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 Post subject: This year
 Post Posted: Mon Dec 10, 2012 9:24 pm 
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Joined: Wed Apr 19, 2006 6:43 am
Posts: 1980
Location: Tell City, IN
Hey Guys been awhile since I was on the board regularly. (peace and quiet ha ha)
I ended up getting runner up in points by 5 points at the last race.
Anyway I broke something in the engine and just now had time to look at it.
I found a broken roller on one of the lifters, the lifter was using the axle to ride on the cam.
So I am taking it apart for a fresh plate hone, rings, bearings (they still look good so far)
New cam is what it has been needing and it will get it this winter. Also have bought a Victor Tunnel ram that has been fully ported and I will get a 2nd flying toilet so 2 toilets equal 2800cfm
should get all the air it can handle. The thing barely fits under the 6" cowl hood.
Need to do some more work to the suspension as well. Hopefully all goes well and make some good HP from this engine.. thanks for reading.

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6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post subject: Re: This year
 Post Posted: Mon Dec 10, 2012 9:34 pm 
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Joined: Wed Dec 06, 2006 9:24 pm
Posts: 5071
Location: Elizabethtown, KY
I was wondering how you did. That is one thing I'm leary of going with a roller, a broken roller. Good luck with the twins. \:D/ \:D/ \:D/

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6.7772 @ 101.51 1/8th 10.747 @ 122.24 1/4

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 Post subject: Re: This year
 Post Posted: Tue Dec 11, 2012 10:01 pm 
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Joined: Tue Jun 10, 2008 1:27 pm
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Location: Letellier MB Canada
Tunnel ram and injection, oh ya!! \:D/

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 Post subject: Re: This year
 Post Posted: Fri Dec 21, 2012 5:27 am 
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Joined: Wed Apr 19, 2006 6:43 am
Posts: 1980
Location: Tell City, IN
Time for a big camshaft too... Old Cam 264/274@.050 with .650/.620 lift new cam 278/290@.050 and .754/.652 Lift. Will install at 108° What will this do I wonder...?

_________________
6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post subject: Re: This year
 Post Posted: Fri Dec 21, 2012 6:03 am 
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Joined: Wed Apr 19, 2006 8:20 pm
Posts: 5852
Location: N.J.
us7race wrote:
Time for a big camshaft too... Old Cam 264/274@.050 with .650/.620 lift new cam 278/290@.050 and .754/.652 Lift. Will install at 108° What will this do I wonder...?




Slow it down???? =;

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running E85
Best ET 8.07
Best MPH 170.71
Barry


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 Post subject: Re: This year
 Post Posted: Fri Dec 21, 2012 1:13 pm 
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Joined: Wed Apr 19, 2006 6:43 am
Posts: 1980
Location: Tell City, IN
Would not surprise me.. I seem to have that kind of luck.

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6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post subject: Re: This year
 Post Posted: Fri Dec 21, 2012 1:44 pm 
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Joined: Tue Apr 18, 2006 3:20 pm
Posts: 1457
Location: Missouri
Are you going to spin it higher now? If I recall correctly you didn't want to turn it above some rpm due to bottom end or ???

Do your valves clear the pistons with that much duration?

Rick


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 Post subject: Re: This year
 Post Posted: Fri Dec 21, 2012 3:11 pm 
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Location: Tell City, IN
Hey Rick, I can spin it to 8000 if needed but dont think it will like it with the heads and the MCSA. The bottom end is Dart Block all 5 billet caps, 4340 crank, H-Beams with ARP2000 bolts.
Should be ok on RPM. The exhaust duration is fine but the intake valve only has .045 so not enough. I have the shortblock at the machine shop now for a review looks like it may have to be bored again have to mic it to see. So he will either cut the pistons to clear or we will be ordering new ones with the pockets already deep enough, that will help power because we will up the compression and go to the smaller rings pack than what I have now. We will see once he gets started on it what direction we will have to go. I would like to keep the RPM around 7500. May have to loosen the converter to get the best performance. Not sure yet.
Here are some more detailed cam specs...

Lash .016 and .030 HOT

.481 lobe lift intake
.4589 lobe lift exhaust

advertised duration 322/360
cam timing @.012 intake opens 53° BTDC closes @ 89° ABDC
Exhaust opens 112° BBDC closes @ 68° ATDC


cam timing @.050 intake opens 31° BTDC closes @ 67° ABDC
Exhaust opens 77° BBDC closes @ 33° ATDC
Max Lift 108° ATDC duration @.050 278°
Exhaust 112° BTDC durstion @.050 290°

_________________
6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post subject: Re: This year
 Post Posted: Sat Dec 22, 2012 8:22 am 
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Joined: Tue Apr 18, 2006 6:38 am
Posts: 11804
Location: Coming At Ya!
FYI, broken roller lifters are most often caused by weak or broken valve springs, or, valve springs that aren't setup properly, ie, not enough spring pressure! And if you're going to valve lift up in the .750 range, spring pressures are even more important!! My spring pressures are around 810lbs on the nose of the cam @ .080 from coil bind.

Also FYI, last lifter I had that broke also horked up the lifter bore at the bottom, then dropped metal particles on the piston which embedded into the skirt then proceeded to hork up the cylinder wall too.


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 Post subject: Re: This year
 Post Posted: Sat Dec 22, 2012 2:08 pm 
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Joined: Sun Apr 23, 2006 5:41 am
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Location: Newville PA
Ken,

What type of springs are you runing? us7race has stainless steel valves that are heavier than titainium like you have on your intake valve. I have Ti on both intake and ex and run about the same spring pressure. Bob J


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 Post subject: Re: This year
 Post Posted: Sat Dec 22, 2012 3:22 pm 
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scoop wrote:
Ken,

What type of springs are you runing? us7race has stainless steel valves that are heavier than titainium like you have on your intake valve. I have Ti on both intake and ex and run about the same spring pressure. Bob J


Bob I'm running the Manley 221424 NexTek spring. When I freshened up the engine winter before last they were still checking good as new with over 320 passes on'em and they went back on at re-assembly.

Right now they've probably got close to 500 passes on'em and I'll check a couple this winter but I'm looking to run them at leat one more season.

Local guy with a similar engine put over 700 passes on a set that checked good when he threw them away.

A lot of this depends on the cam profile though and mine is relatively mild by choice. I'm likely giving up some power for longevity.


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 Post subject: Re: This year
 Post Posted: Sat Dec 22, 2012 4:08 pm 
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Posts: 213
Location: Letellier MB Canada
Just my experience with nextec. I broke two in my 468, 7.20 lift cam turning 7500. Both within 200 passes. I broke one in my new 520, 800 lift cam turning 7500rpm within 150 passes. Both engines the springs were installed .060 before coil bind. The 468 installed at 1.900 the 520 at 2.000. I'll never buy another nextec spring.

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 Post subject: Re: This year
 Post Posted: Sat Dec 22, 2012 4:35 pm 
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Joined: Wed Apr 19, 2006 8:20 pm
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Location: N.J.
jmech wrote:
Just my experience with nextec. I broke two in my 468, 7.20 lift cam turning 7500. Both within 200 passes. I broke one in my new 520, 800 lift cam turning 7500rpm within 150 passes. Both engines the springs were installed .060 before coil bind. The 468 installed at 1.900 the 520 at 2.000. I'll never buy another nextec spring.


Weak/thin push rods will also break springs...

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running E85
Best ET 8.07
Best MPH 170.71
Barry


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 Post subject: Re: This year
 Post Posted: Sun Dec 23, 2012 11:09 am 
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Joined: Wed Apr 19, 2006 6:43 am
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Location: Tell City, IN
Ken0069 wrote:
FYI, broken roller lifters are most often caused by weak or broken valve springs, or, valve springs that aren't setup properly, ie, not enough spring pressure! And if you're going to valve lift up in the .750 range, spring pressures are even more important!! My spring pressures are around 810lbs on the nose of the cam @ .080 from coil bind.

Also FYI, last lifter I had that broke also horked up the lifter bore at the bottom, then dropped metal particles on the piston which embedded into the skirt then proceeded to hork up the cylinder wall too.



I dropped off the engine heads down, unassembled. The springs I normally run have 265 on the seat and over 800 open. There was a little facial damage on the bottom on a few of the pistons from the lifter breaking. I dropped off a set of springs he is going to check them and see if they will work, he said I need at least 250 on the seat and 800 on the open would be fine.

_________________
6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


Top 
 Profile  
 
 Post subject: Re: This year
 Post Posted: Sun Dec 23, 2012 3:54 pm 
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Joined: Wed Apr 19, 2006 8:20 pm
Posts: 5852
Location: N.J.
us7race wrote:
Ken0069 wrote:
FYI, broken roller lifters are most often caused by weak or broken valve springs, or, valve springs that aren't setup properly, ie, not enough spring pressure! And if you're going to valve lift up in the .750 range, spring pressures are even more important!! My spring pressures are around 810lbs on the nose of the cam @ .080 from coil bind.

Also FYI, last lifter I had that broke also horked up the lifter bore at the bottom, then dropped metal particles on the piston which embedded into the skirt then proceeded to hork up the cylinder wall too.



I dropped off the engine heads down, unassembled. The springs I normally run have 265 on the seat and over 800 open. There was a little facial damage on the bottom on a few of the pistons from the lifter breaking. I dropped off a set of springs he is going to check them and see if they will work, he said I need at least 250 on the seat and 800 on the open would be fine.




At 800 lift and running 8000rpm IMO 250 on the seat is not enough....I have had issues there before and now running just over 300 on the seat and 825 on the seat and everything looks just fine and valve adjustment never moves...

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running E85
Best ET 8.07
Best MPH 170.71
Barry


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