cam question

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MattyP

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finally picked out this regrind, curious if the stock 302 heads will handle it or will I need springs and guide boss modifications, what do you guys think?
HR-286-SBMd Long Snout LA

Advertised Duration
In. 286
Ex. 298

Duration @ .050
In. .227
Ex. .234

Valve Lift 1.5
In. .480
Ex. .480

Lobe Lift
In. .320
Ex. .320

RPM
1600 - 5400

LSA
112
 
get the right springs ………. and that cam will flow more than your stock 302's...
 
I'm gonna port them a little I think, I have valve grinding equipment too so I could put bigger valves in no problem, I've read the 302 heads flow pretty good for 318s thou
 
I'm gonna port them a little I think, I have valve grinding equipment too so I could put bigger valves in no problem, I've read the 302 heads flow pretty good for 318s thou
If you work with the heads a little and install the correct springs, you'll be fine.
 
It's kinda funny when you look through the comp cams specs, they have some similar dual pattern cams but with way more lift
 
Matty what is the lift at your advertised duration
that looks like a lot of duration for that amount of lift for a HR
did they say it was a "sausage" or a GT or any other clues what it was mastered from?
 
Matty what is the lift at your advertised duration
that looks like a lot of duration for that amount of lift for a HR
did they say it was a "sausage" or a GT or any other clues what it was mastered from?
that's all the detail they give really, other than the description, which is as follows
Street * Increase low end and mids * 9:1+ compression, intake, headers, gears * 2000+ stall * Choppy idle
 
Matty what is the lift at your advertised duration
that looks like a lot of duration for that amount of lift for a HR
did they say it was a "sausage" or a GT or any other clues what it was mastered from?

I have a old Erson Cam TQ30H Dur @50 .226/.226, Lift .465/.465, .111 lsa
New in box never run with lifters, I'm wanting to put it in a mild 340 and see what happens.
 
Erson will have a little better than stock 340 cam (timing is completely different- more lift)but still way obsolete
Matty who's dooing your cam
keep us posted
you are running a carb and some more compression or what?
most regrinds that I have worked with are not that much duration
interested
thanks
 
Erson will have a little better than stock 340 cam (timing is completely different- more lift)but still way obsolete
Matty who's dooing your cam
keep us posted
you are running a carb and some more compression or what?
most regrinds that I have worked with are not that much duration
interested
thanks
It was on ebay $160 some cam grinder in dallas, I'll let you know how it runs, going in a 70 dart, aiming for 9:1 or a little over on compression, and yes carbed
 
It was on ebay $160 some cam grinder in dallas, I'll let you know how it runs, going in a 70 dart, aiming for 9:1 or a little over on compression, and yes carbed
Go with Oregon Cam Grinders for a lot of better options. I’m sure it’s the cheaper as well.

Jake
 
To answer the question, yes you will need springs, not sure how big the boss is on those...but everything on that head is tiny (I can't even get my fingers in the intake ports), so, I would plan on having to work on it.

JMO, but that cam in a 318 with 302's will probably be a dog at low RPM, and not much better up top. Those heads are ok on stock motors, but they just don't flow (hence they don't like much cam)...and again, in my opinion are not worth putting ANY money into for performance gains.
 
To answer the question, yes you will need springs, not sure how big the boss is on those...but everything on that head is tiny (I can't even get my fingers in the intake ports), so, I would plan on having to work on it.

JMO, but that cam in a 318 with 302's will probably be a dog at low RPM, and not much better up top. Those heads are ok on stock motors, but they just don't flow (hence they don't like much cam)...and again, in my opinion are not worth putting ANY money into for performance gains.
does the 112 lobe separation help the low end power over a cam that has tight lobes? I was kind of under the impression that lobe separation helps a bigger duration cam have better low end, hence the description that the grinder gave saying lows and mids? idk also does a head need to flow really good on a smaller displacement like a 318? I'm not building a stroker here or anything
 
Yes, a bigger Lobe separation number will mellow out a cam. The lower the number, the choppier the idle.
 
application?
engine size?
At what lift is the advertised spec'ed at?
for street, My opinion:
from 4000 to 5500 it will pull reasonably nice, even at just 9/1.
prepare to buy a big TC and gears in the 4s, and buy shares in a gas company, cuz you are gonna be burning a lot of gas. 3500 with 4.10s @5% slip, is about 27mph with an A904 .
Don't be using a factory TC cuz the wait will be unbearable. Nor anything less than 3.55s with anything less than a 2800TC, cuz with 3.55s, 3500 is about 31 mph and the engine is just coming up to the torque peak, which at 9/1 is still gonna be really soft.
On the street I think yur not gonna like it.
As for me;
even with a 360 I know there would be times, combo'ed as above, that I would hate that cam. With a smaller engine comes bigger hate. From 227 to 286 is 59* of clearance ramp. While slow even for a roller, this by itself means nothing, cuz we don't know how far that valve is still open or rather how close to closed it is. If that spec is at .008 or .006 tappet rise holy cow that is sad. But if that is at .002 or .001 well then it is only semi-atrocious for performance.
But I can tell you that even if the .006 tappet rise was 10* smaller, that cam would still be a dog under 3000rpm in a 318@ 9/1 Scr. So you might as plan on a 3000TC just to get off the line.

And don't even think about marrying this cam to a 318/A833, with any street gear, at only 9/1.
Am I being an azzhole? sure. Better me an azzhole than you spend $2500/3000 putting this prideNjoy together, only to watch a stock smogger teen with a 2800 and 3.91s blow your doors off.
 
This is going into a 70 dart with a 904, converter is 3000 stall, rear is 3.23 for now, I have a super short commute so I'm not particularly concerned with street ability. I'm coming from the land of oldsmobiles, my last car was a cutlass g body with a similar cam and it ran really good, it was a 403 cube motor thou
 
Also I'm being cheap, this is a regrind so I'm not expecting miracles, if it doesnt work for my combo I'll get a different cam no biggie, right now I'm contacting the seller on Ebay gonna ask for the next step lower cam you guys have scared sense into me, I'll keep you posted
 
Also I'm being cheap, this is a regrind so I'm not expecting miracles, if it doesnt work for my combo I'll get a different cam no biggie, right now I'm contacting the seller on Ebay gonna ask for the next step lower cam you guys have scared sense into me, I'll keep you posted
MattyP, I'm about an hour west of you, just south of Rt. 81. I have a customers 318 in the shop right now that I'm building with mildly ported 302s. Just some bowl work and gasket match. I just ordered a custom hydraulic roller cam, and it is along the lines of 209/217 @.050 and .465" lift, on a 112 LSA with a 107 ICL. That is about where you want to be for that combo, unless you are definitely going with a gear change. With 3.55s, you can go up another 4 to 6 degrees @ .050 on the duration.
 
You mighta missed the point;
You could probably find IDK 10 different 227* cams with 10 Different advertised specs and they may run from poor to gangbuster in your engine. And the lower your Compression ratio is the softer they can be out of the gate. You have to be really careful if you have a low-C 318, there is almost no room for error and then you get a soft combo. The 3000 is a step in the right direction; but this changes with torque input, so if you have a 3000TC spec'ed for a 10/1 engine, it may not be a 3000 in an 8/1 engine. It all depends on how much cylinder pressure the engine makes. Nevertheless, a 3000, whatever it is, will probably allow a decent hi-rpm cam.
The problem is the 3.23s
If you plan on keeping them, then say you had that 227/234/112@.050 cam, that might power peak at around 5300rpm. With 27" tires this is gonna be around 50 plus mph. So if the bottom end is soft (because the late-closing intake fails to trap the mixture because it doesn't close until the piston is nearly half way back to the top), and it doesn't spin, then it's gonna be a long, long time before you get to the power. With such a late closing intake, the engine will be in reversion to mid 2000s, so thank goodness for the 3000stall TC. The torque-peak might be around 3800 so in first gear that might be around 37mph, again, if the bottom is soft , don't bother flooring it at much under 30 mph.

But say you found a 227*roller that was only 265* advertised @.006tappet rise. Same .050, same 5300rpm power-peak, but now the intake is closing 21/2=about 10* sooner, and trapping easily 10 more psi cylinder pressure. That would be worth more than one cam size as to a stronger bottom end.
But the power-peak problem still remains; if it doesn't spin, it's a long wait to get up on the cam.

So you have a few options
1) is a smaller fast rate of lift cam to pump up the pressure and thus the torque, and the earlier, smaller, powerpeak all combine to take off harder while peaking earlier.
2) increase the compression ratio, to increase the cylinder pressure, to affect an across-the-board performance increase.
3)get some bigger gears to increase the power to the road by torque multiplication, making the engine act like it's bigger. This has the double-whammy bonus of bringing the Speed down at the powerpeak. For instance; that same 5300 peak with 3.91s brings the speed down to 42 mph from the earlier 50+, and by 60 the rpm has risen to 4440
4) get a bigger engine that already has a stronger bottom end by virtue of cubic inches.

Just remember, as soon as you hit second gear with a torqueflite, the rpm falls to 59% .If you carry that 5300 rpm peak out to 5900, then the Rs will fall to 3480, and so yur engine better have some pull in her to get back up on the cam; again it's a long way to the torque peak at ~3800, and 60 mph in second will be ~3700. So yur kindof shooting yourself in the foot if yur looking for low ET from zero to 60. That 227 cam will be great in first gear, but then it's sortof over.
Roller-cams are NOT like FTH cams, and 318s are not 403 olds engines; there is absolutely no comparison.
If you want to keep the 3.23s, and if you have a Low-C 318 ,then you have to be really really careful; and the cam is NOT the place to cheap out.
 
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Also I'm being cheap, this is a regrind so I'm not expecting miracles, if it doesnt work for my combo I'll get a different cam no biggie, right now I'm contacting the seller on Ebay gonna ask for the next step lower cam you guys have scared sense into me, I'll keep you posted

I used to run cams that I got from a speed shop sponsor. When that deal ended, and I was broke, I called Chet Herbert in California.

I told him what I was running in my Ford and he laughed..."That's a damn Chevy grind". He regound a core for me and sent it out, Best perfoming cam I ever had in those 351's!
 
i run ported and matched 302s with 1.60 exhaust valves on my 360, it keeps pulling til i back off at 6000, with the 284/484 in a 318 with these heads it would wind up to 7000 no problem. with present cam ,489 lift from bullet racing and previous MP cam i ran comp 901s as per engine shop recommendation.these heads will flow with good velocity, never mind the number crunchers, try things out for yourself and see what happens
 
i run ported and matched 302s with 1.60 exhaust valves on my 360, it keeps pulling til i back off at 6000, with the 284/484 in a 318 with these heads it would wind up to 7000 no problem. with present cam ,489 lift from bullet racing and previous MP cam i ran comp 901s as per engine shop recommendation.these heads will flow with good velocity, never mind the number crunchers, try things out for yourself and see what happens

7k?
901 springs, 484 cam & 318 heads..
In neutral? floating'em. Lol

There are too many people that hung up on the 302 head... it's just a closed chamber 318 head.. it flows 170's cfm intake and 120's exhaust. All as cast 318 heads are great for stock cams up to 340 spec, after that they need work or your power return from a bigger cam will be drastically reduced.
Random food for thought...

Did you know a #675 318 head is around 68 cc?
Did you know that a #302 is 64cc?

If you were to mill down a 360 head to 68cc...it would be the same as a 675 open chambered 318 head....and flow 25cfm or so better.
If you milled a 360 to 56-57cc... it would be closed now like a 302, and flow 25+ cfm more.
The 302 head is just about 4 cc smaller than a 675 open chamber head from the factory. I have them both off low mileage bone stock motors, wire wheeled the carbon off and cc'd them. No sunk valves.
The bolt on power increase is tiny till you incorporate a tight quench with the right piston, then it goes from tiny to small..add a cam and port them and maybe you will then see....it is about air flow! Ultimately the power is gained by getting more in and out.
Given a choice, unless it's a mild stock rebuild, if it is going to make power over 5000 rpm... I will never use a 318 head, period.
273 cid is the only exception.
 
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