Long duration cam in /6

[RustyDusty]

I really really really want that long duration cam idle sound. But I know it comes at a cost in your low end band. What all would I have to do to my /6 to make a long duration cam possible? It's stock at the moment, and I have all the time in the world to work on it. So let me know your thoughts!

 

[805moparkid]

well u need the rest of the motor to go with it, i.e. head flow induction, comp, yadda yadda yadda, but! i have a 246 @ .050 idles at about 1050 in N.

sounds really good with a super 44.

 

[805moparkid]

and vids
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[RustyDusty]

That is what I want!!! I'm jealous!!! When you say it needs the rest of the motor, what all needs changed? Pardon my ignorance, but what is that on your #1 intake?

 

[805moparkid]

That is what I want!!! I'm jealous!!! When you say it needs the rest of the motor, what all needs changed? Pardon my ignorance, but what is that on your #1 intake?

on the head is the outlet to upper radiator hose, on the intake itself is for water heating.

as for engines, u hear of people talking about a good "combo", this meaning that everything is balanced or designed to work with other components in the same performance level will say.

its like putting a big blower on a stock 273 or something with 25psi of boost... no more bottom, the engine was not built around the idea of boost.

so! what u need to do is decide what u want the car to do? 13 sec drag car that u can drive to work daily and know u'll get 12 mpg but dont care? or just a nice rebuild with some light upgrades?

p.s. i built mine to do low 13's and Mike Jefferies thinks it will to :cheers:

 

[RustyDusty]

That's an awesome set up you have. I'm not too worried about track times. I'd just like to smoke up the kid who ever dares to rev his honda at me. I really want that awesome glug glug idle.

 

[805moparkid]

That's an awesome set up you have. I'm not too worried about track times. I'd just like to smoke up the kid who ever dares to rev his honda at me. I really want that awesome glug glug idle.

well lope will come from duration, but just because u have a lopey motor dosn't mean it will start making power where u need it. ok, so duration is the amount of time that a valve is open, with lots of duration u get lope, but the more duration the high in the rpm band the engine will make power (to a point). becasue with more duration u get more overlap, so both valves open at the same time. so with over lap when the piston is moving up to start the comp stroke the intake is still open and u get bleed off @ low rpms.

so if u want just a fun Cruiser u dont want more than 230 @ .050 or maybe less. u can still make alot of power but it will be in a usable range, under 5500 rpm.

pm me for specs and what not...

 

[RustyDusty]

Thanks! PM sent

 

[805moparkid]

Thanks! PM sent

np

 

[RustyRatRod]

It's just like any other motor. Like moparkid said, yougotta have everything to match the camshaft. Higher compression, bigger valves, good head work includin port work, loose converter with an auto and deeper than stock gearing. The smaller the cubed motor, the more easily it is over cammed. In other words, a .240@ .050" camshaft will be much more radical in a slant than in a V8. moparkid has got you on the right track. BTW moparkid, that's a wicked soundin slant you got.

 

[805moparkid]

It's just like any other motor. Like moparkid said, yougotta have everything to match the camshaft. Higher compression, bigger valves, good head work includin port work, loose converter with an auto and deeper than stock gearing. The smaller the cubed motor, the more easily it is over cammed. In other words, a .240@ .050" camshaft will be much more radical in a slant than in a V8. moparkid has got you on the right track. BTW moparkid, that's a wicked soundin slant you got.

thx!!

 

[RustyDusty]

Thanks for all of the help guys. I'm stoked to get this under way. How do I match all the needed parts together? In other words, once I pick my cam, how do I get the numbers that I need for compression, valve size, etc?

Cheers,
Drake

 

[805moparkid]

well what cam are u gonna run, erson makes a 280/270 cam that i have heard is really nice!

but for startes ur looking at a 9.3-10:1 comp
oversized valves and lots of porting
high stall converter or bigger/better clutch
block work, bore and hone, line hone mains, oiling mods, decking of head/block.

before i get the head done i would figure out what pistons ur gonna run, if on a budget go to summit and get the .040/.060/.080 over pistons, i have part numbers for good rings on the .080.

get the bottom end loosely assembled before final hone! figure out ur piston to deck height measurement. then u can deck the block and figure ur compression. note: the more off the head the better combustion chamber shape.

is ur motor already bored??

 

[RustyRatRod]

I would imagine the stock 340 valve spring would suffice for most all but the most radical cams for your application. You can get a generic brand 340 spring for like 40 bucks.....course that'll be 16 and not 12, but that's ok. As for valve size, there's really only like one popular oversize I think it's like a 1.74 intake valve...i forget the exhaust size. No doubt you could go bigger, but first, I don't think it's necessary and secondly, you'd be lookin at more cost as that first oversize is really popular and inexpensive. As for compression, you just need to decide what you want there. the slant head will take a .100" cut off the deck surface real easy. Some folks go more. some take half off the head and half off the block. The end result is the same. I think going .100 off the head and them thin steel head gaskets like Charlie S has will get you around 9.5:1. that's plenty.

 

[RustyRatRod]

well what cam are u gonna run, erson makes a 280/270 cam that i have heard is really nice!

Good luck gettin them on the phone or to return emails. I just gave up. I'm either goin with that biggest Clifford grind or gettin somebody to custom grind one.

 

[805moparkid]

Good luck gettin them on the phone or to return emails. I just gave up. I'm either goin with that biggest Clifford grind or gettin somebody to custom grind one.

did they go under??

and the next cam people i would go with is Schneider in San Diego CA. one thig to is when u over bore it comp drops (more area). i took .110 off the head, the piston was .080 and .180 in the hole:wack:, and i still only had a 9.3 comp...
so since i have it apart im taking another .020 off the deck for a 9.8:1 comp

thats why u need to mock up the bottom end so u can figure the piston in the hole and then let us know!

 

[RustyDusty]

You guys are ridiculously helpful! I can't thank you enough. Well... choosing a cam, moparkid, you said in an earlier post

if u want just a fun Cruiser u dont want more than 230 @ .050

(which is what I'm going for)

When you say fun cruiser... will it still have a nice over cammed glug at idle? To me there is no greater sound than that. What cam do you have in your /6?

Also, what would a good cam in the 230 @ .050 range be?

moparkid, do you know what the popular oversized valve sizes are? Also, I thought boring had no effect on compression? Since you're not affecting the stroke length?

Strokerscamp, I've read a lot about really machining down these /6 heads. Is .100" the max you would go? What about .100 off the head, then a bit off the block?

 

[805moparkid]

You guys are ridiculously helpful! I can't thank you enough. Well... choosing a cam, moparkid, you said in an earlier post (which is what I'm going for)

When you say fun cruiser... will it still have a nice over cammed glug at idle? To me there is no greater sound than that. What cam do you have in your /6?

Also, what would a good cam in the 230 @ .050 range be?

moparkid, do you know what the popular oversized valve sizes are? Also, I thought boring had no effect on compression? Since you're not affecting the stroke length?

Strokerscamp, I've read a lot about really machining down these /6 heads. Is .100" the max you would go? What about .100 off the head, then a bit off the block?

and for valves go 1.7/1.44 SI valves is cliffords source but i think there are some on ebay.

as for the cam 320 lobe = 448 lift and 220-230 @ .050 104-108 LSA

don't by the double link timing chain from autozone, mine lasted 6k miles, invest in the roller master or jp

 

[Charrlie_S]

ok so stock is a 3.400 bore with lets has 54cc head and 0 deck (piston flat to deck surface) = 10.00 comp not actual numbers!!

and u bore it .100 over. so now is is 3.5" instead of 3.4. so u added volume but didn't make the squeeze any different. ur still compressing the same amount, but with more volume= less squeeze. make sense??

Using your numbers, and a .022 head gasket, with the 225 stroke of 4.125, the compression ratio is 11.52
Changing the bore to 3.500 the CR comes to 12.09

http://www.wallaceracing.com/cr_test2.php

Increasing either the bore and/or stroke increases the CR. Decreasing the combustion chamber size and/or head gasket thickness, increases CR

 

[805moparkid]

Using your numbers, and a .022 head gasket, with the 225 stroke of 4.125, the compression ratio is 11.52
Changing the bore to 3.500 the CR comes to 12.09

http://www.wallaceracing.com/cr_test2.php

Increasing either the bore and/or stroke increases the CR. Decreasing the combustion chamber size and/or head gasket thickness, increases CR

grr i messed up my thot process on that one thank u charrlie!

 

[Charrlie_S]

grr i messed up my thot process on that one thank u charrlie!

You're welcome. BTW, anytime I post something like this, I am not trying to put anyone down. It is to be considered "constructive". I am just trying to help someone from going astray. Anyone can make a mistake (even me ), and sometime it is just in typing. We can all learn from each other.

 

[66aCUDA]

and for valves go 1.7/1.44 SI valves is cliffords source but i think there are some on ebay.

as for the cam 320 lobe = 448 lift and 220-230 @ .050 104-108 LSA

don't by the double link timing chain from autozone, mine lasted 6k miles, invest in the roller master or jp

Dont use Clifford if you can help it. Use Engine Builder for the 1.70/1.44 SS drop in valves.
JMO
Frank

 

[805moparkid]

Dont use Clifford if you can help it. Use Engine Builder for the 1.70/1.44 SS drop in valves.
JMO
Frank

agreed on clifford cams!! ive gad friends have great luck with Schneider cams in San Diego CA

 

[RustyDusty]

Alright, thanks guys. I've got an idea with the direction that I need to go with this project. Where are some good places to purchase all these parts from?

 

[805moparkid]

Alright, thanks guys. I've got an idea with the direction that I need to go with this project. Where are some good places to purchase all these parts from?

haha here we go!

roller timing chain http://www.motorstate.com/
all bearings thru summit or machine shop (recommend durabond cam bearing)
pistons factory style .040/.060/.080 thru summit
any size piston rings thru kevin @ total seal 623-587-7400
cam thru racer brown or Schneider, no ersons any i guess??
Core plugs thru summit
head gasket thru Charrlie_S on Fabo
Intake/headers gasket thru 66cuda/Frank
intake thru clifford ( http://www.cliffordperformance.net/) or aussie (http://www.aussiespeed.com/)
Hooker Super Comp headers thru Summmit

that should get u going...