200 CFM Research

[200cfm]

Ok, this will help me sleep better. So it is possible. Maybe I have received a gift from above on this one port. I tackle this again tomorrow then. At least I know my mind is not playing games on me. Thanks Larry.

[Otto]

i have seen this before on our heads (HD) because of our short port lenght (3.5-4 centerline) the air does not have a chance to stabilize after the radiused inlet befor it has to make any directional changes. My Personal beleif is heads and manifolds should be worked together as a system and a manifold that makes you loose flow is just plain wrong. the manifold is going to bias the airflow into the head at a given angle weather floor roof or side and that is going to determin what truely needs to be done. I have seen jumps of 20% with man verses a flow straighener

That imo

[106-1194218389]

I have seen some very good results adding a good intake. I put the new Performer EPS on my heads and it did lose CFM but was so much smoother it wasn't even funny. My black box gives you a stability reading and the stabilty of the port was substantially better with manifold installed. On my cousins head with his Victor Jr. installed it is much smoother with a slight increase in CFM in some areas. So yes a manifold can be beneficial. Now on the other hand if you put a manifold on the head and it takes a crap then you need either 1-a different manifold or 2-a lot of developement time ahead of you.

John

[106-1194218389]

btw - is that other manifold by any chance for a Cadillac? :;):

John

[200cfm]

It's a small runner 318. A stude enthusiast sent it to me for track testing. Fits the heads fine and supper light. I flowed runner #1 last week and compared it to the current AFB style dual plane iron intake. The torker is around 3% loss and the stude intake is around 13% loss on runner 1.

lift port 1 stude torker loss
.450 173.1 150.3 168.3 13.2/2.8



Tested the torker at the track Friday (hot day) and ran:

run 1: 7.138 @ 93.39 (sputtering and not pulling strong)
run 2: 7.394 @ 91.91 (made throttle change)
run 3: 7.088 @ 96.31 (removed 3/8 spacer insulator)
run 4 : 7.017 @ 96.93 (rejet sec from 87 to 86)

Quarter times: for above in sequence
11.48 @ 109.05
11.789 @ 107.09
11.247 @ 115.58
11.125 @ 117.36

It would accelerate on the back out which is why I dropped the jet. Seemed to help. It idles fine around -15 inches. Stalls to 3400 ok but seems not "crisp". Struggles on the recover shift which pulls back to 4300. Struggles on top end with like 7.5 cylinders. Pops bad on back out too.

Converted back to iron intake for saturday 1/8 only at RDW. Took rear jet back up to 87. weather about same (hot,hot)

Ran: 6.7606 @ 100.56, then ran 6.7555 @ 100.83

Went down on round 1 with a .002 redlite against a breakout dragster. Errrrh! But it ran the dial 6.750

Anyway: Found these "fallout marks" when exchanging intakes.



Any help suggestions please. I have already been informed it is a "bad design" but there has to be a reason for the current failure to perform. Currently it represents more air but less power. And yet runner 3 on the torker is showing a gain in cfm over base. Anyone up to this challenge!

[Otto]

I would check the man velocity. also the increase in cfm is going to change the tune as you noted that it was rich could be seeing more carb signal drawing more fuel may of needed to pull fuel from the intermediate circuits as well. more air = more rpm to reach same port & manifold velocities all else being the same also have seen i my apps generally they will want a timing change as well.in the heat we have to change how we run the bikes higher rpm to get them to perform or they (fall of the pipe) so to speak at the shift recovery points. By no means a expert just my opinion.

[106-1194218389]

Some of these early torkes had poor fuel distribution. We would actually build little dams in front of the ports running rich. Just a small ridge in the base of the plenum in front of the offending port. Sometimes we would build a small hump or peak in the floor of the plenum as needed. Each case was individual of course. Seems like a fuel distribution problem to me. Also take note to the angles the intake ports hit the head ports.

John

[larrycavan]

This is the "combo" scenario we all run into.......It's frustrating when more flow doesn't mean more power.

What does your static data show you? Have you probed it with a pitot while it's mounted without the carb?

Sorted out runner length differences? The motor seemed to like it without the spacer better than with.

What does PipeMax say about the plenum volume vs what the plenum volume is on this vs the other manifold that runs quicker?

Compare the two mainfolds dimensionally as much as from a CFM measurement to see what might be learned....

HOLY SMOKES....we all must have been posting at the same time......There's a few concepts to ponder on this evening. Good Luck.



Edited By larrycavan on 1214872994

[200cfm]

I prepared to port the runners today and my eye caught this.



Started to check all the weld joints and found 8 fuel weep holes. Don't think I would have been alerted if it weren't for the dye. So I wire brushed and JB Welded them all up.

Most were underneath. Here is another one.



Then spent the day cleaning up the ports. They were very raw with nicks, cuts, steps, inner weld bulbs, etc. A lot smoother and wider now. And worked that pinch bolt turn wall on # 3 and # 6 runner. One section of that wall turn was 5/8 " away from the other wall. I got it close to 3/4 but still "choky". Thinking about cutting out the pinch completely and weld in or epoxy in a flat wall.

I hope to retest Friday to see if there is any improvement. Isn't it amazing that you don't know anything until it is put under track load. Thanks for the ideas. May need an epoxy dam too. I don't see those fuel marks at all on the secondary side of the plenum. If it pulls a better mph and et Friday I will push on with the manifold.

[larrycavan]

What do the plugs look like for the two cylinders that correspond to the runners where the fuel was puddling on the divider?

Just wondering which cylinder the fuel was trying to get to when it was rudely interrupted by the roughness annd shape of the casting.

[200cfm]

Hi Larry, will have to check the plugs but since I retested Saturday with the iron intake I probley have lost any reading.
I spent the second day trying to clean up the inside of the manifold. Had lots of dips, cuts, edges, pot holes, steps and over hangs all up inside. And did what I could on #3 and # 6 runner pinch wall turn. When I reflect on the condition of the runners and the leaks I am surprised it ran what it did. But if it can't surpase the iron intake I will give up on it.

Here is a view of what I did today.



And here is the number 3 pinch wall. It had only 5/8" snap gauge distance. Moved it back to slightly over 3/4". Final cure will be to cut the cure wall section out and weld in a flat wall. Wish I was gifted with better tools and talent.



As best I can measure the longest length to the valve is around 10.5" and the shortest total runner length is around 9.5". Pipemax tells me it should be longer to hit the 4th harmonic at peak hp rpm of 5300. Runner entry seems inadequate also. Plenum size is off to I am sure.

Track is racing tomorrow afternoon so if I can finish up in the morning and get it there I will find out if it improves.

[200cfm]

Tested yesterday and the Torker II worked far better with the port work. Made three runs with jet changes in each to see where it might want to be set at.

Run 1: 1.5279 4.3830 6.8267 @ 100.38 on 76/88 jetting.

Run 2: 1.4751 4.3619 6.8417 @ 98.51 on 74/86 jetting.

Run 3: 1.4540 4.2889 6.7283 @ 100.36 on 75/88 jetting

No popping or struggle on the runs. I was happy too.
Removed it today and no issues with the pin hole weld leaks. JB sealed them up tight. Worked on bolt pinch turn # 3 and got the wall moved back now to .815 wall to wall. Stopped there to guard against a hole in the outside wall. Hope to open up #6 pinch bolt turn tomorrow and retest tomorrow evening for the full quarter. It now performs close to the best times with the factory iron dual plane intake for the 1/8. Still looking for that performance gain.

[bruce]

I really enjoy seeing your progress!

A true Do-It-Yourself'er !!!

[larrycavan]

Three tenths and 4 mph......over other posted numbers......looks like you're gaining ground quite nicely.

[200cfm]

Thanks, it gain -1 " more on vacumn idle and is far more "crisp". I reworked the pinch turns on #3 and #6 turn walls this Thursday and wanted to test the change yesterday at VMP for the full quarter but got rained out. On the bench yesterday prior to the reinstall I was seeing #6 manifold port) (just like #3 runner port) pull a higher incline rise on the base line head port than the base line has with radius only. So that runner also peaks up the flow for some reason. Checked the air on # 3 on reference base of .350" lift and got 165 fps midsection manifold runner speed. Highest I could see on the pinch turn of the manifold was 220 fps. Rechecked it again at .368" lift (87% of this .422 max cam lift) and got 187 fps for the midsection runner and 224 fps on the pinch turn. Checked the midsection on manifold runner 6 and got 180 fps.

Next week I hope to pull the intake, work the choke turns a little more to make the radius longer. Isn't it great to go back to school again an learn.