Its been a little while.......

[Red63440]

Back in mid 1970 I bought a 66 2 door Plymouth Valiant with a 318 in it for $650.00. Shortly thereafter I went to a auto wrecking yard in West Elizabeth and bought the entire drive train out of a 68 Dart, 340 engine, A727 and the entire rear end including the springs, I think it cost me $300.00. The Valiant went up on jack stands and everything was removed from the engine to the rear end. The 340 was torn down, honed and rebuilt and balanced with new rings, bearings, Crane lifters, Mopar 284/484 cam, intake (LD340), Holley 780 dual feed carb with vacuum secondaries, Added a section to the original oil pan to make it deeper and lengthened the pick up, Hooker fender well headers and a set of 4:56.1 gears with posi brought up the rear. The transmission was rebuilt and a 3500 SS converter was installed along with a reverse valve body and Winters shifter. I had the car painted blue and gold and put ET slotted mags on it, the slicks were M&H 280 compound and were bought from Brougher's Speed Shop on Rt. 51 where I bought most of all of the parts I needed.

There was a counter man at Keystone Auto Parts and Machine Shop by the name of Frank Sprintz. He had lost his wife to cancer which left just him and his son and his son had started a band and wanted no part of Frank. I had lost my father to cancer and I guess we sort of saw each other as a fill in for what was missing so he helped me to build my engine, not in the sense that he "built" it but he gave me direction and I listened to Frank when he needed an ear. During that time he continued to do all he could to get is son involved with him and built the most beautiful Orange 426 Maxx Wedge 1964 Savoy I have ever seen, it was enough to show Franks son just how important he was to his father and they started racing every week.

I had a ball with that car and raced it at PID and Keystone Raceway for many years not to mention many quick runs on the 4 lane part of Rt. 48 between Mckeesport and White Oak.
I never lost a race in that car at either strip and have relived those races many times over the years, I also remember the day I sold it and watched it as it disappeared out of sight on its way to Ohio...not a good day.

So fast forward to today, new engines, different rules and most of my knowledge now and of the past 30 years pertain to the big blocks so I come to you for suggestions and the information it will take to build the last engine I shall build to power the car I always wanted but never had.
The engine is a 360 of a not so popular 1984 vintage, I don't have the engine here with me but do know that it has been professionally rebuilt and know that the engine will be torn down to verify parts such as cam, bore, head casting numbers, etc..I guess you could say I am looking for Frank again........Thanks for allowing me to share this with you....

 

[AJ/FormS]

In the mid 70s, I dropped a junkyard 340 into a 65 V100 wagon, With fenderwells,a complete 318 topend, and a used 318cam. It wasn't particularly fast , but it sure was a blast. I remember it fondly. I was about 23, and not particularly car-savvy. I remember the cheep pricing too.......compared to today.

The only thing I have to say about 360s is pressure. I have run up to a little over 190psi-gauge on 87E10,with aluminum heads. I don't know how much pressure it is possible to run on pumpgas, but I can say that even 175 is a blast on the street, with a 223 or 230 cam.
I know nothing about drag-racing except my car went 93 in the 1/8 at 3467#, with the little last-engine,street, 367.
I wish you every success.

 

[Red63440]

Thanks AJ, not looking to race again but as we both know its about everything working together to make a lasting combination. First builds are always a stress and a little guidance goes a long way which is why sites like FABO, FBBO and FCBO are so important to the future of the hobby.
With me not having all of the specs on the 360 that I have I am looking for build ideas based on a street use 360 with a little rumble, a little lope and a lot of fun.

 

[yellow rose]

Honestly, very little has changed. You can get different intakes (not always better), cams with more aggressive ramps (not always better) and better tires but mostly it's the same.

Straight is straight and round and round and balanced is balanced. Get the basics correct and you're pretty much assured of success.


BTW...the one thing that has gotten better in the last few decades is the valve job. There is zero reason to use the age worn 3 angle grind any more, unless you have flogged the head and that's what worked. I've never seen a head that wasn't better with something other than the standard 3 angle valve job.

 

[Red63440]

Based on what I have read about the new intakes the LD340 still holds it own some 45 years later. I am sure there are a lot of new grinds for cams, that’s one of the areas where I need help. I don’t want a racing engine but I do want a little giddy up when push comes to shove.

 

[AJ/FormS]

I tell you what, if you can afford it, get some aluminum heads and run the pressure up to at least 185, And with a free-flowing dual exhaust,
and ON THE STREET,with a 223/230 even 235 cam,
that 360 will hardly care what intake or carb is on it;
cuz the tires are gonna be smoking to 65mph probably even with a 2bbl, at least with tires that fit in the stock tubs,lol.
Some of the guys on here may not agree with this pressure philosophy; But my car ,IMO,should not have hit 93 in the eighth on the one and only successful run it ever made with no tuning whatsoever. It's just a 367 with a 230* cam, and 180 psi pulling 3467 pounds. And you can't run 180 with iron heads, on 87E10..... like mine does, and has, for over 100,000 miles.
So FWIW, there's that.
Oh and BTW, the 360 practically falls together at nearly 11/1 with KB-107s,or the KB-190s, so bonus!, it's a cheap build.
And if you zero deck it to run the FelPro .039, that gasket has no trouble at 10.9 on my engine, even to the extent of mine having been re-installed ,and,I Think mine are on the fourth go-round.

 

[Red63440]

About the only heads I could buy right now are the areohead units available on line and due to what I have read about them i'm not sure that would be a good choice. I hate to have to start buying parts for a fresh engine without waiting to find out just what parts went into making it up. I will be running 3:23.1 gears with an automatic and I know that an LD340 would work well with that combination and would prefer it over the air gap due to the cross over. I have my choice of either exhaust manifolds or headers...headers will give me about 10% or less so there are choices to make there too.
No, its not a small block nor is this the engine that we are talking about

 

[Red63440]

After doing some research I think I am going to do a cam shaft change and will go with the Comp Cams K20-223-3 along with an LD340 if I can find one reasonably priced. I prefer the LD340 due to the heat cross over for use here in the north east. A good set of Doug's or TTI coated headers, full dual exhaust, electronic ignition and a 750/800 cfm carb to round out out. Does anyone have any experience with this set up??

 

[Red63440]

Ok, I found that the engine is stock bore with new pistons, rings, bearings, cam shaft bearings, etc. It has the 1984 heads on it but all new valves including 2.02 intakes have been installed and I realize that the heads are the weak point of this engine but that can be changed in the future. I don't know what cam or springs were installed in the build so I have to come up with a cam kit that will work with what I have. The engine is going in a 68 Barracuda fastback with a A727 automatic and 3:23.1 sure grip rear end and I would greatly appreciate some feed back on cam selection.

 

[Wyrmrider]

Do you know what your real compression is with that late 360?
piston number and/or compression height- flat tops, eyebrows for the valves?
post up the cranking compression- oops too late
measure your deck clearance at all four end cylinders and see if they squared up the block
what springs, dampers? stock diameter or???
ani id on the cam?
If typical Low compression 360 a 270 class cam is way too big
Headers- try for 1 5/8 or 1 3/4 max for your street build- you need the velocity down low-- try pipemax Tri Y's would work OK
Think about a Magnum small dia starter
figure out the heads B4 even thinking of a cam
Stock 360's try a DIY port kit or at least clean up the bowls- if low compression think about 30 degree seats did they backcut the valves hard ex seats? bronze guides? new viton seals to be sure
alt 1 see if you can score some 308's but not enough improvement on what you have if your heads are in good shape- check the guides
you know the arguments about reworking 30 year old iron vs new EQ- your lowest cost new option
If you use open chamber heads and are changing pistons get the KB with the quench dome
closed chamber get the quench/ dish - get your compression wherever AJ recommends
if low compression I would not wish 268 chevy cam on my worst enemy. Intake closes at 60 degrees After Bottom Dead Center whereas a cam for low compression should close in the under 55 degree area max--AJ can explain the dynamic compression
let's not look at cams till you get them mechanical worked out
But as an example the Lunati Voodoo253/256 duration but still 454 lift intake closes 54.5 degrees ABDC- you could run 1.6 rockers if you wanted more lift but with stock heads not worth it
Comp has an intake lobe 254 duration but with .467 lift
Engle has one
Hughes 210@.050 cam has 512 lift their one size smaller 252 cam is 206 @.050 still has .475 lift
lots of other examples when we get to that point

 

[Red63440]

Do you know what your real compression is with that late 360?
piston number and/or compression height- flat tops, eyebrows for the valves?
post up the cranking compression- oops too late
measure your deck clearance at all four end cylinders and see if they squared up the block
what springs, dampers? stock diameter or???
ani id on the cam?
If typical Low compression 360 a 270 class cam is way too big
Headers- try for 1 5/8 or 1 3/4 max for your street build- you need the velocity down low-- try pipemax Tri Y's would work OK
Think about a Magnum small dia starter
figure out the heads B4 even thinking of a cam
Stock 360's try a DIY port kit or at least clean up the bowls- if low compression think about 30 degree seats did they backcut the valves hard ex seats? bronze guides? new viton seals to be sure
alt 1 see if you can score some 308's but not enough improvement on what you have if your heads are in good shape- check the guides
you know the arguments about reworking 30 year old iron vs new EQ- your lowest cost new option
If you use open chamber heads and are changing pistons get the KB with the quench dome
closed chamber get the quench/ dish - get your compression wherever AJ recommends
if low compression I would not wish 268 chevy cam on my worst enemy. Intake closes at 60 degrees After Bottom Dead Center whereas a cam for low compression should close in the under 55 degree area max--AJ can explain the dynamic compression
let's not look at cams till you get them mechanical worked out
But as an example the Lunati Voodoo253/256 duration but still 454 lift intake closes 54.5 degrees ABDC- you could run 1.6 rockers if you wanted more lift but with stock heads not worth it
Comp has an intake lobe 254 duration but with .467 lift
Engle has one
Hughes 210@.050 cam has 512 lift their one size smaller 252 cam is 206 @.050 still has .475 lift
lots of other examples when we get to that point

Just so you understand ...the engine is in Montana and I am in New York State..a buddy of mine is restoring the car and its an odd situation because I can't just reach out and do what I would like to do on it. Would Comp Cams K20-223-3 kit work in this situation or should I consider a smaller cam? I would think its close to factory compression for an 84, wish I could give you a figure. The engine is fresh, he pulled a head last night and I asked if the piston top was flat or dished and got no answer. I asked if there were markings on top of the pistons and he stated that the number 818 was on the top of each piston, again, no help.

 

[Wyrmrider]

can you have him measure the compression height of a piston?
low compression stock replacement pistons will die with a 268 comp cam
I'd like to see a true 10:1
what say ye AJ?
do you require an off the shelf cam?
is idle and vacuum important
what gas?
around town or mostly highway?
It's real easy to overcam a 360 which makes them no fun unless you are hotrodding
you want the most duration @200 you can get and the most lift where and past where the piston is moving fastest - 70 degrees to 90 degrees ATDC.
Chevy grinds have to open the intake early to get it up that far at the correct point, so they have more duration than is necessary which comes back around at the intake close point- although not optimum you can sorta get away with this with a high compression motor with gears and converter

 

[Red63440]

can you have him measure the compression height of a piston?
low compression stock replacement pistons will die with a 268 comp cam
I'd like to see a true 10:1
what say ye AJ?
do you require an off the shelf cam?
is idle and vacuum important
what gas?
around town or mostly highway?
It's real easy to overcam a 360 which makes them no fun unless you are hotrodding

Use will be cruising with a rush once in a while both town and highway, pump gas at whatever octane is needed, after market A/C will be installed with power disk brakes and I don't care where the cam comes from as long as it works. I have sent him an email asking for a measurement. Heads are fresh, new bronze guides, new valves including 2.02 intakes and new viton seals.

 

[Wyrmrider]

so far so good
which head number so we can figure ccs

 

[Red63440]

so far so good
which head number so we can figure ccs

The head casting number is 4343475A

 

[Wyrmrider]

this thread says 70-72 cc
Got some Heads, Which ones are best? - Mopar Forums
Those are the correct vintage heads for a 75-80 360 81-84 318 4bbl and 75-84 truck
they may have smog holes so plug them if not using AIR
came with 1.88 x 1.6 valves installing 2.02 valves has been done before- I hope they opened up the bowls and blended- viton seals so a premium job
basically all large port heads are the same
should have hard ex seats
from stan weiss site 202 intake valve stock heads
================================================100===200====300===400===500
Chrysler 915J Iron HPMM 156/73 2.02/1.60 N/A ---------------------------66/63 --123/110 170/135 206/145 220/148
hrysler 974 Cleaned and milled IQ52 11/32 SS Iron N/A 2.02/1.60 Pipe N/A 65/50- 132/103 184/131 207/143 210/146
Chrysler 974 Cleaned and milled IQ52 Iron N/A 1.88/1.60Pipe N/A---== ----- 58/50 115/92 173/132 202/143 208/145 3/8 stems 1.88 intakes
note how 2.02 helps low lift on unported heads
I frequently use 30 degree seatsfor the same reason
I take the 202 valves and cut the new 30 degree face then I have to reduce the dia slightly because the edge gets too thin then cut the seat out where the current top cut is and then narrow the 45 and so on= really helps the "curtain area" for .500 lift builds good velocity too
does motor have dished pistons?

 

[Red63440]

this thread says 70-72 cc
Got some Heads, Which ones are best? - Mopar Forums
Those are the correct vintage heads for a 75-80 360 81-84 318 4bbl and 75-84 truck
they may have smog holes so plug them if not using AIR
came with 1.88 x 1.6 valves installing 2.02 valves has been done before- I hope they opened up the bowls and blended- viton seals so a premium job
basically all large port heads are the same
should have hard ex seats
from stan weiss site 202 intake valve stock heads
================================================100===200====300===400===500
Chrysler 915J Iron HPMM 156/73 2.02/1.60 N/A ---------------------------66/63 --123/110 170/135 206/145 220/148
hrysler 974 Cleaned and milled IQ52 11/32 SS Iron N/A 2.02/1.60 Pipe N/A 65/50- 132/103 184/131 207/143 210/14
does motor have dished pistons?

They are dished......he said the pistons looked like a soup can upside down.

 

[Wyrmrider]

Ok we're dealing with a stock block low compression 360
Maybe AJ will chime in with some calculations
but I'd keep the cam in the 256 degree @.006 range with an Intake close point of less than 55 degrees After Bottom Dead Center (ABDC) @.006 tappet lift to get some dynamic compression
Mike Jones most likely has the best grind in this class 256@.006 with .305 lobe lift- big at .200 asymetrical profile It's his big block motorhome grind and wears really well Mike would pick the exhaust to match your build and exhaust system fill this out and point him at this thread for the flow numbers if using heads that match what I posted above Street Performance | Jones Cams he can nail your requirements or he'll advise

comp cams has nothing designed for MOPAR- they use their chevy design- thanks comp (you have to go to a 268 comp to get that much lift- it would die)
Howard has a couple example
HM2063164A . .475 .316 252@ 206 @.050 126@200 (verify that may be a BBM number)
Engle
K-52HYD 458" .305" 254° 209°
Lunati may have a Voodo for motor in this range
I saw a
VD 454/475 258/265 112 part number 10230701 (again I do not know if this is a BBM OR SBM number- you would have to ask
I think this cam is one size too big, you would have to ask if they have a shorter MOPAR grind
perhaps our Crower friend could chime in
Most grinders use one size fits all for MOPARS I like to support those that have given Chrysler some individual thought

now if you go to Higher compression pistons- the KB reverse deflector quench designs are best with those heads then everything changes

 

[Red63440]

Ok, sent a message to Jones Cams and the cam pn.10230701 is a BB cam..... would the old 484/284 Purple cam work on this set up or is the compression just to low?

 

[yellow rose]

I'd call Jim at Racer Brown. No sense in buying an off the shelf cam. In the time you've spent reading web opinions you could have ordered a cam already.

And I'd be STUNNED if jones ground you a cam for a .904 lobe for what you want. STUNNED. He wanted to sell me an .842 lobe because I looked it up. And my cam is considerably bigger than yours.

 

[Wyrmrider]

You would have to e-mail lunati and see if they have a .904 Mopar grind one size smaller than that 10230701 for the SBM (as with others they used to use "universal" for short voodoos but said all of them are now Mopar specific- but check
284 is a long way from 256 you would need low gears, loose converter and have a race only motor, no low end
jones only has a few .904 hyd lobes , more soild his 256 is a great one

 

[TripleL]

So with low compression the lower duration increases static compression,correct? I'm assuming you want the most lift you can get while staying within your advised duration

 

[66jim]

Today you have the advantage of the internet, back in the day if could be much
harder to get info of this type. There are is lots of experience on FABO but you
can easily get information overload, do your best sort out the highs and lows.

 

[Wyrmrider]

So with low compression the lower duration increases static compression,correct? I'm assuming you want the most lift you can get while staying within your advised duration

Dynamic compression not static
otherwise you are correct- more area under the curve not just more lift
your choice of duration is how it drives (along with the lca)
intake close point determines dynamic compression

 

[AJ/FormS]

So with low compression the lower duration increases static compression,correct? I'm assuming you want the most lift you can get while staying within your advised duration

Read Wyrmriders response carefully; it is correct.
Here; I'll expound;
So with low a static compression ratio, the earlier closing intake valve of a lower duration cam increases dynamic compression pressure,correct? Bold text added.
Simple answer yes.
But you don't ALWAYS have to sacrifice .050 duration to get that higher dynamic compression ratio. It really depends on the length of the ramps. As a fer instance; say you like a 223@.050 intake duration camshaft. The opening and closing ramps may jump this up by say; 38* to 58*, at advertised of from .008 to .006 tappet rise. This makes advertiseds of 281 down to 261. That is to say; all 223s, in a given engine, will make about the same absolute power at some higher rpm where they make peak power.. But obviously the 281 will idle like a race-car engine, while the 261 will be pretty smooth.
This also translates into how they will perform at low rpm, say below 3000 rpm; with the 261 making some 20psi more cylinder pressure, it will run circles around the 281 at these lesser rpms. But the 281 will not make any more power than the 261 cuz it still just a 223@.050. So getting greedy for intake duration, depending on the .050 and the combo, can make or break your smile-factor after installation.

But hold on we're not done yet. The engine cannot begin to build cylinder pressure until the intake valve is on the seat and not leaking. And at the advertised specs of .008 to .006 TAPPET LIFT, the intake valve, being on the other end of the rocker arm, is still OFF the seat from .009 to .012 !
And there is no way to know how much more duration it will require before it finally closes. The assumption is that the faster 261 cam is gonna close first....... but there is ZERO guarantee of that. That 223@.050 cam, therefore, may not close the valves until very very late in the cycle. This does not matter much to a race engine that might operate between 4000 and 6000. But at stall-rpm to 3000 it makes a really really big deal; and the lower the stall, the worse it gets.
This is why shopping for a cam is no small matter when the STATIC compression ratio is in the basement.
Hope that makes it clearer.......lol.
xxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxx
Just for something to think about the fun place to start at is 130/135VP.
It doesn't much matter the engine size or the cam size or the pressure, none of that matters; all engines with similar VPs will run at about the same performance level from stall to 3000,in a given combo, depending mostly on the TC stall.
By 140/145 you are having fun, and the bigger the rear gear, the more fun you will be having. With iron heads it will take more cubic inches to get much more than 145VP (read about VP by clicking on the blue link at the bottom of this page.) But 145VP is easy with a zero-deck(or close to it) 360 and closed-chamber aluminum heads.
The smaller the engine, the harder it is to make bigger VP numbers. So the work-around is to just get a hi-stall TC and not operate in that sub 3000 zone. That means you can still have fun with a smaller engine; you are just gonna need more stall and more TM. I'm just a fan of more cylinder pressure for the way it wakes up the engine at lower rpms.Also, to my way of thinking, if you have to buy a TC and gears, sometimes it is just cheaper to buy pistons and fix the low Static compression ratio, in the first place; it has a bigger pay-off.

But some of this philosophy does not work on a manual trans car with streetable gears, which operates in that low-rpm zone almost full-time. For example 2800rpm with 3.23s is about 23.5 mph in first gear. So that combo is stuck with the engine married to the rear tires every single time it is accelerating from zero mph and it ain't getting any better until after 30 mph. Then, when the operator shifts into second at say 2800, like I do,the Rs fall back to 2000, and there I am stuck in la-la land again. And it happens on every shift. So I said to heck with that, and went straight to Aluminum heads which allow up to(and beyond) 185 psi, which jumps the VP up to 160 or more, depending on the cam's Ica. Now when the rpm falls to 2000, there is plenty of VP to accelerate with.... normally, lol.
Ohchit, I bet I muddied the waters right there, lol.

Here is a calculator for you to play with. Enter your engine specs, then play with the Static compression ratio, and then with the Ica, and see how big you can make the VP to be. To make working it faster, click on "page back" in the upper left corner, and you won't have to keep re-entering all the engine data.Enter your operating elevation to be accurate; this also makes a really big deal.
For iron open-chamber heads, do not exceed 160psi, as for a newbe, that is pushing the limits for detonation resistance for best gas. With aluminum heads you can target 185psi, but it would be nearly impossible to achieve that in an actual build, with a 318, for a reasonable amount of money.
As to the Ica, stop at 68*. For a 318 streeter this is just asking for trouble. Likewise the stock 318LA cam has an Ica of about 50* so no point in going any smaller than that.
Just remember these things;
1) as for acceleration;low VP numbers can be circumvented with higher stall TCs. By 3000 stall, even 2800 with some combos, Big VP numbers are no longer important.
2) However, the usually associated higher cylinder pressures always produce a stronger midrange, and more power. And
3) cruising with low VP numbers definitely reduces your cruise fuel economy.


At 652cc the 318 is severely handicapped. By contrast the stock 360 is around 737cc. and a 408 is ~832. So what this means is the same total chamber volume on each of these, will quickly drive the STATIC compression ratio to the moon. The commonly available parts just happily work well on a 360+.020; like this ;
(744.6+78)/78=10.55Scr The same 78cc on a 318 looks like
(652+78)/78=9.36Scr. and on a 408 it is
(832+78)/78= 11.67Scr
10.55 on the 360 just happens to be about perfect for aluminum heads and a small street cam; read early closing intake, of about 58 to 62 degrees advertised. 9.36 is already limiting the 318 to iron heads and a small cam...... just like the 318 Magnum runs.
Strokers usually run dished pistons to reduce the pressure
TripleL,Happy HotRodding