Read CW25's blow through thread with a lot of interest, but of course EFI creates a bit of a different distribution challenge. What's the thinking on the best intake to convert to efi for the b block for street use? Strong low end, good mpg (relatively speaking), even distribution are all more important than peak hp.

If I were doing a carb'ed motor I'd be using the rpm perf. hands down, especially after reading Hot Rod's intake shoot out the last 2 months. I've long used a Holley SD thinking it was a good HP piece with lower hood clearance, their tests validated what my buttometer had always thought about the low end on that thing!

*edit* Didn't say that I've been looking at (with a talented, proven DIYer friend in Minn) making adaptors for an LT1 intake onto the 383. While it's narrower and the distance between the ports is about 1" shorter, it's really not a bad fit (I bought one off ebay so I could mock it up on a 383). An OEM designed (relatively) HP EFI intake seemed like a decent idea over a converted carb intake. Any thoughts on that route? Only major issue is that I have to spend money to convert the a/c to an underslung sanden compressor, as the big v-twin is very much in the way of the LT1.

 

Here, mull over this post - it pertains greatly to this question.

https://www.theturboforums.com/smf/index.php?topic=48763.0

Cliff notes: here's the post that ended it, which I thought was great:

 

I would agree, the most likely outcome is a cylinder or 2 that are rich. This can cause fouling issues, and can effect mpg (important for me).
I have the seq. system, so I can trim a cylinder, but I think only over the entire rpm range, which may or may not be appropriate. As long as a manifold doesn't cause actual fouling, I'm probably not picky enough to experience much difference, but:

Booster (Jim) has tried several intakes on his 340 over the years, both carbed and with the FAST, and has found deviations significant enough that he would rank different manifolds as better for power vs. better on the street/distribution/etc.

His great R&D on smallblocks does me no good however I was hoping someone on here had been as much of a Mad Scientist with BB pieces.

 

The most prolific BB (and possibly EFI) scientist I've seen on this forum has been TRENDZ, hands down. Although his last combination was extra-wild, he rose through the ranks like everyone else, with regular parts. I'm sure he can "sprinkle" some knowledge on this thread.

To be honest, I was so excited about having my car back driving around that I haven't even pulled one plug to look at it. Real plug reading happens at the track, immediately after a pull anyway, right? I guess I can offer some evaluation of an old eBay B-performer (I think that's what it is...I milled the name off so long ago, hahah) when it is warm again.

In addition to CW's reviews, I think another great place to turn to is the BT Carb guys, who are 100% at the mercy of their intake's distribution for fueling. Many of the successful SBC's (perhaps relevant here due to the same firing order as us, and thus the old "5-7" stealing theories) are using giant single-planes with great results. I think.

 

My opinion would depend on what you want out of the engine. My personal thoughts were always geared toward most power. I would have never considered a dual plane intake, until reading CW's back to back "test". My thinking was, and still is, with boost, the charge density is higher, and denser air is harder to "bend". This thinking was the reason that I chose to use a tunnel ram for my intake. The tunnel ram had long straight runners. All dual plane intakes I've ever seen have at least one 90 degree turn in each runner, to help lengthen the runner . The sharp turn in the runners is no big deal for flow in a situation where there are negative pressures(vacuum) in the intake(much less dense, easier to bend). This would account for the improved "out of boost" response, but I'd bet a dollar that it hurts power more and more as boost levels get higher. I never had complaints about throttle response or torque with any of my combos, but thats with efi. You speak of sub 500hp numbers, at that level, you could smash a stock intake flat, and still make the power if you add some boost. When you decide to make some real power, use an intake with the straightest runners you can find.
I'll attach a dyno graph with the weiand tunnel ram in the picture. I haven't used a dual plane since the old old days when I had a single sided turbo system that didn't work all that well. I was drawn to the tunnel ram when I realized it had no heat cross over. y

#ad


#ad

 

I really wish I had a dyno to test thses intakes back to back but I don't have one in town. Nearest one around I know of is 300 miles away. I am sure it gives up a little upper RPM power but it isn't even noticable to make me swap back to a single. The off boost driving is well worth it. It all really depends on what you want. Maybe when my S400 with 1.0 A/R hsg goes on I will want the single back on but I doubt it. The nice thing about the RPM intake is that it is a true high rise and has gentle turns unlike the stocker. I do agree completely that if someone is trying to get all the hp they can a dual plane isn't the place to look. Best street maners dual plane. Hp is the most concern single plane.

 

Re: Best B block intake for EFI conversion (for street response and distribution

I had similar concerns when choosing an intake for my first efi/forced-induction setup. People who know me know that I have a very heavy bias towards the low end of the rpm scale, throttle response, idle quality, mpg, etc. I chose to modify an Edelbrock Performer RPM for injectors. To achieve super crisp tip-in throttle response requires higher velocities in the column of air moving through the intake runner, which can be achieved with the longer runners as found in dual plane intakes like the Performer RPM. As noted, this is not the best intake setup to choose if your bias is towards the higher end or max power. But if your only running moderate boost levels and care more about driveability then you could do worse. FWIW, my car averaged 18.5 mpg highway last year with this setup in a 4,000 lb car with 3.54 gear and 5-speed trans and still managed to make 840 rwhp on a 500 c.i. with only 9 psi boost and a 224 @ .050 cam w/114 LSA, but that's not very impressive to me compared next to the total docility of the combo which idled and ran smoother than a stock 440, with the hood shut nobody had a clue what was going on. The dual plane also allowed everything to fit under the stock hood without having to fab a custom low profile intake. As you can see, it's just as TRNDZ says, it's all about what you want out of the engine and where your bias is.

 

I remember reading the thread about your(CW25) intake swap, and I was suprized about how much better you said it felt. I'm not doubting there was an improvement, anytime you can get a "seat of the pants" feel, there is no doubt that you moved in the right direction. My point is, a dual planes life purpouse is to improve torque. Did you see my torque peak RPM? Would you want more torque than my tunnel ram?

 

TRNDZ, with the way the tunnel rams tested in Hot Rods article, I can understand what you were saying. I think it was the Weiand that was the real winner- a torque monster that would not have been expected. IIRC it out torqued the Holley SD, the torker, the victor, the M1, the early 60's low rise dual quad, and all the other tunnel rams. If I was willing to put a scoop on my car, that article alone would make me seriously consider that intake.

It's the same prinical, however, that makes the LT1 so interesting to me.

 

Edelbrock has the Victor RB manifold from their EFI kit available separately now. It's listed as a 3500-7500 RPM piece, but boost would surely alter that range.
http://store.summitracing.com/partd...908395 4294908110 4294840062 115&autoview=sku

I haven't seen any B engine manifolds available yet for port EFI. You have to convert them.

As for the LT1 intake, that's an interesting idea. During my early EFI research I got a set of smallblock Chevy intake gaskets (for evaluating fuel rail options) and remember that the port spacing was pretty close except the B-RB Mopar was about 1/2-1" longer between the siamesed ports. I'm assuming you're thinking of adapter plates of some sort? Those might not be too hard to make on a CNC machine, plus now you've added the option of common fuel rails and throttle body that the LT1 upgrade guys are getting rid of.

 

furious70:

Looked at some pics of the LT1 manifolds.
How does the F-R spacing of the bolts holes compare to Mopar?
Being that the LT1 has vertical bolts do any of them fall on top of the Mopar holes or are they all in different locations?
How thick will the spacer adapters need to be?
Will teh adapters have parallel surfaces or angled?
Can the adapters bolt to teh Mopar heads and then the LTI bolt to the adapters like a carb adapter plate?

Dues to the port spacing difference the injectors won't be pointing directly at the intake valve but I'm thinking the low-cost benefits associated with this package will outweigh that.

 

Exactly FF. The ports themselves are all the same, as you say, the space between is just shorter, and of course the LT1 is narrower. And I bought the intake, rails, regulator (not useable), and TB (with sensors) for a $125 shipped.

The 383 victor has the bosses I think, Edelbrock tech told me to buy that vs. convert any of their old intakes. Said they did testing to prove with EFI the runner/plenum volume didn't matter. But hearing him talk, it sounded like he was talking about an all out motor, not a street motor.

The spacers can be as much as 6-8" if you wanted them to be and still fit under the hood. I was thinking about 2" I think, that was enought to clear the distributor. The front and rear of the LT1 have to be milled off, the valley area is a lot longer than I thought it would be. Like I said above too, the fwd facing TB means the v twin has to go, not a cheap proposision, but the sanden compressor is more efficient and kicks in and out unlike the rv2, so there should be some mpg savings there.

The best I could measure the angles of the intakes (and head surfaces) they are parallel, which makes things a lot easier.

Have not looked at where all the bolts lie, but I would assume it's probable that they'll have to bolt to one side or the other, be tightened down, then bolt to the other side as you ellude to.

Also hadn't thought about the hiding of the valve, but at the levels I'm talking about I'm not sure that will be an issue.

 

found the HR articles:

The Weiand hi ram with a single top has almost identical #'s to the rpm perf on both the mild and wild 383's tested.

On the wild motor the MP and offy TR's were 30ft#'s off the Weiand, and the Weiand actually made 24ft# more peak 100rpm LOWER than the rpm pref.

On the mild motor The M1 was down 8ft# peak and 12ft# at 3000rpm compared to the rpm perf while both were within 4hp peak of each other.

I see that helping TRNDZ nasty tq curve if you're running the Weiand, and some support for cw25's buttometer. What would be interesting is to try the TR on cw25's motor now too, tho the hat or plenum alterations may change the results.

 

Furious 70:

I put an LT1 intake on my 'to get' list (there's a super-cheap junkyard in town), and I've run the idea past my one of my buddies that has good ideas and insight. I'll see what thoughts he has, perhaps you've stumbled onto a goldmine of an idea.

The fact that the LT1 intake bolts are vertical would allow studs to be used and eliminate stripping of threads in the adapter plates, which is nice also.

 

I can't take credit for the idea, an unamed source tipped me off to the idea a year ago or so.

 

looked at the LT1 over the weekend again. Looks like the spacers would need to be at least 2.25-2.5" tall to clear the distributor. If a guy was using eDist (I'm not), it could be lower. The cost of making spacers that tall, cost of a/c conversion, and potential that making the runners that much longer may significantly effect the OEM design make me wonder if it's worth considering further.

 

Sorry to hear that there's a hurdle there, but you saved me $$ from buying an LT1 intake to try myself. However, the height of the spacer might now allow space to machine the injector boss into it, thereby putting it closer to the valve again. But then the original bosses would have to be welded up, and this kinda defeats some of the benefits of using this manifold...

I looked over the weekend and there is no way an injector could be pointed at the back of the intake valve as theoretically is desired. The injector would have to lay back about 30° and toward each other in the siamesed pairs. Even then it is a curved port to the valve, both to the side and downward.

Here's what I've been doing, it's nearly complete. One of the bosses is a little crooked, but the O-ring seal is probably still functional (the injectors are tough to get into these fittings so it should seal).

Need to hog the adapterplate out a little more for better transitions, grind the fittings down in the intake ports, and epoxy one of the fittings that stripped when I was tapping it (and in the blink of an eye). Also want to hook it up and see how an injector sprays out of that fitting (should probably do that first).

Overall I think I'd prefer the flow channel possibilities of a larger/aftermarket Ford 5.0 TB on a 4-V intake, but I haven't figured out how to easily install an OEM Mopar air cleaner on one, which is the look I want - a nice large aircleaner to hide the injection stuff if possible. This Magnum TB fits a 5 1/8" aircleaner neck perfectly if an offset tie-down stud is used.

Here's a little bit of thread on this:
http://www.msefi.com/viewtopic.php?t=25232&sid=ae39975def6020c8bba9db1b818ab6e3

And in pic #3 you can see a small portion of one of my prizes, a super-rare 1959 B-engine factory EFI manifold. EFI was tried in '58 on the RB engines (with limited success), and this manifold was reportedly going to be used in '59 on teh B engine but the project got cancelled. Unfortunately the bosses in this manifold are further apart than the Edelbrock fuel rails and the threads are only slightly larger than the botton of an injector O-ring. I could probably get some custom fittings made but I think that the spray pattern would be shrouded by the manifold too much. And as anyone can appreciate, I sure don't want to modify this manifold!!!

#ad


#ad


#ad

 

I knew I should have shut up and just sold you my LT1

Nice score on the efi intake, even if it's not useable. I've only ever seen one on ebay, never in person.

The 2bbl and magnum TB is an interesting idea. Do none of the aftermarket 4bbl TB's fit the air cleaner (not speaking of the outrageous cost of them)?

 

I got this intake off Ebay about 2 years ago, so maybe this is the one you saw.

I believe the aftermarket 4-barrel TBs are 5 1/8" neck, but I was mostly trying to avoid the $6-800 hit so I started messing with the Magnum TB and the 2-V intake. Plus, I had both of them laying around and a 2-V manifold isn't worth 2 smashed flies anyway. So far I'm down a piece of aluminum (also on-hand), about $30 for the fittings and 6-8 hours of experimentation.

There is an adapter available here, I need to contact these guys and see if they'll sell it separately. I don't know if it would cause a hood clearance problem, though.

If I get desperate to get running EFI quickly I'll drop coin on one of these:
http://www.straightline-perf.com/categories/induction-components/products/product-219.html

But for long-term plans I'd like to figure out a good method to convert iron manifolds and OEM TBs, which are available super cheap, sometimes free. I've got 2 cars I want to convert, and if I can find a combination that I can convert one for $750 or so it'll free up $$ for other things.

 

FYI here is a cheaper throttle body.
http://www.auto-nomics.com/cgi-bin/showresults?a=detail&part=12168-001