Re: which rod for a bracket motor
[Re: rebel]
#2190193
11/05/16 06:44 PM
11/05/16 06:44 PM
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Joined: Feb 2005
Posts: 20,273 PA.
pittsburghracer
"Little"John
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"Little"John
Joined: Feb 2005
Posts: 20,273
PA.
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Honestly there aren't a lot of 900 horesepower 8000 rpm engines on this site. Then subtract the dyno queens, show cars, and cruisers or many can give you good info. Asking for total passes instead of years is the only way you will get good feedback. Forty years plus of racing for me an I hope to have my first 900 horsepower engine next year
1970 Duster Edelbrock headed 408 5.984@112.52 422 Indy headed small block 5.982@112.56 mph 9.38@138.67
Livin and lovin life one day at a time
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Re: which rod for a bracket motor
[Re: rebel]
#2190300
11/05/16 09:41 PM
11/05/16 09:41 PM
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Joined: Jan 2003
Posts: 11,786 Portage,michigan
B3422W5
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 11,786
Portage,michigan
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I brought up the molnar Rod itself breaking because it did. The guy who had that failure is a veteran racer most around these parts know well.
Regards compstar, I ran them for years in a motor that saw 7500 every pass, current owner still has them in the motor. I ran them on the advice of Chuck at Best Machine, who built that motor. He had high praise for them in that price segment. Just relaying my experiences. Those wise asses who cast stones always do.
Last edited by B3422W5; 11/05/16 09:41 PM.
69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight 418 BPE factory replacement headed stroker, 565 lift solid cam, footbrake street/strip car Best so far, 10.32 1/4 1.41 best 60 foot 6.56 at 104.17
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Re: which rod for a bracket motor
[Re: B3422W5]
#2190324
11/05/16 10:00 PM
11/05/16 10:00 PM
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Joined: Dec 2006
Posts: 4,648 aotearoa
rebel
OP
master
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OP
master
Joined: Dec 2006
Posts: 4,648
aotearoa
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I brought up the molnar Rod itself breaking because it did. The guy who had that failure is a veteran racer most around these parts know well.
Regards compstar, I ran them for years in a motor that saw 7500 every pass, current owner still has them in the motor. I ran them on the advice of Chuck at Best Machine, who built that motor. He had high praise for them in that price segment. Just relaying my experiences. Those wise asses who cast stones always do. this is the kind of stuff i want to hear about. Just as someone mentioned 440 Source, i've physicly seen the aftermath of their rods breaking at only 7000 rpm & high 600 HP & it was rod failure, nothing else. I am seriously thinking Compstar but just thought i'd test the waters & see what others might suggest. Thank you for your input.
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Re: which rod for a bracket motor
[Re: rebel]
#2190335
11/05/16 10:12 PM
11/05/16 10:12 PM
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Joined: Jan 2003
Posts: 11,786 Portage,michigan
B3422W5
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 11,786
Portage,michigan
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I brought up the molnar Rod itself breaking because it did. The guy who had that failure is a veteran racer most around these parts know well.
Regards compstar, I ran them for years in a motor that saw 7500 every pass, current owner still has them in the motor. I ran them on the advice of Chuck at Best Machine, who built that motor. He had high praise for them in that price segment. Just relaying my experiences. Those wise asses who cast stones always do. this is the kind of stuff i want to hear about. Just as someone mentioned 440 Source, i've physicly seen the aftermath of their rods breaking at only 7000 rpm & high 600 HP & it was rod failure, nothing else. I am seriously thinking Compstar but just thought i'd test the waters & see what others might suggest. Thank you for your input. Give Best Machine a call and see what those guys recommend. They have never steered me wrong, and always been top shelf in both knowledge and skill.
69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight 418 BPE factory replacement headed stroker, 565 lift solid cam, footbrake street/strip car Best so far, 10.32 1/4 1.41 best 60 foot 6.56 at 104.17
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Re: which rod for a bracket motor
[Re: rebel]
#2190432
11/06/16 12:20 AM
11/06/16 12:20 AM
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Joined: Mar 2006
Posts: 9,982 MI, usa
dvw
master
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master
Joined: Mar 2006
Posts: 9,982
MI, usa
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your possibly right Pittsburgh, but i thought 900 HP & 8k rpm limit might have reduced the possible options for good answers. i guess i need to be more specific even with that info. so looking for... 6.535 length STEEL H beam rods 900HP power output 8000 rpm limit 565grm Custom Ross Pistons No spray 4.250 stroke am i missing anything? Power really doesn't factor into it. That being said mine has a 7500 rpm limit, 4.5 stroke, 157 gram pin, 630 gram piston. If it's a bracket motor the aluminum rods might be out do to number of passes. I ran my BME 300 passes w/o issue before I swapped to Molnar (7.100/2.200/.990). Motor's never been on the dyno but will run 9.0-9.1@146-148 depending on weather at 3350lbs. Doug
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Re: which rod for a bracket motor
[Re: rebel]
#2190582
11/06/16 11:19 AM
11/06/16 11:19 AM
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Joined: May 2005
Posts: 2,072 Apollo, PA.
B1MAXX
top fuel
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top fuel
Joined: May 2005
Posts: 2,072
Apollo, PA.
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your possibly right Pittsburgh, but i thought 900 HP & 8k rpm limit might have reduced the possible options for good answers. i guess i need to be more specific even with that info. so looking for... 6.535 length STEEL H beam rods 900HP power output 8000 rpm limit 565grm Custom Ross Pistons No spray 4.250 stroke am i missing anything? I wouldn't run an h beam in this app. steel billet I beam would be my choice... Crower. That being said the few 900 +hp 8200+rpm engines I have personally touched had BME aluminum rods. My
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Re: which rod for a bracket motor
[Re: B1MAXX]
#2190834
11/06/16 06:18 PM
11/06/16 06:18 PM
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Joined: Mar 2009
Posts: 1,169 Virginia Beach, VA
Old School
super stock
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super stock
Joined: Mar 2009
Posts: 1,169
Virginia Beach, VA
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your possibly right Pittsburgh, but i thought 900 HP & 8k rpm limit might have reduced the possible options for good answers. i guess i need to be more specific even with that info. so looking for... 6.535 length STEEL H beam rods 900HP power output 8000 rpm limit 565grm Custom Ross Pistons No spray 4.250 stroke am i missing anything? I wouldn't run an h beam in this app. steel billet I beam would be my choice... Crower. That being said the few 900 +hp 8200+rpm engines I have personally touched had BME aluminum rods. My definitely this I run Oliver I beam in all my motors. I would not use an h-beam rod in anything over 800 horsepower..
Last edited by Old School; 11/06/16 06:25 PM.
68 cuda formula S 588" bb 5sp 70 CUDA CONVERT 500" 5SP (SUBLIME) 70 CUDA CONVERT 500" 5SP (PLUMCRAZY):TOO MUCH HORSEPOWER, IS ALMOST ENOUGH!
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Re: which rod for a bracket motor
[Re: rebel]
#2190854
11/06/16 07:00 PM
11/06/16 07:00 PM
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Joined: Jan 2003
Posts: 3,511 DFW
mr_340
master
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master
Joined: Jan 2003
Posts: 3,511
DFW
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My $.02 is I haven't been able to get any rod through my machinist's inspection. I bought some Manley Hemi I-beam rods off a SS Hemi racer. They were new in the box. The rod bolts were galled on the threads and under the bolt heads and cap. I paid $1300 for the rods and then another $1000 to get them fixed - new rod bolts, ring dowels, remachine the big ends and touch up the rod bolt seating areas, etc.
I've taken a set of 440 K1 rods and some Manley 440 I-beams to him. The Manleys checked out dimensionally, but the rods were in the mid-20s on the HRC scale, so basically in the annealed or normalized condition for 4340. The K1s were in the mid-30s HRC, but had some ovality in the pin and big end bores.
My machinist likes the Crowers and Carrillos and the CARR bolts. I'm thinking that is the way to go on an all out race engine. Why spend money ($600or so) on new rods, and then have to spend more fixing them? CARR bolts are about $50 each, so that's $800 for rod bolts alone. For the money I got in those Hemi rods, I would have been better off buying Carrillos with better bolts.
Floyd Lippencott IV
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Re: which rod for a bracket motor
[Re: rebel]
#2190856
11/06/16 07:05 PM
11/06/16 07:05 PM
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Joined: Oct 2004
Posts: 3,097 back in Georgia
dthemi
master
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master
Joined: Oct 2004
Posts: 3,097
back in Georgia
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My crank seems to be strong enough to handle the duties but after checking a friends engine that was running less power than I run, I thought it would be a good move to upgrade before we experience the same failings as him. These rods have done 5 seasons n the hardware was changed at last rebuild. The hardware was fine but the rod failed badly Hard to tell from the picture, but it looks like it grabbed the bearing first, with the heat discoloration the picture shows. Were you able to find the bearings from that rod?
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Re: which rod for a bracket motor
[Re: dvw]
#2190900
11/06/16 08:16 PM
11/06/16 08:16 PM
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Joined: Aug 2003
Posts: 1,578
KOS
pro stock
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pro stock
Joined: Aug 2003
Posts: 1,578
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A lot of opinions here. Some from experience on a personal level (Me) some from someone who has done many, many engine builds (DT Hemi), others just quoting what they might have heard. I read a lot. I talk to many people I feel have a good handle on the subject. From what I've gathered gram for gram a H beam will be stronger if the same material is used. The material can be placed in the higher stressed areas with out adding unneeded mass. I suggest talking to Tom Molnar personally. He designed rods at Oliver for many years. My bet is he knows more about rods than most. I agree with DTHemi. Most rod failures have either grabbed a bearing or broke a bolt. I also run extra bearing clearance to combat flex. So far zero rod/bearing failures with my builds. Doug Doug how many runs on the molnar rods so far?
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Re: which rod for a bracket motor
[Re: dvw]
#2190922
11/06/16 09:03 PM
11/06/16 09:03 PM
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Joined: Feb 2005
Posts: 20,273 PA.
pittsburghracer
"Little"John
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"Little"John
Joined: Feb 2005
Posts: 20,273
PA.
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My first build with aluminum rods going in my 1000 plus horsepower build for next year
1970 Duster Edelbrock headed 408 5.984@112.52 422 Indy headed small block 5.982@112.56 mph 9.38@138.67
Livin and lovin life one day at a time
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Re: which rod for a bracket motor
[Re: rebel]
#2191000
11/06/16 10:30 PM
11/06/16 10:30 PM
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Joined: Jan 2004
Posts: 8,657 fredericksburg,va
cudaman1969
master
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master
Joined: Jan 2004
Posts: 8,657
fredericksburg,va
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Hate to say it but I would venture over to the bow tie forums, got to go where the knowledge is on high hp-rpm small blocks, plenty of professional 1000+ hp small blocks built that turn 8000 to 11,000. I'm sure they have found what works and don't. Happy hunting.
Last edited by cudaman1969; 11/06/16 10:31 PM.
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Re: which rod for a bracket motor
[Re: rebel]
#2191229
11/07/16 06:24 AM
11/07/16 06:24 AM
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Joined: Jan 2003
Posts: 2,935 Finalnd, Perkele
jyrki
master
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master
Joined: Jan 2003
Posts: 2,935
Finalnd, Perkele
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I have used Tom's rods, run them for 8 years with 1500+ hp, no problems. They were checked for cracks two years ago and one had some because it had been hurt in a lifter failure, but never broke.
Plynouth VIP '67 TT IC EFI
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