount the new Baron Heads:)

Kjell

[GlennLever]

I would recommend "9"s by NGK they are very easy to read on the threads. Keep the boost levels down on the flatty as you only have 3 mains . We ren a bonneville car with a dry sump system and you can't put too much oil pressure on it because it'll leak by the pan seals.
Good luck the manifold looks better than the ones I make out of 4bbl manifolds.

Thank's for Your advice Garyr:) So far no leaks, With 80-90 psi of oil pressure (wet system).
Our current set-up gives us 24 psi of boost. I know this is alot for the 3 mains, but we have chosen good Products in the bottem end.
We have a Moldex billet crank With large journals on the connecting rods. Thoose are Crower I-profile ones. Custom Ross pistons that are coated. Total seal, gapless rings.
To match this we choose a one off Crower cam With roller lifters. Oh forgot to tell you about the cutom billet mains an girdle.
I did some grinding on the inntake today, and hope to do some more Welding soon, as spring is around the corner:)
48 New ARP bolts is on it's way too, so we can mount the new Baron Heads:)

Kjell

There is a flat head hinding in there somewhere!

[Sidewinder]

YES !

K