Opinions on low end 360?

-
HP2

HP2

Well-Known Member
Joined
Nov 19, 2014
Messages
103
Reaction score
29
Location
Various places
Planning to do some upgrades on my 70 `cuda vert, I will keep the 904 tranny with the 2,200 rpm converter and will stay with the 3.23 SG. Brand new tti 3" H-pipe exhaust is already installed, did that before I made decisions about the power plant.

I don't know very much about the 360 yet. It takes no oil, has good compression and runs strong. Power comes in strong at around 3,500 rpm's and then it wants to rev to the moon. A little screamer. Recent owner said it was a "crate engine", but he couldn't confirm it. I have found out that block is casted 1971. It is externally balanced.

I want an engine working with the converter and 3.23 ratio.
I'm looking for a power band suited for the rpm range the engine will be driven in. Rarely over 4,000 and mostly between 1-3,000.
Plain and simple responsive and economic motor.
You might think I'm odd wanting to build such a boring engine, but I have had many cars with hot engines making lots of power, and as we all know high revving engines like that requires high stall converters, high flowing induction and exhaust, steep gears and so on. Honestly, most of the time they are not very fun though. Not very reliable either. But thirsty. I still have my Charger if my mood turns to racing mode
laugh.gif


I think this 360 still could be able to smoke the 275's. Do you?

Hopefully I will be able to use the same crank, rods, pistons and heads. Of course more cubic would take it longer, but I'm on a budget.
I'm thinking a good aluminum dual plane with long runners like Edelbrock RPM or Weiand Action Plus and a Thermoquad on top. Long runners are good for low end!
Camshaft selection will of course be very critical and here I need advice. A good bunch of lift, steep lobes but not much duration? Any opinions?
I will ditch the headers since they are crap. Maybe I could go with cast iron manifolds since I don't need a lot of flow?
If my heads needs work it might be a better idea to find something else. If I stay with iron I will aim for 9.5:1, if I can afford aluminum then 10.5:1
Will also have to get a distributor with vacuum advance.

Let me hear what you think folks!
 
You've got a Great Idea
With the short powerband, you can take advantage of the trans gear ratios. This means you can tighten up the LDA and build some cylinder pressure very early on in the rpms. And you won't need much compression ratio to do it.You say;"Camshaft selection will of course be very critical and here I need advice. A good bunch of lift, steep lobes but not much duration?" I say;You are on the right track.
All your ideas are pretty good, except I would go with long-tube headers, the longest I could find.But it won't be critical, cuz you will have a whole bunch of torque as it is.And with a short-period/low-overlap cam, the inertial tuning of the individual tubes may not be very effective.But if you are able to get into the 210*and up, cams, then for sure headers will be working.
I would measure the exact Scr of that engine.That way you can adjust the Dynamic CR, by ICA , for your local fuel. I do this by pouring heavy-oil into the cylinder with the piston at exactly TDC, and to the bottom of the plug hole, which must be at the very top of the chamber. This can only be done with the engine out of the car.You need to know the exact volume of oil that went into the chamber and the exact size of the bore. Then a little math spits out a number.Knowing this number, gives you an excellent chance at success when picking a cam;to get the right one the first time.
I,of course, would strive for a tight-Quench design. Since most/all of your driving will be at such low rpm, the tight-quench will/may allow your engine to run more timing without detonation, making it more efficient, and getting the best mpgs it can.Without tight quench, it may be difficult, but not impossible, to set up a good timing curve.
Since you are not overly concerned with max power, you can build to a lower Static compression ratio. Meaning open chambers are on the table.
It will be tire-fryer for sure.275s will not tame it.She will need a traction-aider.


I did a quick Wallace calculation; With a 4.03 bore and a Scr of 9.50, you can run a 56*ICA to get an 8.0DCr.This 56*ICA falls into the zone of many popular off-the-shelf cams, such as a 262*. However, for you, if it were me, I would go custom.I would ask for more lift and faster ramps. Your heads may need special springing, and possibly a rev-limiter. But the extra lift would,IMO,be worth it. For me,it would be that or some custom porting to get the heads to do the work instead of the cam.
To get 9.5 with a 4.03 bore(748.3cc swept) requires a TOTAL chamber volume of 88cc.This will require open-chamber heads , the .039Fellpros, and either custom pistons to get tight quench, or the pistons will need to be down in the hole some,(around .034). With closed chamber heads,custom or dished pistons will be needed.So that takes us back to the fluid-fill method, to quickly see where you are at without disassembly.
 
You are on the right track, IMO. The 2200 stall converter makes a 1000 RPM torque engine questionable.... so maybe look to 1200-1500 RPM as the low end for cam selection. Good CR is needed but you will have to match that with the pistons and cam to keep the DCR low enough. I am assuming you have open chamber heads will make quench pretty much impossible so that means you need to not go too high on SCR and DCR. Going with aftermarket closed chamber heads like Edelbrock RPM Performers or Indy RHS types will make quench easy to achieve and you can go with higher SCR/DCR. IMO, either of those is a good investment if you can afford them, and you don't need any of the high flow options for those heads with your proposed build. The AL heads have the advantage of lower weight and being able to push SCR and DCR a bit higher.

I would consider 1.6 ratio rockers for more lift with limited duration. This is an added cost of many hundreds of $$ however.
 
I don't quite understand, does it have a 4 bbl on it now? its most likely not a crate Mopar engine with that date block. If indeed it has good compression numbers and doesn't leak or burn oil why go spend all the money on a rebuild and new heads when your not going over 4,000rpm and going to leave the stock converter and 3.23 gear in it, plus ditch the headers for logs? I would simply pull the cam if you think its to big, get one that is near stock to the 340, or better yet get the lunati with 220/226 @.050 475/495 lift or even the next smaller one, since you have the TTI exhaust keep or get new headers they make more HP and torque even down low. If it doesn't have a 4 bbl find a used t quad and performer intake and go with that, no need for a LD340 or performer RPM intake when your looking for under 4K performance. Also the fast ramp cam probably wont ad a lot in performance for the amount of added wear and noise you may encounter. JMHO.
 
EL5DEMON340 said:
I don't quite understand, does it have a 4 bbl on it now? its most likely not a crate Mopar engine with that date block. If indeed it has good compression numbers and doesn't leak or burn oil why go spend all the money on a rebuild and new heads when your not going over 4,000rpm and going to leave the stock converter and 3.23 gear in it, plus ditch the headers for logs? I would simply pull the cam if you think its to big, get one that is near stock to the 340, or better yet get the lunati with 220/226 @.050 475/495 lift or even the next smaller one, since you have the TTI exhaust keep or get new headers they make more HP and torque even down low. If it doesn't have a 4 bbl find a used t quad and performer intake and go with that, no need for a LD340 or performer RPM intake when your looking for under 4K performance. Also the fast ramp cam probably wont ad a lot in performance for the amount of added wear and noise you may encounter. JMHO.
Click to expand...

Sounds good to me, basically a stock HP 360. 340 exhaust manifolds, 71 340 intake manifold, and a good TQ with a 340, or similar 268 duration, cam.
 
AJ/FormS said:
You've got a Great Idea
With the short powerband, you can take advantage of the trans gear ratios. This means you can tighten up the LDA and build some cylinder pressure very early on in the rpms. And you won't need much compression ratio to do it.You say;"Camshaft selection will of course be very critical and here I need advice. A good bunch of lift, steep lobes but not much duration?" I say;You are on the right track.
All your ideas are pretty good, except I would go with long-tube headers, the longest I could find.But it won't be critical, cuz you will have a whole bunch of torque as it is.And with a short-period/low-overlap cam, the inertial tuning of the individual tubes may not be very effective.But if you are able to get into the 210*and up, cams, then for sure headers will be working.
I would measure the exact Scr of that engine.That way you can adjust the Dynamic CR, by ICA , for your local fuel. I do this by pouring heavy-oil into the cylinder with the piston at exactly TDC, and to the bottom of the plug hole, which must be at the very top of the chamber. This can only be done with the engine out of the car.You need to know the exact volume of oil that went into the chamber and the exact size of the bore. Then a little math spits out a number.Knowing this number, gives you an excellent chance at success when picking a cam;to get the right one the first time.
I,of course, would strive for a tight-Quench design. Since most/all of your driving will be at such low rpm, the tight-quench will/may allow your engine to run more timing without detonation, making it more efficient, and getting the best mpgs it can.Without tight quench, it may be difficult, but not impossible, to set up a good timing curve.
Since you are not overly concerned with max power, you can build to a lower Static compression ratio. Meaning open chambers are on the table.
It will be tire-fryer for sure.275s will not tame it.She will need a traction-aider.


I did a quick Wallace calculation; With a 4.03 bore and a Scr of 9.50, you can run a 56*ICA to get an 8.0DCr.This 56*ICA falls into the zone of many popular off-the-shelf cams, such as a 262*. However, for you, if it were me, I would go custom.I would ask for more lift and faster ramps. Your heads may need special springing, and possibly a rev-limiter. But the extra lift would,IMO,be worth it. For me,it would be that or some custom porting to get the heads to do the work instead of the cam.
To get 9.5 with a 4.03 bore(748.3cc swept) requires a TOTAL chamber volume of 88cc.This will require open-chamber heads , the .039Fellpros, and either custom pistons to get tight quench, or the pistons will need to be down in the hole some,(around .034). With closed chamber heads,custom or dished pistons will be needed.So that takes us back to the fluid-fill method, to quickly see where you are at without disassembly.
Click to expand...

Finally! You are the first person who really listen and understand what I'm looking for :finga:
I had plans to build a long ram induction 440" first. People thought I was crazy.
Everyone is looking at what they use at the drag strip since the cars there make a lot of power. That's true, but they are built for that purpose, not for town-street-highway. People build street engines and takes them to the dyno and are often impressed by the numbers. Well, the dyno starts at 3,000 rpm. Does their speedos start at 55mph? I don't say they are wrong. They might street race their cars, but I don't use my ragtop to win street races. I like to smoke the tires but I also like to drive sideways and byways long distances with my wife, and for that I need good throttle response from idle and a well tuned engine for the rpm range I use it in. Horsepower numbers are not much worth if you don't reach the rpm's where they are produced.
I soon realized the intake and carbs wouldn't fit in an e-body so now my goal is to make this happen with the sound 360 that's already in the car. We'll see O:)

Thanks for your input about cam selection. I will measure CR, either by your method with thick oil, or by taking the heads off. I haven't decided what way to go yet. I'm working on my race car so if I have to take the engine out I'll have to get the race car done first due to lack of space. Anyway, I will do all the measurements carefully and properly so I know what I have before I go head shopping. I can get a pair of aluminum closed chamber 58cc but that will really bump the CR way high. http://www.anabint.se/Produkter_Bildelar_toppar_&_tilbehor___Toppar_SBM.html
I'm waiting for manufacturers flow numbers.
Maybe they could work if the slugs are below deck and/or a thick copper gasket?

The headers I have are shot. They are smashed and flat from running low. I thought a pair of original ex manifolds would be good because they fit and they wont leak. I don't have good experience from SB headers but I'm open for anything. I will make an order from Summit and they probably sell something that works.

A custom grinded cam is what I was thinking of. Are Comp the best?
 
If you want power down low put a mild big block in it and be done !
 
Years ago we built a low end bow tie engine for a shop truck. It was a 350 with 305 small runner heads. I can't recall the cam specs but it was probably about a 445 lift. We used the early model large 2bbl intake with an adaptor and a 350 Holley 2bbl. Had great port velocity and would pull stumps to about 4500.
 
HP2
As to cam selection, I think you might be jumping ahead too soon.
To calculate the Scr you need to know the exact chamber volume. There is no more accurate way than the cylinder fill-volume.The oil goes into every crack,crevice,and pit. A thick single grade oil (I used #30),has enough surface tension to not find it's way past the ring gaps.If the engine is on the floor it's pretty easy to do. On the stand,you need to be real careful to make the plug-hole the highest spot.You can use any cylinder; just be sure it's at TDC compression.
Because you are shooting for 9.5 Scr, choosing a cam will be a bit of a balancing act. Between; a short period/ hi-torque/low-rpm cam making perhaps too high a Dcr, and a slightly longer period cam, to reduce the Dcr to regular 87 gas, which might make a little less torque, and move the rpm of peak torque up several hundred Rs. So, really, IMO you might be getting ahead of yourself.
So,let's wait until the Scr is figured and try to work with it. Two thoughts come to mind; 1) it's a 360, and 2) 360s are almost IMO,the perfect A-body street engines.
This engine can be built and tuned to perform a multitude of different jobs. It's really hard to build an underpowered A-body street-360.It's easy to build a tyre-fryer 360.
I have one tidbit for you;I once put an entire teener top-end onto a 340.With fenderwell headers and a 2bbl, that thing was an awesome street brawler. The 318 cam was done early, but the 340 cam pulled real hard. It's so long ago now (1976), I can't say which I liked better. I stuffed it into a 65 Valiant wagon. I liked the teener cam cuz I could idle the engine down to 500 or less, and nobody woulda guessed it was much more than a 273.(At 450/500rpm a V8 almost sounds like a slanty.) That is until ,well you know, Kabam!
Now imagine adding 20 more cubes and most of it is in the stroke. In fact, a 360 is practically a stroked 340.
I have to agree with you on streeters with sbms chasing horsepower numbers. Your thinking is much like mine.I call gears and hi-stalls band-aids.They are needed when the engine just can't pull strong enough on the bottom. For a streeter, getting off the line is a big deal, cuz it will have to do that thousands of times in it's lifetime.I would estimate somewhere between 60,000, and 100,000 times.And more.
If you have been following my posts at all, you might know that my engine has had three different cams since I built it. From the 292/508/108 Purple(which I measured at 240) to a 223/230/110, to a 230/237/110 cam. In terms of street friendly tyre-frying, the 223 was my favorite.It made a very significant larger amount of sub-4000 torque, than the purple. I never missed the purple.The purple made it's power after 5000. Actually I would say it made it's peak close to 6000. It worked pretty good with 4.30s and 4.88s.
The 223cam pulled 3.55s easy. Smoked the 275s. It pulled a 2.02 O/D at 60mph. It would break 275s loose, anywhere in second gear at up to about 50mph. Just hammer down and hear 'em howl.This was with the A-833, the AG, and a 750DP, and at about 3800pounds. Now that's 360 torque.
Now I realize that Our engines are not quite the same;(mine has aluminum heads, 1.6 rockers, and a 10.7Scr ). But with iron heads,and a short cam, it can be tuned for a very strong lower-end. Perhaps even stronger than mine. Probably,even stronger.
So that's enough bs for now.
Don't worry;be happy.
All opinions expressed, are mine and mine alone, and not necessarily those of the masses.Where facts are stated they cannot be argued with, cuz, well, they are facts.
 
Listen to A/J he knows cams.
I actually am de-tuning a 360 to put in my farm truck, simple cam change gives it 300 ft/lbs at idle and 400 ft lbs at 2000 rpm, should make a good puller.
The 360 does have aftermarket pistons and aluminum heads, but I think it will pull good to 4500 rpm.
 
Well if you can pull 400@2000, you know a thing or two yourself.

And While I have experience with street cams up to the 292/508 in SBMs, I confess, This is a very small window of knowledge. So thanks for the support, but there are lots of knowledgeable fellows here, yourself included.

And 300 at idle. Well that will pull some chit!
 
AJ/FormS said:
Well if you can pull 400@2000, you know a thing or two yourself.

And While I have experience with street cams up to the 292/508 in SBMs, I confess, This is a very small window of knowledge. So thanks for the support, but there are lots of knowledgeable fellows here, yourself included.

And 300 at idle. Well that will pull some chit!
Click to expand...

Thanks, the gas motor will act almost like a diesel, but rev a little higher, but I never spin the old girl over 3500 rpm.
I only use it to pull with or haul lumber.

So to the op build the motor as you intend to use it, you will be much more satisfied.
A smaller cam is more forgiving than one that is too large.
 
jimmer said:
If you want power down low put a mild big block in it and be done !
Click to expand...

Ya but he's the newbee genius that likes to give the finger, he has a race car also !!! I'm impressed. What are you wanting to do that's so groundbreaking on this 360 again?? Oh ya a hi lift short duration cam and a eddy rpm intake.:finga:
 
sireland67 said:
Thanks, the gas motor will act almost like a diesel, but rev a little higher, but I never spin the old girl over 3500 rpm.
I only use it to pull with or haul lumber.

So to the op build the motor as you intend to use it, you will be much more satisfied.
A smaller cam is more forgiving than one that is too large.
Click to expand...

Sounds very much what I'm looking for!
What parts did you use? Carb, intake, cam, exhaust manifolds? Compression ratio?

I wrote Performer RPM in my first post but was thinking Performer. There's a RPM on my engine now. Sorry for the mix up.
Could the old SP2P be an option, or is LD4B better? Very difficult to find information about low end torque since everybody is looking for maximum power.
 
Now I need your op on intakes and more.
I have scored three different TQ's, two untouched in good condition and one that I supposed to be gone through and modified for a hot Chevy 327 but never used. Both dusty and dirty from sitting on a shelf in a garage for years. I hope I can put at least one good together.
What would the best intake be for idle to, lets say, 3,500 rpm?

I will have a custom cam made with steep lobes, pretty high lift, short duration and an intake that closes early to build pressure. I'm interested in your op in this area as well.

As said before I will adjust static compression by milling heads or/and head gaskets choice so I get as high dynamic compression as I think it can handle with the cam.

I now have the numbers on the heads, they are 3418915 so they can be the originals to this engine (1971 360") if I understand correctly. Then the valves are 1.88/1.60 which should be good for a torque build.

Since the engine will produce all its power down low some bad flowing cast exhaust manifolds even could help the engine by building back pressure? Teach me!
 
Forget about back pressure.
Inhale deeply, exhale through a straw. Now do 20 jumping jacks, and repeat. Continue until you die. Works same on engine. Forget back pressure.

TQ is a great carb, but not exactly for your stated goals. The small primaries will work wonderfully for/with a small short-period cam, but the secondaries are way overkill. I must confess tho. that I have made them run pretty good on stock-cammed teeners.
If you wanna roast the hides tho, a mechanical secondary carb is the way to go. But if you are gonna put skinnies back there, than a 2bbl will roast those.

I went back and reread your posts. The more I think about it, the more I'm inclined to think, that a more or less stock early 360-4bbl, with simple bolt-ons, will do.With that 2200TC, it will snap to attention, and even if it doesn't boil the hides, it will motor away pretty good.Almost any dualplane will work, including the oem iron TQ piece.

So on the cheap;If I read you right; your longblock, with an off-the-shelf 218ish cam,the TQ top, and headers, will do it. If it doesn't motor away briskly enough,3.55s will do it. The compression may have to be adjusted to keep the Dcr within your fuel limits.
And that takes us back to measuring your exact Scr.........On the cheap,you have to know this, cause adjusting the Scr gets expensive real quick!!
So measure it already....it's been 2 weeks since your 1st post.Chop-chop.
 
I own a '73-4spd 360 Cuda.

Less back pressure the better. This does not mean 5 inch exhaust. 2-1/2 max would be best in order to keep the exhaust gas moving along and not tumbling in the pipe. Headers would be better but it is not a mandatory item. To this end, I'd recommend the TTI headers for figment and overall performance over the 1 size fits all or the Hooker Super Comp headers for the E body.

The stock 360 heads are a 1.88-1.60. For a mello build, there fine. 2.02's would be nice (and a bowl porting with the cam I recommend below. Though it is not needed, at least have the bowl opened up to match the new valve size.) With iron heads, limit your compression to 9.0-1. The best intake for idle to 5500 RPM is in no particular order, stock TQ, earlier the better IMO, Edelbrock Performer, Weiand Action Plus.
Personally I'd use a cheap factory TQ intake. Budget reasons as stated earlier. Though a nice Edelbrock Performer or Weiand Action Plus will about equal or better the OE intake.

Leave the SP2P and the DB4 I think you said it was, on the shelf. The SP2P is a mileage master, does nothing for power. An RPM would also be fine for use. But they do not readily accept a TQ.

Cam.

Considering 3.23's are on the back and your tire is sky scrapper tall, I would not go beyond a [email protected] duration on the cam and lift no more than .500 unless you start doing head work. Which maybe the case for aftermarket springs that you should purchase with and to match the cam of course.

I'm a little iffy on a cam recommendation. You want more performance but your cruise rpm is very low. And your converter is a little high. To this end, I'll recommend a Lunati cam.
The 60402 (new part # 10200702)
1400-5800 rpm, .475/.494 lift, 220/226 duration @.050
112/108
You can advanced this cam for a little more down low power.
(This cam should cruise right in it's power band. So when you mash the go pedal, it should GO!)
If you use a 1.6 rocker, the intake goes to .506, exhaust goes to .527 (.52693)
IMO, 1.6 roller rockers would be nice to use. Hughes engines or Comp Cams has them & are recommended.
 
OH! Also! On tire size, I did say they were tall. Is a 235/60/15 good for you? That's what I would use. (Or a 245/60/15)

AAAAAAAAnd I'll disagree with AJ on the TQ carb usage. ;)

Tighten up the secondary spring for a delay in activation.
IMO, the TQ is the best on the cheap carb and a stand out In performance for a street and mild street/strip car.
I think it will fit the goals well.
 
AJ/FormS said:
Forget about back pressure.
Inhale deeply, exhale through a straw. Now do 20 jumping jacks, and repeat. Continue until you die. Works same on engine. Forget back pressure.

TQ is a great carb, but not exactly for your stated goals. The small primaries will work wonderfully for/with a small short-period cam, but the secondaries are way overkill. I must confess tho. that I have made them run pretty good on stock-cammed teeners.

If you wanna roast the hides tho, a mechanical secondary carb is the way to go. But if you are gonna put skinnies back there, than a 2bbl will roast those.
Click to expand...

Ok, I'll try to find a pair of better manifolds than the truck irons that I have.

I agree the TQ secondaries are too big, but what better option do I have? I don't want to use a Holley double pumper for this application - good for idle and WOT but not for cruising, and I don't like Eddies - we don't like each other. There's probably a 2bbl out there that would do a great job, but I don't know what to look for, and if I find it I'll be limited when it comes to intakes.
 
rumblefish360 said:
OH! Also! On tire size, I did say they were tall. Is a 235/60/15 good for you? That's what I would use. (Or a 245/60/15)

AAAAAAAAnd I'll disagree with AJ on the TQ carb usage. ;)

Tighten up the secondary spring for a delay in activation.
IMO, the TQ is the best on the cheap carb and a stand out In performance for a street and mild street/strip car.
I think it will fit the goals well.
Click to expand...

I already have BFG T/A's 275/60-15 in the back. Tight, but it works :)
 
I said I have made TQs work on teeners,Right? It's all about tuning. And I have Tuned a 600(list 1850) to get 32mpgUS, so Holleys can be made to work. Again, it's in the tune.The TQ has no aftermarket support, so tuning it can be a challenge. But since your build is so mild, it may work with minor adjustments. And like I've always maintained; I LOVE TQs.

The problem I forsee with a Small TQ on your build, is transitioning.
When you floor it at the bottom of first gear, your TC will flash to it's stall. Then the car will accelerate in first gear to 3500/35mph and the secondaries may have just begun to open. But you are shutting down. So the secondaries slam shut, leaving a huge puddle of gas sitting in the manifold. As soon as you again open the primaries, guess what, that fuel starts moving. And your plugs are not gonna like that. If you get tirespin, it will be less of an issue, but as you feather the pedal out, and the tires hook, the secondaries will again close, allbeit dryer this time.
No, for you I see a very small mechanical secondary 4bbl as a nice option. You will get all 4 bbls whenever you hammer it. You will be able to control wheelspin with the footfeeder, and feather it out as you approach your target mph or rpm.On the flipside, with no tirespin, you won't have fuel puddling under the secondaries from them suddenly slamming shut, so, getting back on it in mid-stride will be smooth and uneventful.
You can tune the TQ to minimize that puddling thing, or you can modify your driving style to work with those secondaries. Neither of which I would want to do. Furthermore, that vacuum sec carb will not let the engine unleash all its potential, at city cruising speed.
Say you are tooling along at 30 mph. with 3.23s and 28s in third this would be about 1200rpm,plus TC slip. But you wanna G-O, so you hit it! Tranny shifts down to second, and rpm climbs to 1700 plus slip/stall,say2200 . Well the secondaries might as well not be there,cuz they are not coming on line til around 50 mph. So what do you do? Slam it into manual low. So now the Rs climb to 2850 plus slip, say 3200. Ok now the secondaries are beginning to open. In just a little while they will smoothly come on line, as the vehicle smoothly accelerates;no drama.
I like drama. Capital D,Drama. I want tirespin, smoke,screaming pipes,and hard charging look-at-me-go. Especially with passengers on board. Like why do you think I spent a years wages on this beast, for smooth acceleration? Heck-no!
So for me it's a DP hands down. For you, if they make em in a 500, that would be big enough.And nicely controllable, and light 'em up at 30mph big fun, with giggles and smiles for everyone.
Ok enough bs already.
 
rumblefish360 said:
I own a '73-4spd 360 Cuda.

Less back pressure the better. This does not mean 5 inch exhaust. 2-1/2 max would be best in order to keep the exhaust gas moving along and not tumbling in the pipe. Headers would be better but it is not a mandatory item. To this end, I'd recommend the TTI headers for figment and overall performance over the 1 size fits all or the Hooker Super Comp headers for the E body.

The stock 360 heads are a 1.88-1.60. For a mello build, there fine. 2.02's would be nice (and a bowl porting with the cam I recommend below. Though it is not needed, at least have the bowl opened up to match the new valve size.) With iron heads, limit your compression to 9.0-1. The best intake for idle to 5500 RPM is in no particular order, stock TQ, earlier the better IMO, Edelbrock Performer, Weiand Action Plus.
Personally I'd use a cheap factory TQ intake. Budget reasons as stated earlier. Though a nice Edelbrock Performer or Weiand Action Plus will about equal or better the OE intake.

Leave the SP2P and the DB4 I think you said it was, on the shelf. The SP2P is a mileage master, does nothing for power. An RPM would also be fine for use. But they do not readily accept a TQ.

Cam.

Considering 3.23's are on the back and your tire is sky scrapper tall, I would not go beyond a [email protected] duration on the cam and lift no more than .500 unless you start doing head work. Which maybe the case for aftermarket springs that you should purchase with and to match the cam of course.

I'm a little iffy on a cam recommendation. You want more performance but your cruise rpm is very low. And your converter is a little high. To this end, I'll recommend a Lunati cam.
The 60402 (new part # 10200702)
1400-5800 rpm, .475/.494 lift, 220/226 duration @.050
112/108
You can advanced this cam for a little more down low power.
(This cam should cruise right in it's power band. So when you mash the go pedal, it should GO!)
If you use a 1.6 rocker, the intake goes to .506, exhaust goes to .527 (.52693)
IMO, 1.6 roller rockers would be nice to use. Hughes engines or Comp Cams has them & are recommended.
Click to expand...

I agree on the tti's, I have put them on several cars, but too expensive for this build.

Haha, I understand that you're a little iffy! Thanks for your cam advice, but don't you think it will be a little too much for my needs? I have found out that I, for 99% of my driving, stay between idle and 3,000 rpm in this car. With that knowledge, wouldn't it be stupidity to put together an engine that doesn't work best in that range?
About my converter; I have some low stall original converters but I first thought my Hughes 2,200 stall would be more fun. Maybe I have to take that back since I want diesel characteristics...
 
well, I made the cam choice based on getting the most power out of the combo while retaining power in the cruise range with the 3.23 gears and 275 tires which comein about, 28 inches?
The next cam down would be so bad ether.

Your idle time is just that. Idle. Not really moving. And if so, through the parking lot?
Cruise speed. The cams listed RPM range is 1400 and up. It will pick up some over 2200 and feel all right from 2500 and above, where you'll be driving at, on the Hwy.

So, is it stupidity? The idea of a cam not being flexable enough or a car/engine/drivetrain set up not being flexable enough is not seeingthe big picture. IF you feel my suggestion isn't fitting and I fall under the stupid, OK fine. I'll accept the insult and carry on. Sorry for bothering you.
 
HP2 said:
About my converter; I have some low stall original converters but I first thought my Hughes 2,200 stall would be more fun. Maybe I have to take that back since I want diesel characteristics...
Click to expand...
The 2200 converter has been my biggest question here. It will work..... but throws away much of the low RPM advantages that you want. I would for sure be putting in a stock one. I used one with a 190/445/114 cam (a high lift, low duration, economy and stump puller cam from the first gas crisis era in 1973-1974) in a 351C and the cam and TC were well matched for towing, good mileage, etc., and it would still rev and pull hard to over 6k with headers, good head flows, and a single plane manifold....all the wrong parts, right? LOL
 
You must log in or register to reply here.
-

Back
Top