intake port molds

[tpepmeie]

Got the port molds done. Pretty neat to see an LT5 port from the inside out. Also helped me confirm the cross-sectional areas.

here are primary and secondary head port (right), and also primary and secondary injector housings (left). Pay no attention to the lengths... I didn't get a "full pour" on a couple of them. In this pic, you can't see just how unfortunately large the bowl is behind the valve, as cast. We discussed seriously about welding that or using some epoxy to reduce the volume there, but didn't do it.

http://www.photohost.org/gallery/data/500/2374IMG_2022small.jpg


Todd

[Locobob]

You can see a lot more in some other pictures, but afraid those angles might be giving too much I.P. away. A lot of time and much $$$ went into these.


http://www.photohost.org/gallery/data/500/2374IMG_2022small.jpg


Todd
It's your stuff and therefore your choice whether or not you want to share the details but if you choose not to then the discussion is over before it can begin. Kinda nullifies the value of the thread if you're not willing to share the details don't you think?

[tpepmeie]

It's your stuff and therefore your choice whether or not you want to share the details but if you choose not to then the discussion is over before it can begin. Kinda nullifies the value of the thread if you're not willing to share the details don't you think?

Not trying to offend anyone. Yes, I paid for these heads, but I don't think it is fair to show the finer details of a professional's work, developed from his years in the trade. I am sure he would consider that his trade secrets. He earns a living that way, so I was just trying to respect that, that's all.

Other than that, I'm happy to talk about the subject (as we did in the other thread), as much as anyone wants to. I love talking about the topic, and have a genuine interest in how this stuff works.

I'll edit the original post to remove the reference to I.P.

Todd

[Locobob]

I enjoy these technical discussions as well. I can certainly respect your concern regarding the person who did the work for you, perhaps you should ask him if he minds the details of his work being discussed here.

[tpepmeie]

Some basic info/observations about the ports: As I said before, they are small...about 35mm for the most part. Not a great deal of taper, but pretty uniform. The taper is provided by the plenum runners, as they are larger at entry before the bifurcation. Shape is not round throughout, and also has to be larger in some spots due to the turns in the tract. Pretty standard stuff for a four-valve, the min csa is before the turn and that dimension was basically set by the casting...could have been even smaller otherwise. A lot of focus was put on the short side radius, as you would expect. Very little if any material was removed from the long-side and bowl. The port shape adn dimensions were determined on the flow bench with a velocity probe. The valve job must be killer, as the low and mid-lift flow is quite strong. 39.5mm valves w/ thin stems and tapered bronze guides.

Also interesting to note that the valve center is offset from the port, as designed by Lotus. Presumably this creates quite a bit of mixture motion in the chamber.

[Polo-1]

just watch which " professional " you choose.

B.K. special
http://i7.photobucket.com/albums/y292/kpie/DSC07909.jpg

Just needs a little silicone to seal up:thumbsdo:

[limey]

B.K. special
:thumbsdo:

Is that as in Burger King or the Bearing King?

Oh *&^%(&^^ it, don't get me wound up!

[Locobob]

.
Also interesting to note that the valve center is offset from the port, as designed by Lotus. Presumably this creates quite a bit of mixture motion in the chamber.

Often referred to as port biasing, my LPE heads were like that, I kept with the theme when I went through them again recently. I'm a bit surprised by how small your runners are given you are building a stroker. It'll be very interesting to see how it does in relation to the current "bigger is better" builds. The relatively smaller runners you are going with are not necessarily new, most of the early LPE builds I've seen are pretty conservative in the porting department too. The chamber shape on the other hand is something I've not seen before on an LT-5, LPE stuck with the clover.

[tpepmeie]

I'm a bit surprised by how small your runners are given you are building a stroker. It'll be very interesting to see how it does in relation to the current "bigger is better" builds. The relatively smaller runners you are going with are not necessarily new, most of the early LPE builds I've seen are pretty conservative in the porting department too.
Conservative in size, yes. However, they move a ton of air, and as much or more as the LPE big valve heads. The housings only lose less than 10 cfm airflow, which is quite good. Took a little extra effort, though...the first pass through resulted in a 20 cfm drop! We're going to test them on Greg's bench too, just to confirm the results and add the plenum to the system.

Todd

[LGAFF]

When you said that the ports were small, I was thinking 34 or so.....my 92 had around 35MM ports and produced decent power(391rw) considering no tune. The 36MM ports I have done have produced power similair to those of 92, but I assumed some benefit on the 92 due to cam timing, as the 92 had lower miles than the other intakes I have ported.

Recently did a 36MM for a 368, wil be interested in results.

[Paul Workman]

Not trying to offend anyone. Yes, I paid for these heads, but I don't think it is fair to show the finer details of a professional's work, developed from his years in the trade. I am sure he would consider that his trade secrets. He earns a living that way, so I was just trying to respect that, that's all.

Todd

Truly fascinating stuff - this porting thing. And, for that reason, like Bob, I feel more than a little frustration with the holding of information. But! As you said, others have paid the dues and are entitled to the data they developed. If you or I wanna experiment w/ our own stuff and publish the results, nobody would say nay to that.

Just what size/shape is best? A wise old sage once said, "Truth is where you find it!" My point is, there is soooo much more to evaluating porting than a "static" flow bench can evaluate. I'm talking about harmonics set up by the opening and closing of the valves; the interruption and reflection of air flow - harmonics in other words - which play an important roll in "internal supercharging". My point is, what looks best on a (static) flow bench is not necessarily what is going to be best in practice. And, for most of us mortal people, the math gets sooo complicated that all we can do is get close, and then experiment and see what trends develop. The proof is in the pudding, in other words, along with what is desired from then end product.

Gotta run. "Mo later!"

P.

[Jagdpanzer]

Todd,
Thanks for sharing with use.
What material did you use and how did you go about making the port molds?

[XfireZ51]

Todd,

Will you be posting air flow numbers when you get them? How will airflow determine or change the cam specs you land(ed) on?

[tpepmeie]

Todd,
Thanks for sharing with use.
What material did you use and how did you go about making the port molds?

US Composites 74-30 liquid urethane. The stuff is dead easy to use... just make sure you mix it very thoroughly. Otherwise you end up with a port full of gelatinous goop which never hardens. ask me how I know. :o

[tpepmeie]

Todd,

Will you be posting air flow numbers when you get them? How will airflow determine or change the cam specs you land(ed) on?

Don't have them in front of me right now. From memory...>340's CFM @ .500 lift. But, of course like others have said, we don't race flow benches!

[tpepmeie]

Here are some good SpeedTalk threads on the topic, if you are interested...

http://speedtalk.com/forum/viewtopic.php?t=16689

http://speedtalk.com/forum/viewtopic.php?t=17340

http://speedtalk.com/forum/viewtopic.php?t=18803

http://speedtalk.com/forum/viewtopic.php?t=11578

http://speedtalk.com/forum/viewtopic.php?t=12924

http://speedtalk.com/forum/viewtopic.php?t=18730

http://speedtalk.com/forum/viewtopic.php?t=14205

If you are so inclined, search for posts by Darin Morgan, Erland Cox, cboggs, and maxracesoftware (Larry Meaux).

Todd

[XfireZ51]

Don't have them in front of me right now. From memory...>340's CFM @ .500 lift. But, of course like others have said, we don't race flow benches!

I was curious about the low lift numbers and the I/E ratio. No question 340cfm at .5" lift is a great number. Is your cam going to be using that high a lift?

[Jagdpanzer]

US Composites 74-30 liquid urethane. The stuff is dead easy to use... just make sure you mix it very thoroughly. Otherwise you end up with a port full of gelatinous goop which never hardens. ask me how I know. :o

Does this stuff set up ridgid or stay flexable?
and how easy are the molds to extract after setting up?

[flyin ryan]

how easy are the molds to extract after setting up?Not hard, use a release agent.

[tpepmeie]

Looks like threads from Sunday didn't come over to the new forum.

Anyway, the heads -small ports and all- flat rocked on another bench and repeated the results seen at RFD. Actually a few cfm better. Amazing results considering only .5mm oversize intake valves.

The housings.... well appear to be a dud. :mad: Lost a ton of airflow and couldn't repeat the previous numbers for some reason, not even close. More work to do for sure. It would be an absolute shame to cork up these heads with weak injector housings.

stay tuned.:thumbsup:

[LGAFF]

The housings.... well appear to be a dud. :mad: Lost a ton of airflow and couldn't repeat the previous numbers for some reason, not even close. More work to do for sure. It would be an absolute shame to cork up these heads with weak injector housings.

stay tuned.:thumbsup:


So are you saying that the 35MM is not enough? Been reading up on Sean Hyland's(Another Damn Canadian) work on Cobra DOHC NA motors, looks like they have 37MM runners on the 5.4s producing 500hp. Cam timing is interesting also. Our intake to exhaust valve ratio seems alittle on the high side in comparison too.

Seems Cobra motors have secondaries also

[Polo-1]

Yes, it looks like they are lost.

For those who did not see, or hear.

Todd's heads out flowed me by a good margin in my book. same bench, same operator.

Todd tiny port vs Kevin Big Dogs

http://i7.photobucket.com/albums/y292/kpie/KP9.jpg

These are one of the biggest ports GVD has done.
http://i7.photobucket.com/albums/y292/kpie/KP2.jpg

[tpepmeie]

So are you saying that the 35MM is not enough?

Dunno. Probably will go bigger at least at the entry and also the injector bosses can be cut down a lot more.

Even the best ported housing is still gonna lose a little. Can only wish we had the next-Gen LT5 setup, with the nice straight shot runners. Or more hood clearance and some individual throttles and trumpets! :mrgreen:

[flyin ryan]

As I said in the 'lost' post's, not to poke my nose into your guys' business, but please, PLEASE don't live & die by 'Dry' bench alone. Todd, your guy (C.B.) didn't do your heads wicked then get stupid on the Injector housings. The 'Dry' flow bench will lie to you if you let it,...Believe it! Just don't want to see you guys, & everyone else out there, get tripped up :neutral:. Put it together, it'll haul the mail ;)

[Paul Workman]

From a scientific point of view, I too would be curious to see what your setup would do "as-is", being that you can always go bigger on the IHs later (but it is harder to add metal once it is gone). In addition to flow characteristics, the resonance frequency (a la rpm vs. torque) will shift upward as the diameter of the Helmholtz tube...er...IH increases.;)

Although Mr Ryan is being cagey ;)- at least on this open forum - I agree there is sooo much more at play that a flow bench does not reveal. It would be very interesting to see some dyno curves with your IHs and then with some slightly bigger (like mine). I'd be willing to lend my IHs/plenum to ya to do just that, but there would be the transition between my 36.xs to your heads' 35s to figure out (epoxy?).

It is always interesting to compare the calculated design to actual. One thing some flow treatments do NOT do is consider is surface area of the intake runners; I'm speaking of programs that only deal with cross sectional area and not consider the barrier zone on the surface of runners. Point being, if it is a dual runner the cross sectional area can be made the same as a single runner, but the surface area (and resonance characteristics too!) are significantly different. There is significant wiggle room if the treatment is overly simplified and in the end what works best...works best (regardless of the model predictions).

As for the "Big Dogs" not flowing as well as Todd's, (assuming all else being equal in the test) there's got to be some turbulence being developed in their design that is creating some kind of standing wave(s) - effectively pinching off the air flow...would be my guess. Wanna really see a reduction? epoxy a flat surface on the knife-edge of the divider in the head, so that the flat surface is no wider than the septum, but perpendicular to the flow. (Same principal - when a big runner couples with a smaller runner w/o any taper in the transition:jawdrop:!)

P.

[flyin ryan]

As for the "Big Dogs" not flowing as well as Todd's, (assuming all else being equal in the test) there's got to be some turbulence being developed in their design that is creating some kind of standing wave(s) - effectively pinching off the air flow...would be my guess. Good post Paul. If the above was/is the case, the flow bench would get very loud, call it dirty air. As far as that goes, can have two ports/heads that 'Dry' flow the exact same, but if one of the two is very loud, it's dirty/turbulant air, & that one will not run with the good 'Clean' one in the car or on the track.

[flyin ryan]

It is always interesting to compare the calculated design to actual.
I always refer to Warren Johnson on this one. He will say, 'When fact's dis-prove theory, believe the fact's & get a new theory!'.

[Pete]

So are you saying that the 35MM is not enough? Been reading up on Sean Hyland's(Another Damn Canadian) work on Cobra DOHC NA motors, looks like they have 37MM runners on the 5.4s producing 500hp. Cam timing is interesting also. Our intake to exhaust valve ratio seems alittle on the high side in comparison too.

Seems Cobra motors have secondaries also

Lee, where is the info
Went to his site couldn't find it.

Pete

[scholtmj]

Speaking of dry flow benches, doesn't Dart wet flow their heads now? I heard they developed wet flow technology but have not heard anything recently. I suppose you would still dry flow the IHs but wet flow the heads.

[flyin ryan]

Speaking of dry flow benches, doesn't Dart wet flow their heads now? I heard they developed wet flow technology but have not heard anything recently. I suppose you would still dry flow the IHs but wet flow the heads.Yes, Richard Maskin had Joe Mondello build them a wet flow bench, I believe it cost around 60K. Flow everything on the wet bench, Everything!, Including IH's. Mixture is going in both directions, like a mini tornado when an engine is running. I 'Hate' Dry benches, personally :cool:.

[tpepmeie]

It would be very interesting to see some dyno curves with your IHs and then with some slightly bigger (like mine). I'd be willing to lend my IHs/plenum to ya to do just that, but there would be the transition between my 36.xs to your heads' 35s to figure out (epoxy?).

That wouldn't work. My heads are neither 35mm, nor round, at that interface. We're not going to get crazy on the housings csa, but we will knock the injector boss way down, and enlarge the entry. Kevin's mono runner is a cool looking piece, and flows very well, but I'm not going that far.

As for the "Big Dogs" not flowing as well as Todd's, (assuming all else being equal in the test) there's got to be some turbulence being developed in their design that is creating some kind of standing wave(s) - effectively pinching off the air flow...would be my guess.

I think it has more to do with my valves, chamber, and short side radius, rather than any particular turbulence in Kevin's port. His heads flow very well.

Todd

[LGAFF]

Pete, I read about it in his book, Sean Hyland also has a website.

http://www.seanhylandmotorsport.com/


http://www.seanhylandmotorsport.com/modular_crate_engines.shtml

1998 DOHC 4.6 with secondaries

http://www.karkraft.com/New%20Parts%201165.jpg

5.4 -GT/Cobra R heads

http://www.karkraft.com/Ford%20GT%20heads2.jpg


Twin Port Head
Dimensions (Intake)
Square Port 32mm x 40mm
Oval Port 36mm x 44mm 1999 & Later 4.6L Tumble Port (Intake)
50mm x 39mm 1998 & Later 5.4L Tumble Port (Intake)
59mm x 39mm
All DOHC Exhaust Ports
48mm x 25mm




http://www.karkraft.com/Ford%20GT%20heads2.jpg

Check Border's or Barnes and Noble for the book.

[Polo-1]

rumor has it, Todd's heads and my intake flowed only 10 cfm less then just my heads alone. :jawdrop:

http://i7.photobucket.com/albums/y292/kpie/DSC08534.jpg

[XfireZ51]

Where's the choke point? Is it throttle body or plenum volume?

[Polo-1]

:dontknow:

2 38mm balls fall all the way down into the heads.

TB is 2 64 mm blades plus over sized primary.
http://i7.photobucket.com/albums/y292/kpie/2010-01-03034a.jpg

[LGAFF]

Not sure how many of these apply to the DOHC cam engines, but..

http://www.wallaceracing.com/Calculators.htm