IHADAV8.com - Turbo Buick Tech, and Nonsense

Tech Area => General Buick Tech => Topic started by: blown1 on March 21 2017, 04:06:19 PM

Title: confused!
Post by: blown1 on March 21 2017, 04:06:19 PM
so I built and installed new engine in my 87 T,,   basic 3.8, 30 over, forged pistons,  oil pump blue print, TA  grooved cam bearings, comp 206 roller, T/A lifters, and pushrods,  pac springs (same specs as comp cams spec'd)  shim head gaskets,
( GM orig ) ARP head bolts,
and......... started with stock rockers,, broke a shaft, up graded to HD rocker shafts, put a push rod thru a rocker.
alot of valve train noise!
installed T&D roller rockers, WOW is this thing noisy!, 
I thought  possibly  coil bind,  retainer bottoming out,  valve hitting piston, so off came the heads, and  installed  lighter springs.
and checked every thing, no valve contact, no coil bind, no retainer hitting, .
so I installed them, and same noise.
I adjusted  the valves again, 
is it possible  the lifters collapsed?  or  not pumped up? as I found I could  push  the rocker down by hand, (on some)
top end is getting plenty of oil,
I'm ready to walk away  for a while,


Title: Re: confused!
Post by: TexasT on March 21 2017, 06:19:07 PM
What did you use for lifters?
Did you disassemble them and clean em out, then soak em before install?
Good break in lube? Did it fire right up or did you have to crank it a lot?
Have you pulled the vc to make sure oil is getting up there?
Title: Re: confused!
Post by: motorhead on March 21 2017, 07:11:26 PM
Did you try swapping in an LS1? ;) I kid... I kid.
Title: Re: confused!
Post by: good2win22 on March 21 2017, 10:21:44 PM
TA sells standard travel Morel roller lifters branded with TA performance on the links. I have found as well as others that the pre load on those lifters needs to be about a 1 and 1/2 turns after getting the slack out between the rocker and the lifter. It will quiet down at idle.  Measuring the travel on the push rod when doing this, it's a little over .060 preload. Those standard travel Morel lifters have I think a little over .130 of oil resivior. What oil are you running and what is oil pressure?  Also where is the feed for the oil pressure sending unit located? In the brass T or back of the block?
Title: Re: confused!
Post by: blown1 on March 21 2017, 10:43:01 PM
T/A  -morel  lifters,   no didn't  dissassemble em, using 10-30  dino oil,  60psi cold, 25 warm,

top end is well lubed,  in that oil  is pumping thru all rockers.

TT chip, and car fired with in 3 revolutions,

SO.........  your telling me  T/A lifters require  alot of preload? I've been setting them at 1/2 turn
 after  rolling the push rod,and it gets tight.

oil sender is in  brass block , by oil pump.

talk about  frustrating!

Title: Re: confused!
Post by: good2win22 on March 21 2017, 10:46:05 PM
T/A  -morel  lifters,   no didn't  dissassemble em, using 10-30  dino oil,  60psi cold, 25 warm,

top end is well lubed,  in that oil  is pumping thru all rockers.

TT chip, and car fired with in 3 revolutions,

SO.........  your telling me  T/A lifters require  alot of preload? I've been setting them at 1/2 turn
 after  rolling the push rod,and it gets tight.

oil sender is in  brass block , by oil pump.

talk about  frustrating!


Yes. Everyone I've talked to this week and last has said the same thing about the TA/Morel lifters, 1 to 1 1/2 turns of preload. My engine was noisy too. Don't get carried away though. You can actually bottom out the lifter and start opening the valve with the adjuster. Oil is good. Just add a bit more preload and see what happens.
Title: Re: confused!
Post by: earlbrown on March 22 2017, 02:11:01 AM
Before any lifter (tappet) is installed it needs to be put in a vise and squished. It's amazing the thick jizz that will shoot out on some of them and just how much force it takes to crack them loose.

Trying to tune around a stuck tappet can be nerve wrecking to those that don't realize just how gummy some of them can be.
Title: Re: confused!
Post by: blown1 on March 22 2017, 10:30:02 AM
1st, many thanks for the input!!!

well, sounds like I should of  cleaned  the new lifter PRIOR to  install,
oh well,  whats "another " intake gasket, LOL

odd part is, after running total time of maybe 30 min,  2 or 3  lifters still have not pumped up,
in that I can depress the rocker  with my finger, and feel the lifter  depress,

but... what is causing  the damage,  (push rods thru the rocker, and rocker shaft to break)
Title: Re: confused!
Post by: Forzfed on March 22 2017, 10:41:06 AM
Also, make sure that the roller tip of the rocker is right on top of the valve stem.  I encountered a problem with binding on the rocker shafts.  I had to remove one shim.  And I have crappy lifters! :x
Title: Re: confused!
Post by: blown1 on March 22 2017, 11:59:13 AM
sad part  is, I was over board  in checking  proper alignment on the tip, adjusted the shaft spacers,
 used blue dykem , and checked for  spring to rocker  interference.
alot of good that did,


Title: Re: confused!
Post by: earlbrown on March 22 2017, 02:54:55 PM
I really with the ''it's important to center the roller on the stem'' wivestale would go away.

Proper rocker arm geometry is NOWHERE near as easy as that.  I often wonder how many setups got made worse (or flat out wrong) by worrying about the sweep pattern.?


At the middle of the lift you want the rocker arms pivot points to be square with the valve stem.   Bigger lift means lower rocker mounting not higer.  that minimizes the width of the sweep pattern. Where it lands is purely trivial.


.....at that exact same time you want the pushrod to be square with the rocker but that's not exactly possible since Jim Miller holds a current patent on that 'technology' and he won't make Buick rockers. I've asked.  What I usually do is do that math on both sides then bisect the difference for the best happy medium.
Title: Re: confused!
Post by: blown1 on March 22 2017, 05:08:40 PM
well.      been in the garage all morning and part of afternoon,
checking everything,
AND..... adjusted the  valves.  but this time I backed them off until they had clearance,
 then added 1 & 1/2 turns!
when I started it up rattled until lifters  pumped up, then got  stupid quiet, (valve cover is OFF)
I started to laugh,
then did the other side,      kinda feel dumb., but  it would of been nice if T/A would of  mentioned this.
I called a buddy (no names)  who builds Buick motors, has a 8 sec  turbo buick, and generally  is upto date  on
 buicks.  he was very surprised, and added he usually builds solid roller cam motors.

SO. I guess I'll cancel the new flat tappet cam and lifters , LOL

now. if it'll  not breal anything , I'll be happy!

Title: Re: confused!
Post by: good2win22 on March 22 2017, 05:40:19 PM
Glad it worked for ya. I have been in valve train hell this last few weeks with mine.
Title: Re: confused!
Post by: TexasT on March 22 2017, 07:40:23 PM
Nice, way to keep after it.
Title: Re: confused!
Post by: blown1 on March 22 2017, 11:23:20 PM
still puzzled  about all the breakage,   rocker shaft,  3 push rods thru  rocker arms.
 could being loose valve adj cause all that?

had to go out and start it again, just to listen to the LACK of noise!  LOL

now, if nothing breaks !!!!!!!!!
Title: Re: confused!
Post by: blown1 on March 27 2017, 07:08:27 PM
I give up.
 still  noisier than I like,  have to run valve cover spacers,  and fiddle with them so rockers don't hit,
 then bang!  it breaks a rocker arm  hold down bolt, 
it gets better........ ..
 fix that,  start it,  another bolt  breaks,
these are grade 8 bolts,

so. I have decided  its going back to hyd flat tappet,  new springs, 
I have no idea what going on, but don;t care at this point,
its close to being pushed into the corner and ignored  for few months, 

so.. I'm  looking for 206 flat tappet cam , after this  experience, I'd prefer NOT a comp cam,
cam, lifters,  springs. head gaskets, Heck I'll even go back to stock type timing chain!

I get so pissed,  then I go start  the skyhawk ( same eng, 206 hyd flat tappet, ) and its  quiet,
start instantly, idles perfectly, 

screw this roller noisy crap!!   why are these so noisy? GM makes a roller cam 3.8 that silent,  are we,
 the buick  community, so ignorant , we can't  make these quiet?

wow, I guess I'd better  just shut up and go find a cold beer.
Title: Re: confused!
Post by: TexasT on March 27 2017, 08:35:10 PM
http://m.ebay.com/itm/Buick-231-3-8-3-8L-Hydraulic-Flat-Tappet-Camshaft-Cam-Lifters-Kit-1977-87-/200312033755?nav=SEARCH (http://m.ebay.com/itm/Buick-231-3-8-3-8L-Hydraulic-Flat-Tappet-Camshaft-Cam-Lifters-Kit-1977-87-/200312033755?nav=SEARCH)

I think Elgin is good stuff. I couldn't see the description. There was a split 204/214 on there the other day, that is where I'm kinda leaning.
Title: Re: confused!
Post by: good2win22 on March 27 2017, 08:43:27 PM
Can you load a pic of your cam card?
Title: Re: confused!
Post by: blown1 on March 27 2017, 11:34:02 PM
http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=46&sb=1 (http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=46&sb=1)
Title: Re: confused!
Post by: motorhead on March 28 2017, 09:39:19 AM
Not that I like repeating myself, because I don't - here goes:  Anything that comes out of Comp through a Vendor is old junk. Shitty lobe designs.  Poor base materials and workmanship. Oldtime valve event concepts.

See if Cam Motion will cut you a cam to suit your combo.

I really should take some time to decipher just what is going on with the classic Buick grinds.
Title: Re: confused!
Post by: good2win22 on March 28 2017, 10:24:39 AM
Something definitely wrong with your valve train setup to be breaking things.
Title: Re: confused!
Post by: motorhead on March 28 2017, 10:41:29 AM
Something definitely wrong with your valve train setup to be breaking things.

High Energy lobes? Those were first cut in what... 1995?  Nice smooth lobes exist today which don't beat up valvetrain.
Title: Re: confused!
Post by: blown1 on March 29 2017, 10:38:47 PM
well.   round 2 ( or 3 or4)  pulled the motor today,
will slowly dissect  it tomorrow,
but. ...  new cam/lifters, springs will be  here in 2 days,
cam is hyd ,flat tappet,  ( quiet)
no idea why  hyd roller  is so noisy, but  not any more! LOL


if you read this all post all the way  to this end........... .

in 3-4 weeks  I will have in my possession  some highly desired  wheels.
in 18x8 18x9 19x9.5       I not supposed  to  be letting the cat out of the bag.
but this is  over 2yrs working and struggling  to  manufacture  these.
they will not be cheap,  as  we have over $100k invested in these,
stay tuned for more  info, LOL

Title: Re: confused!
Post by: earlbrown on March 30 2017, 12:11:08 AM
I'd really recommend getting to the bottom of your bolt breaking problem.   If those hold down bolts aren't counterfeit they're rated at 150,000#s.   There's no way a hydraulic lifter, or 5/16" pushrod can flex the rocker shaft hard enough to break a bolt. Especially at idle.


Something's up with your head our shaft I'm guessing.


I'd pop the shafts out and verify the saddles are true, and verify the rocker shafts are straight (and see if the rocker shaft is still round at the bolt hole).  Are you running rocker shaft saddles?
Title: Re: confused!
Post by: motorhead on March 30 2017, 12:24:57 PM
Ramp rates on the lobes are a major part of the valvetrain noise issue, will be contributing to wear/breakage potentially as well.
Title: Re: confused!
Post by: blown1 on March 30 2017, 12:31:12 PM
yup, using support saddles on the roller rockers, but not on the  stock rockers,
breaking bolts on the  rollers,
putting pushrods thru the rocker on the stockers.

OH, I'm looking for ONE HD rocker shaft, the thick one, as I managed to break one,

today I'll be  carefully  taking the motor apart, to see where the screw up  is. ( besides me)

I didn't  think about  the grade 8 bolts being fake, came from the  local tru value hardware,

most of my bolts are from co called "Bolt Depot"   online,  now you have me thinking...... ...

going back to  206 hyd flat tappet  cam from elgin.

I'll  post up my results on disassembly .
Title: Re: confused!
Post by: Scoobum on March 30 2017, 07:42:09 PM
Has anyone tried one of these with 130 lb valve springs and stock rockers and had any success?

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=45&sb=2 (http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=45&sb=2)
Title: Re: confused!
Post by: blown1 on March 31 2017, 10:44:43 AM
1st, I'm a slow learner, and  usually takes 1 or 2 times  for me to get it.
I have a complete valve  grind/ seat grinding equipment in my garage,  including Rimac valve spring  tester.
I cut these heads for 1.71 intake and 1.51 exh valves, using ferrea stainless "hi flow" valves.
I cut both  valve guides down, (seals on intake only)
I tried  various valve spring  on these heads, started with  125 installed @1.72,  and 310 @1.20, with 313lbs per in spring rate.
then changed to 105@1.72, and 280 @1.20 , and 285lbs per in spring rate

comp cams recommends  105@1.80and 293@1.20, with 313lb per in spring rate.

tried stock rockers (HD/thick shaft)  broke rockers, and a shaft.

I have 7.950 pushrods, 8.00 push rods, and 8.050 push rods, all hardened ,
I tried all of them, no success.
I was using GM shim head gaskets, as I had about 20 sets stashed away, (.032 thick)

I thought I was careful in setup, as I used adj pushrod  to get my preload on the  lifters,

we've been with out power (elect) for the last 15hrs,  had hi winds (60 mph gusts).
so I haven't  been in the garage, to inspect   this pain in my ass.
but time is my friend, as us old /retired  grouchy  old fucks  have nothing else to do.

Title: Re: confused!
Post by: earlbrown on March 31 2017, 11:17:59 PM
Your setup is very close to mine. I have a 215/220 roller with thick shafts and stock rockers with a set of my shaft supports.  I was to say I have 125 seated and 350 over the nose. Same O/S Ferras.  I'm running beehive springs so I could possibly get away with a little less poundage.

I still have the factory hold down bolts with no breakage. I've never felt the need to upgrade them to some of my fasteners.

If your online bolt supplier is the one I'm thinking about, I can't say for sure, but you might have a bunch of Chinese crap.  Notice I can't come close to his prices with my bolt kits since I only use actual industrial stainless fasteners.

Where are your bolts breaking at?  Are they popping off under the head, where the threads meet the shank, or is the shank stretching to the point of failure without a clean break?
Title: Re: confused!
Post by: blown1 on April 01 2017, 11:04:08 AM
on the grade  8 -  5/16  bolts the heads pop off,  i thought maybe I was over tightening them .
 but upon loosening them , was about 35lbs, (I say about ,as I didn't use a torque wrench)

I'm thinking  that may be part of the problem.

I used a lock washer  under the head, ,partly to hold it tight, and partly to spread the load.
 the rocker spacers are made from a grade 5,  3/4 nut,  reamed to size,  the cut in half,  with 5/16 hole
drilled  in it, I matched  it with the T&D factory  spacers. same width,and ID.
Title: Re: confused!
Post by: TexasT on April 01 2017, 11:52:47 AM
I don't think a lockwasher is a good idea. It doesn't spread the force equally around the head and I think that is why the heads are coming off. I think some locktite(maybe blue, but that green and red stuff works too I guess) is a better solution to keeping the fastener in the hole.
Title: Re: confused!
Post by: blown1 on April 01 2017, 12:46:01 PM
 I thought the lock washer (when compressed)  would spread the clamping  load,
but,  stock bolt do not use any washer at all, but do have a shouldered bolt,

I think I'm going to test  some of the "grade 8" bolts I have,  torque wrench and a vice, see what
values  they  require to snap off.
Title: Re: confused!
Post by: motorhead on April 01 2017, 01:17:16 PM
Can Buick V6s fit larger diameter pushrods than 5/16"?  There is little added value in going to thicker wall thickness vs. larger diameter. There is also a lot of strength and stability to be gained (aka. resist pole vaulting valves) by going to a bigger pushrod, and there is not an attributable effect on valvetrain mass (weight over the nose of the rocker tip or mass of the valve).

I had a custom set of pushrods made by Trend to combat this issue in the wagon.
Title: Re: confused!
Post by: good2win22 on April 01 2017, 02:14:48 PM
Can Buick V6s fit larger diameter pushrods than 5/16"?  There is little added value in going to thicker wall thickness vs. larger diameter. There is also a lot of strength and stability to be gained (aka. resist pole vaulting valves) by going to a bigger pushrod, and there is not an attributable effect on valvetrain mass (weight over the nose of the rocker tip or mass of the valve).

I had a custom set of pushrods made by Trend to combat this issue in the wagon.
Had an 80 year old machinist still working in the shop tell me to skimp on anything else you want but never on pushrods.
Title: Re: confused!
Post by: blown1 on April 01 2017, 04:50:12 PM
took it apart, slowly looking for anything out of place or odd.
 nothing, except broke another rocker are bolt,
so,  took  some new ones I had  and set the torque wrench at 30 lbs and snapped  it off first pull,
 this is 5/15 ,  broke at where threads end and solid bolt starts,

so tried another, this time at 25lbs,  hit 25 , was ok,  tried again, the head snapped off.
checked  US recommended torque  specs,  5/16, grade 8 is only 18 ft lbs

so....obviousl y chinese crap!  I'm guessing they are equivalent to  grade 3 , maybe?

but nothing out of the ordinary  on the valve train,  no wear marks anywhere,  checked cam timing, spot on.,
no valve to piston marks,but valves sure are close together,  again ,no  marks.

lifters look new (they are) pushrods  are spotless, no marks anywhere,
 rockers  show nothing,     
regardless, going back to  hyd flat tappet,  and 80 lbs springs,  (which I'll set up at 90 if possible)
and back to setting pushrod length, again!

Title: Re: confused!
Post by: Steve Wood on April 01 2017, 07:36:11 PM
Factory spec was 25 lb ft according to the manual.  I would be scared to death to go past 20, myself.  Also, I would much rather use studs in this application-particularly if I were using the support saddles.
Title: Re: confused!
Post by: Just a Six? on April 01 2017, 09:03:33 PM
I had oversize push rods made for my roller setup from Manton http://mantonpushrods.com/ (http://mantonpushrods.com/)
I think they are 11/16 on my stock heads without any mods to fit. Very easy to deal with & shipped in 48 hours.
Title: Re: confused!
Post by: Just a Six? on April 01 2017, 09:05:28 PM
Might have been 11/32 now that I think about it?
Title: Re: confused!
Post by: Steve Wood on April 01 2017, 10:14:05 PM
11/32's would be correct :)
Title: Re: confused!
Post by: motorhead on April 02 2017, 09:29:09 AM
11/16" would be impressive.
Title: Re: confused!
Post by: Just a Six? on April 02 2017, 01:36:12 PM
11/16 would be rather large now wouldn't they!  :icon_eyes: 
Title: Re: confused!
Post by: reality on April 02 2017, 03:46:48 PM
http://ls1tech.com/forums/dynamometer-results-comparisons/1256314-dyno-results-11-32-pushrods-vs-5-16-pushrods-also-5psi-tire-pressure-diff.html (http://ls1tech.com/forums/dynamometer-results-comparisons/1256314-dyno-results-11-32-pushrods-vs-5-16-pushrods-also-5psi-tire-pressure-diff.html)
Title: Re: confused!
Post by: TexasT on April 02 2017, 05:41:13 PM
I can't see why you couldn't run larger pushrods, though one might have to do some grinding on the head for proper clearance. I would think there is enough "meat" on the head for that. Just one more thing to do with fancy cool guy parts.
Title: Re: confused!
Post by: earlbrown on April 03 2017, 02:28:38 AM
I had to put my heads in a mill for stock sized pushrods to clear.  Turns out the holes aren't anywhere near concentric with the actual pushrod location.


I put layout dye on the VC rail and used a small square to located both sides of the pushrods.  Then put a 3/8th hole where they actually belong.   I have a sinking feeling a lot of the ''my lifters are noisy'' posts are actual pushrods kissing the heads.
Title: Re: confused!
Post by: reality on April 03 2017, 07:05:28 AM
If you are running roller rockers you could change the spacers around to suit.  Careful not to lose the needle bearings
Title: Re: confused!
Post by: blown1 on April 04 2017, 03:38:59 PM
OK.......... I'll admit  I F'd up ........

I believe I found the issue.
tore the heads apart  and found smashed seals,  didn't have that issue before adding 1.65 rockers,
and marks on the exh guides (which I did NOT cut down)
puzzling?  well it seems when I was  doing set up, I used  the stock Buick retainers, and everything  looked good,
when I assembled I used new fancy retainers, and...... there almost .100  lower,
so spring pressures were  thru the roof,  or in my case , thru the rockers.
and  add in 1.55,   to 1.65 ratio rockers, and everything  is screwed!


that explains why the  rocker bolts were breaking (beside cheap bolts)
the exh retainers were hitting the top of the guide, snapping off  bolts, rocker shafts,  making
spears out of  pushrods!

so after cleaning up will start over , and CHECK EVERYTHING!!!!!!

thanks for all the suggestions,  it did help, in that I am now  believer  in check twice, or 3 or4  times, and
assemble once!
Title: Re: confused!
Post by: Be4u on April 04 2017, 08:27:23 PM
making spears out of  pushrods!
lol, my imagination kicked in bigtime.

Glad you figured it out. Now you got a cool story to tell, I was all over this waiting for the verdict.  :rofl:

I was like "daaamn, he's bustin' heads off the bolts?!?! WTF?" Everyone else was non-shalont, I was trippin'!
lol too funny.
Title: Re: confused!
Post by: good2win22 on April 04 2017, 10:34:23 PM
Good to hear you are making progress and didn't give up.
Title: Re: confused!
Post by: motorhead on April 05 2017, 08:43:32 AM
Any potential internal lifter damage from collapsing them?
Title: Re: confused!
Post by: blown1 on April 05 2017, 11:08:11 AM

not  sure on lifter damage, haven't torn em down yet,

Robert... I'm sure your not the only  one kicked back, watching  the stupidity unfold.

I have no idea why I didn't cut  the exh  guides  when I did the intake guides.

there was no rush , or time frame  for me to get this done, so I do not have any excuse for
not  doing it  correctly, I could  say it was old age, making me forgetful,  (I'm 68)
but for some reason , it didn't occur to me to do them both, DUH.
oh well, live an learn,
Title: Re: confused!
Post by: Just a Six? on April 05 2017, 01:29:42 PM
There was a local Buick shop that did my engine many years back & he used the wrong size keepers so as soon as I gave it any boost (or high revs) a push rod would bend like a banana. I know it happened 10+ times as I had to pick up some spares from another shop. It always happened on the driver side & usually one of the same two of them always bent 1st. As soon as they did the boost gauge would go Nuts. I could swap one out in 5 mins after the 6-7th time sitting on the side of the road. Finally he agreed something was off & called after a few hours with the story. Crazy stuff happens for no good reason so glad your problem is solved!
Title: Re: confused!
Post by: blown1 on April 05 2017, 02:41:46 PM
cut all the guides down  to .675 tall,  i used a .500  OD cutter , also have a .530 OD cutter (two most common for  seals)
measured   the different  retainers,  installed  on my heads  stock retainers are 1.730
the  steel after market retainers  installed a 1.675.

measured  the  ID, and seal OD,  seat  dia,
coil bind,  seat pressures,  open pressures,
with and with out shims,  and....... travel available between ret and top of guide,

whew,  anyone think of anything else to measure?

next......... push rod  length,
Title: Re: confused!
Post by: good2win22 on April 05 2017, 09:14:17 PM
Just curious what your measurements are and the cam lobe you are going to use this time.


Installed height
Coil bind
Cam lobe
Rocker ratio
Locater to top of seal distance
Seat pressure
Pressure over the nose
Title: Re: confused!
Post by: motorhead on April 06 2017, 08:25:06 AM
Getting the pushrod length spot on is key.  I'd add installed valvestem height to the mix as well, especially if the seats were modified or the valves have a funky length.
Title: Re: confused!
Post by: blown1 on April 06 2017, 10:02:02 AM
well, right now I'm leaning toward a hyd  flat tappet cam,
the roller rockers  are such a pain in the butt,   (valve cover actually)
so with that in mind.
installed ...1.730
coil bind....1.121
lobe lift......in-.280/ex-.295
rocker ratio...1.55
seal to guide.......76 4 (actually guide to retainer) seal is approx .060 thick)
seat
Title: Re: confused!
Post by: blown1 on April 06 2017, 10:06:05 AM
 well, right now I'm leaning toward a hyd  flat tappet cam,
the roller rockers  are such a pain in the butt,   (valve cover actually)
so with that in mind.
installed ...1.730
coil bind....1.121
lobe lift......in-.280/ex-.295
rocker ratio...1.55
seal to guide.......76 4 (actually guide to retainer) seal is approx .060 thick)
seat  85lbs@1.730" class="bbc_email">pressure...... 85lbs@1.730
open/ nose  pressure... didn't measure,  advertised is 250lbs@.500

lobe lift is advertised at- int-.280 and exh .295, cam card reads  valve lift int .448, exh .472,
when you do the math.... it is not the same ?  int -.280x1.55=.434,  exh -.295x1.55=.457.

valves are  ferrea stainless steel, standard length, under cut,  1.77 int, and 1.51 exh
not sure of the weight,   but will know in a bit, (I'll weigh them)
Title: Re: confused!
Post by: blown1 on April 06 2017, 10:06:50 AM
sorry for the double post,
suddenly part of the post  dissapeared?
Title: Re: confused!
Post by: blown1 on April 06 2017, 10:23:32 AM
using my wife's postal scale (it s all I have)
SS int  valve......3.5 oz
SS exh .............3 .4oz

stock int........... 3.7oz
stock exh.........3. 5oz

new stock in.....3.7

stock retainer ....  .7
aftermarket ret..   .7
Title: Re: confused!
Post by: good2win22 on April 06 2017, 09:18:11 PM
well, right now I'm leaning toward a hyd  flat tappet cam,
the roller rockers  are such a pain in the butt,   (valve cover actually)
so with that in mind.
installed ...1.730
coil bind....1.121
lobe lift......in-.280/ex-.295
rocker ratio...1.55
seal to guide.......76 4 (actually guide to retainer) seal is approx .060 thick)
seat  85lbs@1.730" class="bbc_email">pressure...... 85lbs@1.730
open/ nose  pressure... didn't measure,  advertised is 250lbs@.500

lobe lift is advertised at- int-.280 and exh .295, cam card reads  valve lift int .448, exh .472,
when you do the math.... it is not the same ?  int -.280x1.55=.434,  exh -.295x1.55=.457.

valves are  ferrea stainless steel, standard length, under cut,  1.77 int, and 1.51 exh
not sure of the weight,   but will know in a bit, (I'll weigh them)
I did a run thru with your numbers and my calculations show it shouldn't be a problem hitting the guide this time even if it has .472 on the exh.  There is still .137 left until coil bind on the spring, so that is good too.


About the only thing I would suggest is an increase on the seat pressure.  Not sure what springs you have but I bet a few folks on here will agree with me, what you have is a little too light on the seat.



Title: Re: confused!
Post by: blown1 on April 06 2017, 09:50:54 PM
stock spring rate is 80lbs @ 1.72
what would anyone recommend?
 and what about  open, or @ .472 ?

the springs I have are  new/ stock springs.
Title: Re: confused!
Post by: good2win22 on April 06 2017, 10:05:08 PM
stock spring rate is 80lbs @ 1.72
what would anyone recommend?
 and what about  open, or @ .472 ?

the springs I have are  new/ stock springs.
I would start with comp 981-12. That particular spring is advertised at 105 at 1.700 and 273 at 1.250.  I know there is at least one other fella on this board with a flat tappet that runs a spring with quite a bit more seat pressure than this spring and he does it without issue.
Title: Re: confused!
Post by: Scoobum on April 06 2017, 11:47:53 PM
Watching this thread hurts. I run a 212/212 flat tappet with 130 lb valve springs with the stock rockers with solid shafts.We've swapped out prolly 2 dozen flat tappets over the years...and not one has gone flat. I was changing 981's 3 times a season...cuz they were goin' soft. I read a thread from Dusty Bradford when he raced these 109's back in the day...and he was swapping valve springs several times a season as well. Most don't run near enuf valve spring pressure...and usually buy a convertor that slips like a whore...and has the engine buzzing enuf RPM's to soften the springs in no time. Stick with a 208/208...210/210 or a 212/212 and the stock rockers with hardened or solid shafts and you won't run into issues. Start messing with valve train geometry...and all hell will break loose. I gave up trying to help people...as most prefer to struggle.
Title: Re: confused!
Post by: good2win22 on April 07 2017, 08:37:19 AM
Brad I was waiting for you to chime in on valve spring pressures.


Let me play the devil's advocate for just a minute. You mentioned that during a season you and Dusty were changing springs 3 times.  This brings to mind racing. Which would also imply lots of time at high rpm's albeit for short amounts of distance but still high revs. I have a sneaky suspicion that more spring pressure on a daily driver could possibly wipe a lobe on a flat tappet. 


By no means, am I an expert on this, but there is a compromise between racing and drivability.  The problem there in lies when we want both out of the same vehicle. Is it possible to run more spring pressure on a daily driver and get away with it and still have fun at the track? You bet it is possible. The next compromise is when you want to go faster at the track but still want to daily drive the buick.
It's a constant battle and you can't gain something without compromising something for it.


Good luck blown1
Title: Re: confused!
Post by: blown1 on April 07 2017, 10:00:00 AM
using a .060 shim, under the spring, I'm getting  98 lbs @ 1.73in
 that allows me sufficient  room for  coil bind,  and achieves  a lot better  spring  pressure.
 I'll have to see what  open pressure is, as I just did a quick check on this.

I doubt this car will ever see  a drag strip,  in the 17yrs I've owned it , it has never been there.

thanks for all the  help  you guys have offered, 
Title: Re: confused!
Post by: Scoobum on April 07 2017, 08:29:07 PM
I call bullshit on wiping a cam with a heavier spring. Most don't break a cam in correctly...an d we slather the living shit out of everything with break in lube. I overboosted this engine last year...and when pulled apart...checke d the cam and lifters. Surprise surprise...nor mal wear pattern. Best thing for a flat tappet cam after break in? Take it straight to the track...and beat on it like a seal pup. At 5500 shifts...the lifters will spin like Jack the Bear. Driveability.. .nonsense. This is a tight 2800 convertor...an d with Steve Monroes TB...it drives like a stocker. On a car that never saw the track, I'd go with 981's. Oh...and piss on double roller timing chains. Stockers work best.
Title: Re: confused!
Post by: Scoobum on April 07 2017, 08:42:34 PM
A quick word on the importance of good lifters...ya' pay for what you get. When I apprenticed at Custom Automotive Machine Shop we used shit ass jobber lifters. We used an old dyno with an oil feed line hooked to the engine...and spun an oil filter on it. We'd spin it up...and watch the to see how fast/slow the lifters were spinning. If one was spinning slow...then we'd grab an OEM lifter. Guess what? It'd spin so fast it was insane. My advice? Buy the best lifter money can buy.
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