Which type of induction system?

[AzCoupe]

First, I am having two different cylinder heads designed, a 2V style, and an all out XF style.
The 2V (4V) will go into production first as it will be the most popular using existing
header designs and a four barrel manifold, as well as an optional triple webber intake.
The crossflow will come later, sometime next year, and will cost quite a bit more.
Especially when considering some of the induction options.

I've been looking at the various types of induction that could be used, and there are a lot
of options. So I'm wondering what you guys would prefer. The crossflow head will be
designed around the induction system for optimum performance. Turbo'd, Supercharged,
EFI, TBI, MPFI, N/A, or a combination?

Here's your chance for some input, so take advantage of it while it's there. They are
starting work on the crossflow design in a couple weeks and I need to let them know by then.

Here's some I've been looking into, but certainly not limited to. Obviously, some are top
end items that would be to expensive for most. They are just food for thought. Most could
be used on the 2V (4V) head too. I've already made a deal with a supplier for the triple TBI
set up and will be displaying it (turbo'd) on the motor I'm setting up for my SEMA display.

HOLLEY 2V&4V CARBS - N/A and/or boosted Probably the most popular and cheapest.

WEBBER INDUCTION - N/A and/or boosted I like this due to the low profile, which allows more room for better intake runner design.

HOLLEY 950 COMMANDER SYSTEMS - TBI or MPFI

TWM INDUCTION - TBI This is nice because hood clearance issuse are totally resolved, but they are expensive. Would provide a straight shot into the ports for better flow.

REDLINE TBI SYSTEMS - TBI Could be used with a 90* adapter to solve hood clearance.

 

[CoupeBoy]

My vote goes for a carburated 4bbl and here's why. Like some of the slant six MPFI conversions you could make a MPFI spacer/adapter to wedge between the intake and head if there is enough clearance near
the shock tower or have the intake cast with spots that are easily drilled for EFI or NOS. You could use an adapter to put on a 1bbl, 2bbl, or TBI.

I am persistantly poor and if I could afford the head I would not have funding left over for a EFI setup that would be adequate to bolt on and I do not forsee myself having the time to build a megasquirt for the DIY path and I have been looking for a mid 80's GM to get the V6 EFI from but they are harder to find then you would imagine.

The parts of your original question that got me thinking is why would the designer need to know what induction method we would be using? Would the head (runners/combustion chambers) be made differently? ie BB6 240head vs 300 head vs 300EFI head? Or does he need to know so that you can build an intake that allows adequate room above the carb/TB location? ie do I need space for an air cleaner or do i need space for a turbo carb hat?

Wouldnt he also be concerned with desired CR? That way he knows what size to make the CC or how much meat to put in the headgasket mounting area so we can mill the head to meet our requirements?

hopefully some our more technical members will some input on this also,
-ron

 

[XFlow_Fairlane]

I say a dual purpose 4bbl intake. have bosses cast in it for injectors and fuel rail mounting. would basicly be free to have added and would just have to charge extra if someone wanted them machined (they could also be used on a port n2o injection setup) killer would also be if you could source a factory cable setup with bracket and have the boss for that added too. I guess the carb would have to sit backwards on the intake though for that really.

 

[hasa68mustang]

I would like the 4v design, Would be easy to set up and no fancy pants computer mumbo jumbo on my car... I like to keep things simple... no offence to Brians car and such.... I would like to get a nice cheap head for I get payed minimum wage and have to pay for insurance and gas and all other expences with what I make... and Mikethanks for your help so far...I finally beat a car, a friend who make sfun of how slow my car was and when I passed him he wasnt happy... and if it kept all the same exhaust ports and such so we could use our existing headers for turbos and such that would be great!

 

[Anonymous]

Mike,

Make mine a 4V too! Dont know if a mechanical secondary 390 cfm would be better or a 600 cfm vacuum secondary though :

Later,

Doug

 

[wsa111]

Mike, I think your best seller would be a holley 390 vacuum secondary carb on a 4 barrel designed manifold.

The other option would be a turbo setup from exhaust to intake.

That would cover the mild to the wild.

The turbo setup could be engineered as a blow through using a holley carb setup.

Lets here it guys, either rest or speak your peace. William

 

[AzCoupe]

I think you are all missing the point of my question.

What you all suggest, is what is intended for the 2V/4V head. It will have a specifically designed 4V intake to match the heads capabilities, with bosses for injectors, rails, and carb brackety. I will also offer a 2V adaptor plate as an optional item, as well as the triple Webber intake. When completed, it will be offered in various configurations (ie: spring rates, valve sizes, porting, etc) with recommendations on cam profiles and induction, based on the performance level desired, vehicle specifics (ie: tranny type, rear gear ratios, etc) and aspiration (N/A or boosted). Or a bare head for those who prefer.

The exhaust patterns will remain the same as stock, so your existing headers (or turbos manifolds) will bolt up, although the 3rd and 4th ports will be split in the new design (no divider required). That was crutial to me since most of you already have headers and I saw no reason to have my prospective customers waste money purchasing new headers and selling theirs as used. Peticularily for those who recently purchased them.

I believe the 4V cylinder head is what most of you will be buying, thus the reason it will go to production first. It will fill the needs of most street/strip applications with the best possible performance gains, given the limitations of the design.

On the other hand, we are going to design and produce a cylinder head with all the limitations removed. In other words, not limited to using current stock or existing sub-parts. It will require a new header design as the ports will be rasied for better exhaust flow. Also specific to the new design will be the intake, the valve cover, and we are working on a shortened billet dizzy (to fit under the intake runners). Various valve arrangements are also being researched, possibly a four valve arrangement, or a hemispherical chamber? Basically, I gave him the go ahead to do what ever is needed to achive the best possible performance with absolutely no limitations on the design.

With all the new parts (headers, intake, dizzy, valve cover, etc) that need to be developed, plus the fact that sales will be in limited numbers, it will be costly in comparrison to the 4V head. Therefore, we are going to select one style of induction and design the head to work with it as a matched system. Rather than designing it to accomodate various induction applications. This is not to say it will not work with other induction types, only that optimum performance will be gained with a specific induction system.

I don't understand all the therories behind it, but enough to know that port and chamber designs change depending on the type of induction used, and all three must be match for optimum performance gains. Example: port velocity and shape wouldn't be as critical in a boosted system, as in a natuarlly aspirated head. Personally, I'm leaning towards a boosted system so we can gain every ounce possible. But would carbs or throttle bodies, single or multiple, be prefered over the other?

 

[CoupeBoy]

crossflow, MPFI with forced induction, DOHC on a belt drive with variable timing gears on each cam, 4 valves per cylinder in hemispherical chambers, with matching dish shaped pistons, and roller rockers. I am going to need 2 headers, one for turbo and one for NA/supercharged. Since I no longer require the internal camshaft for valve events maybe we could get rid of the cam completely. Dry sump oiling system and crank mounted ignition trigger.

-ron

 

[MustangSix]

You might recall the Krogdahl head that got some attention a couple of years ago. It was designed to fit both the Holden and the Ford motors as a retrofit. It was a DOHC hemi design with belt driven cams.

I thought it was a neat idea, but it was a true hemi and that chamber shape is not necessarily the best option for power and economy. Had they reworked it to be a four valve arrangement with a more modern pent roof chamber I think that the power, torque, and economy would have all been much better.

A pushrod crossflow design is probably going to be hard to do on an unmodified given the tight layout of the cam. But taking a page from the Krogdahl design, you eliminate that obstacle and only use the cam as a jackshaft to drive the oil pump and the distributor. Maybe even move the distributor to the head for easier access.

Rather than start completly from scratch, you could look at existing cylinder heads such as this 7M-GE Toyota or the AJ16 Jaguar.

Given a similar bore and stroke, if a pentroof DOHC head as efficient as the Toyota were available, the 3.3 liter Ford would be in the 200-220 hp range with just mild cams and carbs. A more aggressive version could be over 250 hp. Even into M3 territory, maybe?

 

[Does10s]

Mike,
I would personally like to see the "XF" intake style to be the old standby....4 barrel carb.
And you can EFI it if the customer wants to.
Later,
Will

 

[StrangeRanger]

I'm not a potential customer but I"ll jump in anyway.

Since all you're after with this head is the most extreme couple of percent of the market, I'd say multiple carburetion is the way to go. Either 3 x 2V side drafts on individual runners or a pair of carbs feeding 3 cylinders each with a balance tube between the plenums. (Two carbs gives better flow characteristics on an I6 than do three). The question is which carbs? Side drafts make much more sense on an I6, but 2 twin choke Webers or Dell'Ortos would look strange. I'm NOT going to suggest SUs no matter how well they fit the application and I'm not familiar enough with Stromberg side drafts to suggest them. If you go with downdrafts, the flow path isn't nearly as direct, but even a pair of 350s would be overkill (200 CID at 7500 RPM and 100% VE only needs 434 CFM.) Maybe a pair of Weber 32/36s?

 

[Stubby]

I would lean toward a fast burn chamber, keep the velocity up on the runners. Basicly build it for max effort EFI. Boosted engines do respond to high efficiency setups. The extra lenght on the runners is usualy in the intake anyway. Look to the Iron Vortec for inspiration.

I would cast it with a thick deck and deep combustion chamber for boosted applications with a flat top piston. I have built several blower engines and I prefer to retain the quench if possible. You can mill it for N/A applications. Best of both worlds with very little trade offs.

If it is a pushrod engine I would look at the geometry and try to use Chevy rockers and valves if possible. Cuss me if you like, but these parts are a dime a dozen and readily available. There is no reason for it to be a gigabuck setup if it don't have to.

Dual overhead cams are exotic, but you could copy the Pinto design and make some serious HP while using existing parts and cam masters for grinding cams. Who knows we might even get Esslinger and Roush to take us seriously. The rocker geometry on these engines is tough to figure out but once you get it, it works great. It would be a little bit taller.

Max it for EFi and leave the ability to lower the compression without using some morphidite piston and you can't go wrong. Then build a dual side draft EFI intake and a plenum with provisions for BOV and boost reference for guage and pump. The less adventurous can put carbs on it and use the plenum for ram air.

Make sure the rocker/valve geometry can handle whatever lift the ports can suport without getting into left field. I have seen some borderline setups on highend motors because the head wasn't designed for that much lift. The valves are angled toward the rockers and longer valves tend to crowd the rockers and the roller tips usualy end up on the edge of the valve when setup properly. I am sure you are taking this stuf into consideration but I thought I would mention it.

Gary

 

[CobraSix]

All Restrictions removed (and a deeper wallent):

MPFI with a Turbocharger.

I keep looking at my set up and wondering about MPFI. I still have a spare manifold that hopefully I can eventually get around to playing with.

Slade

 

[AzCoupe]

Much better. This is now moving in the direction I was hopping for, with some great responses and ideas. I am hoping to develop a head that will sell in the $2500 dollar range if possible. That's twice what the 4V will be going for, but much less than the Krogdahl head at 4K. I like Jacks idea of basing them on the Toyota or Jaguar designs. Keep the ideas comming. Thanks guys.

Basically, we are going to take the US 200/250 blocks, and design a crossflow head current with todays techonology.

 

[XFlow_Fairlane]

personally I think that if you are fronting the money for a head top end on the motor the cost of a header is not important. I would rather sell my old stuff (entire top end) to pay for a new header with better port layout and all. all I can say is BIG spacing on manifold bolts for big runners!!

 

[Stubby]

I think it will be difficult to keep the cost in reason(2500.00)if you do the DOHC. You have doubled the cost of parts. It would help if you could use existing parts, but the parts for the heads mentioned (Jaguar/Toyota) are rather expensive to start with. I have seen some Toyota cams advertised and the cams alone can consume about 25% of the projected price. It will also add alot of machine work to the bill. Alignboring for cams and machining for whatever type of valve actuation.

If the cam or cams become part of the head build the total cost needs to be in focus. You can add 2000.00 to the total price tag real quick.

I think with well designed ports and chambers you can achieve good results with a two valve head. One HP per Cu In without getting extremely radical isn't that hard to do.

I am not trying to critisize anyones ideas. I am only trying to add a little perspective. I admit I am a tightwad when it comes to spending money whether it's mine or someone elses.

 

[Lazy JW]

I agree with Stubby, it's gonna be mighty difficult to keep the costs down with any kind of overhead cam. Even a SOHC will add to the cost quite a lot. Sure would be sweet though 8) And you wouldn't have those nasty pushrods in the way of designing your ports.
Joe

 

[boston774]

Hmmmm

My comments come with a caveat that I am not a potential customer right now, although that may change within the next 6 months or so - I am looking for a good 91-93 M5, and the search is going very badly.

I'd go with two induction systems for the crossflow:

1) A good triple Weber/Dell'Orto setup. Since you are looking at a fairly bucks-up situation to begin with, this would go well. Nice thing about the Webers is that you don't need the electronics, which -can- cut down on the hassle.

2) An MPFI setup. Again, this would be doable, and may even have some common parts with the Weber setup if you use individual throttle bodies a la M3/M5.

I don't know about turbos. I think the market would be a lot smaller, and my suspicion is that guys who are into that may want to science out their own setups. I've got a Saab factory turbo, and the engineering that went into that makes me a little shaky.

And why bother with DOHC if you don't have to? Chevy LS1/2/6s routinly crank out 500+ hp highly streetable horsepower with pushrods and two valves.

 

[Anonymous]

Chevy LS1/2/6s routinly crank out 500+ hp highly streetable horsepower with pushrods and two valves.

Not a fair comparison. There are way too many basic desgn differences to be placing them in the same boat, just because they both have pushrods.

(A 1940 John Deere has pushrods, sooo.....)

 

[xctasy]

So does a 630 hp at 7500 rpm Vee-Eight Super Car engine used in Aussie Touring cars. (302 Boss engines with alloy heads and EFI)

Or the 390 hp quad Weber 289 GT40 in 1967.

And the little 88 cube Mini OHV engines dating back to a 1950;s design. They give 125 to 165 hp at 7500 rpm with one IDA 48 and its still streetable.

The dancing knitting needle engine isn't dead yet!