i need help w/duster engine

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,knowing this you should be able to stack measurements and arrive close to a # for the other set-up.I don't think the motor knows or cares if you use clay or not after it will be the same measurement.
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ah...i just re-read this part....OK..i see your point now.
i can use my current cam profile as a base to check for values that are known.
then measure off of this to see if that allows for more clearence ..and where/at what point?
i can configure a profile or new profile ....
thats interesting...
if its installed at 107...which this cam is..
i can account for this also...
Ok i got more work to do.
thanks
Mel.
 
ok stock j or x heads only flow 520 540 any lift after that it would not flow id put the 508 mp cam in they run good
 
first page 2nd post.
I said
we havent picked one out yet..
the old one is

Purple Shaft Cam & Lifter Kit
Adv. Duration: .292°/292°
Dur. @ .050'': 248°/248°
Lift: .509''/.509''
Centerline: 108°
Basic RPM: 2600-6000 RPM
Bolt Pattern: 1-Bolt

i have Doug Herbert roller lifters..was shopping his site..
but ...i dont know exactly what to get...
i really want to put a roller cam in it...
mel.
Click to expand...

Mel.
 
mel there are a lot of things you have to watch for here if you don't want to be doing two or three times all the info so far is correct. how bout going with a 585 lift came and change your rocker ratio. you;ll want .100 on the piston to valve ..60 on the springs and at the retainer to guide. Remeber your doing these clearance checks at static rpm add 7000 is you know what i mean things happen.
 
Guitar, There are other ways as noted. However, not knowing where the existing cam is in relation to the piston, yes, I say check from 100° to 100°. Same reason when I degree I go .050 down the lobe. Really only a few degrees would work but the idea is to be sure.

Big... The valves are closest just away from TDC. You have to keep the dynamic relationship of the parts in mind when you think about it.

Mel, the heads flow 266, they have the potential for about twice that when matched properly. If you're making 496 you're basically there. If you had the lifter bores bushed any lifter assembly should work fine but they may not clear the bosses in the valley area. Grinding on a complete engine is not a good idea. But at this point I dont think you care. If the season's over... why are you rushing again? Dont forget you will need the right valve springs which will require valve spring seat work in order to use the springs the roller cam needs. Plus, you will should really replace the valves if they are not stainless as the roller cam will hammer the heads off stock type ones.
 
What ever the existing cam is , is of no importance. The rate of lift on a solid roller is radically different than a flat tappet hydraulic cam. Even if she knew every clearance and spec and how deep the piston is at TDC and the depth of the reliefs (which she doesn't) you still couldn't possibly figure out what kind of clearance she will have with the new cam. Clay is OK if you have a
.100+ inches of clearance but when you are getting down to the thousandths of an inch clay is woefully inaccurate. Is it .065 or .050, you just can't tell with clay and be 100% sure. When you are talking .060 of clearance, you better be damn sure it's .060 and not .048.

Either way I can't take this discussion anymore, some of you understand, some of you will never understand until you learn by experience. So be it. These can be some hard and expensive lessons.
 
we,re listening or some of us are and thank you for sharing with a simple layman
 
I can't lie here, this entire thread is over my head and other car guys tell me I'm pretty smart, especially for my age (20) But wow, props to you Melissa on being a (fast) girl in this sport, If I wasn't in Wisconsin I'd give you a hug and bow at your feet cuz I don't understand at least 72% of this thread. Hope you get it sorted out and I'd maybe clay the motor with your purple shaft cam back in it and see what kind of room you have but, I'm no genius like you and the people posting advice here.
 
I would really like this explained better as wigsplitter said I'm no genuis so please simplify this for everyone so we can learn.
 
Wigsplitter, you wrote, "One of you Magnum head guys should pm me about some brand new .600 lift springs I've got for sale."

Magnum heads have stupidly designed valve guide bosses that stick up out of the head far enough that if you try to open a valve more than .530", or so, the retainer runs into the boss and won't allow any farther opening than that. (.530")

In view of that fact, of what use would a .600"-lift valve spring be?

In order to use it, to take advantage of its capabilities, the heads would need to be removed and re-machined to allow the valve to open .600"+ to prevent the interference.

Am I missing something here?????????
 
Hey Melissa if you go to racingarticles.com about the twelth article down,read up on the cam master it will do what you want.
 
God.... you guys are so negative...??

actually they moved the guide up so less of it would be in the port..
this allows more air to flow and keeps it off the bowl roof
and still ...keeps the guide length to support the valve
we figured this out..when i was considering what heads to put on my
engine.
you just need to make room on top of the guide for clearence.
thats not stupid...just fixed an old issue ...its evolution....
I am no Genius..My Grandfather builds offshore boat race engines
and my Father is a Hydralic/fluid Engineer..and ive been around this stuff my hole life...My brother just graduated from MMI...
most all of this stuff is Math...so I understand it..its math... dont know what else to say.
My brother tells me to make sure this is just a hobby..not a carreer...but so far its fun...
there is alot i have no clue about..
i cant get a carburator to work right for anything?
and i hate the smell of gear fluid..

i am not in a hurry (someone stated that) i just want to stay straight forward

got to go.. Orthodontist app...
 
Melissa, I am talking about the spring seats, not inside the port. Do you know what springs you currently have? Singles? Single with dampner (is my guess...) or duals? Guitar's right about knowing with the new cam and every cam and engine being different. We just disagree on using clay... I dont ever run closer than .090" on the exh and .080 on the intakes. I trust my numbers and methods but the rest of the Mopar world certainly doesnt need to. I thought you were in arush because you were ordering stuff to get this done like tomorrow or something. I apologize if that was a misread. I ha dbraces for 4 years... it sucked but good teeth get you noticed :D.
 
Bill Dedman said:
Wigsplitter, you wrote, "One of you Magnum head guys should pm me about some brand new .600 lift springs I've got for sale."

Magnum heads have stupidly designed valve guide bosses that stick up out of the head far enough that if you try to open a valve more than .530", or so, the retainer runs into the boss and won't allow any farther opening than that. (.530")

In view of that fact, of what use would a .600"-lift valve spring be?

In order to use it, to take advantage of its capabilities, the heads would need to be removed and re-machined to allow the valve to open .600"+ to prevent the interference.

Am I missing something here?????????
Click to expand...

You're not missing anything, you're reading my signature lol. The springs are from when I was going to swap to magnum heads and run a .508 cam which with the 1.6 rockers I think came to like.548, can't remember for sure anymore. I was going to have the heads machined for it all to work but, plans changed(all 4 of my magnums were cracked) I found a deal on some X heads and a 340 so now I'd like to get rid of the brand new springs which MP says can be used with a cam up to .600 lift, MP has springs for magnums with cams up to 500 and up to 600, I was going to be over 500 so that didn't seem like a good plan. Sorry if this seems like a thread jack but I wanted to explain the situation, it's my signature, not something I typed in that post.
Proceed. . .
 
bigdemo1 said:
I would really like this explained better as wigsplitter said I'm no genuis so please simplify this for everyone so we can learn.
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yea props to us regular guys that got totally confused by the time we finished reading the third post! :cheers: Glad to see I'm not the only one that can admit he's lost and has run out of knowledge(happens to me more than I'd like)
 
holy heck..
she is right...

"Magnum heads have stupidly designed valve guide bosses that stick up out of the head far enough that if you try to open a valve more than .530", or so, the retainer runs into the boss and won't allow any farther opening than that. (.530")
Click to expand...

they did..they moved the whole guide up in the casting to keep it out of the port roof...
thats smart perception right there....girl....!

ill ask a few questions..
i have a very very similar engine as what you have.
they are even kb107 pistons.
***we need to know what your piston to deck hight is..(should have this data from assembly)
***we need to know if the pistons have standard as shipped valve reliefs or did someone make them bigger..you stated 2.02 intake valve.
stock length are they stock valves?
***springs dont matter to me..but installed height does..?
*** you need to find out how much "layers" in thousands of an inch were removed from the heads and block
You stated the heads are cast iron X heads? is this correct? you also stated you have .634" of lift to coil bind..so the guides have definately been cut.
i am thinking you get some spec's for a cam that you think youll want..( this will be based soley on flow graph of the ports imho)
and then put in the numbers and open the valves at these events while its assembled on the motor...(someone suggested light checking springs)
then open the valves at the extreme ends of the events...and see what your clearence is...
you may need tall valves for the proper spring heights....as roller need much more spring...although your running a solid lift flat tappit now...right..?
i am no expert..but thats a start...
cheapst.

ps ive had my fair share of carburator issues..lol......
 
This is exactly what I was trying to say!You don't need any of this if you have a cam doctor,apparently it will do all this for you.
 
ok now.. rollers are cool.. and yea u got it right.. mmmm u will be able to have a more agressive ramp on the cam, this will increase the time the inntake is open fully.. read tech on cams at huges.. mm anyways u wont bugger to worry of the valves hitting the pistons.. cus the higher lift than .550 will just hurt the flow rate.. just for an example http://www.shadydellspeedshop.com/jhead.htm .. now i flowed far worse on some old ported j-heads of mine.. but after .550 no more.. u will be bugged with the need of stronger springs when the agressive lift ramp will make the speed of the mass (valves, pushrods, locks and retainers) and could easily make valvefloat... the thing u have got right.. the increased valve speed and more open time (time with valves fully opened) will give ur heads more potential.. u may also add cuple of cc to ur plenum.. (spacer of some sort)
 
Wigsplitter 74 said, "You're not missing anything, you're reading my signature lol."

Sorry for the confusion; I thought it was part of the BB text.


And, thanks to Melissa for the explanation about the Magnum guides/clearance thing. I guess what they needed to do, was supply longer-stemmed valves along with the raised guides....

Nope; that might make it easier to build a 360 Magnum that is actually competitive with the LS-series of GM engines; we can't have that......

Why start something new, now????
 
I agree with guiter on this hole thread, sounds like he has been to the same school. Bottom line, pull the engine, mount it on a stand and go to work. Install your new cam and see for yourself what this thread bares. BT
 
Bill Dedman said:
Wigsplitter, you wrote, "One of you Magnum head guys should pm me about some brand new .600 lift springs I've got for sale."

Magnum heads have stupidly designed valve guide bosses that stick up out of the head far enough that if you try to open a valve more than .530", or so, the retainer runs into the boss and won't allow any farther opening than that. (.530")

In view of that fact, of what use would a .600"-lift valve spring be?

In order to use it, to take advantage of its capabilities, the heads would need to be removed and re-machined to allow the valve to open .600"+ to prevent the interference.

Am I missing something here?????????
Click to expand...


but but but... u dont want to go .600+ on a j head, not even ported max.. they just wont flow any more even with the ports and bowl ported... besides u need to cut down valve guides and grind room for dubble springs (witch u wil need to for an agressive roller anyways) mmm not for killing the fun tough but its the reality
 
NorwayCuda,

You quoted me, but I just wanted to make sure you weren't directing your comments to me, because I never mentioned J heads... just Magnum heads.

I'm not advocating anything here; just wanted to point out the retainer/guide boss interference problem at lifts over .530" on MAGNUM heads.... that's all...
 
Nope mate :).. no directions to anyone.. simply just that even j, x and magnums need some modifications to lift that much.. mmmm
 
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