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At a crossroads and need some advice from the gurus
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Author:  shadango [ Thu Aug 18, 2016 4:52 am ]
Post subject:  At a crossroads and need some advice from the gurus
So for anyone following the saga, my son and I are are removing for the purpose of rebuilding our 1980 Volare's slant 6 after "something" recently came apart causing non metallic metal to flow through the oil pump, ultimately siezing it.

Now, I have been told "time for a HEMI!"......"time for a stroker small block!" and the like.....however, as much as I would love to do that, there are several factors right now ---- budget, time and practicality.

The car is my almost 17 year old son's first car.....so 300+ HP right now might not be the best thing to have at his newbie (though so far very responsible) fingertips. So thats the first issue.

Next is that this car will be year round to his work, school, etc. SO it has to be reliable, fuel efficient enough for him to be able to drive it and cold-weather friendly. I also want to feel safe with him driving it on the highways, where the new speedlimit on some is 70 mph. AND the kicker....we need to get it back together before the snow flies and the weather turns to crap here...sometime in late october or november usually.

The car came to us with all emissions stuff in place--- how well its functioning, no idea....but it is all there. Air pump, cat, all sorts of vacuum switches and doodads and a mile of emissions hoses. I would love to clean up under the hood because IMHO its a rats nest of goop that probably doesnt do a helluva lot for actual emissions. That said, we have to pass a VISUAL emissions inspection yearly.....so I assume that means all the emissions gear needs to be in place.

Still, since we are going through everything and having the engine redone , it seems like a great time to try and find a few extra ponies and fun for the boy.

So the question is -- what would you gurus here suggest as far as what can be done in the machine shop and during the engine rebuild to eek out a few more smiles per gallon AND miles per gallon while keeping the emissions goop all in place (as much as I hate thinking about reinstalling all of that!)?

Reading a multitude of posts, seems like milling the head to get a cr of "8 dynamic" is one favorite......I assume porting /polishing the head would be advantageous......what about the stock intake and exhaust manifolds? It only supports the stock one barrel which I know doesnt scream or even whisper performance......

So is there a route we can take in some "souping up" to keep the law, my son and my checkbook all happy at the same time?

Or are we better off to just go stock rebuild and put her back the way it was until at some point we can find a way around the emissions mess?

Thanks all!
Author:  Rob Simmons [ Thu Aug 18, 2016 5:09 am ]
Post subject: 
You're on the right track to keep the Slant 6 with a little upgrade while you're at it.

Milling the head and doing a little port/polish with larger valves will make a big difference.

There are also some good camshaft choices that will compliment the new head.

An upgrade to a larger carb and free flowing (larger) exhaust also helps.

My son's first car was a '74 Duster. :wink:

http://www.slantsix.org/forum/viewtopic ... t=kentucky

We didn't get as far along as we had planned before he wanted to move on to something more modern, but I'm keeping tabs on Stella and have first dibs if/when the new owner is ready to sell her back.
Author:  Badvert65 [ Thu Aug 18, 2016 5:40 am ]
Post subject: 
Definitely raising the compression will help. Find a Super Six 2 bbl setup and get bigger pipes for the exhaust (if you can). A 1980 might be a hydraulic cam engine so check that before you invest in a camshaft.
While you are at it, find out what your rear axle gear ratio is and increase the ratio if it is under 3. I think gears in the 3.2 range are a great balance between economy and performance. If you have something like 2.45 or 2.76 then you will be sacrificing performance to benefit economy.
I'm just sayin'
-Matt
Go Steelers!!
Author:  shadango [ Thu Aug 18, 2016 10:14 am ]
Post subject: 
Quote:
Definitely raising the compression will help. Find a Super Six 2 bbl setup and get bigger pipes for the exhaust (if you can). A 1980 might be a hydraulic cam engine so check that before you invest in a camshaft.
While you are at it, find out what your rear axle gear ratio is and increase the ratio if it is under 3. I think gears in the 3.2 range are a great balance between economy and performance. If you have something like 2.45 or 2.76 then you will be sacrificing performance to benefit economy.
I'm just sayin'
-Matt
Go Steelers!!
Thanks -- How would the SUper Six setup tie into the emisions, though, if at all? Super Six was from earlier models right?

According to what I have read, 1980 was the last year of the adjustable rockers...then they went to hydraulics.
Author:  jcc [ Thu Aug 18, 2016 11:32 am ]
Post subject: 
A 17 year old will increase his driving skills exponentially with proper guidance. Any engine will reach a speed dangerous enough to cause harm to himself or others. A slant six IMO is for those who remember them when their mom had one, and have another car already with a starter with more horsepower.
The point being, on any kind of budget, any 17 year old will quickly get bored with its power level, it will not satisfy ANY peer pressure issues, or the lady's. I say drop in a good running stock 318, find them a dime a dozen, bolts almost right in, and then let him hop it up as his mechanical skills grow, and budget allows, there is a lot more potential there if he chooses. and a stock 318 will leave almost any slant in the dust. I know this is a slant site, but we are talking a 17 year old here, not a person collecting SS. Its what is in his interest, not ours, that I make the above comments.
Author:  DusterIdiot [ Thu Aug 18, 2016 4:51 pm ]
Post subject:  A few thoughts....
I guess you should define a tight budget to see what you have the potential to do and not do.

You are correct, if it is the original engine for the car then 1980 model year is the last year for mechanical lifters in the cast crank engine.

I would also come to an understanding of what will be required by your emission and inspection laws... here in Oregon, those urban areas that require it, bring up pictures on their terminal during the visual inspection before for the idle tail pipe test... and the run the VIN... if your state has the same procedure then swapping in and engine that doesn't match the VIN (5th digit - C for 1 barrel, D for 2 barrel 6 cyl usually) typically causes a fail.

I will assume that the primary purpose of this car will be: somewhat reliable transportation, has to be able to be maintained on a very limited budget, allowed to be used to teach basic automotive maintenance and mechanics, simple enough to learn and work on, is not primarily to be aggressively driven, not to be a status symbol, not to get tickets a lose insurance for road racing or going light to light....

If you mean to keep the car and are on a tight budget, I'd look around and see if anyone has a good spare 225 they are letting go for a reasonable price (you can also price out a reman engine to see what that cost is to compare and bargain with...).

Hopefully you could find a decent 1968-1980 225 slant six, and transfer your equipment over to it.

On options:

If spending other money on additions:

"Bolt" on mods that will increase power, acceleration, etc...

Installing a 1976-1980 FMJ rear axle with 3.23 (7 1/4"- 9 bolt cover), or 3.21 (8 1/4" - 10 bolt cover) will help get the heavy car motivated sooner... You will also need to swap in the speedo gear from the donor... and if swapping from one axle type to the other, you will need the driveline from the donor car. Which cover do you have? polygon shaped 9 bolt or oval 10 bolts?

Super Six... finding a complete OEM stack is getting a bit harder and is somewhat expensive... but these are from 1977+ so they have all the emissions stuff you need to pass the visual check... this will net a bit more power, especially when paired with the larger super six exhaust, and you will have to check the part number on your current distributor to see if you have the 'federal' distributor (same as 1 barrel and 2 barrel in the very late 70's)....

A rebuild is going to be some $$$ (engine rebuild kits are $400-600 depending on what is included in the kit....)

If you decide on the rebuild, some milling to the head and deck will be required, it is good to increase the compression some, you don't want to go crazy (some of this also depends on tailpipe emissions testing if you need to remain stockish...or go to the 9:1 level).... Oversize valves aren't needed if the engine is going to be in the stock range and you stay with the stock 1 or 2 barrel... it does help a bit to clean up the ports with a die grinder.... if you won't be doing a tailpipe test, then you might also consider sending your cam shaft in to Oregon Cam grinding for one of the RV!0DP profiles.


I would say ball park figures (and depends on legality):

Prices in my neck of the woods would be in the ballpark of:

Running Craigslist slant six - $150-$500
Running possibly smoking junkyard slant six - $350
Running may be high miles 318 and A904 transmission - $300-$500

318 transitional motor mounts for spool mount K member - $150+/-
New transmission lines $100+
318 exhaust - fabbed not scavenged - single outlet - $400+

Super Six 'stack' with kick down $200-$500
3.2x rear axle (junkyard/craigslist) $150-$350 (or possibly more with a sure grip unit)

You might get lucky and someone local may have a lead for you, you might get lucky at a swap meet and find some items at a bargain...


Just some things to think about along with your budget and intent.
Author:  Badvert65 [ Thu Aug 18, 2016 7:36 pm ]
Post subject: 
Just an FYI, the FMJ body cars (Volare) will either need conversion motor mounts (Schumacher) with the slant 6 K frame or will need to swap to a V-8 K frame - if going the V-8 route.
Author:  Jerame_c [ Sat Aug 20, 2016 12:08 am ]
Post subject: 
I had a 1980 Plymouth Volare 4Dr with the slant six, all the emissions junk, and a single barrel carb. It rolled 80 on the freeways in the southern Oregon mountains effortlessly and in the late 90's was faster than most poor college kids cars. (not to mention it seated 6+ and slept 4)
To stay legal and enjoy that car a lot I suggest:
Make sure the kickdown is adjusted, this makes a huge drivability difference.
Run lighter advance springs (based on what the emissions test will let you get away with)
Larger exhaust, and the super six exhaust manifold (looks the same basically on the outside but has a larger diameter)
Raise compression. My current slant is 9.1:1 static with a stock cam. (this might be too high for the fuel distribution of a properly tuned carb on a stock type intake manifold, ask around)
Do a basic port cleanup and a manifold and head to gasket port match.
(I really like the stock metal gasket for this as its ports are just slightly smaller than the current squishy kind and doing the grinding with it in place protects your engine parts if you slip.)
Lastly is two things for fuel mileage.
Reduce weight anywhere you can and lower the front of the car a bit.
bringing the front of my duster down got me a couple miles to the gallon on the highway to get me the last bit I needed to cross over the 30mpg highway mark. (don't expect to get to that, the multi-port fuel injection is a large part of my fuel savings)

Lastly consider how often you have to do an emissions check and how much effort it would be to change around a few things between each test.
If you are good with that I would suggest a different intake (or a modified one) to run a staged two barrel like the webbers as this should boost both fuel economy and power compared to the stock single barrel. (and likely reduce real world emissions)
Author:  shadango [ Mon Aug 22, 2016 8:07 am ]
Post subject: 
This is all great advice guys, thanks.

I have been looking for a slant 6 in my area and so far not much luck....at least not one that us running and late 70s or 80.

ALso havent had luck finding a super six setup. :(

Gonna keep looking.

The v8 swap is a "one day" thing....for now the slant 6 is gonna be our route.

I have located a shop or two that will rebuild for in the $1500-3000 range......a crate from autozone comes in at $2k but a) its bone stock and b) who knows what kind of quailty I will get....and then have to deal with a faceless big company.

Is there a hot spot as far as finding parts for these slant 6s? Cam, pistons etc? I want to be able to direct my buiklder somewhere if he runs into isues finding a source......because frankly I dont think slant 6s are very common anymore as far as people building them up...unlike a chevy 350, I am sure there will be somewhat of a learning curve for many builders .... I would prefer to go to a builder who has a vast experience base souping up slant 6s but lets face it, the slant 6 has never been a main stream "soup up " kind of engine....which is one reason I kind of love the concept to begin with. LOL
Author:  shadango [ Tue Aug 23, 2016 6:12 am ]
Post subject: 
Doing a quick search, Summit comes up with the comp cams kit K64-240-4 --- includes a cam (252 adv duration, .435 lift), double roller chain and gears set, valve seals, lifters, locks and springs.

$309 and in stock

Does this sound like a good setup? They also offer a .440 lift but that is probably too much I figure....(what IS the stock lift/duration?)

Hughe's cams offers separate items --- 3 diff cams .... "whiplash" cam 108 degrees plus 5, then a 112 degree plus 4 cam.....
Author:  Joshie225 [ Tue Aug 23, 2016 7:40 am ]
Post subject: 
Not a great cam and it DOES NOT come with a roller timing set. The Hughes cams are ground backwards from what a /6 wants which is more intake duration than exhaust duration. If you're doing a conservative build with emissions a consideration the Dutra RV10-RDP is an excellent choice which works well with new stock valve springs. See this post from Dan: http://slantsix.org/forum/viewtopic.php ... cam#439664
Author:  shadango [ Tue Aug 23, 2016 8:43 am ]
Post subject: 
Quote:
Not a great cam and it DOES NOT come with a roller timing set. The Hughes cams are ground backwards from what a /6 wants which is more intake duration than exhaust duration. If you're doing a conservative build with emissions a consideration the Dutra RV10-RDP is an excellent choice which works well with new stock valve springs. See this post from Dan: http://slantsix.org/forum/viewtopic.php ... cam#439664
Cool....thanks!

Will I have to choose one grind over another to address whether we go stock single barrel or super 6 two barrel?
Author:  Joshie225 [ Tue Aug 23, 2016 11:16 am ]
Post subject: 
A Super Six intake and 2 1/4" exhaust helps with a stock cam and will work beautifully with the RV10-RDP. Make sure that you or whomever installs the cam checks the installation with a degree wheel and corrects the installed centerline as needed.
Author:  shadango [ Tue Aug 23, 2016 11:58 am ]
Post subject: 
Quote:
A Super Six intake and 2 1/4" exhaust helps with a stock cam and will work beautifully with the RV10-RDP. Make sure that you or whomever installs the cam checks the installation with a degree wheel and corrects the installed centerline as needed.
SO the RV15 is not needed for two barrels?
Author:  Joshie225 [ Tue Aug 23, 2016 12:12 pm ]
Post subject: 
No. The RV15 requires a bit more compression and is less likely to play well with emissions systems.
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