360 camshaft for 8.4:1 engine

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360moparjunkie

360moparjunkie

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Now looking for flat tappet hyd. cam for our 360 motor.
Any good proven results out there?
Looking to make power up to 5300rpm range give or take.

Actual comp. 8.4:1
Using factor J heads w/ 1.88" intake
LD 340 alum. intake / dual plane

We don't want to loose all our bottom end and prefer to use factory stall converter.

Thank you all for the great support. Your help / advise has save us from a few headaches and few wasted dollars thus far.
You guys ROCK!:cheers:
 
with stock converter, Comp 262xe. Why are you wanting to keep the stock converter? A good higher stall converter is one of the best performance upgrades you can make.
 
Wanting to keep the stock converter isn't the issue.
Love to have more cool parts. If need be I'll make the investment.

Left the machine shop yesterday with an itemized price list and am a little blown away at the actual costs.

Looks like I can probably live with as many of my own existing parts as possible to keep the build going and still be able to put food on the table.

Looks like I can afford to have my engine balanced, repair any needed cyl. defects, purchase new cam, lifters, springs. Staying with my current rotating assy. I would like to spruce up the power end of the build staying within the confines of the 8.4 comp. and a poor mans valve train. (no special stuff making it super expensive)

I'd love to go full tilt and build a 408 but now is not the time. It's winter time and the economy/ construction is a little on the slow side this year so far.

Thanks for the help......I'll look at those cam specs.
 
forphorty, Comp cams XE268H numbers looks good. .477/.480 w/ adv. 268/280. 1600/5600 rpm. This cam may work well with the new rhoads lifters I already have.
Question would be if this cam is a little much for the 8.41 static comp. the motor currently has. If its too much....how much smaller?
How much would this cam kill the bottom end?
Also, cam card notation states that adj. valve train is needed.
If my factory stamped rockers will not work with this cam, then it's a deal breaker for me, as much as I do like the lift/duration numbers.

BB66, Thanks for the lead on the Summit K6901.(.441/.441 adv. dur. 276/286) This cam is sort of close to the cam we currently have, .410/.440. (dura. currently unknown) Cam card rpm range stated 200-4500. Would this cam make the motor fall on its butt @ 4500?

Thanks for the support.
 
I like the Lunati Voodoo cams especially if it's a low comp. engine. The Lunati 60401 would work real good I think but double check to make sure you have enough retainer clearance as the lift is rated at .475". They are a very fast rate cam which helps build cylinder pressure quickly. The Summit cam would probably work pretty good too. You mentioned it's not much bigger than what you have now but in reality it is quite a bit bigger if your cam is stock. Sure the lift isn't alot more but the duration is what matters most and it's a good 20 degrees at .050" bigger than a stock cam. Even though the Summit cam is rated to 4500 rpm I'd expect it to pull to 5000 decent. The ratings they give are just a general guideline and alot of other factors some into play to determine where it peaks at.

Most high perf. aftermarket cam mfg.'s suggest using an adjustable valve train but I have used stock rockers on perf. cams as big as your going. You just have to check the lifter preload to make sure it's in spec. and make sure the arms are in good shape. I've read another reason they suggest aftermarket arms is because the factory arms weren't real accurate on the ratio. Even though their spec'd at 1.5 ratio it can be as low as 1.37 to 1. That decreases the cam size a little and therefore you don't get as much perf. as the cam is rated at.
 
Fishy68, I"ll look into the Lunati 60401 @ .475 lift.

Current cam is not factory. Crower baha. Dont have a spec card on it, or a degree wheel (yet). So its hard to tell the diff. between summit .441 & mine.

Wondering how this cam would go w/ the Rhoads bleed offs I have.

How would I check lifter pre-load?

What is the best way to check my current rocker condition? (just visual or some type of numerical method using my dial indicator?)

Thanks again, and still learning!
 
Just to interject here... You cannot run used lifters on a new cam. So unless the Rhodes are still in a box, just buy a cam and lifetr set. None of the cams metioned will need variable duration lifters...
 
The Comp XE262 (218-224 @ 050) I run a very similar Crane cam in a lower compresion 318. (7.8-1) and it is fine. The rest of the set up on the car is a suregrip 3.21 and a 904 with sprinkled performance parts on the engine. Common stuff. Headers, 2-1/2 exhaust, (at the time) LD4B and a 625 carb.
 
360moparjunkie said:
Fishy68, I"ll look into the Lunati 60401 @ .475 lift.

Current cam is not factory. Crower baha. Dont have a spec card on it, or a degree wheel (yet). So its hard to tell the diff. between summit .441 & mine.

Do you know the part or grind # of the Crower cam? If so you might be able to look it up on their website.
Click to expand...

Wondering how this cam would go w/ the Rhoads bleed offs I have.

As Moper said you don't really need variable duration lifters with a small cam. But if you go with a larger cam like the 268XE it might be beneficial since it's pretty big for the low compression you have. In fact that might be the hot ticket if the Rhoads lifters work as good as they claim.
Click to expand...

How would I check lifter pre-load?

You need a dial indicator set up on the pushrod end of the rocker arm. Leave the rocker shaft a little loose and make sure the cam lobe your checking is exactly at the bottom (no lift). Slowly tighten down the rocker shaft with one hand while using 2 fingers to spin the pushrod being tested. As soon as you feel friction stop and zero out the dial indicator then torque down the rocker shaft and read the dial indicator to see how much the lifter was loaded. That is the amount of pre-load.
Click to expand...

What is the best way to check my current rocker condition? (just visual or some type of numerical method using my dial indicator?)

You can check the ratio but it isn't easy and won't really do much good as all stock arms will be comparable. I'd suggest just a real good examination of their physical condition. If there are any stress cracks or the area of the rocker that contacts the shaft is worn much or the shaft itself is worn much they need replaced. If they look good they should be fine.
Click to expand...

Thanks again, and still learning!
Click to expand...

Good luck
 
The XE268 would be a good cam, but I wouldnt get any more aggressive. I run this in my near stock compression 318 with headers, 2500 stall, 3.21 gears, Eddie 600 carb. It has a great sound and lope and has good power. It is a little soft under 2500, but pulls very hard above that all the way to 5500 rpm. I would say either the 262 or 268, but the 268 is not much more aggressive, so go with it.
 
I'll stand up and tell ya the Rhoads lifters worked great for me.

I have used them on a large cam to tame it down before.
Another build has them on the intake side only. It's a single pattern cam that cam without lifters. The duration, 236@ 050, is a bit larger than needed with a heavy car, stock high stall converter and 3.55's.

According to Rhoads;

Rhoads Original hydraulic flat tappet variable duration lifters are famous for increasing low-end torque, engine vacuum, and idle quality on engines equipped with performance hydraulic cams, while maintaining maximum top-end power. Better fuel economy and improved emissions quality are often reported by customers with Rhoads lifters. The unique construction of Rhoads Original hydraulic lifters reduces lift and duration at idle by approximately .010 in. to .020 in. Duration is reduced by approximately 10 to 15 degrees. Total lift and duration are restored at approximately 3,500 rpm. Original Rhoads lifters are also anti-pump-up for higher rpm revs. Typical vacuum increases range between 1 and 3 in. Rhoads lifters can be used with either adjustable or non-adjustable valvetrains. Original Rhoads lifters, with their legendary "ticking" at idle, sound similar to solid lifters. These Rhoads Original series lifters are designed for use with high performance street, marine, or racing applications.
Click to expand...

This makes it a dual pattern down low and back to a single up top.
 
360moparjunkie said:
Now looking for flat tappet hyd. cam for our 360 motor.
Any good proven results out there?
Looking to make power up to 5300rpm range give or take.

Actual comp. 8.4:1
Using factor J heads w/ 1.88" intake
LD 340 alum. intake / dual plane

We don't want to loose all our bottom end and prefer to use factory stall converter.

Thank you all for the great support. Your help / advise has save us from a few headaches and few wasted dollars thus far.
You guys ROCK!:cheers:
Click to expand...

Two questions I didn't see that you had answered are: 1. What is the rear gear ratio? 2. What is the intended use of the car?

Wanting to make power up to 5300 rpm is at odds with the 8.4:1 compression ratio. It's easy to over do the cam and carburetion as the difference between one stick or carb is not that much more $ wise than the next step up. For the engine, it can mean the difference between having enough fuel/air mixture to do its work or drowning in it.

For what it's worth the 360 HP cam was 286-276-44º and .429/.444 lift. Mopar Performance still makes this cam (P4452782). IMO, this makes a good baseline for your cam decision. If your axle ratio is on the tall side, you may want a tamer cam. If you're willing to forfeit a little of the bottom end for a bit more at the top, then go a little wilder.
 
Fella's, Thanks for all the input.

Forphorty, Thanks for the low comp. 360 article. I've had this shown to me once before and was an awsome article. One that has me looking very close at the XE262 cam used.

Fishy68, The Lunati 60401 (.454/.475 adv. 256/262) looks killer as well. I am locked into using the rhoads lifters as they are new, and I already have them. I know this is making parts choice somewhat backwards. Boils down to the run what you brung budget build. How would this 60401 Lunati gell with the rhoads lifters I wonder?
And given the rhoads lifter combo, how would it compare to the XE268H (.477/.480 adv. 268/280)

Moper, You have established your reputation as well respected here @ FABO. Your input is super valuable IMO. I invite all potential cost effective options. Thanks.
BTW, Rhoads lifters are new still in the box. They are new. I need new lifters, so these are the ones we are using. Just need the correct cam for the motor. Also, we don't want expensive/flipped out valve train assy.

2darts, You make a good point about drowning out the motor. Don't want that. Gears are currently unknown and subject to change as project just got underway. Will know that info. soon.
Intended use of vehicle is for weekend use only. Vehicle will never see big mileage. May never even see the strip. Just want an economical healthy motor to have fun w/ on weekends.

Thanks all.
 
I think the comp xes are the best bet for your build,the 110 lobe sepeartion is good,either the 262 or 268,also using rhoads lifters with an agressive ramp can make alot of noise but also is a bit over kill since the cams designed already to give you better idle and vaccum.I used a xe274 in a 360 with 8.7comp,mild stall and 3.23s and it ran hard,no issues at all,just get the tune right and if your not already use the thin head gaskets to get the most you can.
 
I think the comp xes are the best bet for your build,the 110 lobe sepeartion is good,either the 262 or 268,also using rhoads lifters with an agressive ramp can make alot of noise but also is a bit over kill since the cams designed already to give you better idle and vaccum.I used a xe274 in a 360 with 8.7comp,mild stall and 3.23s and it ran hard,no issues at all,just get the tune right and if your not already use the thin head gaskets to get the most you can.

Lead69, Looking for the cam that will work best with my already purchased rhoads & 8.4:1. Current comp. was figured with an .0475 head gasket. I could re-figure with the .024 gasket. Any problems with the thin gaskets sealing? That just sounds a little risky to me. Never used a skinny one before.

What special valve train components / work did you have to run to use the comp. xe274?
What rpm did the motor really start pulling for you at?

Thanks for the input lead69.[/B]
 
If you want to save some money and still get a great cam all you have to do is figure out the specs of a cam you want and give them to either your local cam house or these guys http://www.deltacam.com/ I have used them for a ton of engines and have never been let down by their information, parts or anything else to do with them, they ship too!
 
360scamp,
More cool info. that I'm still weighing out. I've talked to a local shop that custom grinds cams here as well.
So many options.

Thanks for the input & thanks for sharing your cars.
 
Use MLS head gaskets from Cometic. you can get them at different thickness's Take a little off the heads too, they probably need a fresh cut anyways. Get that CR up a little!
 
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