[dci]

That's the cool part about my intake, You can have and do anything you want. Your not tied down to one specific style of carburetor. I also tried to get the runners as close to equal as I could on all the ports.


Don Johnston
DCI MOTORSPORTS INC.
330-850-5050 shop
330-628-3354 cell
Designer of the DCI Tiger Heads and the NEW DCI Ram Air 5 Heads !!!!!

[grandville455]

Don, How will these heads /headers fit in a 2nd gen?

[Curious George]

And a 1st gen?

[Baron Von Zeppelin]

Originally Posted by grandville455

Don, How will these heads /headers fit in a 2nd gen?

(not Don - just making a response)
2nd Gen F-Body will probably have obstacles to deal with about a breather set up.
Low profile aftermarket mini breather and shaker bolted to hood-
or flat hood with aftermarket scoop.

Little - to no - wiggle room from stock component height.
Between extra height in head - and likely extra height of intake - probably going to be more than the aftermarket xtra-drop base pan will cure . (?)

1st Gen and A-Body not quite as fussy.
But probably no worky with stock Ram pans.

2nd Gen Exhaust should be same parameters as 68-72 A-Body
So long as Don makes them specifically for his heads.
The raised ports / raised castings - i'm thinking - will make his heads need proprietary exhaust on stock cars. unless i'm (wrong) over-speculating

[Baron Von Zeppelin]

Gets hard to keep track from page to page sometimes -
here was a reply about exhausts from previous page.

Originally Posted by dci

I am working with Mad Dog headers in Michigan for the headers. He is excited about starting a new product line and welcomed it with open arms. He currently has RA5 headers for early F-bodies, but nothing for A-bodies yet. Although he is going to have to make a few alterations for my heads because I raised the exhaust port about a 1/2".

[dci]

Well the heads are a little taller than factory heads, but i raised the valve cover rail just a little. By doing this it will allow you to use stock height valve covers with roller rockers. So I have not done the math yet to see what the actual difference is between a stock head with TALL valve covers, and my heads with STOCK valve covers. I think though that it will be really close to the same outcome. As for the intake. I designed it to be close to the same height as a factory cast iron one when installed and I used a 68 firebird for the mock up. I do not have any intakes yet to do an actual install to check. So right now all I can do is hope my cad model is accurate. We should know soon though.

As for headers. There are not allot of headers still out there from days past. So I am working with Mad Dog to build headers that will fit my heads. I can tell you from personal experience that the old headers that were available back in the day did not fit very well. I built a set for a customer and they fit pretty good. I installed a set of JR's and they fit like @#$%. So with Mad Dog's quality and fit. I think it will be a big improvement.

I tried to remove as many obstacles as I could for the end user!!! I know from being in business for 30+ years though. That there are unforeseen problems that will come up. For example: I just installed a BBC 427 in a early Corvette. Should be a bolt in with the right mounts. Right? Well it would have been if the car had not been wrecked 25 years ago!!! The passenger side frame rail had been replaced and was not done correctly. So when we removed the SBC. We did not pay any attention to the fact that the motor mounts were modified. When we started to install the BBC it did not line up. Long story short, we got it fixed right and everything is good now. So just keep in mind that things wear out or get altered and may cause unforeseen problems.

Don Johnston
DCI MOTORSPORTS INC.
330-850-5050 shop
330-628-3354 cell
Designer of the DCI Tiger Heads and the NEW DCI Ram Air 5 Heads !!!!!

[428RA4]

We don't have fit problems, we have issues...

[dci]

I just measured my head with a stock valve cover, and a stock head with a Moroso tall valve cover. The difference between them is about 1/4" mine being a little taller with the stock cover. If it does not fit your application with my heads. You could mill about .200 off the valve cover rail and get the clearance back. Although it may not clear every type of roller rocker if you do. So you would need to check that first .


Don Johnston
DCI MOTORSPORTS INC.
330-850-5050 shop
330-628-3354 cell
Designer of the DCI Tiger Heads and the NEW DCI Ram Air 5 Heads !!!!!

[RAMAIR RICK]

Hello Don, I realize that today is April 1st, so all joking aside, any ETA on your completely machined set of heads?? Also any ETA on your very interesting intake manifold?? I can't wait for Jim Robertson to get his hands on BOTH the intake manifold and a set of the NEW RAM AIR V HEADS!!! Spring is here and I can't wait. I am very much looking forward to moving forward with my engine program. Thanks in advance for any insight and or Performance updates on the air flow potential of your new heads.

[dci]

Hi Rick, Heads are a couple of weeks out (keeping my fingers crossed), Intakes month, 2 months ???. As cast 2.200" valve 400+ cfm. Ported 2.340" valve 500+ cfm so far and just starting to figuring things out!!!!!!
Don't let the big flow numbers scare you. Port speed is really good and the as cast head flows 360+ cfm at just .650" of lift. So with a very street-able camshaft. The engine is still going to make really good mid range power.


Don Johnston
DCI MOTORSPORTS INC.
330-850-5050 shop
330-628-3354 cell
Designer of the DCI Tiger Heads and the NEW DCI Ram Air 5 Heads !!!!!

[RAMAIR RICK]

Hello Don,
It sounds like that your complete package for the heads/intake/valve train and headers are coming together, which is great as many people will be able upgrade/switch over to your Ram Air V heads knowing you engineered out a package that will work for them. That being said, what is the largest intake valve that someone would be able to run in a 4.35" or larger bore? Lastly, if I remember correctly, I believe that your valve angle position is JUST 10 degrees!, Wow, that should really help the flow to the cylinder. Based on that, how much better does it allow you to design a much more efficient combustion chamber and hopefully better valve reliefs in the piston top without getting to close to the top ring groove. Thanks in advance for your response.

[dci]

It is finally all coming together!!!!

My valve incline is indeed 10 degree's. This helps with allot of different things. Like you stated the combustion chamber can be very shallow allowing the valves to begin to enter the cylinder faster and un-shrouding them right off the seats. It also allows for more room between the valves and the pistons for bigger lift cams. Engines with small combustion chambers and dished pistons generally will make more power. On a 4.350 bore max effort combo. You can get a 2.450" intake valve and a 1.65" exhaust valve with the proper valve locations. This will still leave .170" between the cylinder wall and the intake valve. We have not tested a port yet with that big of an intake valve. So I am not sure what kind of flow they will produce, but we do know that we can get enough CSA to support that size valve. Like I stated earlier, we have only tested up to a 2.34" intake valve and we so far have got a little over 500cfm. As the heads start to get out and guy's start learning what they like. I think we are going to see some pretty potent Pontiac's.


Don Johnston
DCI MOTORSPORTS INC.
330-850-5050 shop
330-628-3354 cell
Designer of the DCI Tiger Heads and the NEW DCI Ram Air 5 Heads !!!!!

[grandville455]

I'm Sure its been asked Don, But How would these fair on a smaller 4.155 Bore and what valve sizes would u rec for it? Have u said the Pricing for complete heads yet?

[dci]

Darby, The cool part is I designed these to fit on a 4.155 minimum bore with a 2.200 intake valve. So they will perform well even on small bore engines. All of our flow testing has been done on a 4.200 test fixture as well. So all of my test data is accurate for smaller bore combo's. As for pricing, It all depends on what the customer wants. I originally was going to offer complete sets, but everyone I have talked to wants something a little different. So it looks like everything I assemble is going to be application specific. The bare heads with seats and guides start at $3499.00 a set. I will be offering a $150.00 discount for anyone that pays with cash.


Don Johnston
DCI MOTORSPORTS INC.
330-850-5050 shop
330-628-3354 cell
Designer of the DCI Tiger Heads and the NEW DCI Ram Air 5 Heads !!!!!

[grandville455]

So were thinking maybe $4000 with valves and valve job then? You have posted the port speed is good for a street/strip deal right? I thought I read it in this thread?
Thanks Don!

[dci]

Your in the ballpark and the air speed is great!!!


Don Johnston
DCI MOTORSPORTS INC.
330-850-5050 shop
330-628-3354 cell
Designer of the DCI Tiger Heads and the NEW DCI Ram Air 5 Heads !!!!!

[68blackbird]

Don

Is a cam change required for your heads? Changing firing order?

Rich

[quick67bird]

Originally Posted by 68blackbird

Don

Is a cam change required for your heads? Changing firing order?

Rich

A cam change will be required just becuase of the change in exhaust and intake valve layout.

I sure can not wait to buy a set. I am saving up my pennies now.

[RAMAIR RICK]

Don, as you know, next week is Easter. That being said, is the Easter Bunny going to have any Surprises for all of us in our Easter baskets next week other than Chocolate? And to the question on the cam, will we be able to use a standard diameter Pontiac distributor gear? Do you have any Cam manufactures that are working with you for cam blanks for Roller Cams, either Hyd. or solid roller? One more question for now, do you know the overall average valve length that will be required for most applications??

[tom s]

FYI,I have been buying V cams from Comp for years.Only rollers.Tom