My old school 340 upgrades and results.

[rumblefish360]

You wanted to know about how to measure at the rocker and find out your lift. Your worried about lift. You mentioned not getting the full amount and mentioned the deflection loss.

To get what your missing, the full 1.5 ratio amount, you need a good rocker, just one & a solid lifter with the correct length pushrod. Put the dial indicator on the valve too and measure up.

A .508 lift cam is a low lift cam and there should not be a clearance issue with stock valve train or piston, aftermarket or not. If there is, I would check how the cam is installed.
Using a better rocker for the full lift of the cam installed as so to get what you paid for is something everybody I would think everybody wants.

Do the math of the rocker ratios on your valve lift. Be aware that some of the OE stamped rockers can come in under 1.4.

 

[gtsdude]

I would run the hughs and shim them up

P5249847 for the 508/292
Single with damper
OD 1.50
Wire Diameter .207
103lbs @ 1.67
260lbs @ 1.27
Install at 1.67 to 1.68


HUG 1110
VALVE SPRING SINGLE W/ DAMPER
120# @ 1.660" INSTALLED 310# @ .550" LIFT
$7.00

• Installed Height/Pressure: 1.660"--120#

• Pressure @ .450" lift: 280#

• Pressure @ .500" lift: 300#

• Pressure @ .550" lift: 310#

• Coil Bind: .620" lift

• Outer Spring ID/OD: 1.033"/1.440"

• Type of Single w/ damper

 

[340dartley]

You wanted to know about how to measure at the rocker and find out your lift. Your worried about lift. You mentioned not getting the full amount and mentioned the deflection loss.

To get what your missing, the full 1.5 ratio amount, you need a good rocker, just one & a solid lifter with the correct length pushrod. Put the dial indicator on the valve too and measure up.

A .508 lift cam is a low lift cam and there should not be a clearance issue with stock valve train or piston, aftermarket or not. If there is, I would check how the cam is installed.
Using a better rocker for the full lift of the cam installed as so to get what you paid for is something everybody I would think everybody wants.

Do the math of the rocker ratios on your valve lift. Be aware that some of the OE stamped rockers can come in under 1.4.

I agree with everything you are saying . My questioning my lift and rocker ratio was more directed at This time with the spring coil bind and weather I need tof take it bakerhughes apart and send them back or go with what I have for now.

 

[j par]

.080 I think should be minimum bind. As mentioned that's a smallish Cam for what you're doing. I would think leaving much more room for a bigger cam and or higher ratio rockers. Not trying to cut it so close. Really everything seems to be happening very quickly and I can applaud that because I'm not one to let grass grow that's for sure, but it may be time to take a breath and make sure everything's being done the way you want it and not just being done to make it run. One thing I get problems with is all the suggestions not having time to soak in and too many things Bouncing Off My Brain and not taking a little time to store all those thoughts out. Just like you were saying that you looked at so many Springs they all started to melt together in the same respect to many suggestions start melting together and you not able to make the best decision. I know it's hard to slow it down when you want to get it done and sometimes that can be the hard part. I can't think of anybody here that's not in your corner though and wanting the best.

 

[gtsdude]

Comp cams 901 are also very close
Single Outer Valve Springs

• Rate: 387 lbs

• 1.080'' ID, 1.494'' OD

• Seat Load: 104 lbs at 1.650''

• Open Load: 259 lbs at 1.250''

• Coil Bind Height: 1.100''

• With Damper

 

[j par]

I've done the "for now" and just end up paying twice , way to many times!

I agree with everything you are saying . My questioning my lift and rocker ratio was more directed at This time with the spring coil bind and weather I need tof take it bakerhughes apart and send them back or go with what I have for now.

Iv

 

[rumblefish360]

Pardon pardon pardon

You should have no issue with coil bind or clearance at the retainer. The cam is a low lift.

 

[gtsdude]

Not sure what locks you have, but there are some available to add .050 to installed height

 

[340dartley]

I've done the "for now" and just end up paying twice , way to many times!
Iv

I know what you mean. I figure if all of my current rockers iron 273 or stock stamped steel work out to a ratio that gives me adequate clearance then I will go with what I have. Only will need to replace the springs at a later date if I change to a roller rocker with a true 1.5 ratio.

 

[j par]

I know what you mean. I figure if all of my current rockers iron 273 or stock stamped steel work out to a ratio that gives me adequate clearance then I will go with what I have. Only will need to replace the springs at a later date if I change to a roller rocker with a true 1.5 ratio.

Or like I just did a true 1.6 ratio

 

[340dartley]

Or like I just did a true 1.6 ratio

That would be great but I am money challenged at the moment. I know those words don't work with race car or engines lol

 

[j par]

LOL you're preaching to the choir literally it took me 2 years to get to those 1.6 rockers. I still have my 273 rockers sitting on a shelf waiting for my next build. But, when I was able to actually afford them I had the room to just drop them on.

 

[gtsdude]

what are the specs on the springs you have? Is the reduced installed height going to be too much seat and open pressure for that cam? Hate to wipe a lobe

 

[340dartley]

what are the specs on the springs you have? Is the reduced installed height going to be too much seat and open pressure for that cam? Hate to wipe a lobe

I talked to comp cams as that is who the mopar performance tech guy said manufactures the purple cams now for mopar. Mine is old enough it was probably made by racer brown. Anyway they seemed to think 350 psi seat pressure would be good for the rpm I wanted . Aka 6500. The springs I have spec at 318 psi at 1.3. I am compressing them to 1.2 Ish . I would imagine they would be in 350 to 360 range. I may grab one and take down to a machine shop to see what it measures at that height.

 

[Marcohotrod]

on a budget and not racing for the world championship stock rockers are fine. with the pushrod angle and slightly less than 1.5 ratio your new springs will be fine. if you go to a shop to measure bring a couple of new ones and a couple of the good used ones and installed heights. to measure lift at the valve u need a solid lifter, or a hydraulic lifter modified to solid, or a very light spring with a hydraulic lifter

 

[rumblefish360]

Comp is grinding for MP now?
Is this what I just read?

 

[340dartley]

Comp is grinding for MP now?
Is this what I just read?

That is what the Mopar Performance tech guy said. Don't know how reliable his info is.

 

[340dartley]

Just talked to my local machine shop engine parts supplier. Not so much related to what I am putting on but what I am taking off. I figured it would be nice to have a good set of performance valve springs on the shelf and they said they can supply me with inner springs by themselves. I am going to take the inner springs in and a complete dual valve spring so they can match and replace the broken springs and we can match the spring tension. While taking it apart I think the inner springs failed due to coil bind. When trying to compress them to get the keepers off I run into coil bind before I can completely clear the keepers. To use them I will have to machine either the head or retainers or both

 

[340dartley]

Didn't do a whole bunch on the car tonight. Getting close to 100 outside and more in the garage. I did try a couple of different spring compressors. I have a snap on one designed for a Chevy that pivots off of the stud that worked really well. I put a bolt in the shaft tower and rolled it pulled it at a 45 degree angle from the head over the valve. Changed out a double spring in a couple minutes. Much better than last night. I also took the opportunity to measure coil bind of the old springs. Installed height was 1.73. Coil bind on the outer spring was 1.05 and inner spring was .900. The inner spring sits on a raised shelf on both the retainer and cylinder head. It's installed height is 1.513. Tomorrow I will take them down and have the pressures checked and hopefully get a couple new inner springs.

 

[j par]

I agree with post 168. Going to the machine shop and getting some good advice. For some of us and I'm talking to myself there's a lot of things I can do but there are things that should be taken to the professionals. Or at least discuss.

 

[340dartley]

Last night I sat in the living room with the family trying to get my dial indicator mount to work. It is one of those metal cable with the snake that tightens and locks with a lever. Messed with it for about an hour before I decided it is now junk. The cable pulled out of one of the ends. Might go to the hardware store to see if I can get the stuff to remake the cable.
The tool that seemed to work well last night when compressing valve springs is this one by snap on. Probably could make it cheep enough though.

 

[340dartley]

On another note my plan of action is always changing. I will be taking the heads off in the near future. Once I am sure the springs are not going to bottom out and destroy stuff I am going to fire the engine and test for the pop. After that plan to get to the track so I can get some baseline numbers. When pressuring the cylinder with air last night I noticed a little more air leaking out the exhaust than I am comfortable. It had even compression before all this but it could probably use a valve job. May take the opportunity to rering the motor if I think it will help anything. Will check cylinder wear at that point. I was digging through my junk and found a pair of head gaskets still in the package so should still be on a budget. When I am going back together with all this is plan to swap intakes. Then take it back out to the track.

 

[70aarcuda]

I bought this one from Ed Hamburgers For 340 only back in the 80s...it would be easy to copy...works great two flat pieces of steel with holes for shaft and bolts onto head.....the apparatus for the springs is curved...bad picture here...i modified it years ago to allow to get to springs with car with the engine set back...

I have a piece of pipe that fits over short shaft to compress springs...can do springs on heads in minutes..

just add an air chuck for the cylinder...

 

[340dartley]

Just picked up a dial indicator magnetic base from harbor freight. I hate going there but the matco dial.indicator indicator snake is junk don't buy one. Only way to get the matco one is to buy another dial indicator.

 

[yellow rose]

I talked to comp cams as that is who the mopar performance tech guy said manufactures the purple cams now for mopar. Mine is old enough it was probably made by racer brown. Anyway they seemed to think 350 psi seat pressure would be good for the rpm I wanted . Aka 6500. The springs I have spec at 318 psi at 1.3. I am compressing them to 1.2 Ish . I would imagine they would be in 350 to 360 range. I may grab one and take down to a machine shop to see what it measures at that height.

I think you mean 350 OPEN pressure and that is too much for a stock rocker. 350 on the seat is big time roller crap.

As rumble said, you are overthinking this deal by a long way.