Flow numbers for the predator

[Flyinhillbilly]

I got a message today about 4pm that really brightened my day.
The new head for my predator is done and has been tested on the flow bench.
The numbers on the left are lift, the numbers on the right are the cfm at that lift.
This one should bring the thunder.

 

[KartFab]

Nice! That’s going to be a mean one. Just for comparison this is 35mm in/31ex big block. Blue/red is in/ex before and after.

A stock predator head flows about 65 cfm doesn’t it? That’s a huge jump from 65 to96.5!!!

 

[Flyinhillbilly]

those are big number for a small block head, looks like it’s approaching big block numbers. I hadn’t ever seen numbers for a big block. This is a Tillotson head that’s been worked and has 32/28 valves. I have a welded port warhead coming with 34/28 valves that I’m hoping should be in the realm of 115cfm.

 

[Budget GoKart]

Dang the ports are getting so big wont you guys have to worry about it getting too much air and fuel???

 

[KartFab]

Dang the ports are getting so big wont you guys have to worry about it getting too much air and fuel???

Too much air? Inconceivable!!

 

[Budget GoKart]

Too much air? Inconceivable!!

Ok so when the port is so big it looks like a mail box then what?

 

[Flyinhillbilly]

Ok so when the port is so big it looks like a mail box then what?

Then you’ll need a mailbox sized carburetor
You hear a lot about ports being too big and killing velocity, and while that’s possible, it’s not common. Most of time you’ll run out of material to remove before you get to that point. With these little engines it’s basically impossible to get the ports too big. You can hurt flow by having a bad port job, but as far as size goes, bigger is generally better.

 

[Flyinhillbilly]

Got the head in the mail today and it looks really nice. I’ll get it installed next week and we’ll try it out Saturday.

 

[JTSpeedDemon]

Piece of art!

 

[Flyinhillbilly]

Piece of art!

Thank you, it’s really nice, and was built by the current record holder for stock appearing race engines. I’m thinking that it should bring the thunder.

 

[Flyinhillbilly]

I got it installed and running. It sounds good, so I thought I’d share a little video of it running.
Can anyone tell me how to embed videos from my iPhone? I’m pretty good with wrenches, but not so good with technology.
https://youtu.be/2UWNoR_HOkw

 

[Karts of Kaos]

same here

 

[mckutzy]

Lets see if this works...
Thats so cool.... sounds like a good drum roll cadence on a snare drum...

https://www.youtube.com/watch?v=2UWNoR_HOkw&feature=youtu.be

 

[Hemiwoodworker]

Cant wait, will be looking forward to a video this weekend. Good luck

 

[Flyinhillbilly]

Cant wait, will be looking forward to a video this weekend. Good luck

Thank you, hopefully we don’t get rained out. The weather is looking pretty sketchy for the rest of the week.

 

[thedude306]

that looks beautiful and sounds great. Really neat that you are getting flow numbers to match up the cam. Should be fun!

 

[BLACK DEATH]

How much does a head like that run?

 

[Flyinhillbilly]

How much does a head like that run?

$300
I didn’t get to try it out yesterday because we got rained out, so it’ll be a few weeks before I get to race again, but I’ll let you guys know ho it does as soon as I do.
The nice thing about having flow numbers on a head is that you can see Where it’s the most efficient, and that helps you choose the right cam (it seems the dude understands this). With this one I ended up with .410 lift at the valve retainer, which should be just about perfect.

---------- Post added at 12:41 PM ---------- Previous post was at 12:29 PM ----------

Lets see if this works...
Thats so cool.... sounds like a good drum roll cadence on a snare drum...

https://www.youtube.com/watch?v=2UWNoR_HOkw&feature=youtu.be

It don’t sound much like the 2k rpm idle that it is, but I could listen to it all day.