Looking for a few tips on porting 351c 4v heads

[cjperformance]

Well that got the heat off of those darn aussies that copied the A3's !

[groberts101]

There is misinformation on forums about what aussie/3v heads really are so just wanted to make it clear for those that dont know that the aussie "3V" head is basicly a Copy of the old American SVO head, as was the aussie 3V/4V parker Copy intake which was Originaly made by Roush and Edelbrock years before for the American SVO head.

Yes there is.. and it keeps getting perpetuated even further along as every new day goes by. And not to try and poke holes or start a whole new "who copied what.. and when" debate about the intakes for this engine platform.. but that is most certainly incorrect info about that specific manifold being copied by Parker. I know this for fact because I've personally ported that Parker intake and can tell you without a doubt that the MS/Roush manifold is no where near the same. Well.. aside from being a taller single-4 spider type design, is all. The Parker's taller.. runners are taller/thinner and have bigger port taper from start to finish.. and CSA is also bigger without even getting into the carb pad and plenum design aspects. Much closer to a newer Super Vic type design than that MS/Roush design you posted above.

As for who copied what head?.. well.. don't rightly know for sure how that timeline went but I do know that it get's pretty damned tricky to make something symmetrically ported that's entirely new for a 90° V type motor without copying at least some or many aspects of a previous design. Probably have to go back a fair bit further than that old mystery motor to find it too. So, technically speaking.. everything relating to the 2 valve stuff is just a newer copy of something old.

[cjperformance]

Lol, geez i recon the person who started all this copying was the 'second' 'inventor' of the wheel !
But yes, it was definetly volvo that started it all !
I think that a copy is exactly that, a pretty much exact replica of another peoduct that is branded by another person/company as their own with no r&d work.
When someone like Parker (just using this name as an example) sees a single plane intake for example and thinks , cool idea but i can do it better or differently and then puts in the effort to 'improve' or 'change substantially' the basic layout of the item that spurred the idea, then im nkt so sure you can label this as a 'copy'.

[Bos's5.0]

I met a person who swears every engine spec ever measured was sourced from a Mopar.

[RL]

Yeah, the Parker is pretty different internally to the Roush.

The SVO and Roush are racing equipment, so are not really suitable for the street, so the 3V and Parker are different internally to suit a different application.

Just because the externals look close doesn't mean it's just a direct copy. Some people copy, but why copy something when you know how to make it better, that's more an evolution.

You can get heads with many different port runner volumes, so is the one close to the cc's of and earlier head a copy, and the others not a copies.

I think the 3V's are more a copy of the original iron head, but with a shrunken down Prostock port - the guy helping development was a Prostock engine builder -, so the the port could even be a Mopar variant.

It's the ports and chamber that should be copyrighted, because the external part of the head is just a locating device.

[cjperformance]

I met a person who swears every engine spec ever measured was sourced from a Mopar.

Yeah I've met some kooky Mopar dudes before too
Ive met kooky dudes from all parks of life but I have to say i have met some quite odd Mopar fans over the years!

[cjperformance]

Yeah, the Parker is pretty different internally to the Roush.

The SVO and Roush are racing equipment, so are not really suitable for the street, so the 3V and Parker are different internally to suit a different application.

Just because the externals look close doesn't mean it's just a direct copy. Some people copy, but why copy something when you know how to make it better, that's more an evolution.

You can get heads with many different port runner volumes, so is the one close to the cc's of and earlier head a copy, and the others not a copies.

I think the 3V's are more a copy of the original iron head, but with a shrunken down Prostock port - the guy helping development was a Prostock engine builder -, so the the port could even be a Mopar variant.

It's the ports and chamber that should be copyrighted, because the external part of the head is just a locating device.

X2
Well said

[RL]

not an issue, only need to cut a min 1/8" wide flat spot for alum plate to sit on, high temp fillers like Pyro Putty can also used in left over old exh port filling/sealing it up under the hi-port plate.

Look at the 3V exh, it isn't raised, yet it's a better head.

also forgot to mention that yes it is raised, there is only just over a 1/4" difference in top of exh port heights
between the American original hi-port mod and my Avg aussie "3V" Copy.

btw, that is a 2" diameter pipe sitting over the Avenger exh port.

It really needs to be compared it to an old iron 2V - just scaling cjperformance picture, because I don't have a head with me at the moment, the 2V is approx 90mm to the top of the port, the same as in the pic -.

I suppose they were hi-ports compared to 50's stuff, but the term Hi-port used with the old 4V isn't actually a high port, at least not by today's standards, it's just a term to discern the modification. If you look at some modern exh ports they are straight and vertical, with the turn in the pipe.

I''ll give you my reasoning why I don't think the hi-port is a great modification, using an actual example.
The std irov 2V exh port can be ported to 225cfm.
2 - 4V hi-ports came in that were done by someone else and one flowed 221cfm(worse), and one flowed 231cfm(slightly more).
Knowing this I had to make mine extreme, hence why mine is so high, and I got 253cfm@0.700" - it's probably something like ½" higher than your old hi-port mod head -.
Conclusion, a lot of work for a small gain.

[/quote]

[Bos's5.0]

↑ ↑ ↑↑↑.........That is awesome.

[cjperformance]

And then you need the room to make pipes that will complement the hiport mod !!

[cjperformance]

Lol, geez i recon the person who started all this copying was the 'second' 'inventor' of the wheel ! .

hey we all know you aussies Copyed that from the American Original too .

I met a person who swears every engine spec ever measured was sourced from a Mopar.

Yeah I've met some kooky Mopar dudes before too
Ive met kooky dudes from all parks of life but I have to say i have met some quite odd Mopar fans over the years!

next to the cheavy guys some mopar guys are Way stranger , i got personal experience .

Hey that Flint mobile needs a hiport 4V conversion with 6' long Munster zoomies!

[RL]

And then you need the room to make pipes that will complement the hiport mod !!

Yeah. It goes in a Cortina so you can't turn the pipes down, you have to go up and around and down so that it exists through the inner guard near the firewall.

[RL]

no, the "3V" aussie Copy exh port must be compared to the old SVO head as the old iron 2V head exh port height is no higher than the iron 4V, the aussie "3V" copy and A3-b-c are much closer to each other.

The A3 hadn't been invented, so how can it be called a hi-port if it wasn't higher than the iron heads. 3V 90mm, iron head 90mm, not much difference.

It looks like SVO made an alum copy of the modified 4V, but changed the ports and made them better - an evolution, which is the same as a 3V. Looks like the SVO is a copy too.

I think your picture say it all, because those ports don't look like each other at all. Get some port molding compound, and it will open up your world.
SVO

3V

also the 4V cc Hi-port mod was done by Every American P/S racer that was serious about winning as FORD them selfs stated it was good/dynoed for a MINIMUM of 20+HP (heard some getting over 30+HP), 4V cc was the TOP DOG p/s cleveland head so mod is more than a small gain, NONE of them were waisting time or money with the inferior 2V head.

20 hp on a 900hp engine, so what should I expect on a pump gas street engine, maybe 10hp - told you it wasn't much -.

Pump gas 4V intake filled no hi-port exh, we get 601hp
Pump gas 2V ported only, we get 585hp.
If you do the development, the 2V isn't that bad and requires less mods.

the Hi-port mod may not be for every build but it is still a great mod for some guys that want to take there old iron 4V heads to the next level.

The guy is a street guy, so if he did the mod it would be more for show than go, because it's a lot of work for only a small gain.

[RL]

You do know by your criteria you have just argued that every US aftermarket head manufacturer copies.

Boo on you for calling Roush a copier, because we all know now that you can't make a different head for the same application without it being labelled a copy.

You have also backed me up by saying that the 3V head has a lower port, and because it can still win an EMC it kind of proves that hi-ports aren't that necessary.

Gee I think you guys better lock up that Kaase for treason, because he used an known copy rather than the good old US SVO A3 copy of a 4V hi-port.

4V 601hp, 2V 585hp, doesn't sound like a dud at all, and it has no tricky mods either. Maybe you need to work harder.

[Bos's5.0]

4V 601hp, 2V 585hp,

Any chance you have a port picture of a 2V fully ported that you can release? I always thought they were duds because all I ever saw were people do a bunch of work and end up with 230cfm intake ports.