Thanks for the info, I will definitely keep it in mind. I wanted so bad to use the NPI heads, but O well wasn't ment to be. I may use them for another build, but my mind needs to be made up before I order parts for it.
Project-97
- Thread starter AStangThang
- Start date
To all the cam experts out there, this is for someone learning about our factory cam gears, and how they can be beneficial and a aggravation. I've searched far and wide for any good influences or ideas when it comes to locking the factory gears to not move when daily driven & being operated under abnormal conditions (pedal to the metal).
For all who are getting ready to tackle the job of swapping cams soon or someone reading this post 5 years from now, I would like to show you how I obtained my stranglehold over the factory gears from possibly moving down the road.
First off, by now you have learned that our engines can be out (degree wise) from the factory by many degrees, but most are within 6* from each side. The growing consciences is that the "RH" Passenger side cam is advanced, and the "LH" Drivers side cam is most of the time retarded, some cases its spot on.
In my setup, I will be installing camshafts from Modular Head Shop, known as their NA Gen2 Stage2 , but I don't like using the word "stages" as a clarification, so get out of the habit of doing so! Mine are ground by Comp Cams at 224/226 duration .556"/.535" @.050, kinda smaller for a "Stage 2", most companies would indeed call these a "Stage 1" lol.
Anyways... what I'm getting at here is that my "RH" Pass. Side cam gear, which is know for its advancement, was as far as I could get it to move by the factory key way (Full Retard)
, lifter lash set at 0 lash. With Cam gear being full retarded by factory conditions, it still allowed for the MHS (.556" lift/ 224*In. dur. @ .050 110 ICL) camshaft to put my Intake Valves fully into the pistons, and stop me from rotating the engine. Also keep in mind that I had -.010" took off the valve margin to match my heads being decked -.010", using a used factory HG which measures at .036" crushed, on top of a untouched factory 4.6L block torqued to spec!!!!
Carefully go over the math, now...how many degrees you think that cam gear was advanced? Something to think about huh? With that being said, I did a little test with the "LH" Driver side cam gear. Instead of "Full Retard" (which you should never do!) Lol JK!.... Using the same system as above, I installed the "LH" Driver side cam gear all the way advanced, and it never kissed not the 1st piston. Pretty interesting huh? These camshaft gears that I used was off a 2006 Crown Vic. So the cliche of being newer, doesnt mean there more accurate, so remember that if your romanging for parts at your nearest parts yard. These pictures here, are to show how I'm keeping my camshaft from moving around, see the keyway. I bought extra stainless steel feeler gauges to cut up into tiny rectangles. I inserted these according to how far I need to move in either direction, and to fill the void on the opposite side of gear. By no means can these come out, unless the bolt & washer backs out, then that would be the least of your problems.
I will say thi for my application, and yours may differ somewhat from mine, but should be close though, within thousands. Whatever the measurements where when I moved the gear, the end of the valve was always .003" less than the total movement of the cam gear. THIS SHOWS HOW TIGHT OUR VALVETRAIN TOLERANCES ARE.
/EXAMPLE/ If I mmoved cam gear .010", it was .007 at the valve. If it was .005", it was .002 at the valve. NO MATTER THE DIRECTION, ADVANCED OR RETARDED!
I took many hours, probably in the 30-40 hours to go over ever inch of valve train operation.
One last thing, and this is my findings.
EACH DEGREE I MOVED THE CAM GEAR, IT WAS WORTH BETWEEN .015" TO .017.5" OF MOVEMENT AT THE VALVE! (2* WAS WORTH .030"-.035)
I MUST ADD THAT PROPER LASH WAS ACHEIVED BEFORE I TOOK READINGS, SO BE SURE THAT ALL TOLERANCES ARE MET BEFORE PROCEEDING WITH THE MEASUREMENTS I HAVE SHOWED YOU. Sorry for yelling!
I ENDED UP TAKEING AN EXTRA .035" OF THE VALVE MARGIN AFTER ALL MEASUREMENTS WERE TOOK, BRINGING THE TOTAL OF VALVE MARGIN REMOVAL TO .045". THIS WILL GIVE ME PLENTY ROOM FOR CAMSHAFT ADVANCEMENT.
THESE PICTURES SHOW THE FEELER GAGE RECTANGLES I MADE, AND THEM INSTALLED BETWEEN THE GEAR & CAM KEYWAY. ALSO SHOWS THE .045" I TOOK FROM VALVE MARGIN.
SO BY MY CALCULATIONS, THE EXTRA VALVE MARGIN WILL GIVE ME ANOTHER 2*-2.5* OF ADVANCEMENT. OVERALL I CAN INSTALL MY CAMS AT A 107* ICL & 110* ECL, WHILE MAINTAINING A .030" OF PTV. THIS WILL GIVE ME A MIDRANGE BUMP, WITHOUT SACRIFICING THE TOP END.
For all who are getting ready to tackle the job of swapping cams soon or someone reading this post 5 years from now, I would like to show you how I obtained my stranglehold over the factory gears from possibly moving down the road.
First off, by now you have learned that our engines can be out (degree wise) from the factory by many degrees, but most are within 6* from each side. The growing consciences is that the "RH" Passenger side cam is advanced, and the "LH" Drivers side cam is most of the time retarded, some cases its spot on.
In my setup, I will be installing camshafts from Modular Head Shop, known as their NA Gen2 Stage2 , but I don't like using the word "stages" as a clarification, so get out of the habit of doing so! Mine are ground by Comp Cams at 224/226 duration .556"/.535" @.050, kinda smaller for a "Stage 2", most companies would indeed call these a "Stage 1" lol.
Anyways... what I'm getting at here is that my "RH" Pass. Side cam gear, which is know for its advancement, was as far as I could get it to move by the factory key way (Full Retard)
, lifter lash set at 0 lash. With Cam gear being full retarded by factory conditions, it still allowed for the MHS (.556" lift/ 224*In. dur. @ .050 110 ICL) camshaft to put my Intake Valves fully into the pistons, and stop me from rotating the engine. Also keep in mind that I had -.010" took off the valve margin to match my heads being decked -.010", using a used factory HG which measures at .036" crushed, on top of a untouched factory 4.6L block torqued to spec!!!!Carefully go over the math, now...how many degrees you think that cam gear was advanced? Something to think about huh? With that being said, I did a little test with the "LH" Driver side cam gear. Instead of "Full Retard" (which you should never do!) Lol JK!.... Using the same system as above, I installed the "LH" Driver side cam gear all the way advanced, and it never kissed not the 1st piston. Pretty interesting huh? These camshaft gears that I used was off a 2006 Crown Vic. So the cliche of being newer, doesnt mean there more accurate, so remember that if your romanging for parts at your nearest parts yard. These pictures here, are to show how I'm keeping my camshaft from moving around, see the keyway. I bought extra stainless steel feeler gauges to cut up into tiny rectangles. I inserted these according to how far I need to move in either direction, and to fill the void on the opposite side of gear. By no means can these come out, unless the bolt & washer backs out, then that would be the least of your problems.
I will say thi for my application, and yours may differ somewhat from mine, but should be close though, within thousands. Whatever the measurements where when I moved the gear, the end of the valve was always .003" less than the total movement of the cam gear. THIS SHOWS HOW TIGHT OUR VALVETRAIN TOLERANCES ARE.
/EXAMPLE/ If I mmoved cam gear .010", it was .007 at the valve. If it was .005", it was .002 at the valve. NO MATTER THE DIRECTION, ADVANCED OR RETARDED!
I took many hours, probably in the 30-40 hours to go over ever inch of valve train operation.
One last thing, and this is my findings.
EACH DEGREE I MOVED THE CAM GEAR, IT WAS WORTH BETWEEN .015" TO .017.5" OF MOVEMENT AT THE VALVE! (2* WAS WORTH .030"-.035)
I MUST ADD THAT PROPER LASH WAS ACHEIVED BEFORE I TOOK READINGS, SO BE SURE THAT ALL TOLERANCES ARE MET BEFORE PROCEEDING WITH THE MEASUREMENTS I HAVE SHOWED YOU. Sorry for yelling!
I ENDED UP TAKEING AN EXTRA .035" OF THE VALVE MARGIN AFTER ALL MEASUREMENTS WERE TOOK, BRINGING THE TOTAL OF VALVE MARGIN REMOVAL TO .045". THIS WILL GIVE ME PLENTY ROOM FOR CAMSHAFT ADVANCEMENT.
THESE PICTURES SHOW THE FEELER GAGE RECTANGLES I MADE, AND THEM INSTALLED BETWEEN THE GEAR & CAM KEYWAY. ALSO SHOWS THE .045" I TOOK FROM VALVE MARGIN.
SO BY MY CALCULATIONS, THE EXTRA VALVE MARGIN WILL GIVE ME ANOTHER 2*-2.5* OF ADVANCEMENT. OVERALL I CAN INSTALL MY CAMS AT A 107* ICL & 110* ECL, WHILE MAINTAINING A .030" OF PTV. THIS WILL GIVE ME A MIDRANGE BUMP, WITHOUT SACRIFICING THE TOP END.
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Ive got some what of a little update. I ended up buying some Coyote rods for the next project I will be doing. Its a 97 Teksid, just changing out the rods, and probably keeping the factory pistons in it. If I end up changing pistons it will be some mod max oem replacements. Anyway that's about it, on to the garage.
After work I ended up getting the rest of my timing set off, camshaft, and got some valve seal to retainer/keeper measurements. Took a cylinder to TDC, installed the valve spring tool and slowly pressed the spring down enough for the keepers to come out. Took out the springs, and pulled of the tool so I can get a clear look at the valve and seal together. Ended up getting a measurement around .135" from bottom of the keeper to the oil line where the seal doesnt reach, and around .090" to the retainer because it stick further down that the keeper.
Boostr1
Active Member
What are you doing now? What's with the measurements? Tryn' to figure this out...lol
I understand completely if I confuse everyone, I change my mind to much when doing something I care about.
Since day one ive been what everyone calls a "NPI Guy". I love the 'Ole mistreated and bashed NPI heads, and it shows in my decision making. What ive been trying to accomplish is an higher lift aftermarket N/A PI camshaft installed in a NPI head, .556" intake lift to be exact. This has been a debate from the late '90's, and as you see it still is today but .ost people just switch the heads out to PI's. I want to make it work because I know the capabilities of the NPI head in naturally aspirated form, I would almost go out on a limb and say that if your staying under 400rwhp that it is
. Yes I said that! Lol. Now in forced induction builds I say go ahead with the PI heads instead, but I'm not FI yet nor will I be for a while. Many big named people has made our NPI heads dip well into the 11's on a setup that can be street driven decently. Yes, the PI's have had that success also, but when a NPI does it, heads turn. Its a challenge, kinda lime the girl you try to date and she dont give you the time of day, eventually you take her out.
The big debate is true .550" lift, and I mean a true .550" lift lobe, not like Comps "OTS" cams that are listed as a .550" lift, but they measure in at a true .540" lift. My Cams are ground by Comp, but there MHS cam #'s which is a true intake lift at .556", correct .556". Many people have run the Comp cams w/ the .540" lift in their NPI heads w/ +.060" retainers installed so the valve springs won't have coil bind or what some call coil stack. Here's the thing, it's not the coil stack thats going to hurt me, it's the valve keeper/retainer to valve seal clearance. Its been said that keeper/retainer to seal clearance is limited to a camshaft w/ .560" lift, some others have said .570" lift. There lies what you see me doing, im pushing the limits to these #'s. Now here's the question, "Do I think I will clear?" Yes I do, but I want to know for sure how much clearance I actually have left. I want to be able to say w/o doubt what I have, so I can feel comfortable on my decision, and to give others confidence in theirs also.
Was the .560" clearance figured out on a bone stock totally untouched head? Was the .570" clearance figured out on a head w/ a valve job? Was the measurements done with factory valve or aftermarket valve seals? ECT.... I don't know yet TBC. Every alteration you make to the valve or seat changes all the measurements, and must be accounted for. I do have a valve job on my heads now, so it gives me some teeny tiny room.
Here's something to think about, Jim Cushman of Cushman Motorsports told me the other day that his .550" NPI cams are actually a true .547" lift, that's .007" bigger than Comps OTS cams, but it's .009" smaller than my MHS cams. Yep, I'm talking .009" lift more, but that's me and how I make decisions. I dont say the heck with it, I know for sure. TBC.......
It is official! I took great measurements today and found that a bone stock NPI head has .560" lift is the exact amount of room it takes for the valve retainer to physically touch the top of the valve seal. The valve keeper sits up into the retainer around .040", so when retainers touch the seal, the keeper still has room. If they both set flush together I could run my camshaft without any worry.
With the valve seal removed, I measured from the bottom of the spring pocket to the top of the valve guide, it measures .600". I measured the whole valve seal from top to bottom, it came to .805". The valve seal base is .040" thick, and the valve spring sits down on the seal base. The space between the seal and guide on the inside is over .100", so if we could get a shorter valve seal height, we would be able to run a higher lift in the NPI head, and not have to worry about anything except coil bind.
There's another way everyone can run a higher lift cam, change seat pressure, and change valve spring install height all at the same time. With that we could run the same valve seal as we do now with no modification to it. I will get into that in another post.
Just to sum things up my .556" lift cam is to close for comfort, and needs more clearance from retainer to seal. I would feel safe with .020"-.030" clearance, so let's get it there.
With the valve seal removed, I measured from the bottom of the spring pocket to the top of the valve guide, it measures .600". I measured the whole valve seal from top to bottom, it came to .805". The valve seal base is .040" thick, and the valve spring sits down on the seal base. The space between the seal and guide on the inside is over .100", so if we could get a shorter valve seal height, we would be able to run a higher lift in the NPI head, and not have to worry about anything except coil bind.
There's another way everyone can run a higher lift cam, change seat pressure, and change valve spring install height all at the same time. With that we could run the same valve seal as we do now with no modification to it. I will get into that in another post.
Just to sum things up my .556" lift cam is to close for comfort, and needs more clearance from retainer to seal. I would feel safe with .020"-.030" clearance, so let's get it there.
Boostr1
Active Member
I understand completely if I confuse everyone, I change my mind to much when doing something I care about.
Since day one ive been what everyone calls a "NPI Guy". I love the 'Ole mistreated and bashed NPI heads, and it shows in my decision making. What ive been trying to accomplish is an higher lift aftermarket N/A PI camshaft installed in a NPI head, .556" intake lift to be exact. This has been a debate from the late '90's, and as you see it still is today but .ost people just switch the heads out to PI's. I want to make it work because I know the capabilities of the NPI head in naturally aspirated form, I would almost go out on a limb and say that if your staying under 400rwhp that it is
Many big named people has made our NPI heads dip well into the 11's on a setup that can be street driven decently. Yes, the PI's have had that success also, but when a NPI does it, heads turn. Its a challenge, kinda lime the girl you try to date and she dont give you the time of day, eventually you take her out.
The big debate is true .550" lift, and I mean a true .550" lift lobe, not like Comps "OTS" cams that are listed as a .550" lift, but they measure in at a true .540" lift. My Cams are ground by Comp, but there MHS cam #'s which is a true intake lift at .556", correct .556". Many people have run the Comp cams w/ the .540" lift in their NPI heads w/ +.060" retainers installed so the valve springs won't have coil bind or what some call coil stack. Here's the thing, it's not the coil stack thats going to hurt me, it's the valve keeper/retainer to valve seal clearance. Its been said that keeper/retainer to seal clearance is limited to a camshaft w/ .560" lift, some others have said .570" lift. There lies what you see me doing, im pushing the limits to these #'s. Now here's the question, "Do I think I will clear?" Yes I do, but I want to know for sure how much clearance I actually have left. I want to be able to say w/o doubt what I have, so I can feel comfortable on my decision, and to give others confidence in theirs also.
Was the .560" clearance figured out on a bone stock totally untouched head? Was the .570" clearance figured out on a head w/ a valve job? Was the measurements done with factory valve or aftermarket valve seals? ECT.... I don't know yet TBC. Every alteration you make to the valve or seat changes all the measurements, and must be accounted for. I do have a valve job on my heads now, so it gives me some teeny tiny room.
Here's something to think about, Jim Cushman of Cushman Motorsports told me the other day that his .550" NPI cams are actually a true .547" lift, that's .007" bigger than Comps OTS cams, but it's .009" smaller than my MHS cams. Yep, I'm talking .009" lift more, but that's me and how I make decisions. I dont say the heck with it, I know for sure. TBC.......
Well, I guess that's the long and short of it...
I've looked and searched for measurements on the critical "retainer to seal" clearance, and only found 2 or 3 posts from the different forums as a whole. I wanted to help out the people who may not have certain tools to be able to do such measures, and by giving somewhat of a detailed description of the process, will help who want to run more than .540" lift in the NPI heads. What we need is some custom made valve seals, I'm going to be searching for some companies that may do it. They may do it, but say that we have to make so much at a time or we won't re-tool if they hae to. There's over .100" inside the seal between the valve guide.
Hey boostr1, do you run NPI heads on your car still?
I Recived my degree kit from MHS, and will playing around with it on this rainy day outside. It's a nice kit and not cheaply put together like some are. 18" wheel makes it cool, and I like it. Ford Racing High Volume Oil pump was in there as well, it will be replacing the 2v non-Ford unit.
Ive been here at the garage all day getting things ready and kinda getting the feel for the degree process until I get my new +.060 retainers in. I went to put my piston stop in and for some reason it will not even thread into the NPI heads, but it will go right in my PI's. The same spark plug will go in both heads no problem, so I'm going to shave the front down on the piston stop and re-cut the threads with my tap and die set, then we'll see how it goes. 
I ended up using my dial indicator for my TDC method, and I will show how I did that tomorrow morning, but I ended up with 145+81=226, 226/2=113 ICL. So I'm 3* off from where MHS speced the cam at 110 ICL. Not to bad for first try!
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Boostr1
Active Member
Nah, the pics in my build post with my car at the track was when I converted it to the full H/C/I PI swap. Now it has a MMR 03/04 Cobra shortblock with TFS heads and cams. What was strange, when I did the PI Head swap (they came of a Crown Vic) I used the PI cams from a 99+ PI Mustang, and for some reason the lifters were binding/ bottoming out, we had to send out the heads to a machine shop for them to machine the bottom off the lifter bore down. We never found out what it was. I mean I was new to this PI swap thing, and just read a bunch of stuff on forums and mags. Even my buddy who builds street outlaws and did the swap couldn't figure out why. Now reading your and @96blak54 threads I might have an Idea maybe why.
Screw that tool, go old school and stick a screwdriver in the hole...
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Nice setup then! Ive got a couple of other blocks that I will be building after I get this one back in the car. I like NPI's to much.
I would cut the bottoms off the valve seals and install them deeper onto the valve guides and glue them down.
My opinion is worth nothing.
My opinion is worth nothing.
After going over everything in my head yesterday evening I realized that I made a rookie cam degree mistake..and that was not locking the timing chain out..i used the tensioner as is and let it do the tension on the chain, no good!
Today I set everything up like I had it yesterday, except I used a C-clamp one the chain instead of the tensioner itself, which I took it off before starting the degree process. Now that everything was looking good I went ahead and started, this time now corrected it was 115.5* ICL, that's 5.5* away from spec at 110*.
Repeated the process, again 115.5*. Now time to move the Trick flow crank gear at least 6*, did just that and came out to a 110.25* ICL. I have a tad bit of play that I dont like, and thats in the crank socket that MHS puts in their Professional Degree kit. I noticed about a .5* each time I reversed direction when I'm doing timing @.050, and thats throwing it off. I would tend to think I'm actually between 109.75* and 110* ICL.
Next time I will be using some feeler gauge material between the keyway for 0 play.
Today I set everything up like I had it yesterday, except I used a C-clamp one the chain instead of the tensioner itself, which I took it off before starting the degree process. Now that everything was looking good I went ahead and started, this time now corrected it was 115.5* ICL, that's 5.5* away from spec at 110*.
Repeated the process, again 115.5*. Now time to move the Trick flow crank gear at least 6*, did just that and came out to a 110.25* ICL. I have a tad bit of play that I dont like, and thats in the crank socket that MHS puts in their Professional Degree kit. I noticed about a .5* each time I reversed direction when I'm doing timing @.050, and thats throwing it off. I would tend to think I'm actually between 109.75* and 110* ICL.
Next time I will be using some feeler gauge material between the keyway for 0 play.
That actually might work, I'm going to get my new vitons I have on my PI heads and see if they sit lower by any means, heck .020" would be great. If there the same size, I'm going to look into the option you laud out. This cam ia really making me work
#1 thing that's on my mind when I log in is the great support from this site and all its members. I want to say thank you to everyone for that, and to those members whom I've befriended, you know who you are, a special thanks to you for the great modular knowledge we've discussed, and friendship.
Now to today's events lol. I didn't get much done yesterday, but I did get all my imperfections out of my degreeing process, and remember practice helps alot!
I studied the 2v 4.6L degree process about a year prior to ordering my cams, and if any new comers are here looking at my build post, there's a YouTube video that a gentleman named Ken Collins made, his name on Youtube is "Bad Shoe Productions". He goes over the whole process quite nicely, from tools needed, to what, where, how and why. I myself do things a tad different, but I just wanted to share the great video with everyone who needs a little boost. Also, Andrew Lavender has a nice one also on the Tube.
What I ended up doing to the cam gear was to shim it with my feeler gauge material. By putting the feeler gauge to the right of the keyway advanced the camshaft. Here you can see the gauges on both sides of the keyway, and both are.024" each. These feelers can't come out because of the washer and camshaft.
I also had slop in the degree kit crank socket MHS sent me, I used an .011" shim gauge here.
Here you can easily see the .050" slop I was working with before, and this was the reason I had to move my Trick flow crank gear 6* advanced. Today I'm resetting the crank gear back at 0*, and going ahead with the degree process from the new positions of the crankshaft and the camshaft.
Now to today's events lol. I didn't get much done yesterday, but I did get all my imperfections out of my degreeing process, and remember practice helps alot!
I studied the 2v 4.6L degree process about a year prior to ordering my cams, and if any new comers are here looking at my build post, there's a YouTube video that a gentleman named Ken Collins made, his name on Youtube is "Bad Shoe Productions". He goes over the whole process quite nicely, from tools needed, to what, where, how and why. I myself do things a tad different, but I just wanted to share the great video with everyone who needs a little boost. Also, Andrew Lavender has a nice one also on the Tube.
What I ended up doing to the cam gear was to shim it with my feeler gauge material. By putting the feeler gauge to the right of the keyway advanced the camshaft. Here you can see the gauges on both sides of the keyway, and both are.024" each. These feelers can't come out because of the washer and camshaft.
I also had slop in the degree kit crank socket MHS sent me, I used an .011" shim gauge here. Here you can easily see the .050" slop I was working with before, and this was the reason I had to move my Trick flow crank gear 6* advanced. Today I'm resetting the crank gear back at 0*, and going ahead with the degree process from the new positions of the crankshaft and the camshaft.
joe65
Well-Known Member
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just read through your stuff. Your car reminds me of my 1st 00GT that was black. Good work on the heads!! I dont' want to be a party pooper, but i had convinced myself that any 2v build really should use the TFS heads. They are just so much better than any stock 2v head. But, i also know that they cost a shit ton and when anyone posts them used they get snagged really fast. Watching your build!
I respect your opinion brother, no harm done here
. Alot of people feel that way about our heads, but I'm going to throw you a curve ball, I'm actually going to use my NPI on this small build. I ended up buying a 4v engine for the Teksi, it has lower miles and maintained greatly by a nice lady, plus I just got coyote rods for it. So things changed drastically from my initial plans of the cam, PI heads swap, Bullitt intake, and long tubes. My current engine you see here is a 50K miles NPI motor that been remanufactured, and everything is +.010" from pistons to the head gasket. The NPI's bad issues was the single angle valve job (3 angle now), small cam ( .556" lift now), bad intake, (Bullitt now), and of course the exhaust (kooks now). I've taken care of all the NPI's picadelos, and not to many people run a true .556" lift cam in them. I think she will be close to 280rwhp, and it shocked everyone the way it is now, so I'm stoked!
I'm happy to have people watching the build, it's motivated me tremendously, all glory to
God for it! I love the trick flow heads! they would've been a great addition to the build but I started collecting parts about 4 years ago, and I could have bought a set here recently but I already had my camshafts waiting on me, plus I needed suspension parts along with everything else, so I had to spread the $ out lol.
I've personally always wanted a NPI car, since it came with one, lets make her run!
