[sdbob]

Just try to add small V story.Don't want to hijack. I witnessed the bldg of a V engine back in the 70s. The engine used a special factory small journal crank. I don't recall the cubes but bigger than 428. The engine was installed in a dirt track semi late tempest GTO. The car had a dominator cut in half for class with the V intake. That car would run away from the 454 chebies and they did not like it. Thats the short story.I'm watching your build Don thinking about putting a set on SD block.

[dci]

Charles, These are Harland Sharps that I contracted them to build for my heads. They will be available in ratios from 1.5-2.0 to 1 and it looks like they will retail for just under $1,000.00. That's a smoking deal not to mention the valve train stability you will get with them. Shaft rockers make valve adjustment a breeze and they hold their lash longer. I'm not sure if everyone caught that a 7/16" pushrod will work with minimal clearancing or not, but that also means a 1/2" pushrod will work as well with just a little more.

sdbob, I have heard the same stories about RA5's from back in the day. It's really to bad that GM shut the RA5 program down. It would been interesting to see what could have developed from it.

[tom s]

Guys,there are so many V stories out there.Most you hear with a stock V intake should be takin with a grain of salt.The dual plane intake is the choke.The highest real HP I have actually seen on a dyno was 6700 with a lot of compression and a lot of cam.The sheetmetal intakes run by the likes of Jerry Leak(spelling)Stinebeck Rudy Diffus is what woke them up.Virtually every pump gas REAL street driver with a stock intake was done at 6200.Dons intake should open the RPM range that the heads were designed for.Tom

[estep455]

Originally Posted by dci

If you guy's can't tell Rick is really excited about finally getting to build his child hood dream engine. There are few things in life that make people really happy and cars with lots of HP are one of them. Rick came to me at Norwalk the first year I had my first prototype head there, and (keep in mind he is an engineer type of guy) he literally used dial calipers and note pad in hand to record data from my heads LOL. So to say he is excited is an under statement. Thank you Rick for being one of my best supporters!!!! It's guys like you that make it fun for me and my guy's.


Tom can probably share more RA5 stories than almost anyone out there. He has been into RA5's for as long as I can remember and has possessed some really exotic pieces. A few other guys that come to mind that could share some RA5 stories are Nunzi, and Jerry Steinbeck. These guy's actually raced with RA5's back in the day and ran 8's before anyone else was barely breaking into the 10's. Nunzi and Jerry both were making right around 2 HP per cube back in the day without today's technology.

The RA5 platform leaves allot of room for growth as well as durability. The RA5 heads are not limited by CSA like other Pontiac heads and the divorced exhaust ports help disperse the exhaust heat more evenly over the heads. There is a couple of good articles on the web that talk about a cylinder head that Junior Johnson tried secretly on his Nascar engines around I believe 2007. Nascar quickly snuffed it out because it gave him a huge advantage horsepower and torque wise, literally letting his cars lap the competition. That head was a split port or tunnel port design like the RA5's. Some of you may already know this, but the RA5 head is a copy of the Ford Tunnel port head form back in the day.

Lmao! Rick was walking behind my trailer that night at Norwalk and heard me telling some friends that I felt like I was holding your first born or something when you left the heads with me. Rick stopped dead in his tracks and immediately wanted to see them. He was blown away and extremely excited just to see them (he had no idea how I felt having them in my possession that weekend). I knew then he was hooked! Rick I cant wait to see your build and the other Don lol. I am also anxious to get my RA5build with Don and Brandon going!!!!! I feel like we will be at the power level I have been after for a few years now with a more reliable combination. Thanks again Don for all of your devotion and hard work!!!!!!! You truthfully have no clue how thankful I am for it and your help personally.

[dci]

Thanks Danny, Your right Rick guarded his heads like they are his first born LOL.

Bryant AKA 455Firebird1969, I just received my valve cover castings from the new foundry I am trying, and they look awesome. So I will be sending yours with your T-shirt order out this week. Thanks for the order!!!!

[dci]

Got a question for you guy's. Who here has owned or driven an old mid to late 60's Nova, Chevy truck, Ventura or something with a inline 6 in it, and what did you think of the torque it made? Once I get a couple of responses I will post a couple of pic's I took and get your thoughts again. I had a 71 Ventura with the 230 inline 6 I drove for a couple of years with one, and was really surprised with the amount of torque it made especially with the 2 speed. Let me know your experience if you have any. I am going somewhere with this so bear with me here.

[tom s]

Don,I had a inline 6 in my last GMC Envoy,the one before was a small V8.I did not see much diff in everyday driving.Both equal small SUVs.Selective 4 whld,same trans etc.The inline got a touch better GPM around town and really no better on the road.The 6 was 290 HP and the little V8 was 310 I believe.Not old inline 6 but still a pretty good compare in my mind.Tom

[455firebird1969]

67 OHC Firebird, 76 Nova and a 85 CJ7, all inline six layout

[455firebird1969]

Towed a broke mustang on a dolly with the 258 in the jeep

[ho428]

Towed an inboard ski boat with a 300 six in an F150 for a few years, towed good on the low end but not enough hp.
My 1 bbl OHC six Bird can't get out of it's own way. Needs more carb.

[Sirrotica]

Siamese ports, especially in the GM 6, middle 4 cylinders. The end ports have their own runners. Torque producing ports, with an unconventional port shape?

It's not to difficult to get 300 HP from a 292 chevy and still have an abundance of torque left with Siamese ports would be my guess. The bore and stroke of a 292 is an over-square engine similar to a Pontiac with a high deck, long stroke, long rod engine. The 194, 230, 250 is still similar to a smaller Pontiac and uses Siamese ports in the center cylinders.

[BruceWilkie]

Originally Posted by dci

Got a question for you guy's. Who here has owned or driven an old mid to late 60's Nova, Chevy truck, Ventura or something with a inline 6 in it, and what did you think of the torque it made? Once I get a couple of responses I will post a couple of pic's I took and get your thoughts again. I had a 71 Ventura with the 230 inline 6 I drove for a couple of years with one, and was really surprised with the amount of torque it made especially with the 2 speed. Let me know your experience if you have any. I am going somewhere with this so bear with me here.

My 64 Dart 225 was zippier than my brothers 67 camaro 250 both 3 spd sticks. That said, I'd love to do a OHC 6 Pontiac in a first gen with turbo and efi with some aftermarket rods etc.. Too bad the Pontiac head didnt have the exhaust on opposite side of intake.

Maybe that could be your next cylinder head project??? POHC6TTF lol ! Move over Toyota!

[scooter1966]

Originally Posted by BruceWilkie

Maybe that could be your next cylinder head project??? POHC6TTF lol ! Move over Toyota!

x2 an alum replacement would be nice

[scooter1966]

Originally Posted by BruceWilkie

Maybe that could be your next cylinder head project??? POHC6TTF lol ! Move over Toyota!

x2 an alum replacement would be nice

[ho428]

If I recall Quentin at Primatech was working on welding two V6 aluminum heads together to make an Aluminum DOHC.
Not sure whatever became of that project but they got pretty far along.

Only reference I could find right off.
http://60degreev6.com/forum/showthre...ch-DOHC-6-head

[dci]

Well Brad must have seen one of the early inline 6 cylinder heads before. Take a look at these pic's of an inline 6 we are rebuilding for a customer right now. The intake ports are crazy big and dis functional for the amount of torque these things make. No dividing wall at all and a big bolt boss or tube right in the middle of the entrance of the port. When I seen this it made me think that maybe the RA5 heads are not so bad LOL. I have seen several comp eliminator dragsters with these early GM inline 6's in them with factory heads and these guys are spinning these things to the moon. I don't know if the guy's that are running them make dividers or not, but even if they do there is only so much you can do with this ports design. I was just amazed with the amount of torque my 71 Ventura made with this port design after really looking at them. Especially with a 2 speed powerglide trans and 3.08 rearend gear.

[dci]

I just placed an order for another run of DCI RA5 cylinder heads. The first run is sold out!!!! I sold the last set I had yesterday.

Thank you to everyone that have supported me and helped my project come together !!!!

[RAMAIR RICK]

Don, Spring is in the Air, and Ram Air V's are everywhere!

[RAMAIR RICK]

Don, I was talking with Jim Robertson the other day about my DCI Ram Air V heads that he is currently working on for me. Jim stated he has the seats done for the 2.32 intake and 1.68 exhaust valves, so he will start with an cast intake and exhaust port to get our baseline and then work on getting the port to the parameters that will be required for my engine's requirements. I am very much looking forward to what the next couple months will bring during spring.

[dci]

I agree Rick, I'm looking forward to seeing what Jim's results will be as well. I know Jim told me, but I cannot remember which flow bench he has. I am interested in seeing my heads on another bench for comparison. I use a Superflow 600 that has a max of 597 cfm.