Valvetrain + eddy heads ?

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Mattmoto441

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So I just got the 340 dropped into the car last weekend and I'm running eddy 60179 heads on the stock valvetrain (rockers and rods ) but I'm beginning to believe that I need some different length pushrod? Car runs great but have a lil chatter in the rockers . Haven't torn it apart to verify but that what it sounds like .
Cam specs are Comp cam
Intake Duration at 050 inch Lift:240
Exhaust Duration at 050 inch Lift:246
Duration at 050 inch Lift:240 int./246 exh.
Advertised Intake Duration:284
Advertised Exhaust Duration:296
Advertised Duration:284 int./296 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.507 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.510 in.
Valve Lift with Factory Rocker Arm Ratio:0.507 int./0.510 exh.
Lobe Separation (degrees):110
 
Sounds like you could use some additional pre load on those lifters. That's why I put adjustable rollers on mine with the Edelbrock heads. 65'
 
What does the rocker arm on the tip of the valve look like !! The tip should be in the middle of the valve !! If the rocker arm is hitting on the outside of the valve , the pushrod is to long ! If it’s hitting on the inside of the Valve you need longer pushrods !
 
Probably 2 things are wrong. Push rod length and valve train geometry. Cylinder heads new add on?
Better call Mike at B 3 Racing.
 
Should never put on stock non adjustable rockers on any aftermarket heads. Too many small variables will lead to too much or not enough adjustment.
1. Get adjustable rockers Harland, t&d, jesel, comp, speedmaster steel, prw ect.
2. Call Mike at B3 about geometry and buy one of his kits. Dude has a lot of knowledge on why the geometry is off.
3. Be happy knowing you did things right
 
As mentioned above, contact Mike with B3. He knows his stuff & will not try to get over on you.
 
Recheck the lifter preload.
If it’s currently in the .030-.080 range, I think you’re going to discover that the Comp XE cams can tend to be noisy.

Some brands of lifters tend to be noisier than others as well.
 
Mike at B3 Racing can set you up with all of this. Cut the variables out and stay with one source. Mike is very good at this and will not steer you wrong.
 
Mattmoto441 said:
So I just got the 340 dropped into the car last weekend and I'm running eddy 60179 heads on the stock valvetrain (rockers and rods ) but I'm beginning to believe that I need some different length pushrod? Car runs great but have a lil chatter in the rockers . Haven't torn it apart to verify but that what it sounds like .
Cam specs are Comp cam
Intake Duration at 050 inch Lift:240
Exhaust Duration at 050 inch Lift:246
Duration at 050 inch Lift:240 int./246 exh.
Advertised Intake Duration:284
Advertised Exhaust Duration:296
Advertised Duration:284 int./296 exh.
Intake Valve Lift with Factory Rocker Arm Ratio:0.507 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio:0.510 in.
Valve Lift with Factory Rocker Arm Ratio:0.507 int./0.510 exh.
Lobe Separation (degrees):110
Click to expand...

PRH said:
Recheck the lifter preload.
If it’s currently in the .030-.080 range, I think you’re going to discover that the Comp XE cams can tend to be noisy.

Some brands of lifters tend to be noisier than others as well.
Click to expand...
For the moment, skip all the other replies. Let’s focus in on the Comp Cam and it’s lifters. The cam has an aggressive duration and the lifters are taxed at the rate of lift that what your probably hearing is a normal thing. The pushrods should be depressing the lifters to the Comp Cam spec. (which I read a few days ago and can’t remember damm it!) Failure to have the pushrod depress the lifter enough or to much will cause a loud valve train by itself.

The factory rockers are know to be less than there advertised 1.5 ratio. There fine for use on a low lift cam such as yours.

Your saying “Why? It’s a .500+ lift!“

Not exactly..... the lift given on the cam cars is the Theoretical lift given at a 1.5 rocker ratio which doesn’t account for the valve trains oddities of the lifter angle and pushrods angles and lastly, as mentioned, less than a 1.5 rocker ratio that is normally found on the stock stamped rockers.

Now, back to what everyone else was saying...
The best fix is a geometry correction that starts with a call to Mike @ B3 Racing & ask him for his recommend rocker that he likes. Since you probably do not have roller rockers, ask Mike what he likes. Now between the two, geometry corrections and new and true 1.5 ratio rockers, not only will you have a quieter valve train but a corrected one that will be worth the price of it all in gaining back the lost power you intended the engine to have.
It is also IMO that you move to a 1.6 rocker for two reasons. First, it will add a minor boost in intensity to the cam. Second, the more lift you have with the better Edelbrock heads the better since the best flowing part is when the valve gets lifted higher.

I just got done with a 340 that is (temporarily) using the OE rockers on the XE285HL cam w/as heads (same as yours) and it runs just fine. However! Down the road I will have just what I suggested. FOR SURE!

Make good use of the head and lift that freakin valve up high to take advantage of the heads air flowing abilities. Otherwise, you could have given your stock iron heads a good valve job and a bowl porting and ended up at the same place. Just with more money in your pocket.

BTDT... always afford the best head you can and then take advantage of all it has to offer!

264AED17-A539-44E2-A74A-63EDF0806451.jpeg
 
rumblefish360 said:
For the moment, skip all the other replies. Let’s focus in on the Comp Cam and it’s lifters. The cam has an aggressive duration and the lifters are taxed at the rate of lift that what your probably hearing is a normal thing. The pushrods should be depressing the lifters to the Comp Cam spec. (which I read a few days ago and can’t remember damm it!) Failure to have the pushrod depress the lifter enough or to much will cause a loud valve train by itself.

The factory rockers are know to be less than there advertised 1.5 ratio. There fine for use on a low lift cam such as yours.

Your saying “Why? It’s a .500+ lift!“

Not exactly..... the lift given on the cam cars is the Theoretical lift given at a 1.5 rocker ratio which doesn’t account for the valve trains oddities of the lifter angle and pushrods angles and lastly, as mentioned, less than a 1.5 rocker ratio that is normally found on the stock stamped rockers.

Now, back to what everyone else was saying...
The best fix is a geometry correction that starts with a call to Mike @ B3 Racing & ask him for his recommend rocker that he likes. Since you probably do not have roller rockers, ask Mike what he likes. Now between the two, geometry corrections and new and true 1.5 ratio rockers, not only will you have a quieter valve train but a corrected one that will be worth the price of it all in gaining back the lost power you intended the engine to have.
It is also IMO that you move to a 1.6 rocker for two reasons. First, it will add a minor boost in intensity to the cam. Second, the more lift you have with the better Edelbrock heads the better since the best flowing part is when the valve gets lifted higher.

I just got done with a 340 that is (temporarily) using the OE rockers on the XE285HL cam w/as heads (same as yours) and it runs just fine. However! Down the road I will have just what I suggested. FOR SURE!

Make good use of the head and lift that freakin valve up high to take advantage of the heads air flowing abilities. Otherwise, you could have given your stock iron heads a good valve job and a bowl porting and ended up at the same place. Just with more money in your pocket.

BTDT... always afford the best head you can and then take advantage of all it has to offer!

View attachment 1715563519
Click to expand...


Lol dang I like simple answers haha

I orginally ordered a lunati cam and lifter but the cam was back ordered for months so I went with the comp .on the lunati lifters
 
Agree with Rumble , adding adjustable 1.6 rockers sure helped my 340 picked up 10-20 hp peak hp moved from 5600rpm to 6200 rpm
 
Nat said:
Agree with Rumble , adding adjustable 1.6 rockers sure helped my 340 picked up 10-20 hp peak hp moved from 5600rpm to 6200 rpm
Click to expand...
Thanks man and (OP) now you know I wasn’t kidding. practically free HP with added rpm.

Let it breath deep my friends.... breath deep...

I should do videos in my retirement.....
This would be an awesome one.
 
rumblefish360 said:
Thanks man and (OP) now you know I wasn’t kidding. practically free HP with added rpm.

Let it breath deep my friends.... breath deep...

I should do videos in my retirement.....
This would be an awesome one.
Click to expand...
Ok what's a good 1.6 rocker set ? Not looking to spend a ton but if I gotta get a new set anyways . Also will this effect the driveability of the car ?
 
It will not effect drivability. I don’t know how you would think that but fair enough...

Ive tried several brands without any issue worth longing in however, since I told you to contact
Mike @B3 Racing............
 
rumblefish360 said:
It will not effect drivability. I don’t know how you would think that but fair enough...

Ive tried several brands without any issue worth longing in however, since I told you to contact
Mike @B3 Racing............
Click to expand...
Dont the 1.6 rocker add lift and duration? Making it seem like it's a bigger cam .
 
My experience is that swapping from 1.5 to 1.6 rockers on the dyno has the motor sound like the cam is bigger.
It’s instanly noticeable.

My one “however” is...... I have never done that rocker test on anything that had a cam so small that it wasn’t kinda lopey already.

Power wise?
For the stuff I’ve tested, the gains are usually quite small.
The instances where the gains were fairly noticeable were combos that were designed to run the higher ratio from the beginning.

I would say at least 50% of the tests I’ve done ended up with no worthwhile gains..... or losses.

The trend for me has been, if the cam is kind of “too small” for the combo, you’ll see a gain.
If the cam is big enough, and fast enough...... gains will be minimal...... or it can actually show less power with the higher RR.

An example of the “no gain” is when AndyF tried 4 different ratios on one of the 470’s with TF heads.
1.5, 1.6, 1.65, 1.7....... all made the same power.
 
Now that AndyF write was really good testing all of those rockers. Considering everything he was doing, the thought out combo, it was an above and beyond test and effort. I loved the article. It was very telling about the cam size and how well it was for the combo and the changes in power he found. Very interesting stuff which you would have to think about how it “May Apply, or Not” to your combo. As nothing is an absolute Guarantee on how it reacts. Not unless you mimic the combo or build something extremely close.

If there is anything that like to do is take advantage of the available head flow as much as possible. It doesn’t always have to be a crazy high lifting cam taking down 100% of the heads ability.
 
interesting stuff which you would have to think about how it “May Apply, or Not” to your combo.
Click to expand...

And that can be applied to just about any aspect of engine building.
 
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