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225/6 performance upgrades
https://slantsix.org/forum/viewtopic.php?t=25523		 Page 1 of 2
Author:  jskv12 [ Thu Oct 25, 2007 3:37 pm ]
Post subject:  225/6 performance upgrades
I am a new member of this group and in need of much advice. I am the original owner of a 1975 Dodge Dart Sport given to me by my father as a graduation present. I am in the process of restoring the car with the help of my young son to give to him when he leaves for college.
I am looking for available performance upgrades for the motor. I want to keep it original other than improving the driveline and suspension/brakes. I need engine advice. The car currently has 90k miles and is equipped with a one barrel carb and no cats on the exhaust.
Any and all advice is appreciated. I want the car to have as much power as a good drivable street /6 can have. Thank-you all in advance.

Jeff
Author:  66aCUDA [ Thu Oct 25, 2007 8:02 pm ]
Post subject: 
What State are you in and do you have to pass emissions tests?
This will allow people to help you better. Other things how much money do you wish to spend and what is your mechanical ability ?
Frank
Author:  Doctor Dodge [ Thu Oct 25, 2007 9:00 pm ]
Post subject: 
Welcome to the forum.
Does the car run now?
What is your concern or problem(s)with it... is the car slow to accelerate?
DD
Author:  runvs_826 [ Thu Oct 25, 2007 10:39 pm ]
Post subject: 
I bought my 75 duster when I was in high school, very dissappointed it wasn't as powerful. However, I love it know and as a kid know really what's important to start at. Time seemed to be what limited me on my project being as it didn't cost me to much, but I have a strong mechincal background.
Doug suggested a while back to change out the gear ratios, this is exactly what I wished I would have started with. An 8.25 is relatively easy and cheap and will be very sufficent on a budget (also look at ford 8.8).
Depending on the shape of the engine and what your overall goal is a four barrell is an absolute must for performance, I went with a two barrell got it all set up and drove it for 2 months! Valve adjust and headers/dutra duals and you got a hot little car.
Last, if the engine is honestly in good shape you could pull the head or buy another one, get bigger valves (SI 1.77/1.44 - $100) home polish the bowls, get the machine work done for about $400+ in the head and it will really scream. Mill .1 off the head to make it come alive. I think you could change out the cam with the engine in (270 dur with .44-.5lift), otherwise just slap on the new head. If you have the time to do a full rebuild that is great, but usually the bottom ends hold up for a looooooong time. hope that help from a kid's perspective.
Author:  Aggressive Ted [ Fri Oct 26, 2007 6:45 am ]
Post subject: 
Author:  carpdar [ Fri Oct 26, 2007 7:56 am ]
Post subject: 
I'm starting to think we should put together a sticky with a ton of information on performance upgrades along with strengthening tips for high rpms for new and for the tuners.
Author:  Aggressive Ted [ Fri Oct 26, 2007 9:23 am ]
Post subject:  Example Build sheets
When I first came to this site, that is exactly what I was looking for. Some different examples of various builds from mild to wild, but was surprised that as long as these engines have been around there were not more examples.
So Doc set up the format that I used for my "torque" build. Doc posted one and I posted mine. They should be published/located in the articles section which would be great. Kind of like shopping in a candy store. Pick a known build, have the email for the builder for reference and maybe a picture or two. That would help allot of general questions. Then the forum could address specific questions. To do my "torque" build took about a full year of research and I still missed a few areas. Doc could screen the write ups and build sheets to make sure they follow the format, then make them reference. I am all for helping share what I have learned. In fact, I have three more blocks to build. One will be a back up, one with a little more aggressive build and then a race motor. :D

Now that I know these engines can put out the power, I am getting a truck with a SL6. All my other cars have 375 HP 440's, so my expectations of the SL6 are pretty high. I have not been disappointed in my SL6 rebuild at all. It really woke up, very peppy and is allot more fun to drive. :D :D :D
Author:  jskv12 [ Fri Oct 26, 2007 11:13 am ]
Post subject:  /6 performance upgrades
Thank you all for the guidance. My car runs perfectly and I do not have emissions to worry about. It has only 95 hp and is quite sluggish as it has been from new. My goal is to extract as much performance from the motor as is reasonable with good drivability. I am considering a five speed (three on the tree now) and any appropriate engine mods. I am not limited by dollars in the reasonable sense. The tranny is about 3300 and I figure another five or six for the motor. I will spend what is necessary toward my goal but certainly less is better than more all other things being equal.

What do you think about the Clifford motor stuff? I spoke with them yesterday and it was intriguing. I am mechanically capable and have a lift and a really well equipped shop. I just want to learn from those of you who know far more about this project than I do. I love my Dart for many reasons and am very excited about this project and to be able to pass it on to my son.

Again, thank-you all and please send along any and all appropriate advice. There is no hurry on the project I have slated about four years which of course means probably five but it's all fun stuff.

Jeff
Author:  Aggressive Ted [ Fri Oct 26, 2007 11:43 am ]
Post subject: 
Your 75 Dart Sport is a nice car and deserves a little love, especially since your passing it on to your son.

If I were doing a rebuild with a five speed in mind, I would get the weight of the car documented, decide on a gear ratio, then build for either torque if you go with a 2.76 (I never go over 3000 rpm, cruise is 2500) or if you want to go with a lower gear ratio, then you need to build for more rpm.

You have to be selective on the Clifford parts. If you live in the north or in the mountains, you need to heat up the manifold to get better atomization of the fuel. Some of their manifolds will not bolt up to the exhaust and run cold. One is heated with water. Some folks have not gotten their parts in a timely manner.

Doctor Dodge's cam selections through the Erson Cam buy are better than a Clifford. The Doctor's Dutra Duals are better for a daily driver compared to Clifford's shorty headers. The shorty headers do not build much torque either if your thinking of using a 2.76 gear ratio. If a four barrel tickles your fancy, Offenhauser and Weiand make manifolds that bolt to a stock manifold. See Doug's article on the stock manifold mod.
You can have your cake and eat it too with that set up! :D
Author:  slantvaliant [ Fri Oct 26, 2007 1:42 pm ]
Post subject: 
Welcome to the Forum!

Modern tires will make the car safer. Wider 14" or 15" rims will allow much better tires, improving braking and handling. I like 205-60R15's on 15X7's on my '64, but I beleive your Dart Sport can take bigger tires.

What brakes do you have on it now? If you have drums up front, I'd strongly recommend converting to disks. No sweat swap on a '75.

How are the suspension bushings, balljoints, etc? While you're swapping out brakes is the time to go a little further and rebuild the front end.

A front sway bar, if you don't already have one, would be nice as well.
Author:  HEMI6 [ Fri Oct 26, 2007 4:08 pm ]
Post subject: 
HELLO EVERYONE I AM NEW HERE, I SEE SOME REALLY GOOD IDEAS HERE ARE A FEW OF MY OWN. FIRST FOR MILEAGE WITH A 225 STOCK ONE EITHER REBUILD OR NEW OUT OF THE BOX HOLLEY, CARTER, OR WHATEVER YOU PREFER 1BB DON'T VARY ALL THAT MUCH. I WENT WITH A DUAL POINT DISTRIBUTER AND THEN SWAPPED OUT FOR A MOPAR PERFORMANCE ELECTRONIC IGNITION WITH CHROME BOX THIS REALLY LIVENS THINGS UP .0034 GAP E-PLUG, SPLIT FIRE , OR BOSCH, TAKE TO .0044, IF YOU ARE SET UP WITH MORE THAN A STOCK CAM. HIGH VOLUME LOW PRESSURE OIL PUMP, WITH A THRUSH GLASS PACK, AND 2.76 GEARS SUPPORTED BY A 904 AUTO WITH SHIFT IMPROVEMENT KIT. SUMMIT RACING AND CLIFFORD PERFORMANCE HAVE MOST EVERYTHING YOU NEED. THIS COMBINATION IS GOOD FOR ABOUT 39 MPG. THATS AN IMPROVEMENT OF 3MPG OVER STOCK. I HAD NOT ADDED IT BUT MSD WOULD LIKELY IMPROVE IT A BIT MORE. ...................................................HEMISIX
Author:  HEMI6 [ Fri Oct 26, 2007 4:22 pm ]
Post subject: 
NOW FOR PERFORMANCE TAKE A 225 PUNCH IT .40 , .10, .10, BORE, CRANK, BEARINGS. 10.5 TO 1 PISTONS, ELECTRONIC IGNITION WITH CHROME BOX AND MSD 6AL. GO FROM .10 AND .12 TO .22 AND .22 INTAKE AND EXHUAST LIFT. ABOUT A 273 CAM, BLOCK ACID DIPPED CLEANED OUT OIL PASSAGES. 4 BB 390 WITH ADJUSTABLE JET PACK. WHEN MOUNTING THE 4BB POINT IT TOWARDS THE FENDER AS THE STOCK CARB WAS SITTING THIS IS NOT A V8 DON'T BUILD IT LIKE ONE. YOU WANT TO SET UP YOUR TOTAL TIMING INCLUDING ADVANCE FOR 44 DEGREES TOTAL ADVANCE HOT RODS ONLY!! FOR THE TRANNY A HIGH STALL TORQUE CONVERTER AND A SHIFT IMPROVEMENT KIT. I HAVE YET TO FINISH A QUARTER MILE RUN THE ENGINE IS STRONG BUT I RIPPED TWO REAR ENDS RIGHT OUT FROM UNDERNEATH THE CARS AND MY ONLY STOPPING POWER COMES FROM THE FACTORY 9 IN DRUMS NO POWER BOOSTER. WHEN COMEPLETE WILL POST HOW WELL SHE DOES. DON'T WORRY TOO MUCH THEY WERE ONLY 7.25 REAR ENDS PUTTING A STRANGE 8.75 WITH 3.23. THIS SET UP STILL GETS ME 27 MPG WITH 2.76 GEARS AND A TOP END ABOUT 145MPH , YES THIS IS VERY SERIOUS. 843-906 6537 FOR THOSE INTERESTED IN MORE.
Author:  runvs_826 [ Fri Oct 26, 2007 4:29 pm ]
Post subject: 
$5000 is a boat load to spend on a slanter in my opinion which is good or bad depending on your goals. First, even with that budget it is hard to make the slant a showstopper, but can be done. If you got the mechaincs back I would defintley pull the engine and build it from the ground up that was so much better than simply adding a few performance parts. Send the head to the shop and get the deck shaved, port and polish, and send him some bigger valves. don't forget the 3-angle and hardened seats. The bottom end if you got the time to find some 198 rods I would recommend the long rod set-up, otherwise stock rods shot peened and balanced will be nice. Cam, lot's of cam. Last finish her up with the intake and exhaust, don't forget about the rear like I metioned, 3.55 are a nice balance of power and economy. I have changed out my 2.76's but my slant if dipping towards 14's on regular rods but same as above. A kid shouldn't need much more than that, cause I don't.
Author:  jskv12 [ Fri Oct 26, 2007 5:43 pm ]
Post subject: 
This is really a great forum. I am involved on several other forums involved with different cars I own but this one is a stand out for mechanical advice.
My car does already have front disc brakes and Crager SS 14X7 wheels with 245/60-14 TA's on board. They're from 1979 but still in order.
I am going to research some of the ideas shared here, all of which I greatly appreciate. I would love someone to ashare with me the downside to the Clifford "system" and a list of appropriate alternatives and where to look for them. This may already have been posted inwhich case I simply need the direction.
As I realize and has been so appropriately pointed out, it is not logical to spend a lot of dough on a /6 unless of course, as is the case with me, you have an emotional attachment and love for your car. The car will hopefully stay in the family as long as possible. Thanks again everyone and keep the advice coming!!

Jeff
Author:  HEMI6 [ Fri Oct 26, 2007 6:41 pm ]
Post subject: 
OTHER THAN THE COST THERE IS NO REAL DOWNSIDE TO CLIFFORD PERFORMANCE WHEN IT COMES TO THE SL6 NO OTHER MAJOR COMPANY COMES CLOSE, I HAVE AN ORIGINAL SET OF CLIFFORD HEADERS BUILT IN THE EARLY 70'S AND THEY WORK GREAT I DID HAVE TO MAKE A BRACKET TO SUPPORT THE OFFY INTAKE, BUT MODERN VERSIONS HAVE THE BRACKET INCORPERATED ALREADY THIS HELPS KEEPS THE INTAKE FROM CRACKING. THE FUEL INJECTION SYSTEMS SEEMS PRICEY BUT AFTER DAD INSTALLS HIS I WILL HAVE TO PASS THE WORD ON ITS AFFECTIVENESS THESE CARS CAN RUN 13'S AFTER MY REAR END COMES IN AND MY BRAKES ARE UPGRADED I WILL RUN IT. LATER HEMISIX, TRY LOOKING UP 245 OR 265 HEMI SLANT SIX
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