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Need some engine advice

Did I misread or are the replacement rockers the same as what was on there when all the trouble started? No HS right?
 
Runcharger said:
Did I misread or are the replacement rockers the same as what was on there when all the trouble started? No HS right?
Click to expand...
The replacement rockers are PRW 1.6 stainless. I was given the choice of any rocker up to the cost of HS's. Went with the PRW's after talking to a few people for their opinions. Mike at B3 racing probably influenced that decision the most. He said they are by far the best as far as sweep pattern with Trick Flow heads. He also thinks that steel is far superior to aluminum. He uses the PRW's almost exclusively when going 1.6 ratio.
 
hunt2elk said:
The replacement rockers are PRW 1.6 stainless. I was given the choice of any rocker up to the cost of HS's. Went with the PRW's after talking to a few people for their opinions. Mike at B3 racing probably influenced that decision the most. He said they are by far the best as far as sweep pattern with Trick Flow heads. He also thinks that steel is far superior to aluminum. He uses the PRW's almost exclusively when going 1.6 ratio.
Click to expand...
You may have misunderstood what I was saying about the PRW rockers. Yes, I use a lot of them on street builds, because steel has a much longer fatigue life than aluminum if you want to put considerable miles on the car. I would rather avoid the roller bearings as well if they aren't needed. But, the PRW rockers will not have the best sweep pattern with Trick Flow heads, unless the shaft is properly located. Any rocker can have that good of a valve tip sweep pattern when the shaft is at the right place. Some are just easier to get there than others.

The PRW advantage is having multiple ratios available and using a cup style lash adjuster. Every off the shelf single shaft Mopar rocker has an adjuster that is too low and on the wrong angle, which causes excessive angularity and sweep, especially those with a ball style adjuster. With the cup adjuster, you can run the adjuster higher and reduce some of the sweep. The additional support from the rocker body, when the adjuster is higher, will also reduce the chance of adjuster failure from side loading due to the excessive angularity. There are better (custom) rockers available, but they naturally cost more.
 
PRHeads said:
It’s been many years since I looked into the plenum of a low deck Holley SD........ but I don’t remember it having the “dams” on those 3 runners.
I wonder if they all/always had that?
Click to expand...
Mine had them, but I mostly took them out. I hope it works better than the ported Streetmaster it is replacing.
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B3RE said:
You may have misunderstood what I was saying about the PRW rockers. Yes, I use a lot of them on street builds, because steel has a much longer fatigue life than aluminum if you want to put considerable miles on the car. I would rather avoid the roller bearings as well if they aren't needed. But, the PRW rockers will not have the best sweep pattern with Trick Flow heads, unless the shaft is properly located. Any rocker can have that good of a valve tip sweep pattern when the shaft is at the right place. Some are just easier to get there than others.

The PRW advantage is having multiple ratios available and using a cup style lash adjuster. Every off the shelf single shaft Mopar rocker has an adjuster that is too low and on the wrong angle, which causes excessive angularity and sweep, especially those with a ball style adjuster. With the cup adjuster, you can run the adjuster higher and reduce some of the sweep. The additional support from the rocker body, when the adjuster is higher, will also reduce the chance of adjuster failure from side loading due to the excessive angularity. There are better (custom) rockers available, but they naturally cost more.
Click to expand...
I definitely may have misunderstand what you said, had a lot going on with this motor last fall, and wanted to get it back together before the snow flew. It actually may have been Brian that said the PRW's have a decent sweep on the Trick Flow's. I remember you saying that you prefer Comp steel rockers, but they are only made in a 1.5 ratio, so you use a lot of the PRW 1.6's when wanting that ratio, and have had good luck with them. Regardless, I am leaning towards a cam swap in this motor. When that happens, I will have more time and will be contacting you for your relocation kit....
 
hunt2elk said:
Nice. Looks like you welded up the spreadbore opening as well?
Click to expand...
Mine was actually a square bore manifold I picked up many years ago at a swap meet. I have a pic of it on my old computer prior to porting. The ports were tiny.
 
Update on this thread as I have finally been able to get some miles on it. I have done 3 things to the motor.
First, swapped the Weiand Action + intake for a Holley Street Dominator.

Second, when Brian ordered the pushrods last fall, he had them made a bit long. I had 3 that I could get a proper preload set, but the other 13, I had to guess by going off physical measurements. He sent me 9.225", so I ordered another full set at 9.185" and then swapped in 13 new ones. Now I have fairly similar threads turned in on all 16. I have no idea why there is such a variation, maybe the cam is f'ed up, idk. Tips of the valve stems are all level.

And third. He pretty much made me buy a MSD ready to run distributor from him when he built the motor. I absolutely hate that thing and would never buy another. Such a pain to adjust the mechanical advance, and then you are limited to the bushing degrees. I had to buy a special 14 degree bushing to get where I wanted to be. Also, they come with a non adjustable vacuum advance can, which is just ridiculous in my mind. Got ahold of Holley and was told they make an adjustable unit for GM that will work on this distributor. Ordered 3 of them before getting 1 that worked. I also changed the springs to bring in my advance at 2100 rpm instead of the 2900 it was before. I had to have it that slow previously because of the non adj. vac can was adding way to much and causing detonation.

So timing is now set at 20 initial, 34 total, and 42 all in with the advance hooked to ported vac.

These changes made a noticeable improvement in power. I really like the SD intake. I read articles stating you should never run a single plane on a street car, but this is nice throughout the rpm range. No issues at all at lower rpm's. I believe if I had 3.91's or so in the rearend, this thing would really rock. With the 3.23's in it now, 55mph = 2200rpm, 60mph = 2400rpm, and 70mph = 2800rpm. Really nice on the freeway, but of course I am giving up takeoff power. It will now break the tires loose in 1st as well as 2nd gear. If I do anything else now, it may be to go to 3.54's. If the cam is going to hell, I will start over with the motor and have a correct quench and different cam with a 108 lsa built.
 
Glad to hear of the improvements. I use the MSD Pro-billet on most strokers, unless it’s a true road car and needs vacuum adv. the MP units have been fine for that. I used an RTR distributor once. Not a fan. Change those gears, your inner child will thank you!
 
Yes change the gears I know I want to change mine. Love the 323 for cruising but miss the 354.
 
3.54:1 Dana 60 and 0.68:1 overdrive with the SS-700 5-speed is like a 2.41:1 final gear ratio. Runs nice behind the 505" stroker.
Currently putting 3.55:1 in an 8-3/4" with a 518 0.69 overdrive is like a 2.45:1 final gear ratio. That is going to be behind a 360" small block.
I considered using the 3.23:1 gears, but final ratio is about 2.23:1, and my 518 is a non-lockup unit, so 70 MPH would be about 2,000 RPM, where the 3.55"1 gears in OD would be about 2,200 RPM with a tires about 26" tall.
 
needing more than 3.23 gears with 493 cubic inches that should make at least 500-525 pounds foot of torque for a street car, makes no sense to me.
 
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