Solid roller lifters...

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Ok so after installing the lifters I see 5psi oil pressure drop in park and in gear idling. Driving there is zero difference in oil pressure. Overall there is still too much oil going up there with my .060” restrictor, top end is literally flooded.
I’m thinking to go with Indy recommendation about restrictor size.
Also I see that at full lift pushrod oiling hole is visible. My block does not have bushed lifter bores.
Cam has .462” lobes.
 
Cam is a bit different than initially planned, thanks to some insight from Jim Dowell. He made it for me in 2 weeks which is super fast these days.
For springs I used PAC-1225 which is the same thing as the Howard’s.
Overall I like it but I’m struggling a bit with idle tuning…





563CC62B-2A59-477E-884A-B5ADD9B242D9.jpeg
 
Well, it is a fairly good size cam all around. Also the LSA of 106 doesn’t really help. You’ll do just fine, I ask your time and drive it around as well. The plugs will tell you a lot.
 
Miszny said:
Cam is a bit different than initially planned, thanks to some insight from Jim Dowell. He made it for me in 2 weeks which is super fast these days.
For springs I used PAC-1225 which is the same thing as the Howard’s.
Overall I like it but I’m struggling a bit with idle tuning…





View attachment 1715964158
Click to expand...
That is a very health cam for the street. Not surprising you are having idle quality issues. Refresh my memory, Ayou or stick tranny? Which carb and intake?
 
Everyone has there own way of going about things......
And, if you’re having good luck doing something a certain way...... I’m all for continuing on with that process.

That being said....... I don’t like to use “tighter” lsa cams when the duration starts to get long...... and mufflers will be utilized.

The added overlap often results in more reversion at low engine speeds, which can be a challenge to tune for.

A quick test to see how much of an issue this might be is to remove the mufflers and see if the drivability improves.

Oh, and I spoke to Brad from BAM about the axle oiling.
As it turns out the oil holes just above the axles are the “auxiliary” oiling holes, and that there is a small hole edm’d from the cavity in the body to the area just above the wheel.
It’s there in the drawing I posted if you blow it way up and know to look for it.
 
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PRH said:
Everyone has there own way of going about things......
And, if you’re having good luck doing something a certain way...... I’m all for continuing on with that process.

That being said....... I don’t like to use “tighter” lsa cams when the duration starts to get long...... and mufflers will be utilized.

The added overlap often results in more reversion at low engine speeds, which can be a challenge to tune for.

A quick test to see how much of an issue this might be is to remove the mufflers and see if the drivability improves.

Oh, and I spoke to Brad from BAM about the axle oiling.
As it turns out the oil holes just above the axles are the “auxiliary” oiling holes, and that there is a small hole edm’d from the cavity in the body to the area just above the wheel.
It’s there in the drawing I posted if you blow it way up and know to look for it.
Click to expand...

Frankly the car drives better than I expected. My mufflers are basically straight perforated tube encased in box with some glass padding around the perforated tube. Not much restriction, after the muffler is just turn down before axle. I am using afr sensor as help with tuning and I had to change plenty to make it idle, IABs were 1st, I had to go with 56 from 62, MAB just 34 from 32. Primary jetting unchanged but needed to adjust throttle position on primaries and secondaries. With this amount of overlap it cheats the sensor so I need to check plugs also. Took me whole day and good amount of gas to be where I am with it now. Some finishing touches tomorrow.
Wot is what I like the most at this point :). This thing moves and revs very nice!

Thank you for the info on oiling, I think 5psi loss is acceptable, I can get it back with .045 restrictor to the heads I guess. I will give it a shot.
 
Glad to read things are rolling along well. Keep at it!
 
512Stroker said:
That is a very health cam for the street. Not surprising you are having idle quality issues. Refresh my memory, Ayou or stick tranny? Which carb and intake?
Click to expand...

Im running 727 manually shifted. Intake is Indy with port work and plenum mods, carb is 1050 dominator.
I’m not complaining about quality, it just took more than usual to make it idle well in park and in gear, but this thing barely pulls any vacuum so I guess I should have expected that…
 
rumblefish360 said:
Well, it is a fairly good size cam all around. Also the LSA of 106 doesn’t really help. You’ll do just fine, I ask your time and drive it around as well. The plugs will tell you a lot.
Click to expand...
I actually wanted it to be more obnoxious, since I needed a cam… actually wanted more duration with 108 also, but I don’t have enough static compression to work with. If this was 12:1 I would go all out.
One thing is certain, the car is much faster and utilizes that 5000 stall converter very well now.
 
Imo, with a cam like that....... there is too much “back flow” going on at idle for me to trust the O2 sensors to be accurate.
I’d just tune the idle so it “runs right”, and the O2 readings just are what they are.
 
Letting the plugs speak to you from there?
 
PRH said:
Imo, with a cam like that....... there is too much “back flow” going on at idle for me to trust the O2 sensors to be accurate.
I’d just tune the idle so it “runs right”, and the O2 readings just are what they are.
Click to expand...

That’s what I’m doing, I checked plugs many times today and have nice burn marks on my hands from headers as reminder ;-) It was a good day!
I need to get used to the car now.
My previous cam was 259/263@.050, 108 lsa with .450 lobes. Somehow with the new one it feels like big jump with power. It didn’t idle great either ;-)
 
It’s funny how the specs often don’t tell the whole story.
In the mid-90’s I ran an Ultra Dyne roller in my old 9.7:1 448 with ported 906’s.
.434 lobes, 259/264-108, in at 106.
It was much milder and better behaved than the RB SSH-44(old DC 510 hyd cam) it replaced.

A few years earlier I had run a RB STX-19 on a 105 in the same motor........ that thing had a very nasty and radical sound to it.
 
rumblefish360 said:
Letting the plugs speak to you from there?
Click to expand...
Yes, without checking plugs I wouldn’t know where I am. I still like to have o2 sensor and vacuum gauge. When things start to stabilize on both I see that the direction I’m at is the right one.
I ended up having 13.4-13.6 afr in park and 14.2-14.5 in gear. It was all over the place when I started jumping from 14.0 to 16+ in gear…
 
PRH said:
It’s funny how the specs often don’t tell the whole story.
In the mid-90’s I ran an Ultra Dyne roller in my old 9.7:1 448 with ported 906’s.
.434 lobes, 259/264-108, in at 106.
It was much milder and better behaved than the RB SSH-44(old DC 510 hyd cam) it replaced.

A few years earlier I had run a RB STX-19 on a 105 in the same motor........ that thing had a very nasty and radical sound to it.
Click to expand...
I really wanted a cam from RB :)
What is the spec on stx-19? There are 2 Stx-19M cams on the website.
 
Miszny said:
Yes, without checking plugs I wouldn’t know where I am. I still like to have o2 sensor and vacuum gauge. When things start to stabilize on both I see that the direction I’m at is the right one.
I ended up having 13.4-13.6 afr in park and 14.2-14.5 in gear. It was all over the place when I started jumping from 14.0 to 16+ in gear…
Click to expand...
Those afr numbers are very lean for gasoline
Can you post some closeup pic's of the plugs
What are you using for fuel?
 
512Stroker said:
Those afr numbers are very lean for gasoline
Can you post some closeup pic's of the plugs
What are you using for fuel?
Click to expand...

Will try to pull some plugs tomorrow to take photos. I’m running 100 octane pump gas. I imagine that with overlap this cam has these numbers are showing leaner than they really are.
 
As measured, my old STX-19 was 263@.050.

It was ground back in 1972 when RB was in California.
I got it at a garage sale, never run, in 1987 for $25.

I had done the break in with the headers open, and it really sounded bad ***!!
Then, I bolted up my 2.5” pipes with turbo muffs that went to the axle...... and it did not like that one bit.
It was running happy as a clam with the open headers.
With how the carb was adjusted like that......after the muffs were installed, when you let off the throttle it would die like you shut the key off.
I figured the distributor moved. Nope.
I checked everything...... had to mess with the carb more to get it to idle with the muffs.
Took it for a ride, and it was kind of a pooch.
I messed with it for a while, and this was back when I drove it on the street quite a bit........ but I wasn’t happy with it.
I took it to the track once...... took the muffs off...... totally different car.
Ran great like that.

I called RB the next monday(still out in Ca), I told him it didn’t seem to run good with the exhaust on it.
He chuckled and told me........ no, it’s not going to be happy with mufflers.

That was the beginning of my camshaft education.
 
PRH said:
As measured, my old STX-19 was 263@.050.

It was ground back in 1972 when RB was in California.
I got it at a garage sale, never run, in 1987 for $25.

I had done the break in with the headers open, and it really sounded bad ***!!
Then, I bolted up my 2.5” pipes with turbo muffs that went to the axle...... and it did not like that one bit.
It was running happy as a clam with the open headers.
With how the carb was adjusted like that......after the muffs were installed, when you let off the throttle it would die like you shut the key off.
I figured the distributor moved. Nope.
I checked everything...... had to mess with the carb more to get it to idle with the muffs.
Took it for a ride, and it was kind of a pooch.
I messed with it for a while, and this was back when I drove it on the street quite a bit........ but I wasn’t happy with it.
I took it to the track once...... took the muffs off...... totally different car.
Ran great like that.

I called RB the next monday(still out in Ca), I told him it didn’t seem to run good with the exhaust on it.
He chuckled and told me........ no, it’s not going to be happy with mufflers.

That was the beginning of my camshaft education.
Click to expand...
My headers go into 3.5” collector and it’s like that to the axle. I’m thinking this helps a lot, but my neighbors are not big fans…
On the other hand I switched from 3” to 3.5” and it didn’t seem to get louder.
I will see what I can get out of this :)

Also I need to test it on open headers now I guess ;-)
 
512Stroker said:
That plug is lean
Heat range looks good
Looks like the timing may be a bit retarded.
This should help ya figure it out
FBO Ignition - Home of the HRR688 - Spark Plug Reading
Click to expand...

Timing is now at 34, this is better visible on the back of the strap. I didn’t check my timing initially, I was sure it’s where it was with crank trigger but it was 26 degrees. It gave me headache at the beginning. It really didn’t want to idle like that too much. This is not final photo, I had my 5 year old son with me and couldn’t focus on documentation of the whole process too much. When he heard me start the car, it was impossible to make him stay home.
 
PRH said:
Oh, and I spoke to Brad from BAM about the axle oiling.
As it turns out the oil holes just above the axles are the “auxiliary” oiling holes, and that there is a small hole edm’d from the cavity in the body to the area just above the wheel.
It’s there in the drawing I posted if you blow it way up and know to look for it.
Click to expand...
That looks like one EDM hole on one side coming down..And yeah, overlap can cause issues with idle AFR readings.
 
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