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B engine rods

I can see why you getting frustrated...something is likely off in your compression numbers.
Using a 400s 9.98 deck height....the icons and 6.86 rods should be .007 below the deck. They are mid to high 8's w a 90 cc head and about 10.1 with a 74 cc head figuring with a .045 thick head gasket. If the piston were .18 shorter that is about 6:1 compression not 9.3.
My numbers are using summits compression calculater.
To accurately use the compression Calculater you need the head cc's and the head gasket thickness. I assume if your boosting your going to run cometic head gaskets? Imo..they are the only way to go.
 
Years ago I started collecting parts to do a stock stroke 400 using a 440 rod. The combo also gives you a better rod angle ratio....
 
I had a really nice set of aluminum hemi rods with only a few passes and was contemplating something similiar...400 with a turbo...but the rods found there way back into a 440.
 
If your building a turbo with any power shelf pistons aren't going to cut it. Weve been down this trail. Sagged the centers without ever hurting a ring land. I wouldnt run any without at least .250" piston head thickness. Along with the ring lands down and wide spaced .250". Wider rings transfer the heat better as well, 1/16" minumum. A custom piston with either a std journal B rod (1.094" or .990") or a 2.200/.990" RB rod should get it done. We run a stock block/cast crank 360. Been 9.55@142/ 3750lbs
Doug
 
Last edited:
I guess I missed it somewhere..... but what is it you are trying to do ? and what's the problem in a stock stroke 400 Engine as it relates to just using an H-Beam Rod with the 1.094" Pin ?
What's the problem ?
The Piston availability ?

For use with the Eagle H-Beam CRS6358C3D Rod ?
all we've ever done is just Call Diamond Pistons and tell them you need a 51903 Piston made for the larger 4.375" Bore (1.094" pin)
Depends who you talk to down there, but if they tell you it's a "custom" tell them to pound salt because they rarely have them on the shelf anyway so only build as ordered, and NO big deal to adjust the Bore Size ?
It's a 4032 Forging, but unless this is a high boost/blown application the 4032 alloys are fine ?
 
Sorry for the delay in replying, I have a second job to pay for my hobbies, lol. I will try to answer the questions posted.. Math is NOT my strong suit, I likely goofed something up big time.

One of the fellows coaching me along in this project found a post over on FABO, that claims the ICON IC825 will work in conjunction with the 440 rod, and will fall .045" in the hole, which I believe is about what a stock piston does. I will be running Cometic head gaskets, and I think .027" is about the thinnest offered. Heads I have a choice of, my original plan was to run a set of ported "516" castings that I have that have the 2.08/1.74" valves installed with a fair bit of porting done, (professionally), and a light cut to the deck. The second set is a set of "906" castings with the 2.14/1.81" valves, a light deck cut and pretty extensive porting. One of the fellows helping me strongly suggested the bigger heads, and I am fine with that, but the open chamber will kill some compression. I can CC the 906's as I can't recall what they were when done.

I would like to land somewhere in the 9's for compression, and a $500 set of ICONs and an Eagle 440 rod would make me very happy to find.

I really appreciate all your time, this is my first turbo project, and I am excited to keep it coming along. Thanks!
 
Challenger340 said:
I guess I missed it somewhere..... but what is it you are trying to do ? and what's the problem in a stock stroke 400 Engine as it relates to just using an H-Beam Rod with the 1.094" Pin ?
What's the problem ?
The Piston availability ?

For use with the Eagle H-Beam CRS6358C3D Rod ?
all we've ever done is just Call Diamond Pistons and tell them you need a 51903 Piston made for the larger 4.375" Bore (1.094" pin)
Depends who you talk to down there, but if they tell you it's a "custom" tell them to pound salt because they rarely have them on the shelf anyway so only build as ordered, and NO big deal to adjust the Bore Size ?
It's a 4032 Forging, but unless this is a high boost/blown application the 4032 alloys are fine ?
Click to expand...

It is a turbo build, but not a super wild one, and there is a budget, sort of. A $500 set of ICONs fits nicely, if such an item exists.

I will keep boost as low as I can to meet my goal, up to 15 Psi max. One of the fellows helping me thinks I will hit my number well below that, I hope he is right. The blocks are really the limiting factor, so I can only push it just so much anyways.
 
What is your goal? Thin pistons will only cost you more when they fail. I'd run the stock rods with new bolts and spend the money on pistons if you're short on cash. You wont need over 6000 rpm.
Doug
 
dvw said:
What is your goal? Thin pistons will only cost you more when they fail. I'd run the stock rods with new bolts and spend the money on pistons if you're short on cash. You wont need over 6000 rpm.
Doug
Click to expand...


750 is the goal, and I was thinking 5,500-6,000 should be plenty of rpms to get there.
 
Paul Secoy said:
It is a turbo build, but not a super wild one, and there is a budget, sort of. A $500 set of ICONs fits nicely, if such an item exists.

I will keep boost as low as I can to meet my goal, up to 15 Psi max. One of the fellows helping me thinks I will hit my number well below that, I hope he is right. The blocks are really the limiting factor, so I can only push it just so much anyways.
Click to expand...

So ..... and if I'm understanding correctly here, your goal is:
* a stock stroke 400 B Engine
* Cast Iron Heads, either 516 or 906
* and 750 hp on no more than 15 psi Boost
* a Budget

Just make sure whatever Pistons you obtain are a 2618 Alloy Forging, no "4032" alloys allowed.
 
Challenger340 said:
So ..... and if I'm understanding correctly here, your goal is:
* a stock stroke 400 B Engine
* Cast Iron Heads, either 516 or 906
* and 750 hp on no more than 15 psi Boost
* a Budget

Just make sure whatever Pistons you obtain are a 2618 Alloy Forging, no "4032" alloys allowed.
Click to expand...

Yes sir, thats about it. :)

I have the 400, I have the steel crank,I have the heads and valve train, I have the MSD distributor, but will need a new box, I have some of the exhaust, have the turbo, turbo hat for the blow through, have the carb, have a couple transmission choices.

I need, (amongst lots of other goodies):
Machine work, quoted at about $1,300, bore, square deck, align hone, balance, cam bearings, 1/2" pick up, etc. The usual.
Cam and lifters, unless I use one I have here, Timing chain.
Oil pump
Pistons, rings, rods
Head and remaining gaskets

That should about finish up a long block. Hoping $2,000 will cover parts, putting me at under $3500, my unofficial budget. Good thing I have lots of the big stuff.
 
Paul Secoy said:
Yes sir, thats about it. :)

I have the 400, I have the steel crank,I have the heads and valve train, I have the MSD distributor, but will need a new box, I have some of the exhaust, have the turbo, turbo hat for the blow through, have the carb, have a couple transmission choices.

I need, (amongst lots of other goodies):
Machine work, quoted at about $1,300, bore, square deck, align hone, balance, cam bearings, 1/2" pick up, etc. The usual.
Cam and lifters, unless I use one I have here, Timing chain.
Oil pump
Pistons, rings, rods
Head and remaining gaskets

That should about finish up a long block. Hoping $2,000 will cover parts, putting me at under $3500, my unofficial budget. Good thing I have lots of the big stuff.
Click to expand...


I'm guessing Main Studs while you are Align Honing the Mains,if for no other reason to "set/check" vertical Oil Clrc ?
and don't expect the Rods "good to go" OOTB, at a minimum Pin-Fitting of both the Rod small ends and the Pistons will be required, most often a cut & Resizing of the Rod Big Ends to "set" Vertical Brg Oil Clrc/side clrc in pairs.
We're seeing LOTS of sets of Eagle Rods these days that although straight & round is nice OOTB as delivered, as soon as we crack them(8740 capscrews) to even check fastener stretch ? be damned if we can repeat the Big End bore dimension at any Torque/stretch value anywhere close to "as delivered", and we end up having to redo them.
Dunno what's up with that ?
Maybe you wish to move up to the ARP2000 fasteners in whatever Rods you acquire ?

Good luck with your project, running ur fuel a little fat is safe.
 
Challenger340 said:
I'm guessing Main Studs while you are Align Honing the Mains,if for no other reason to "set/check" vertical Oil Clrc ?
and don't expect the Rods "good to go" OOTB, at a minimum Pin-Fitting of both the Rod small ends and the Pistons will be required, most often a cut & Resizing of the Rod Big Ends to "set" Vertical Brg Oil Clrc/side clrc in pairs.
We're seeing LOTS of sets of Eagle Rods these days that although straight & round is nice OOTB as delivered, as soon as we crack them(8740 capscrews) to even check fastener stretch ? be damned if we can repeat the Big End bore dimension at any Torque/stretch value anywhere close to "as delivered", and we end up having to redo them.
Dunno what's up with that ?
Maybe you wish to move up to the ARP2000 fasteners in whatever Rods you acquire ?

Good luck with your project, running ur fuel a little fat is safe.
Click to expand...


Yes, ARP main studs with a girdle for the bottom end. It is the Eagle rods I am most likely to go with, the price is decent, and are rated for more than I should be seeing. Thanks for the heads up on the rods needing to be re fitted, I would not have expected that.

I will be running E85, the guys coaching me along do, and the benefits seem too good to pass up, the extra octane should buy me a little insurance too.
 
Challenger340 said:
I'm guessing Main Studs while you are Align Honing the Mains,if for no other reason to "set/check" vertical Oil Clrc ?
and don't expect the Rods "good to go" OOTB, at a minimum Pin-Fitting of both the Rod small ends and the Pistons will be required, most often a cut & Resizing of the Rod Big Ends to "set" Vertical Brg Oil Clrc/side clrc in pairs.
We're seeing LOTS of sets of Eagle Rods these days that although straight & round is nice OOTB as delivered, as soon as we crack them(8740 capscrews) to even check fastener stretch ? be damned if we can repeat the Big End bore dimension at any Torque/stretch value anywhere close to "as delivered", and we end up having to redo them.
Dunno what's up with that ?
Maybe you wish to move up to the ARP2000 fasteners in whatever Rods you acquire ?

Good luck with your project, running ur fuel a little fat is safe.
Click to expand...

I ordered the .990" pin Eagle rods with the ARP2000 bolt upgrade, thank you for the tips.
 
Paul
What heads?
down .045 will give you no quench
you do not want to run open chamber heads without quench dome/ reverse deflector pistons
so run wedge heads and 0.0 deck dish pistons according to the head cc and gasket selection
something with a more modern combustion chamber that does not require so much advance as the stock really bad spark plug location stock head
 
wyrmrider said:
Paul
What heads?
down .045 will give you no quench
you do not want to run open chamber heads without quench dome/ reverse deflector pistons
so run wedge heads and 0.0 deck dish pistons according to the head cc and gasket selection
something with a more modern combustion chamber that does not require so much advance as the stock really bad spark plug location stock head
Click to expand...

At this point either ported 516's or ported 906's. I don't need or want too much compression with the turbo, and I can get in the range I want with either head. I know I will be a mile off any type of quench. I am considering a 75cc Edelbrock head, but the extra 2K bucks was really not planned for.
 
The best thing about E85 is it's cooling effect. We've run 21lbs with no intercooler. The piston will take more abuse than the rod.
Doug
 
dvw said:
The best thing about E85 is it's cooling effect. We've run 21lbs with no intercooler. The piston will take more abuse than the rod.
Doug
Click to expand...

That is one of the biggest selling points to me also. The 71 Dart my friend is running is carbureted with no intercooler, and he will have frost on his intake after a pass! He just ran 8.12 at 169 mph last weekend, and his car is what finally spurred me to do my first turbo build, he says it is so easy to make power with one its ridiculous. We shall see :)
 
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