225 slant rebuild for more power

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Keep your slantsix basic and stock. Don't go installing speakers, amplifiers, and rewiring add ons until you know more about the electrical capabilities and inherent weaknesses in the stock wiring. There are some people on the Slant Six Forum who know some things. I'm saying this because you are very young and might want to be tempted to add this stuff too soon. Good luck with your '64 Valiant. Nice car.
 
Thi
Pull the head, Mill it .100 thousands if it has never been touched, that will get you to 9:1 area But measure piston deck height to get in the ball park and cc heads,

clean up the head while you are at it carbide bit off amazon less than 20 bucks port it out a bit just smooth out any casting flaws dont go crazy add 340 springs,

get some split exhaust manifold or run a 2.25 exhaust head pipe under you stock manifold

recurve that distributor swap over to electronic ignition

super six it but get ready to redo the whole linkage and kick down also need a early v8 gas pedal assembly

Send your camshaft to oregon Cams get a regrind or pick out something for torque cause you got a heavy car.

Should have a nice cruiser while maintaining MPG and adding HP[/QUOT
Welcome to the club.
I completely rebuilt the 225 in my 64 Val because it was locked up when I got it. Following recommendations here I did the following:

Milled head 0.080 but you should consider going 0.100. As Charlie says, no downside, big upside. Modern head gaskets are at least 2X thicker than the original steel shim gasket so you'll lose a little compression. I did a complete rebuild do had my machinist install hardened exhaust seats with valve job. I did a little pocket porting and gasket match because it was only my labor, free!
Block bored .040 over with Silv-o-lite pistons and moly rings.

Sent the cam to Oregon Cam grinders to be reground. Talked to the owner and he recommended 2 grinds and I went with the milder because it's a driver. I'd say it's between 318 and 340 specs.

Did a little porting on the stock exhaust manifold and gasket matched, free labor.

Rebuilt the stock BBC carb. Advance timing to 10* BTDC.

Anyway, it drives great. Never feel a need for more when driving. Best ET was 18.4 secs. Got almost 24 MPG going to Carlisle. Have about 8000 miles on it and haven't touched it.

You can do less and be fine. Since you are taking classes, disassemble completely, new timing chain, maybe hone and re-ring, check bearings, oil pump, etc. and inspect everything. Dyno proven that biggest increase in power is going to 2 barrel carb.

You need to read this section and check out slantsix.org
Disregard the haters who say V-8.
Alright couldn’t have asked for a better explanation from you guys. I have a daily truck so I’m in no rush to get this motor going

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Step 1 complete now going to disassemble tomorrow and than going off to a machine shop this is my present this year merry Christmas you guys thanks for the help
 
Step 1 complete now going to disassemble tomorrow and than going off to a machine shop this is my present this year merry Christmas you guys thanks for the help

Can we get some good pictures of the car? I assume it's the one in your avatar?
 
You don't want a high volume oil pump in a slant. Best to either use a stock volume pump, or a stock volume pump with a high pressure spring, but not the high volume.
There are a several items on that list that have a poor benefit to cost ratio,,,
The Mallory distributor, no vacuum advance,, expensive,,
Just get a stock slant electronic distributor, re curve it as necessary, run a HEI ignition.

The replacement rods and pistons,, again a lot of expense, useful in an all out race engine. But lot of folks have ran turbo power boosted slants using stock rods and pistons without rod or piston issues.

head and main studs,, again all out race engine stuff

are just a few of them.
I agree with keeping your first build basic,
Raise compression, basic bowl work, new timing chain and bearings,,,,
 
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There are a several items on that list that have a poor benefit to cost ratio,,,
The Mallory distributor, no vacuum advance,, expensive,,
Just get a stock slant electronic distributor, re curve it as necessary, run a HEI ignition.

The replacement rods and pistons,, again a lot of expense, useful in an all out race engine. But lot of folks have ran turbo power boosted slants using stock rods and pistons without rod or piston issues.

head and main studs,, again all out race engine stuff

are just a few of them.
I agree with keeping your first build basic,
Raise compression, basic bowl work, new timing chain and bearings,,,,

I agree with all of your points as well. The oil pump just stuck out to me, not because of cost, but because that's a major weak link for the slant six. Using the high volume oil pump greatly increases the possibility of camshaft gear and or oil pump gear failure. It's just not a great idea.
 
I run high volume oil pumps on my slant , and already reused it on two camshafts on the same motor in my dart no problems 50 psi cold 45 warm. Although I would not run comp cams slant six camshafts, I have a slant im building that broke off the oil pump gear straight off the camshaft.
 
I run high volume oil pumps on my slant , and already reused it on two camshafts on the same motor in my dart no problems 50 psi cold 45 warm. Although I would not run comp cams slant six camshafts, I have a slant im building that broke off the oil pump gear straight off the camshaft.

You got lucky. Don't steer him in a possible wrong direction here. There have been LOTS of problems regarding this. This article is just the tip of the iceberg.

Title

To the OP, run what you want, but you'll not see me run an HV pump in a slant.
 
You got lucky. Don't steer him in a possible wrong direction here. There have been LOTS of problems regarding this. This article is just the tip of the iceberg.

Title

To the OP, run what you want, but you'll not see me run an HV pump in a slant.

I agree AND the 225 is a low rpm engine anyway. (4-1/8 stroke) 4500-5000 and you're done.
There is s lot of info on slantsix.org sbout this.
 
I agree AND the 225 is a low rpm engine anyway. (4-1/8 stroke) 4500-5000 and you're done.
There is s lot of info on slantsix.org sbout this.

Exactly. That's one reason why I think.....although I am going to do it, head porting isn't terribly critical. Sure it will add to......and Lord knows every bit helps, lol, but the long stroke lends itself to low RPM torque.
 
The motor is in the bed of my truck gonna take it to a machine shop after Christmas. I want to run a different cam so I’m looking for stronger valve train anybody have a link to a good kit to use and any recommendations for a more torquey cam. Going to deck the block shave the heads but run same piston assembly with new rings. I’m debating whether to go 4 or 2 barrel as well. Machine shop said $1k for complete job with a fresh Chrysler red paint job. But will need to give them the cam and valves everything else is included.
 
I’m 17 years old and taking auto classes through my school. Tomorrow we’re pulling the 225 slant out of my 64 valiant wagon. I need some more power out of it and don’t really know where to start. Going to see how much it will be to send it out to the machine shop but would rather not go through that. I’m thinking the 2 barrel manifolds and carb if I can find those and some new valve seats and what not. It runs good how it is but need to do all the gaskets and manifolds anyways got leaks everywhere. Looking for your guys recipe for a more powerful slant that is still a good runner. I’m located in LA if u guys know any machine shops in so cal.
 
I have a 67 Valiant, things I have done to mine: I installed 2-1/2 inch exhaust from the stock header to the muffler with a "Y" pipe in the front of the muffler and electronic cutout. Doesn't go any faster, but makes a lot of noise, good for parades. From the muffler to the rear bumper a 2-1/4" pipe. I have a 72 engine super six and Transmission, I rebuilt the trans myself and installed a shift kit in it. I installed a 75 "K" member with 75 lower control arms so I could put on a sway bar. I installed .89 dia. torsion bars, in case I ever install a V-8. I installed new gas powered shocks. When I bought the car, the rear fenders were already tubed 3" on each side. I put in a narrowed 8-3/4 rear end with 3.55 sure grip. I have another 3rd member with 2.93 sure grip for highway driving. When I bought the car the person I bought it from had installed 79 Volare disc brakes in front and 79 drums in the rear (10X2-1/2"). it really stops good. I have 15" slotted mags all around even the spare, 4-1/2" right hand bolt pattern. 235X50R15's on the front, 295X50R15's on the rear. There hasn't been anyone so far that can beat me across the intersection, V-6's and V-8's. Very quick off of the line and no tire spin, however when it goes into 2nd gear it chirps the tires. I have high back bucket seats and center arm rest out of a 2000 Dakota. The only 67 Valiant that I know of with 8-way power seat. I installed a electronic FM radio with blue tooth, USB and SD card for music. I have a 74 Duster seat for the rear seat. Just a fun car to drive
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I have a 67 Valiant, things I have done to mine: I installed 2-1/2 inch exhaust from the stock header to the muffler with a "Y" pipe in the front of the muffler and electronic cutout. Doesn't go any faster, but makes a lot of noise, good for parades. From the muffler to the rear bumper a 2-1/4" pipe. I have a 72 engine super six and Transmission, I rebuilt the trans myself and installed a shift kit in it. I installed a 75 "K" member with 75 lower control arms so I could put on a sway bar. I installed .89 dia. torsion bars, in case I ever install a V-8. I installed new gas powered shocks. When I bought the car, the rear fenders were already tubed 3" on each side. I put in a narrowed 8-3/4 rear end with 3.55 sure grip. I have another 3rd member with 2.93 sure grip for highway driving. When I bought the car the person I bought it from had installed 79 Volare disc brakes in front and 79 drums in the rear (10X2-1/2"). it really stops good. I have 15" slotted mags all around even the spare, 4-1/2" right hand bolt pattern. 235X50R15's on the front, 295X50R15's on the rear. There hasn't been anyone so far that can beat me across the intersection, V-6's and V-8's. Very quick off of the line and no tire spin, however when it goes into 2nd gear it chirps the tires. I have high back bucket seats and center arm rest out of a 2000 Dakota. The only 67 Valiant that I know of with 8-way power seat. I installed a electronic FM radio with blue tooth, USB and SD card for music. I have a 74 Duster seat for the rear seat. Just a fun car to driveView attachment 1715441597
That’s a bitchin ride don’t know much about rearends and gearing and what not but just takin it one step at a time.
 
The motor is in the bed of my truck gonna take it to a machine shop after Christmas. I want to run a different cam so I’m looking for stronger valve train anybody have a link to a good kit to use and any recommendations for a more torquey cam. Going to deck the block shave the heads but run same piston assembly with new rings. I’m debating whether to go 4 or 2 barrel as well. Machine shop said $1k for complete job with a fresh Chrysler red paint job. But will need to give them the cam and valves everything else is included.

The condition of the bores will tell you (actually your machinist) whether you can keep your pistons or not. If the bores are excessively worn or scored, you will need an overbore to clean up. If you are lucky you may be able to get away with just honing, new rings, bearings.

Look up Oregon Cam Grinders and either send them an email or call them directly. You give them your details on what you have, gear rario, transmission, how you are going to use the car, etc. and they will recommend a couple grinds. Don't go crazy on the cam, too easy to go wild and kill the driveabilty of the car. For about $100 you send them your stock cam and they regrind it to gain power/torque. It will require new lifters (which they have) and probably a valve spring upgrade. Stock 318 or 340 springs are an upgrade over the weaker slant springs. Again, no need to go wild, a stiffer spring requires more engine power to open them and too stiff isn't necessary on your low rpm engine.

Being a young guy and all, you might go to Amazon and look up and buy the book written by Doug Dutra. (Doctor Dodge) He pretty much took all his knowledge and wrote THE book on slants. (SlantSixDan) is one of the contributors. I don't think Doc put all his speed secrets into the book as very little content is actually devoted to racing.

I would recommend concentrating on getting a good, solid, reliable engine in the car and drive it for awhile. It will tell you if anything is lacking. Don't be surprised if just driving around in that car is cool enough for you.
 
You don't want a high volume oil pump in a slant. Best to either use a stock volume pump, or a stock volume pump with a high pressure spring, but not the high volume.


I never had any problems with it, and the guy I sold it to didn't have any problems either ! Nor did I have any problems on 2 previous builds !
 
I run high volume oil pumps on my slant , and already reused it on two camshafts on the same motor in my dart no problems 50 psi cold 45 warm. Although I would not run comp cams slant six camshafts, I have a slant im building that broke off the oil pump gear straight off the camshaft.
I’m looking for an intake right now I’m thinking Aussie speed long runner 2 barrel and Holley 350 avenger. I think this will be a good combo for the regrinded cam new lifters and 318 springs. Going to deck the block shave the heads and new rings and bearing hopefully I can use the same pistons they haven’t got back to me yet. I haven’t even thought about carbs and linkage yet but I know jack about carbs so please hit me with some knowledge thanks guys hope you all had good holidays.
 
I’m looking for an intake right now I’m thinking Aussie speed long runner 2 barrel and Holley 350 avenger. I think this will be a good combo for the regrinded cam new lifters and 318 springs. Going to deck the block shave the heads and new rings and bearing hopefully I can use the same pistons they haven’t got back to me yet. I haven’t even thought about carbs and linkage yet but I know jack about carbs so please hit me with some knowledge thanks guys hope you all had good holidays.
Intake i would say super six or offy four barrel intak, kickdown and throttle cable will also need to be redone early veight darts barracuda valiants or slant six would have the throttle cable pedal that bolts in your wagon
 
Intake i would say super six or offy four barrel intak, kickdown and throttle cable will also need to be redone early veight darts barracuda valiants or slant six would have the throttle cable pedal that bolts in your wagon
I just love the look of those long runners especially on a wagon like mine. Debating whether to go eddy 500 cfm or Holley 390 either on Aussie long runner or Offy intake.
 
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