A couple of different mockups today

[My427stang]

I am building two 461s, one is a CJ replica and will look stock, the other an EFI.  All the block and head machining was done, so I mocked them up to see what I had to do for machine work to the intakes.  The ironic part is that the one that will likely make the most power, looks the most sedate

The CJ will be a stout all iron 10.5:1 hyd roller motor, low 240's duration, 300 cfm CJ heads, 2.15/1.70 valves, and soon to have some nice work done on the iron intake
The EFI motor is an all iron 9.7:1, 230/236 hyd flat tappet, 280-ish cfm truck heads that are opened up pretty good, 2.09/1.67 valves, and a little rubbing on the Victor EFI intake

As I expected, both intakes fit great, the heads and blocks weren't cut too much, and it should work out well.  Now it's just plenum work on the CJ intake and a little rubbing on both

They will move a bit more slowly than I'd like as I wait for parts and sneak some time off but thought you'd like to see the contrast between the two

[blykins]

I think I'm more fond of the CJ look-alike.  I love stock-appearing engines that perform.

[Heo]

I think I'm more fond of the CJ look-alike.  I love stock-appearing engines that perform.

Im on that same train....  What you got there,  Ohhh just a well tuned 390

[My427stang]

I like them all.  The CJ will be dressed in 68.5 garb when done, Stock filter with ram air lid, and chrome GT valve covers, it'll certainly be pretty.

No idea yet on the EFI, likely Lemans valve covers or tall chrome Pentroofs and a 14 inch Ford repop

[My427stang]

Here's a little more on the CJ, we went with a head that was done in a couple steps, even could be considered backwards, but we had to play what we were dealt

These are C8OE-N CJ castings, we had them initially done by one guy that misinterpreted what the owner wanted and elected not to do any porting.  In his defense, he did a very nice job on machine work and a good valve job, bowl blend, and 2.15/1.70 11/32 valves.  However, the heads didn't pull the numbers we needed.  Of course flow isn't everything, but this is a factory 4.30 gear car, already undercammed as a stock CJ and we added 30+ cubes.

So we gave Lance Smith a try, he runs Craft Racing since Keith sold off and he does CnC programs for iron heads, only one I know of.  He was able to match all the chambers, unshroud the valves, and work the port to flow over 300 cfm.  You'll see a cut to the floor, but it's misleading, he didn't change the entry significantly, but did work the short side and the roof.  I cc'd the intake ports and chambers and came up with 158-160, so not a lot of cutting, and a big 83 cc chamber, which makes sense with the unshrouding and valves.

Some pics below:

You can see how he dipped into the quench pad and opened up around the spark plug.  I hate giving up quench surface, and don't love a big chamber, but given it will be .041 quench with a flat top,  and we are watching compression and cam choice, it should work well.



The exhaust port came out nice, Just a note, the exhaust gasket surface is not this ugly in person, the camera makes it look rusty, it's in decent shape



The intake port will likely work well too, although I was surprised to see a small cut on the bottom.  Also, those dirty areas are areas the CNC did not cut.  I probably will hit them with a little wire brush to make them look the same color, but they aren't doing anything and are not even really noticeable below the CnC surface by touch other than being a different texture



We also cut for beehives, and used 11/32 valves although not certain if I will go standard springs with Ti retainers, or beehives, they are cut for spring cups and .531 seals now

[Drew Pojedinec]

The CJ one needs the 4609 I just finished

[My427stang]

This one actually has an AED rebuilt correct 68.5 CJ carb, I will go out and check numbers later.

I would have pushed him to you but it was a while ago and he is from Richmond and has a relationship with them.

I honestly would prefer a bigger carb, but it'll do just fine.

[jayb]

I like the EFI engine better.  Much better under-hood appeal, and it will be more tunable.  But that manifold is not a great match to the heads, cam and compression of that engine.  Seems like it would have been better with a Performer RPM, given the rest of the components...

[My427stang]

I like the EFI engine better.  Much better under-hood appeal, and it will be more tunable.  But that manifold is not a great match to the heads, cam and compression of that engine.  Seems like it would have been better with a Performer RPM, given the rest of the components...

Thanks Jay, it's a kit, and as such is much easier to try over a purpose built RPM intake, and as you said, it has a ton of features over a throttle body setup.  Not to mention, it's a bit of a public review for the Edelbrock Pro flo 4 kit, as I understand I am the first guy to jump, and for 1850 bucks or less if you shop around, it's worth trying

That being said, I do expect good things,  my 489 is very happy chugging along at 1400-1600 RPM with a similar intake (not the same, there seems to be some changes to the casting in the last 10 years).  That engine gained everywhere with the EFI over the carbed ported RPM, including dropping the idle 200 rpm with not other changes.  I can't claim the manifold itself was responsible for the gains, because there is so much more to the port injection and computer controlled ignition, but that one did so much better everywhere, I am OK with this. 

Now, if Edelbrock sold a port-injected EFI RPM, I'd likely have tried it on this one for more runner length, but the option isn't there, my hunch is the dry manifold and an injector feeding a sub 140cc 280 cfm port will keep the fuel where it's supposed to be

************ Jay, on edit, I went back to your book, and just for the people concerned with the single plane intakes in general.  On your 390 stroker, the ported Victor and RPM were within 5 peak HP (adv Victor) equal on peak torque, average hp the Victor was down 1 or 2, and it was a wash on avg torque. That was an engine that had to deal with fuel in suspension and more reversion.  It will certainly be an interesting test.  I was going to dyno it with a carb and Duraspark, but might have to build an EFI board to bring with me to show what it really does on the pump

[Drew Pojedinec]

This one actually has an AED rebuilt correct 68.5 CJ carb, I will go out and check numbers later.
I honestly would prefer a bigger carb, but it'll do just fine.

AED is awesome.  and Yeah, bigger than stock would be nice given the cubes.  Either way, looks super cool.

[jayb]

Ross, I'm sure the Victor will work, and I guess that it depends on where in the RPM band the engine will be used.  If it is about a 500 HP engine then comparing it to the 390 stroker dyno mule in my book would be a good reference.  On that engine at 3500 RPM, the Performer RPM makes 507.6 foot pounds of torque, but the Victor only makes 469.2, with both manifolds in as cast condition (see the data in the appendix of my book).  That's a big (almost 40 foot-pounds) difference right in the middle of the power band, and was the reason for my comment.  Now, if the engine is going to have a 4500 stall converter, then the Victor would obviously be better, because it makes a lot more power up top.  But below 4500 RPM, the Performer RPM is a much better manifold.  So I guess it depends on where you want to make the power.  For an engine with cast iron heads, I'm still thinking the Performer RPM would have been a better choice.  On the other hand, the Victor is set up and ready to go for EFI, so I can see why you went that way...

[My427stang]

Ross, I'm sure the Victor will work, and I guess that it depends on where in the RPM band the engine will be used.  If it is about a 500 HP engine then comparing it to the 390 stroker dyno mule in my book would be a good reference.  On that engine at 3500 RPM, the Performer RPM makes 507.6 foot pounds of torque, but the Victor only makes 469.2, with both manifolds in as cast condition (see the data in the appendix of my book).  That's a big (almost 40 foot-pounds) difference right in the middle of the power band, and was the reason for my comment.  Now, if the engine is going to have a 4500 stall converter, then the Victor would obviously be better, because it makes a lot more power up top.  But below 4500 RPM, the Performer RPM is a much better manifold.  So I guess it depends on where you want to make the power.  For an engine with cast iron heads, I'm still thinking the Performer RPM would have been a better choice.  On the other hand, the Victor is set up and ready to go for EFI, so I can see why you went that way...

Jay I understand, and I think we are on the same page.  The engine should sneak up on 500 hp, but not likely above, and by no means is it a drag engine.  However, the Victor is not only set up for EFI, it's a full kit which includes an ECM controlled distributor, intake, injectors, rails, TB, all wiring, ECM, even medium riser intake gaskets and Bluetooth equipped for programming AND a tablet which allows programming and a gauge package if desired to be mounted on the dash.  Depending how it works and how adjustable, this could be a screaming deal.  Even if you bought this kit without the tablet (1750-ish) and tossed the ECM for a Megaquirt, it'd still be a decent value.

I do agree though, given the street use of the kit, the same kit with a factory modified RPM may have been a big seller.  Maybe that is why nobody is biting, these kits have been around a long while in various forms and Edelbrock continues to improve the programming

Regardless, I think the rest of the parts matter too.  Injecting at the intake entry versus a carb, a small fast port with a custom cam pulling hard on the intake through the usable range and reasonable overlap, all should all make it pretty happy with 461 inches even before I bring in the better timing control .  Looking at how the ports line up and the fact that overall volume is less or comparable to the RPM, the only downside is runner length and plenum size, but the latter doesn't have fuel in it.  We'll see

I know you aren't taking pot shots and you have a lot of EFI experience,  this should be a fun one as you pointed out initially

I hope that I can adjust injector timing and slope, we'll see, I have had incredible changes in low end / mid range when I program the injectors to fire based on cam events, my guess is I won't be able to, but we'll see if Edelbrock gave me the option soon enough

[My427stang]

The CJ will in and of itself be an odd one too.

I am sort of treating it as a combination restrictor plate and vacuum rule build although neither of those really apply.  The car is a 68.5 CJ 4.30 geared car WITH power brakes and no option for vacuum cans or pumps or otherwise departing from the stock configuration

Working through that one by trying to get as much airflow as I can without making a big lazy port, spreading the centers on the cam and bringing ICL early enough to keep vacuum up with a hyd roller while still allowing it to eat to feed the steep gear and as much compression as it can handle and be happy on the street.

Shooting for a 6000-6100 rpm shift point out of it with the ability to hang in a bit longer, we'll see

[Joey120373]

. I like the EFI engine better.  Much better under-hood appeal, and it will be more tunable.  But that manifold is not a great match to the heads, cam and compression of that engine.  Seems like it would have been better with a Performer RPM, given the rest of the components...

Jay, I agree 100% . I understand the single plane is much easier to modify for port injection,but i really wish Edelbrock would offer a modified version of the RPM manifold for EFI use. It would be a better option for most users.

A good Friend of mine was modifying a 385 RPM for TPI, but the guy who welded the bungs in basically ruined his brand new manifold. Pretty sad really.

Ross, Those CNC ported stock heads are one of the coolest things i have seen, very cool of Craft to offer that service. Very cool builds you have there.

[427LX]

I am building two 461s, one is a CJ replica and will look stock, the other an EFI.  All the block and head machining was done, so I mocked them up to see what I had to do for machine work to the intakes.  The ironic part is that the one that will likely make the most power, looks the most sedate

The CJ will be a stout all iron 10.5:1 hyd roller motor, low 240's duration, 300 cfm CJ heads, 2.15/1.70 valves, and soon to have some nice work done on the iron intake
The EFI motor is an all iron 9.7:1, 230/236 hyd flat tappet, 280-ish cfm truck heads that are opened up pretty good, 2.09/1.67 valves, and a little rubbing on the Victor EFI intake

As I expected, both intakes fit great, the heads and blocks weren't cut too much, and it should work out well.  Now it's just plenum work on the CJ intake and a little rubbing on both

They will move a bit more slowly than I'd like as I wait for parts and sneak some time off but thought you'd like to see the contrast between the two

Curious on the CJ intake... for a bit more power is a 4 hole spacer the way to go on those type manifolds?

Both of your builds sound great!