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Kudos To Doc Dodge (Doug Dutra)!!!!!
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Author:  63Dart [ Tue Jan 04, 2011 2:30 pm ]
Post subject:  Kudos To Doc Dodge (Doug Dutra)!!!!!
Hi All,

Some of you who have been here for a while might remember me from a few years ago (hi Menko!). I *used* to post a lot. . .

Well, I ended up going through a divorce and my life got kind of upside down for a while. My Dart was also one of the victims, and I didn't take care of it like it deserved. Amazingly (or not surprisingly) it still continued running.

:D

Well, this is where Doc Dodge comes in. . .

A few years ago, he built a nice motor for that Dodge, and despite my lack of care, it just continued to run and run. And not just run - that thing was FAST. Well, I ended up cracking the block (long story), and Doug was nice enough to offer to rebuild the engine for me yet again.

This iteration is simply AMAZING, even more so than the last one.

(And I promise to take care of it!!!!!!!)

The current motor idles smooth (Doug had a special cam ground for it), yet should pull strong up to as much as 5500 (I am still on break-in oil - so haven't redlined it yet). It's not just a strong slant six, it's a strong motor, period. Driving the car now feels a lot like my old 302 Mustang used to feel - effortless power at any RPM.

That Doug could do that, and still get a smooth idle and street driveability is just amazing to me. Even more amazing is that it does all this on regular octane gas.

A little about the car:

1) My daily driver for 10 years.
2) Other than some cars when I was married, I have only owned Dodge Darts since 1982 and this is only my third one.
3) I have retrofitted it with SSBC disc brakes, urethane suspension bushings, KYB shocks, racing springs in the rear, anti-sway bar, etc. . .
4) The motor uses two BBS carbs on a NOS (new old stock) offy intake, has electronic ignition, a custom cam, Cliffords, Flowmasters, 2 1/2 inch piping, and I think some head work (Doug did something magic, I am sure). . .

Anyways, when I get a chance, I'll YouTube the sound so you can hear it yourself - it's the most awesome sounding Slant I have ever heard - it's now very deep and smooth sounding - kind of like an old Jag six. Hard to describe.

Doug has been just awesome to work with - not only did he do an incredible build on the motor, but he fixed a bunch of other stuff too - for example, I put my back brakes on wrong when I rebuilt them recently - and Doug noticed and fixed it for me when he changed out my gears.

I am a very happy camper now!!!

Image
Author:  63Dart [ Tue Jan 04, 2011 2:36 pm ]
Post subject: 
Here's the car:

Image
Author:  emsvitil [ Tue Jan 04, 2011 3:13 pm ]
Post subject: 
You wouldn't happen to know the specs on the 'special' cam?
Author:  Doc [ Tue Jan 04, 2011 3:24 pm ]
Post subject: 
Thanks for the Kudos...
Yes, that Dart runs well. :twisted:

Truth is, it is nice to get a "second chance" on an engine build... you can really "nail it" after being able to run the combo then re-adjust things.

I had my notes from the first build and ran compression checks and degreed the cam on the old cracked engine, to confirm where we were, then adjusted the new build from there.
We put in a little more static compression and retarded the cam a few degrees... everything else was basic rebuild stuff.

The cam is the Erson RV15/295 RDP.
DD
Author:  63Dart [ Tue Jan 04, 2011 3:45 pm ]
Post subject: 
Yes - that cam is really shining now with the slight tweaks!!! It's kind of like having a hard core "performance" cam, without having the live with the crappy idle and lack of low end.

It's like the best of both worlds (more power throughout RPM range AND a tractable motor).

It also seems to "like" the current gearing more (I think it's 2.93 now, instead of 3.23, yes?) The cam really shines on midrange stuff - with the previous gears, and my 14 inch wheels, it just didn't spend that much time on midrange, since the engine would spin up so quickly.

I don't know how to express this this in a way that makes sense - it's kind of like the previous rear gear ratio made the car too "easy" for the cam's torque or something.

Even right now, while I am still keeping the RPM's way below redline - I have to really watch it, since flooring the car in drive at XX speed will guarantee that the car hits YY speed in just a few seconds.

I am a convert now to the idea of using a reasonable cam vs. using a big lumpy cam, at least on a street motor. . .

EDIT: here's a quick video of the motor - my cam phone has crappy audio - so you can't really hear it right - I'll do a better one when I get a chance. BUT - you can see how quickly it spins up, even with a little hesitation (the motor is semi-cold from sitting in the parking lot while I am at work today). There is no hesitation once the motor is warm.

http://www.youtube.com/watch?v=lF-i0q2dvBU

ALSO - I know you can see my license number -

:D
Quote:
Thanks for the Kudos...
Yes, that Dart runs well. :twisted:

Truth is, it is nice to get a "second chance" on an engine build... you can really "nail it" after being able to run the combo then re-adjust things.

I had my notes from the first build and ran compression checks and degreed the cam on the old cracked engine, to confirm where we were, then adjusted the new build from there.
We put in a little more static compression and retarded the cam a few degrees... everything else was basic rebuild stuff.

The cam is the Erson RV15/295 RDP.
DD
Author:  speedy [ Tue Jan 04, 2011 8:36 pm ]
Post subject: 
Interesting! I'm waiting on the same cam to arrive from Erson for my build. Hope I can get it dialed in just the same :D
Author:  63Dart [ Wed Jan 05, 2011 2:08 pm ]
Post subject: 
It's very good. I don't know how to explain it well, since I'm not much of an expert - but the short simple way is that it will make a smaller motor act like a larger motor.
Quote:
Interesting! I'm waiting on the same cam to arrive from Erson for my build. Hope I can get it dialed in just the same :D
Author:  Doc [ Wed Jan 05, 2011 4:58 pm ]
Post subject: 
Quote:
Interesting! I'm waiting on the same cam to arrive from Erson for my build. Hope I can get it dialed in just the same :D
This cam seems to work well with the DCR set to 8.0 to 1 (pump gas)
On the first build, static compression was set at 9.01 to 1 and DCR ended-up at 7.72

Knowing that, we took an additional .040 off the replacement block and doing that put the SCR at 9.33 and the the DCR at 7.994

Bottomline, this cam works well when the static compression is in the 9.3 - 9.5 range... depending on how you phase (degree) the cam.
DD
Author:  olafla [ Wed Jan 05, 2011 6:13 pm ]
Post subject: 
Hi 63Dart, nice car with an awesome engine - good combo!
I am also waiting for my RV15/295 RDP cam, and I have to do a full overhaul on the engine (w/peanut head). I also have engnbldr valves 1.70" In. and 1.44" Ex.

I hope you don't mind me asking a relevant question, even if it means Doc may have to answer, without me taking over this thread:

I wonder what kind of work is done on 63Dart's cylinder head. Is this a stock '63 or a later model head, and what is the chamber volume?
Quote:
With careful "blueprinting", machining and parts matching, these areas Quench Dish 2.2 Piston can be used to create a high turbulence, "closed" combustion chamber design. The chambers in the photo above are "smiling" because this type of chamber design makes lot's of power!
Can this be done to advantage when using the RV15 RDP cam, or is it a wasted effort here, and only meant for more extreme builds?

Apart from port blending the intake side and a general clean up, do you have any thoughts on what to do to improve the combustion chamber specifically for the RV15 RDP cam? Piston specific advise?

Is all material for raising the compression taken off the block, or is there a mix of head and block?

Olaf.
Author:  Doc [ Thu Jan 06, 2011 10:12 am ]
Post subject: 
Wow... your questions are basically the same ones I am currently asking myself. :shock: :D

Just before doing the rebuild for 63 Dart we did the "Zing" engine and installed it into my daily driver Dacuda... that is a long rod / short piston, light crank and zero deck w/ quench engine.

http://www.slantsix.org/forum/viewtopic.php?t=41320

The short answer is that these builds have the open chamber / closed chamber / quench difference you are asking about and have simular cam, static and dynamic compression numbers.
First impressions, "seat of the pants"... the two combos "pull" about the same with the Zing engine feeling a little faster up & thru the RPMs.
Trouble is, both engines are still in the break-in stages so we will need more time to collect data. (how they "pull" at higher RPMs and where the power falls-off)

As for the milling work done on the 63 Dart engine, the head was milled to get 54 cc's and pocket ported on the first engine build "go-around" and the block was "kissed" to true it up.
This time, we milled more off the block for the second round build and just "kissed" the head surface to clean it up. Head is still at 54 cc's and the block is now at -.120 with a cast SL6 flat top piston.
Both engines are running the .020 thick shim steel head gasket.
DD
Author:  wjajr [ Thu Jan 06, 2011 12:13 pm ]
Post subject: 
Doc,

My present build has what looks to be stock pistons & rod length. Head is same as Olof’s, shaved enough to give 9.5 CR with Fel-Pro head gasket. I do have a new factory steel 0.20â€￾ head gasket ready for any changes.

If I do change from my unknown early nineties Clifford “race camâ€￾ to your RV 15, knowing that my dynamic CR will move up, what is the highest compression ratio compatible with 93 octane pump fuel.

Will my 3.55 rear be an asset or detract from overall performance with the RV 15 cam?

Bill
Author:  63Dart [ Thu Jan 06, 2011 4:30 pm ]
Post subject: 
Thanks all for the compliments on the car and engine! Yes, please ask away - Doug can answer the more technical questions.

Just thought I would give a small update. It did have a *little* pinging under light freeway acceleration - I put in premium gas, and the pinging is now gone. It's not surprising, given the compression ratio, etc. . . It may have just been a bad tank of gas, too.

I picked up the car in the Bay Area, but I actually live in the Sierra Foothills at about 2200 feet - I can probably switch back to regular (or mid) up here, since it's going to run a little richer on this thinner air. The pinging was VERY slight - but as you all know - it's not good to take a chance - especially with such a nice motor!!!!!

I followed Doug's suggestions on break-in - which are basically drive it conservatively for a certain number of miles, then switch out the break in oil and drive it normally.

Anyways, last night (after putting in clean oil and driving for another distance of miles) I took it up to 5200 RPMs - and it was STILL pulling, but I didn't want to really see what it could do until I put a few more miles on it. My sense is that it will easily spin up to 5400 - it was pulling VERY strong at 5200.

The combination of the true "2 into 6" intake and the "6 into 2" exhaust gives it a very mean sound. Very European, somehow.

I will tape a better video to give you a better idea of the sound.

I had absolutely no problems over the Altamont pass coming home last night - pretty much went 75 to 80 the whole distance, with a few stretches slower so that I wasn't running the motor at the same RPM for too long. Could have easily gone 100 MPH over that pass.

With the taller gears, and the increase in power and torque, my gas pedal barely has to be pressed to move along at a nice clip. I am guessing that my MPG's will be excellent.

:lol:

Doug - I promise I am being very careful with it, and treating it very well - I just love this motor.
Author:  olafla [ Thu Jan 06, 2011 9:53 pm ]
Post subject: 
Quote:
First impressions, "seat of the pants"... the two combos "pull" about the same with the Zing engine feeling a little faster up & thru the RPMs.
I know you have done some seriuos work to lighten the crankshaft on the 'Zing'. From your experience, will the difference in weight between a forged and a cast crank be enough to make the difference mentioned above?

Olaf.
Author:  Doc [ Fri Jan 07, 2011 8:57 am ]
Post subject: 
I agree... the Zing engine likely revs better because of it's light rotating assembly... more then cam or cam timing differences.
It will be nice to get some redline info. on both combos, once they are fully broken-in.
My guess, both engines will likely fall-off the power near the same RPM... but the Zing combo will just get there a little sooner.
DD
Author:  63Dart [ Fri Jan 07, 2011 11:36 am ]
Post subject: 
Yes, one thing I am going to do this time - that I did not do last time - is keep Doug completely "in the loop" on how the engine performs, etc. - especially as it "breaks in."

I'm such a dummy sometimes! For the first engine he did - I did not completely realize how he uses the data to further develop other engines.

kt
Quote:
I agree... the Zing engine likely revs better because of it's light rotating assembly... more then cam or cam timing differences.
It will be nice to get some redline info. on both combos, once they are fully broken-in.
My guess, both engines will likely fall-off the power near the same RPM... but the Zing combo will just get there a little sooner.
DD
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