Need help with a cam selection for swap

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chasonmarose

chasonmarose

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hey there I'm looking to do a cam swap in my warmed over 360.
It is as followed

.040 bored 360 block zeroed
2.02/1.60 valved heads ported and polished 65cc
Intake Holley strip dominator high rise
670 Holley street avenger carb
3.58 stroke crank
Kb107 hypereutetic Pistons
Chevy HEI STYLE DISTRIBUTOR
Long tube headers
Warmed over 727 with 2800 stall convertor
Rear end is 2.73.. Changing out this weekend to 3.90 with a eaton posi

Now the motor with the cam I have is a xe275hl and that prick is noisier than hell on the valves
So I am thinking about changing it to a purple nostalgia 292/299 .508/.508 comp cam
Now the motor is making Around 11:1 compression running on 89 octane fine
Is this a good choice? I want that radical idle and power at the same time so I can Burn the tires off the line and into 2nd gear

Any feedback be muchly appreciated

Chase
 

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............I think the new cam is a poor choice, will loose low end torque........y not find out how to cure the noise ur complaining about.........kim.......
 
is this primarily a street car? Because I don't think your power brakes are going to like the 292/299 cam very much.
 
That cam is "nostalgia" for a reason its an oldddddddd design much better cams out there,,
 
I have the same short block, but with Eddies. And +.005 deck on mine makes 10.7cr. I ran it with that cam for two summers with a 4speed. Tried almost every gear from 3.91s to 5.13. It sounded great. Had no bottom end. Power was up at 5000 to 6300ish. Very narrow window. I even bought a GearVendors gear-splitter and a 3.09 O/D box, and 4.30s,to tighten up the shifts. Thats the only way that cam worked for me, on the street. It was just too soft on the bottom. I liked to cruise that cam around 2200 to 2400 at around 28 mph. Thats were it sounded real nice through the Dynomaxers. But at that rpm, a stock 318 makes more torque( I imagine). I got rid of that cam, and never missed it.
-My next cam was a Hughes fast rate(year 2001), 223*(HeH2330IIRC). What a difference. I put the 3.09Direct4th tranny back into it and a set of 3.55s. Then with 295/50-15s, that motor would break the tires loose in second,at almost any speed up to 45mph. Well, when the oil companies took the Zinc out of their formulas, they failed to send me a letter, so the cam promptly dropped 2 lobes. Enter cam#3.
-My 3rd and last cam is now a Hughes fast rate 232*. (HEH3237IIRC)I lost a bit of torque below 3000 or so, but gained a bunch of power up top. After a great deal of tuning, I got some torque back.It will again break the 295s loose at 25mph in 2nd. IMHO Thats a real nice size of cam for a stick car with 3.55s. And it takes the 3500#racewt Bcuda to 93 in the 1/8th. So thats a bonus. It doesnt idle with a wicked rumble like that big Purple cam, but its a much more liveable cam. Oh yeah, its much easier on fuel too.I love this cam. I might consider one cam size smaller if this one dies. I think my Dcr will allow it. And maybe add a couple of degrees to the LDA, and as much lift as I can get.
-With an auto,a high stall,and 3.91s, you might/probably will, get away with that 292/509. But I agree with others here, that there are much better grinds available.
You will love that engine. Just the right size.With the aluminum heads Ive always run mine on 87E10, with full timing, and no detonation.
PS; FWIW, my pb Booster worked fine on all my cams even that purple cam.
 
Well what would ur guys best opinion to go with for something that will hit the power range at about 2500 and have a really radical idle I don't care about gas mileage its a carbureted toy lmao
 
if you want sound get a Thumpr, if you want max power then don't. A Muthr Thumpr would work with your stall and has an rpm range of 2,200-6,100 rpm. Since its a toy and you're not really opting for the "best" choice but rather the one with the most radical idle I don't see a problem with going this route. A lot of people will say don't get a Thumpr because they're designed for sound and not performance. But it sounds like that's pretty much what you want lol
 
What about this its comps xe284

284/296 power band is 2300-6500

I want power and a rough idle
 
chasonmarose said:
What about this its comps xe284

284/296 power band is 2300-6500

I want power and a rough idle
Click to expand...

is there an issue causing your xe274 valvetrain noise other than steep ramp angles?

just wondering because the xe 284 is another comp cam.....what are u using for valvetrain
 
A set of nice thick cast aluminum valve covers and an underhood pad will tame the valve noise. Make sure the noise isn't due to some sort of setup issue.
 
chasonmarose said:
hey there I'm looking to do a cam swap in my warmed over 360.
It is as followed

.040 bored 360 block zeroed
2.02/1.60 valved heads ported and polished 65cc
Intake Holley strip dominator high rise
670 Holley street avenger carb
3.58 stroke crank
Kb107 hypereutetic Pistons
Chevy HEI STYLE DISTRIBUTOR
Long tube headers
Warmed over 727 with 2800 stall convertor
Rear end is 2.73.. Changing out this weekend to 3.90 with a eaton posi

Now the motor with the cam I have is a xe275hl and that prick is noisier than hell on the valves
So I am thinking about changing it to a purple nostalgia 292/299 .508/.508 comp cam
Now the motor is making Around 11:1 compression running on 89 octane fine
Is this a good choice? I want that radical idle and power at the same time so I can Burn the tires off the line and into 2nd gear

Any feedback be muchly appreciated

Chase
Click to expand...
There is your valve train noise...
 
LOL, no doubt that's an issue. 11-1 iron heads?

You have problems my friend. To much compression and not enough cam & stall & gear & carb.

Drop the ratio one full point and run what ya got.
 
-I did the math on your combo, and get: 10.5cr. Thats 65+5++8.4+0(heads,eyebrows,gasket, and deck, and With 748swept.
Thats (748+78.4)/78.4 =10.48 cr

Heres the thing; most streetable cams in the 220* to 245* range will torque peak around 3400 to 4400 rpm, and peak power falls around 40% later, give or take a bit; so in the range of 4800 to 6100 So the power band is from the torque peak to the power peak , plus what ever over-run your tranny needs to stay on the pipe; generally 600 to 1000rpm. So to stay on the pipe with the small cam,and a close ratio 4 speed, you could be shifting out at around 5400, to come in at 4200. And to stay on the pipe with the larger cam and a wide ratio, you could be out-shifting at 7100 to come in at5100.
So what does that mean?
Well a strong running 318 with a short period cam can make more torque at 2500, than a long period cam in a 340, and maybe in a 360 as well,at that same rpm, and very possibly, several hundred rpm higher.
The FIRST point Im getting to is this; When a cam manufacturer throws out a power range number beginning at 2500 you might be tempted to think POWER when you should perhaps be thinking TORQUE.
Unless your pockets are deep;Power at the top almost always trades away torque at the bottom. And for street running, big torque at 2500/25mph with good traction, is a combination that is very hard to beat. This is 4.10s @1.92 second and 27" tires, with a stick car, and not too much different with your tranny/TC.
With 3.55s and a 2.66 low the POWER with the 292/509 doesnt hit til 43mph.With 4.30s and a 3.09low it hits at 30mph. But nobody cruises in 1st gear. So the second gear math puts the hit at 49mph with 4.30s(1.92 2nd). And this puts the engine at 2500/24.5mph. So that motor has to get from 25 mph to 49mph using TORQUE. You better have some there. The 292/509 does not.And most times the fooling around is done by 49mph anyhow because the car has probably been speeding for quite a bit, already.
So SECOND point is this; a streeter needs Torque at cruising speed.
I often think guys with street cars get carried away with the HP numbers.At under 50 mph the big numbers IMHO are over emphasized, at the expense of the much more useful, big torque numbers.If I live long enough, Ima gonna turbo a Teener. Reasonably big ft lbs, smooth delivery, and excellent MPGS, low maintenance, Drive it everywhere. I wish Ida had the money 15 years ago.But I digress.

Of course at the track, torque at 2500? who cares.
 
Question

What type of Rocker Arm assemblies are you using ?

Comp-Cams XE-275 HL "High-Lift' {Grind #20-275-4}
Lift ...................... .525"/.525"
Duration ................ 275*/287*
Duration @ .050" .... 231*/237*
Overlap .................. 62*
LSA ....................... 110*
Centerline .............. 106*

I assume, that you are using the #995 Dual Valve-Springs
Valve-Closed .... #115 lbs. @ 1.700"
Valve-Open ...... #336 lbs. @ 1.150"
 
I'm gonna put an 268 cam in and another question I put a high volume oil pumpin and I get 40 pounds cold start and now when it's warm I get only 10-30 from 1000-5500 rpm its a milidon high volume oil pump and all my bearings are lined up with the holes so why don't I get closer to 65 psi?
 
You might be trading a noisy valve train for a pinging engine if you aren't careful.

That's a lot of static compression for a xe268 cam to run on pump swill.
 
chasonmarose said:
I'm gonna put an 268 cam in and another question I put a high volume oil pumpin and I get 40 pounds cold start and now when it's warm I get only 10-30 from 1000-5500 rpm its a milidon high volume oil pump and all my bearings are lined up with the holes so why don't I get closer to 65 psi?
Click to expand...

Which 268 cam?

Bearing clearances can cause low oil pressure. Since you have low oil pressure and noise I'd be looking beyond the cam and wondering if you have an oiling issue, like a missing plug. Have you pulled a valve cover to see if the top end is getting oil? Its one of the first to starve.
 
Yeah I'm with TXDart I think your problem is the octane your running , even 10.5 is too much compression for 89 especially since every 89 sold in Canada is cut with ethanol and very few people buy the mid grade most go cheap or go big eh! Try some of the Shell 91 it's ethanol free and is the best substitute I have found for the Chevron 94 I run in BC .I'm at 10.2 and I run the Shell on my cross country trips to Moparfest and it seems to be pretty decent as long as you can avoid the Flying J stations for some reason they have crappy 91 octane gas most of the time .
 
Put the XE274(.511 lift) in our 360 and it does seem to be very clattery. I don't really mind it because, I have the clearance set right and the motor has the 273 style rockers on it. As far as I'm concerned it's suppose to make those sounds but, if I didn't wanna hear'em I'd remove the mufflers and go racing.
 
BlueDream said:
if you want sound get a Thumpr, if you want max power then don't. A Muthr Thumpr would work with your stall and has an rpm range of 2,200-6,100 rpm. Since its a toy and you're not really opting for the "best" choice but rather the one with the most radical idle I don't see a problem with going this route. A lot of people will say don't get a Thumpr because they're designed for sound and not performance. But it sounds like that's pretty much what you want lol
Click to expand...

We tried one in my dads ride. They certainly have the sound. Performance was ok but not impressive for how radical the cam acts and sounds. It wasn't much fun on the street. His was the muthr thumpr.

Here is a cam that will give you the sound and performance you are looking for.

Crane #690141
[email protected]
.480 lift
106LSA

Personally if that engine were in my car I'd run this cam
Crower #31321
243/[email protected]
.521/.528 lift
112lsa
 
Im guessing you want to stay hydraulic, since you dont like the valve train noise?
 
Thanks guys I put the thumpr 279/296 in.. To my suprise it gave me that nice raspy idle along with the power I was needing! I tried it out on a little cruise with my 2500 stall convertor backed with 2.73 gears and it was a huge upgrade to what the 275/287 was! I thought for sure I was going to lose some torque and horsepower but to my suprise it was pulling harder than the cam I had in before. I have a 4 barrel 670cfm carb on and a Chevy style HEI distributor. After I came back my dad and I put my Muncie positraction with 3.91 gears and man what power... I can go through the intersection at 30 mph and step on it and go side ways with smoke peeling out the rear.. I think that people saying that the thumprs are more show than go are mistaken.. Unless the combination I am running is just perfect.. But thanks for all the feedback!
 
chasonmarose said:
I think that people saying that the thumprs are more show than go are mistaken.. Unless the combination I am running is just perfect.. But thanks for all the feedback!
Click to expand...

They sound more radical than they are is what people mean. My car makes the same power as my dads. His has a muther thumpr. Mine idles like a kitten, his sounds like a top fuel dragster. That's what people are saying. You can make the same power with better manners.
 
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