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Old 05-30-2014, 06:52 PM
ronstory ronstory is offline
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Default 1964 Catalina convertible 400 engine upgrade – need help on options

All—

I have the 1964 11H engine which is the 389 10.5CR 267HP and 2bbl and a 2.53 axle, which got 19 mpg on the 300 mile adventure filled bring-it-home journey back in July’13. lol

I’ve ditched the slim jim and put a 700R4 that is built to the max plus 3.42 gears so I have 2.39 overall gearing in overdrive. I just bought a 1974 400 block out of a firebird and I’m looking to make a fun to drive convertible with more power at speed and still be able to surprise a few rice-rockets at traffic lights. I’d also like to get 16mpg or better on the highway.

Background: In 2002 I build a Factory Five Cobra replica and at the time the Comp Cams XE series fat-lobs were pretty new and it worked amazing in the Ford 331 I made out of Lincoln 5.0L with the ported Trick Flow twisted wedge heads. The reason I went with the 331 and not a stroked Windsor 351/427 motor was that every FFR with a 427 I drove could not put the power to wheels and have the tires stay connected to asphalt. With my setup and 3.23 gears and sticky 275 tires, the car launches like a banshee and it has been clocked at 0-60 at 3.6 secs. Scary fun and I’m glad I got my IMSA license back in 1992-93… or I would be dead by now. That 90 inch wheelbase and 425+HP makes for squirrely times. ;^)

So I’ve already got a car that I can take to a drag race, now I’m looking for is a fun cruiser that can pull away on the freeway, will have lots of torque but not so much I’m tire limited. I’m running 255 BFG back tires right now so I’m OK spinning the wheel at launch but would prefer not have major traction issue ‘down the road’. The big question is what do a build with the 400?

The 400 was a kit (it was in pieces) has been rebuilt once to +0.030. There is little wear but a bit of surface rust on a couple of cylinders and the same for 0.010 ground crank. The rods are stock and pistons are the cheap cast 8 brow versions. I’ve dropped if off at my engine builder and he is a perfectionist so we’re looking at a 0.040 rebore/hone and maybe a reground on the crank. I’ll get forged rods and new forged pistons.

So I’ve got two options:

1. build a 408 using the stock crank or aftermarket crank with the 3.75 stoke.
2. Get a 4.0 stroke rotating assembly and build a 434. I’m pretty sure a 4.25 stroke will be “too much” 

It will be easier to meet the mpg target of 16 or better with the 408 but I’m not sure it have enough torque to really move the 3900lbs of metal. The 389 is “not bad” in its current form but it’s certainly not impressive. On the other hand I’m concerned with the 434 option that I’m going to be tire limited since the selection of sticky 15” tires is limited to mostly drag radials and I’m more of a corner carver at heart.

I’ve got a good working Edelbrock 1904 (Quadrajet clone) and I’ll get a build kit from Cliff R (I already bought his book).

The engine came with two sets of heads, 4X-1H and 6X-8 that has been upgraded to 1.77 exhaust valves. I’ll CC them this to see if they have been milled, but I’m not sure I’ll be able to get good enough compression to get some reasonable gas mileage. Worse case I can get a set of KRE aluminum heads, since Tin Indian seems to have best price for the basic head that ‘only’ flows 250-260 CFM since I don’t think I need 290/310+ upgrades.

Any opinion from the experts on whether a 408 will be fine or should I spend the additional bucks on 434? I’ve only been a Pontiac owner for 10 months so I’m still a newbie.

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Ron
1964 Catalina ragtop
  #2  
Old 05-30-2014, 08:39 PM
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MrWrestlingII MrWrestlingII is offline
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How much does your car weigh? The reason I ask is, I'm running a 4.25" crank in my 70 gto and it's not too much. I would think your car would weigh as much or more. I'm got 3.42.gears with 28" rear tires, so the final gear ratio is in the 3.20s, if I stay out of the secondaries I can get 13 or 14mpg with a m20. My setup is very streetable and allot of fun to drive.

If you have the budget I would recommend the larger crank with a forged rotating assembly, SDs stump puller cam, properly set up heads with a static compression ratio of 9 - 9.5 :1, cliff spec'd qjet and 2.5" exhaust.

It's a proven combo that many are running here.

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1970 GTO-vert, 461, eheads, stump puller, m20, 3.42
  #3  
Old 05-30-2014, 09:30 PM
ronstory ronstory is offline
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Your car is roughly 3650lbs and mine is 3845 (courtesy of oldride.com). Any idea how much torque you have in your 461?

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Ron
1964 Catalina ragtop
  #4  
Old 05-30-2014, 10:27 PM
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I've never been on the dyno but I would expect it to be 500 - 550.ft lbs. This is a good combo for a heavy car with streetable gears.

What ever you decide to go with, pay attention to every detail of the combination.

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1970 GTO-vert, 461, eheads, stump puller, m20, 3.42
  #5  
Old 05-31-2014, 12:36 AM
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Our 65 2+2 weighed in at 4,246 with driver and half tank of fuel when we had it weighed for the HPP shootout article, and I'd bet the '64 convertible is at least that heavy.

You really have two problems to solve. One is the 2.39:1 effective final drive ratio that is going to limit your cam choice, or more precisely how large of cam you should be running. Up the duration and your cruising sweet spot could end up being 85+ MPH. So this calls for a milder cam to get some use out of 4th gear.

Next problem is the lower ratio 1st gear in the 700R4 is good for roasting tires. Your effective first gear ratio is roughly 10.5:1 which is low enough on the street to fry the tires regardless of engine choice. Getting a cam small enough to allow overdrive cruising is going to put a lot of torque down low on the engine RPM. We have 3.42 gears in the 2+2 along with the 421 with the 4" stroke and RAIV clone cam which should be killing some of the bottom end torque. First gear ratio with the T400 is 8.2:1and we still have to roll on the throttle on the street.

If your '64 is like our '65, the wheel wells are relatively small -- an inch smaller in width than the A-bodies from the same period, and this is going to limit your tire size somewhat.

So what would I do? I'd figure that off the line traction was hopeless even with a well built 400, so I'd live with that. I'd go with the 4.25" stroke, 9.3:1 compression, and a hydraulic roller cam no larger than 222/228 @ .050" on at least a 112°, and pushing .560" to .580" lift. Then I'd do my best to catch the competition at about 25 MPH in second gear...

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  #6  
Old 05-31-2014, 01:55 AM
ronstory ronstory is offline
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Mick--

Thanks for all the input. I didn't think about the low axle gear keeping me below the torque curve on the engine. The tire size I have in now is a BFG 15" 255 (28" high)... and you are right, that's about all the tire I can stuff in there and be assured of no rubbing.

With a 28" tire, it makes about 600 revolution per mile. So with 3.42 it will be ~2000 RPM at 60mph in Drive/3rd gear. With the 0.70 overdrive it will be about 1400rpm at 60mph. The current 389 seems to chug along just fine at 60-70mph, but when you drop a gear to pass, it does not pull well when it lands at 2000-2300rpm. Don't get me wrong, it still accelerating, but more like a rental car.

So it looks like I need a combo that will get decent gas mileage at the 1400-1600 rpm, but have plenty of power when it drops out of overdrive and lands at 2000-2300 rpm.

Is it that simple? (I'm thinking not )

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1964 Catalina ragtop

Last edited by ronstory; 05-31-2014 at 01:56 AM. Reason: typos
  #7  
Old 06-01-2014, 02:08 PM
dmac dmac is offline
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Sounds like you want the same as I do with my firebird 350. I am planning on stroking it to a 4.21 or 4.25 stroke, which will give it a lot of lower end torque, which I will need because I am sticking with the stock 2 bbl intake, and a 2 bbl carb for originality. But my firebird is a lot lighter than your car.

I am trying to build mine for a broad, flat torque curve but don't care if it can't hit 100 mph, as long as it pulls strong all the way.

I will be watching this thread.

  #8  
Old 06-01-2014, 03:26 PM
ronstory ronstory is offline
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This got me thinking of one of the best engines I've owned, the International Harvester 345. The torque curve varied only 3-5% from 1600 to the 4000 rpm redline. The only time you downshifted was if you dropped below 1500 rpm since you started to lose the torque. I've never had a 4spd vehicle that I have shifted less.

Then I got carried away and upgraded the engine to an IH 392, zero balanced (too a ton of Mallory metal) and better cam/lifters, cut the head to get 8.2CR and port matched 4bbl. It now revs to 6000 rpm pulling the whole way. But I miss the drivability of the original 345.

BTW, the best comment I ever got form the passenger seat with the new 392 was after we blew away a very surprised ricer-box at a stop, "Ron, nothing this big should ever move that fast".

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1964 Catalina ragtop

Last edited by ronstory; 06-01-2014 at 03:27 PM. Reason: grammar
  #9  
Old 06-01-2014, 09:50 PM
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OK, the engine came with two sets of heads, 4X-1H and 6X-8. I just CC'd the heads and The 4X heads were the most consistent at 112-113cc across the 4 of the 8 combustion chambers.

The 6X are another story. They have been upgraded to 1.77 exhaust valves and the chambers measured out at 108 to 105 on one head and 107 to 104cc with 105-106cc being the average. The data I can pull from the web looks like they 'should be' 100.3cc. Also there are machinist marks in the corner of each with a 002 and 006 likely indicating they the been machined. Also the head marked 006 averaged about one CC lower that the other head so those marks may be how many thousands were milled.

If I mill them say 0.045", that would remove about 9cc , the would get the heads back to the 95-99cc range. Using an average of 97cc, that means with 408 build I get a wimpy 8.5CR. If I do a 434 I'll get a 9.0CR and 461 will get 9.4CR.

Basically, my take is these heads are a no-go if I head the 408 direction, which means the cost I save from buying a complete stoker rotating assembly just shifts into KRE aluminum heads with 85cc chamber for a 9.4CR, unless I get them milled. But aluminum heads *are* cool.

With the 4cc variation between the chambers per side, are they worth keeping for a 434/461 build? I'm heading into uncharted territory here... so opinions welcome.

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1964 Catalina ragtop
  #10  
Old 06-02-2014, 01:53 AM
dmac dmac is offline
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Mill that much and you will be very close to fitment issues with the intake- and that will require more work on the intake. I see heads for sale all over craigslist. If budget is the issue, find a pair of heads that will work, rather than trying to force a square peg into a round hole. Save a little money on the rotating assembly by finding a used 455 crank instead of a brand new one.

OR

get pistons with a small dome, and achieve the cr you want. I'll bet you everything I own(not much) that a set of domed pistons will cost you less than a set of aluminum heads.

OR

think about a lower compression 464. even a low compression 464 will give you a lot more than the motor you originally had. At the rpm range you are talking about, you can build it for a little more rpm to make up for the lower CR.

Instead of maybe 170 HP at 1600 rpm, w/500 lbs of torque, you could make that same 170 HP at 1900 rpm with lower compression and 475 lbs of torque..

Those hp/torque/rpm numbers I used are just made up to make the point. Building these motors is always a trade off between the possible, the reasonable, and the budget. Going from 8:1 cr to 9.5:1 is like a 7% difference in power, if some estimates are to be believed, maybe less. Another option is to take as much material as you need to from the chambers in the heads to even them out if needed, without more milling, use a thinner head gasket, and work with what you have.

You started out saying you wanted decent fuel economy, but the 'cool' aluminum heads are turning you to the dark side. You will never save enough on gas to pay for the extra money you are budgeting for the heads. That big stroker 464 will suck more gas just due to the fact that it moves more air with each revolution, and the basic aluminum heads are not designed to run optimally at the lower rpm range you cited, as far as port size, valve size.


Last edited by dmac; 06-02-2014 at 02:09 AM.
  #11  
Old 06-02-2014, 10:25 AM
ronstory ronstory is offline
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Mick--

I have been looking for set of 6x-4 heads for last two months locally with no joy. The best price is I've seen on ebay was $550 fw/ shipping or a set of rebuilders that were mag'd for cracks and cleaned up.

i'm going to CC them again because I think when machinist milled them he may not have set them correctly in a jig. Both heads varied left to right 3-4 CC, with the left side being larger on both. I'll measure all the chambers to see if there is linear pattern left to right.

If I mill the chamber face, can't I also just mill the intake side the same amount to keep the intake bolt hole alignment correct? I wouldn't do that on SBC since the intake also seals the lifter valley and then you need to mill the bottom edge of the intake, but with the separate valley cover, that makes it easier.

As far as going lower compression, will that reduce my chances of getting reasonable efficiency out of the engine? I'm trying for 16mpg or better on the highway... and understand the cubes don't help.

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Last edited by ronstory; 06-02-2014 at 10:49 AM. Reason: typos
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Old 06-02-2014, 11:26 AM
dmac dmac is offline
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I might be lucky to be within driving distance of something like 30+ million people here in California's central valley. 6 hour to L.A., 2 hours to the Bay area with something like 8 million, Couple hours to Sacramento, then there's Vegas, Reno, and even San Diego and Portland Oregon are only ten hours away. I often see complete motors I could drive and pick up for what heads plus shipping cost you.


The only problem with milling the intake is that it won't be interchangeable but if you are satisfied with your choice, it will work. Besides, intakes are relatively throw away items when compared with buying/building new heads.

And you can still adjust the compression with pistons, no matter which heads you decide on, if you are rebuilding anyway. That would be my choice before cutting the heads any more.


Last edited by dmac; 06-02-2014 at 11:55 AM.
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Old 06-02-2014, 12:34 PM
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FWIW- for the build your looking at there's no performance gain between aluminum and iron heads, so it really comes down to $$$. If you've got a set of iron heads that can be setup properly at a reasonable price that's the way to go. I wouldn't compromise on the compression ratio, depending on the cam choice you'll most likely want to be close to 9.5:1. Shaving the intake is nbd, just be aware it may need to be done.

As Mick stated, your cam choice will be a compromise between 1st gear and overdrive. When I first got my current build on the road I was running old BFGs and was breaking the tires loose thru 3rd gear even before the tune was dialed in. I'm currently running Cooper Cobra's and they're allot better, which surprised me. That's not to say I can't easily over power the tires, but with some finesse I can get some power to the street. If you don't run RWLs the Maxxis MA-S1 Marauder has an H rating, which should be stickier that the BFGs or Coopers, I was going to try them but wanted a RWL tire so went with the Coopers.

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Old 06-02-2014, 01:07 PM
ronstory ronstory is offline
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Or Pontiacs are more rare in Portland.

I just CC'd the heads doing but I'm using a stopper not a sparkplug so the end sits below the surface of the chamber so that likely a CC extra. I also did a better job cleaning the surface to mount the plexi to the chamber.

6X-8
Mark Left CC spark bottom Right CC
002 107 105 104 104
006 106 104 104 103

So it looks like a still have ~3cc variation left to right. Is that typical?

As for having to modify the intake... I'm fine with that, they are cheap and once I get working combo I have the tendency to run it into the ground.

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Last edited by ronstory; 06-02-2014 at 01:11 PM. Reason: typos
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Old 06-07-2014, 04:07 PM
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Got good new and bad news back from the engine builder. Good news is that the block mag'd good and the sonic showed the min wall thickness at 105 even with .030 already bored. So I'm good to go for 0.040 over.

The bad news is that the rebuild was just about as crappy as it could be. Cheap 8 brow cast pistons, reused rods that weren't round, cam retainer was installed upside down so the oil passageway didn't like up and ruined the retainer. Oh, and the crank was scored and already 0.030 under.

So it looks like I need to buy new parts, so I'm now doing a 461/4.25 stoke engine.

Anybody have a good 461 kit they recommend? I'm looking to build about 380-400hp and 450-500 ftlbs of torq. I don't care much about above 5000 rpm (I have a different car than that). This is a cruiser and will likely never see a track, and I'd like to get 16 mpg on freeway.

I need to take apart the 6x-8 heads and see if they are in good shape, but I'm not very hopeful since the they were rebuilt by same "production engine builder" that did the block.

I was looking are KRE D-ports and for unported 85CC chambers in the 250-260cfm range. Tin Indian Performance seems to have the best prices for unported at $1900 a set. Has anyone orders a set from the Tin Indian? Any good?

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Old 06-07-2014, 05:33 PM
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Don't go to .040" over if .035" will clean up. We sometimes get in a habit of going to the next normal size over even though piston manufacturers have no problem with .005" increments. Never hurts to maintain as much wall thickness as you can.

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1967 original owner Tyro Blue/black top 4-speed HO GTO with all the original parts stored safely away -- 1965 2+2 survivor AC auto -- 1965 Catalina Safari Wagon in progress.
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Old 06-07-2014, 07:36 PM
ronstory ronstory is offline
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Good point, the builder was trying to figure out how deep the one rust spot was. I'll ping him again.

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  #18  
Old 06-20-2014, 12:33 AM
ronstory ronstory is offline
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OK, got word back form the builder that I need 0.040 over pistons. Even then there was the tinyest bit of residual discoloring after the honing. I never would have noticed it, but he is perfectionist.

Now i have another weird one on the 6X-8 heads. When I started pulling the valves, the inakes are 2.11 30 degs valves/seats... and the exhaust are 1.77 45 deg valve/seats. WTH? Since I'm trying to no add any head chamber volume, should I just get the seats cleaned up at current angle and then upgrade the valves to Ferrea 5000 series?

Do I need convert everything to back to 30 degs or convert the intakes to 45 degs?

This Pontiac stuff is weird. ;^)

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1964 Catalina ragtop
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Old 06-20-2014, 01:02 AM
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Actually Pontiac did 30° intake and 45° exhaust valves. Only a couple exceptions on Pontiac performance heads to the 30° intake. I usually go with the Ferrea 5000 valves for street engines.

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Mick Batson
1967 original owner Tyro Blue/black top 4-speed HO GTO with all the original parts stored safely away -- 1965 2+2 survivor AC auto -- 1965 Catalina Safari Wagon in progress.

Last edited by lust4speed; 06-20-2014 at 01:07 AM.
  #20  
Old 06-20-2014, 01:44 AM
ronstory ronstory is offline
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Oh drat.

I was reading the thread that 30 degs was good and 45 was chevy bad and I didn't realize it was only for the intake side.

So 30 deg intake valves are cool with 45 deg exhaust valves. Cool! ... and one less thing to fix.

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1964 Catalina ragtop
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