I run a Jones custom HR IR grind in my 383. It performs very well. I didn't know if the OP wanted to go this exotic... If you really want the best cam for your application talk to Mike.
Garth
Cams How do you choose one?
- Thread starter 1965barr
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I run a Jones custom HR IR grind in my 383. It performs very well. I didn't know if the OP wanted to go this exotic... If you really want the best cam for your application talk to Mike.
Garth
famous bob
mopar misfit
you could always match ur cam to ur convertor and gearing, rpm range , how u will drive it and where at !
nm9stheham
Well-Known Member
Mmm....manual 4 speed trans. No help in the TC department.
OP, you asked about milling depths. 2 things to consider: pushrod length and intake side milling of the heads. Reports here support that you can go .030" to .040' with a good chance of not having to change out pushrods; . It's just not a 100% guarantee; the parts stack up is on an individual valve/rocker/pushrod/lifter basis. The more you mill, the closer you move to having 1 or more pushrod length issues. Sometimes swapping around rockers can resolve this.
As you mill the deck surface of the head, you should mill the intake side of the head too, to maintain intake alignment. Mill .001" less off the intake side than the head side in the .030" to .040" range of milling. Deck-only milling has succeeded without intake-side milling for these amounts of deck milling, but it's less of a chance you are taking on a fit problem to do both.
Thinnest head gasket is .028" thick; Mr Gasket 1121G.
Let's mill and see where things end up:
.030": SCR moves from 7.8 to 8.2
.040": SCR moves from 7.8 to 8.35
DCR will move up in the same amount. A half point increase in DCR WILL show up in improved torque, throttle response, etc. So now with that smallest VooDoo cam, installed with 2-4 degrees added cam advance, the DCR is about .4 points higher than stock, both at sea level and at your elevation. It is not yet 'super snappy' but it is overall better and breathing has improved for the mid-upper RPM range to help the top end too. Maybe you can consider a one step larger cam too.
And, there is some more help if you set up and tune the ignition timing better. This can/should be done regardless of camming or milling or anything else. Other threads abound on that topic.
The piston changeout is a complete overhaul; that is a lot bigger bite to take. So not doing that is quite understandable. However, it would get things set up as best as possible. SCR moving up into the high 9's to 10-ish is the result. BIG difference in low-mid RPM torque and driveability! And perhaps the big thing: the cam possibilities open much wider, to include larger cams, and then the high RPM operation extends out too. Now you have more torque everywhere; it'll be more responsive whenever you hit the gas. That's the beauty for a driver, where there are situations where there is no 'optimum gear' available with your manual trans to avoid 'falling off of the torque curve' if the engine is set up around a too narrow RPM range.
skep419
No show, all go!
Basically research it to death. Buy one that doesn’t fit your needs. Complain about it’s bottom end power. Buy one that fits your combo. Vast in the glory that is low end torque.
1965barr
Well-Known Member
Motor has 500 miles on it when I got it my buddy had it in a lil red and wrapped it around a post , I got it to put in a 58 dodge big window truck I had but found a 58 392 hemi and used that instead so it has sat till last year and I pulled it apart and put new rebuild kit in it yes heads stock but valve job done, cam is stock 252 / 410 lift yes the dist was reworked I think 12 at idle comes in quick it is 34 or 35 . Tried to post a video but says to big will try later again. More reading and head scratching to make and thanks for all the help this is great ,might have to go to Manitoba lol
nm9stheham
Well-Known Member
Sounds like you know this game better than you admit LOL.
For the lower compression engines, guys are limiting ignition timing in the same mid 30's range but pushing the initial up around 20-ish. A method to limit the mechanical advance, to less than the 22-24* of the stock distributor, is needed, like a limiter plate from FBO.
How to limit mechanical advance in a mopar distributor, tuning for street, strip or all out racing, cure that rich stinky idle, win races
OK, on the valve job done; sounds like the heads are 'up to snuff' 'specially if the guides were renewed, so you won't be into that added cost this time around. Any consideration for just putting on newer heads, like the Edelbrock Performers or Indy-RHS? More expense by quite a bit, but you get a lot of bang for the buck for a slap-on upgrade. Chambers are right a 10 cc's smaller than stock, and head breathing is maybe 75-100 HP more, OOTB. Then if you are ever in the mood to upgrade the bottom end, the world opens up a lot wider for cam selection, etc.
Just for perspective for you: My son has an identical car to yours, and with the 10:1 SCR in a 340 block, moderately cammed for a DCR of 8.0, and the Performer heads, it has NO dead zone at the bottom end with a 2200 stall TC, and will spin some modestly wide tires at a bit over half throttle in 1st. (3.55 rear gear, Suregrip, like yours.) With the head breathing, it goes easily past 6000 RPM. (He really has not yet pushed it.) The first time I dove into a corner at speed in this thing, it was a bit of an unknown on how it would react, simply because it was a new car and engine combo. When I hit the gas right after corner entry, the lower stall TC locked up in an instant and the engine was coupled to the rear wheels and well 'up in the torque band'. With a tweak on the steering input, I could set the rear end out nicely and throttle steer it through the corner; this was in 2nd gear and around 50-60 mph when I hit the throttle. Veeery nice for an old A-body if you like road race/rally type of driving. (Being rally guys, we were ecstatic!)
You will need to post the video on You tube or the like and then post a link of it here.
1965barr
Well-Known Member
nm9stheham I don’t have a lot of experience with motors but done lots of reading lately and doing don’t know the secrets wish I would of paid more attention, I raced bikes,sleds when young ,then got into dirt oval racing 18 years Wissota and Imca modifies ,my cousin built the motors and I conscendtraded on building chassis and set up plus the fun part driving lol. I traded fab work or machining for engine work from friends to busy doing the other things never got to motor building but I say never to late to learn.Just wishing it was simple change a cam , but I’m learning I need to make more squeeze to make a happy motor RRR said his was at least 8:5 ,so learning different options how to do it, don’t mine spending money in the right places, but trying to learn the right place . As for road courses like them and raced on them , the 65 has .940 bars and rear springs plus 16 to 1 steering from firm feel hope it corners a little I’m with you about coming out of corner but mine were left lol
1965barr
Well-Known Member
Just wanted to add Thanks for Fabo and the members for showing and helping out on experiences and just coming forward with help this is priceless to me . I did a lot of reading and bookmarking to build my 65 from motor swap to 4 wheel discs . Thanks again for sharing gary
nm9stheham
Well-Known Member
Ah so you are the 'chassis guy'.... so you appreciate good handling and cornering. So you know that good 'grunt' (torque) at the wheels is part of the whole package. Looks like it with the suspension upgrades you have. (I see Bilstein's in your future, if you don't already have them LOL). I remember going through all the anti-squat design stuff that you undoubtedly know, and concluding that if you are turning both L & R on roads that go up and down, and braking as hard as accelerating, all that stuff works as much against you, as for you.
Yeah, RRR's example has some unknowns, in that we don't know the trans, or TC stall speed if an auto, and defining 'fun car' varies with us all and is subjective. If 'fun' for you is in a straight line and you have an auto, things change for the engine design. So that is why the application info is so important. If you want to corner hard on the street, then that makes me think the wide torque band approach is all that more important. (Though I don't know how curvy and undulating your local roads are.)
It may seem idiotic to have so much torque at the rear wheels that you spin the tires at half throttle in 1st, but when you get 2nd and or 3rd in a manual trans car, all that 'excess' torque at the wheels suddenly gets whacked by the change in trans gear ratios. So you gotta have gobs of excess torque in 1st to end up with adequate wheel torque in 2nd and 3rd, where you really need it to throttle steer through the higher speed corners.
You're all over the map for the RPM when you power through an unknown radius corner on the road or in a rally. You just can't 'rear gear' optimize it like on a circle track to work with a narrow torque band in the engine. It's either a lot of gears or a wide torque band in the engine.
Hope I have not digressed too much....
(Edit to add: Oh yeah, I am just getting into the snowmobile thing at age 65 LOL)
Yeah, RRR's example has some unknowns, in that we don't know the trans, or TC stall speed if an auto, and defining 'fun car' varies with us all and is subjective. If 'fun' for you is in a straight line and you have an auto, things change for the engine design. So that is why the application info is so important. If you want to corner hard on the street, then that makes me think the wide torque band approach is all that more important. (Though I don't know how curvy and undulating your local roads are.)
It may seem idiotic to have so much torque at the rear wheels that you spin the tires at half throttle in 1st, but when you get 2nd and or 3rd in a manual trans car, all that 'excess' torque at the wheels suddenly gets whacked by the change in trans gear ratios. So you gotta have gobs of excess torque in 1st to end up with adequate wheel torque in 2nd and 3rd, where you really need it to throttle steer through the higher speed corners.
You're all over the map for the RPM when you power through an unknown radius corner on the road or in a rally. You just can't 'rear gear' optimize it like on a circle track to work with a narrow torque band in the engine. It's either a lot of gears or a wide torque band in the engine.
Hope I have not digressed too much....
(Edit to add: Oh yeah, I am just getting into the snowmobile thing at age 65 LOL)
1965barr
Well-Known Member
Stock 360 running hope this worked , been tossing around the head idea for this motor , a friend actually has a set of indy heads lax 62cc,1.92 int. /1.625 ext. he took off for alum but he races the car. They are still stock that is good ,I have another 360 that will go alum heads if I want to go faster but that changes to much for what I want out of this car (exhaust) . Now with a head change what cam and not to get into det.territory?
1965barr
Well-Known Member
Nm9stheham you’ll have fun sledding ,just gave it up 6 years ago rode in the mountains here nothing like fresh power to ride in lol. Made the wife a promise one extreme hobby at a time I’m now into scuba diving.
Wyrmrider
Well-Known Member
Is that a closed chamber or open?
any idea how far your pistons are down the hole
62 cc and a .028 gasket- let nm do the math
It does not appear that you are going to have any quench with current pistons
and compression should be low enough so short quick cam can be used
let's see what nm says
any idea how far your pistons are down the hole
62 cc and a .028 gasket- let nm do the math
It does not appear that you are going to have any quench with current pistons
and compression should be low enough so short quick cam can be used
let's see what nm says
famous bob
mopar misfit
My bad, didn`t catch that---
4 SPEED, I D GO W/ THE RPM UR GOING TO BE DRIVING AT, GEARING WIL ALTER THAT THO.
Always better to go smaller than too big. Call a few cam companies , listen to their b.s. and make up ur own mind.
Do we know which "stock" cam the OP has?
here's the specs for the three I've been able to find-
360 2 barrel 71-74 Hydraulic 410/412 252/256
360 2bb 75-up Hydraulic 410/410 252/252
360 4 barrel Hydraulic 430/444 268/276
here's the specs for the three I've been able to find-
360 2 barrel 71-74 Hydraulic 410/412 252/256
360 2bb 75-up Hydraulic 410/410 252/252
360 4 barrel Hydraulic 430/444 268/276
You choose a camshaft the same way you choose a carburetor. The same rule applies. You will be happier with a smaller one than one that's too big. You can take a totally stock engine, put a good hot timing curve on it and headers and make it scream. It's all relative. Too much of one thing will start the snowball effect that requires you to change everything else in the domino effect.
1965barr
Well-Known Member
Hi cam is 252 410 lift, yes RCD bilstein shocks are on 4 corners, and heads are closed if they will work for me have to take them to get check but a good deal if I use them ,for the quench probably need flat tops ? Don’t know how far down they are. The only cam company I’ve heard from was Howard’s still waiting from jones nothing from anyone else.
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1965barr
Well-Known Member
Just playing with numbers with those heads and thin gasket I think Dcr is 7:74943 could be wrong cannot figure the rest out ,I only have an iPad to play with trying to find a program like Nm uses.
Wyrmrider
Well-Known Member
YY
you can't compare comp advertised duration with MOPAR they are measured in two very different ways
and the MOPAR stock cams tend to have really long closing ramps
just based on seat duration the stock 252 Mopar has more duration than a 256 Comp
but the comp is quicker- more intense
The Mopars tend to bleed off your Dynamic Compression
The long close ramp is to keep them quiet as seat recesion occurs- , and later used to dilute intake charge with exhaust gas for emissions-
In any case the Comp was designed for Small Bloc chevys and there are a lot better choices for a MOPAR
The 340 cam is even worse
The Comp is a 40 year old design- the stock Mopars 50 years old- much improvement in springs and cam design since then
you can't compare comp advertised duration with MOPAR they are measured in two very different ways
and the MOPAR stock cams tend to have really long closing ramps
just based on seat duration the stock 252 Mopar has more duration than a 256 Comp
but the comp is quicker- more intense
The Mopars tend to bleed off your Dynamic Compression
The long close ramp is to keep them quiet as seat recesion occurs- , and later used to dilute intake charge with exhaust gas for emissions-
In any case the Comp was designed for Small Bloc chevys and there are a lot better choices for a MOPAR
The 340 cam is even worse
The Comp is a 40 year old design- the stock Mopars 50 years old- much improvement in springs and cam design since then
...but now we know the current cam is ~410/256 and the OP want's "a little more fun" without a lot of other mods needing to be done.
People are suggesting .500 lift and .290 duration with a bunch of other mods necessary.
I'm simply suggesting a marginally more modern grand with a slight to moderate increase in lift.
Anyone else got a specific grind in that "one or two steps up" range?
People are suggesting .500 lift and .290 duration with a bunch of other mods necessary.
I'm simply suggesting a marginally more modern grand with a slight to moderate increase in lift.
Anyone else got a specific grind in that "one or two steps up" range?
nm9stheham
Well-Known Member
Just getting back to this..... another 50-55 hour work week on the road.....
I am getting lower numbers.... like DCR of 7.4 at sea level with the .028" thick head gaskets, and either Indy or Edelbrock Performer heads with closed chambers. DCR becomes 6.8 at your elevation; this is about .7 better than stock, which is about all you will do without going into the block and replacing pistons. (Or milling those small chambered heads even more..... which I would not do, with an eye to the future.) This is with the smallest VooDoo cam installed with 2 degrees added advance. You're nowhere near to detonation-land.... unless you muck up the ignition timing a lot! (I have had it happen in a race....detonated some forged pistons into meltdown with a DCR in the high 5's LOL!)
For your numerical work, be aware that the 360 pistons like that are about .100-.110" 'in the hole' (below deck), and have a dish of about 8-9 cc's that adds to the volume and reduces SCR and DCR.
Nice part is that you will get a LOT more top end breathing and extend the RPM range up, if you match it with intake and carb. Then you'll want headers....
Wyrmrider
Well-Known Member
cam
Mike Jones 256 Mopar special
253 or so Voodoo
same duration Howard with the (15) footnote in the online catalog
same duration Bullet from the .904 Mopar list
exhaust lobe will depend on heads exhaust port and exhaust manifold/ headers
so if you are looking at a shelf grind get one with a longer exhaust lobe if stock like exhaust ports and manifold
you have about a half dozen choices of shelf- else custom
Mike Jones 256 Mopar special
253 or so Voodoo
same duration Howard with the (15) footnote in the online catalog
same duration Bullet from the .904 Mopar list
exhaust lobe will depend on heads exhaust port and exhaust manifold/ headers
so if you are looking at a shelf grind get one with a longer exhaust lobe if stock like exhaust ports and manifold
you have about a half dozen choices of shelf- else custom
dibbons
Well-Known Member
For those who believe a picture is worth a thousand words:
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