[Gach]

To make it simple for you to understand ( and I know thats going to be hard for you ) it was the wrong rod for his Application he should’ve used his power adder rod.

[Gach]

When Tom told me that the Pontiac rods list are NOT! Power adder rods. That explains everything.

[Stan Weiss]

Originally Posted by Gach

This is little confusing I just talked to him wanted get it from houses mouth. The Pontiac rod is NOT ! Power adder rod. That’s exactly what he told me. For $747.00. One would have to go BBC rod which is 6635. vs Pontiac which is 6625. All their rods small end are bushed, for 990 pin. The BBC power adder rod is $868.00 bucks. The one that’s $1118.00 is super power adder rod for boost motors.

So now the motor I’m putting together for a customer/friend the pistons have .9270 pin, which would require them to change the bushin, to fit .9270 pin, that’s an additional $200.00 so now your talking 1068.00 to get their power adder rod, but here’s the problem that rod is .010 longer then Pontiac rod, meaning the piston will be sticking out of the hole. .010. the block has already been squared and Sonic tested. I would never cut the tops of a piston to make up the .010 longer rod.
__________________

What problems does the piston 0.010" out of hole cause? I have never done it, but back in the day had a friend that ran (SBC) the piston 0.005" out of the hole and it ran great.

Stan

[Gach]

What we all know, depending on rod your running, let’s say steel rod, that requires minimum of .30 piston to head. And your trying to get compression up there. Now you would have go for .40 head gasket. I can’t remember what thickness they come in off top of my head . Before you have go to custom head gasket I mean it’s definitely doable. I’ve run them .08 out of the hole with no problem. saying you have account for that. Then again depending on the top ring location for good ring seal. The pistons I used at the time had top ring set up for nitrous which is set lower from top then standard piston ring set up. So if the block be squared and decked. That .010 could effect ring seal. Just have to take all that into account.

[Gach]

One quick example a friend put his together and guess what pistons from corner to corner where sticking out .017 I mean who knows what issues caused that. They ended up cutting tops of the piston and screwed them up, ended up buying 4 new custom pistons.

[PAUL K]

One could just use a slightly thicker head gasket.

[b-man]

Built my 421 trying for zero deck and the custom dished Ross pistons still ended up .007”-.008” above the deck despite our best efforts at calculating the compression height we needed.

Ended up using .045” Butler composition gaskets so everything worked out fine. The gasket thickness as well as the gasket bore diameter matched up nicely with the 4.135” pistons.

The rods I used were a set of I-beam Crowerods I purchased for nearly $900 back in 1993 for a 455 HO build. In those days your only other forged rod choices were 455 SD and Bill Miller aluminum. Seeing Molnar forged steel rods selling in the $750 range looks pretty good I’d say.

[Gach]

Yep simple solution.

[Gach]

For a while quench area, thought to be a issue, because I run aluminum rod I’m at .060 piston to head. .010 in hole with .050 head gasket. No problem. I think though if you went with .010 longer rod and ended up .020 out might be a problem I think that would be very rare. But you never know what your handed at times.

[Gach]

Originally Posted by b-man

Built my 421 trying for zero deck and the custom dished Ross pistons still ended up .007”-.008” above the deck despite our best efforts at calculating the compression height we needed.

Ended up using .045” Butler composition gaskets so everything worked out fine. The gasket thickness as well as the gasket bore diameter matched up nicely with the 4.135” pistons.

The rods I used were a set of I-beam Crowerods I purchased for nearly $900 back in 1993 for a 455 HO build. In those days your only other forged rod choices were 455 SD and Bill Miller aluminum. Seeing Molnar forged steel rods selling in the $750 range looks pretty good I’d say.

Definitely have come along way since then. It definitely hurt the pocketbook to dig out for them Crower rods

[Tom Vaught]

Originally Posted by b-man

The rods I used were a set of I-beam Crowerods I purchased for nearly $900 back in 1993 for a 455 HO build. In those days your only other forged rod choices were 455 SD and Bill Miller aluminum. Seeing Molnar forged steel rods selling in the $750 range looks pretty good I’d say.

INTERESTING. In 1993, I was testing 6 identical engines to failure.
The rods we used were Forged Steel Carrillo connection rods.

I went back and checked my notes and they were made in the 1993 time-frame for our test engines on the dyno. So maybe they were busy doing my stuff and the sales guy could not build a set of rods for your 455 HO engine build. Did you actually have contact with them Bart???

Tom V.

[b-man]

The Crower rods though very expensive were somewhat affordable. I was already breaking the bank so Carillo rods were pretty much out of the question at that time in my life so I didn’t inquire.

The power output of that 400 hp street 455 HO wasn’t anything to write home about but I was trying to build something solid. Factory cast rods were more than up to the task actually for what I was doing. I bought the Crower rods for insurance, that 455 was my first Pontiac engine and it had thrust issues due to questionable block/main cap machining so I took it apart.

I ended up enjoying bracket racing for a decade using another nice stock bottom end I found that included the original rods, pistons and bearings. So that’s why I had those old Crower rods laying around, they had the equivalent of maybe a couple hundred street miles on them before they eventually ended up in my 421 HO which also doesn’t need them really.

[tom s]

Crower Sportsman Pontiac rods are now $1360.FWI,Tom

[TransAm 474]

Just to add to the great info here on the Molnar rods .... here is a side by side comparison between an Eagle H-Beam rod(left) and a Molnar Power Adder rod(right). As you can see, the Molnar is substantially beefier.

EDIT:: Not sure why the photo is not showing up, but you can just click on the attachment ...

[misterp266]

Yes, it does look much beefier! Had to crop the photo to make it work.

[TransAm 474]

Originally Posted by misterp266

Yes, it does look much beefier! Had to crop the photo to make it work.

Awesome, Thank You!

[Half-Inch Stud]

Early 90's Carrillo rodset was $2,000 right? $2,300 these days for the top Carillo Pontiac offerings.

[Dragncar]

Here are some pics of Molnar 6.8 BBC rods so many of us run. Standard Molnar rod is on the left. Power Adder is on the right. (not a Power Adder+ rod)
Notice the weight on the PA rod is more concentrated in the middle. And the pin area is thicker. The PA rods do not look as wide, sideways as the standard rod.
Can not get anymore pics of the standard rod.
They are in my 461 with High Ports waiting to be fired up. Still have the PA rods in a box.

[Dragncar]

Originally Posted by Gach

That was part of my Conversation with Tom the other day and he explain why it happen, so why do you want to drag him though the mud.

Gach, this thread entirely exists because of the garbage, un truths and half truths going on on your site. I have not posted on there in a long time. But when I seen the thread and tried to make a post like my original post on my thread here defending Molnar, it disappeared. Imagine that.
The, only good enough for a resto rod, street cruiser , hop sing, tick, tick type stuff comes from PZ
So I set things straight here. Where you have no control.
It is you who have been dragging Molnar through the mud for years. I have been doing the exact opposite for years. Praising them. Telling all who would listen they are the best rod for the money, PERIOD.
Sure, Power Adder rods are not available for Pontiac. But that series of rod has never been broken, so what does it matter. Besides, all the big power guys run a BBC rod anyway and you can get those in PA and PA+.
So this "confusion" stuff was made up so you could have a angle.

These rods, any series have never been broken due to the rod snapping, big end going out of round seizing up . They have been found bent and ripped in half. BUT the pin was ripped out of the piston. Meaning it broke first. And the big end half was sill able to be spun freely on the crank. Meaning, it did its job. No Molnar rod has been found broken with piston still attached to the small end that I know of. Its almost too good to be true, but it is.
The job Tom Molnar has done is simply amazing.
Folks have made more power than their piston could take and the rod paid the price. (IE, use billet pistons on builds like that)
You looked at this thread for a few days and did not post. I think you are on this thread in some effort to save face. Because you have been proven wrong on Molnar rods.
If folks want to know what you really have said about Molnar all they have to do is go to PZ (if you can find it) and do a search for Molnar. Its all there.
Like this.
But I do not want this thread closed up for arguing like how you got my thread on a larger dia oil pump pickup tube thread closed that was so full of good info. Heck, and that was when we got along !
BTW, my post # 73 was done to show your post about agreeing that you have not heard a bad thing about Molnar rods was so not true.

[TransAm 474]

Thanks for posting the pictures, much appreciated! I hope this thread don't get closed either, lots of good info and pictures here for future users ....