? stock rods
- Thread starter MrNurse
- Start date
dgoodhue
BuSTeD 4.3
Re: ? stock rods
Buy a set of used L35 rods, I have seen them for FS for $75. You will spend more than that beefing up a set of LB4 rods that will never be as strong. The only reason the stock rods cope inside in syty motor is because of the low RPM of the motor.
MrNurse said:
Buy a set of used L35 rods, I have seen them for FS for $75. You will spend more than that beefing up a set of LB4 rods that will never be as strong. The only reason the stock rods cope inside in syty motor is because of the low RPM of the motor.
DaveP
Active member
Re: ? stock rods
I looked at a set of LB4 rods (Typhoon take-out), and a set of L35 rods (1995 Astro Van) that I have here in my shop. They look the same, seem the same, ARE the same. The Part Number in the GM microfisch is 10201166. This is the number for ALL 4.3' connecting rods from 1991 to 1994 ( the coverage of my microfisch)( All= Ty, Sy, LB4, L35). There are NO "casting numbers" (the rods are forged anyway, not cast). But there are no numbers of any kind on the rod.
There is a later version of the rod. The cap looks different. HOWEVER: It is sold under the same PN as the earlier rod, so it's considered a direct replacement. It (the cap) does not look as strong as the early rod. Plus I know the balancer is different on the later-rod engines. May be weight issues as well.
In closing: There ISN'T ANY DIFFERENCE between an LB4 rod and an L35 rod at least prior to 1996 (1995 was the last year of the L35 anyway). It's the same part. This rumor (that there is a difference) came up years ago, but I discovered it to be un-true during research when I ended up with a bunch of 4.3 engines in my shop over a short period of time. Plus the P/N is the same. I'm surprised that the rumor still circulates....
You may 'feel' better, that you have "L35 rods" in your engine. But you won't have improved a thing.
DaveP
dgoodhue said:
I looked at a set of LB4 rods (Typhoon take-out), and a set of L35 rods (1995 Astro Van) that I have here in my shop. They look the same, seem the same, ARE the same. The Part Number in the GM microfisch is 10201166. This is the number for ALL 4.3' connecting rods from 1991 to 1994 ( the coverage of my microfisch)( All= Ty, Sy, LB4, L35). There are NO "casting numbers" (the rods are forged anyway, not cast). But there are no numbers of any kind on the rod.
There is a later version of the rod. The cap looks different. HOWEVER: It is sold under the same PN as the earlier rod, so it's considered a direct replacement. It (the cap) does not look as strong as the early rod. Plus I know the balancer is different on the later-rod engines. May be weight issues as well.
In closing: There ISN'T ANY DIFFERENCE between an LB4 rod and an L35 rod at least prior to 1996 (1995 was the last year of the L35 anyway). It's the same part. This rumor (that there is a difference) came up years ago, but I discovered it to be un-true during research when I ended up with a bunch of 4.3 engines in my shop over a short period of time. Plus the P/N is the same. I'm surprised that the rumor still circulates....
You may 'feel' better, that you have "L35 rods" in your engine. But you won't have improved a thing.
DaveP
dgoodhue
BuSTeD 4.3
Re: ? stock rods
This is the first I have ever heard of this. Any chance that some of the motor were replacements? The same part number doesn't surprise me as GM is alway superceding the part number anyways, the original SyTy part is different for the rods anyways.
http://www.syty.net/forums/showthread.php?t=30734&highlight=10201166
Leroy, claims he had 2 LB4 and 4 L35 Rods. I would be willing to pull the LB4 out my Scylone block this comjng weekend to take some pictures, the motor is an original numbers matching and I am 99.99% sure its original.
DaveP6999 said:
This is the first I have ever heard of this. Any chance that some of the motor were replacements? The same part number doesn't surprise me as GM is alway superceding the part number anyways, the original SyTy part is different for the rods anyways.
http://www.syty.net/forums/showthread.php?t=30734&highlight=10201166
Leroy, claims he had 2 LB4 and 4 L35 Rods. I would be willing to pull the LB4 out my Scylone block this comjng weekend to take some pictures, the motor is an original numbers matching and I am 99.99% sure its original.
cloneman315
Active member
Re: ? stock rods
if your in there put in the good ones eagle etc
if your in there put in the good ones eagle etc
Re: ? stock rods
i would but i am on a strict budget. so i am gonna use the best parts i can afford. also i do not ever plan on making 700 800 or 900 hp, so as long as i have it tuned right and do not spark knock it to death, i do not need the parts in there that will demand that quality or price. i am shooting for around 500 CRANK HP. obviously not WHP. I am not gonna build a motor that I do not NEED. I am researching what will need to be done to make this power without going into overkill mode. i will say if i had no budget and could go crazy, i would throw the most expensive parts in there i could find just so i could have the BEST. i appreciate all the feed back and this is why i enjoy this community so much......all the experience and knowlege.
so thanks, and keep it coming
i would but i am on a strict budget. so i am gonna use the best parts i can afford. also i do not ever plan on making 700 800 or 900 hp, so as long as i have it tuned right and do not spark knock it to death, i do not need the parts in there that will demand that quality or price. i am shooting for around 500 CRANK HP. obviously not WHP. I am not gonna build a motor that I do not NEED. I am researching what will need to be done to make this power without going into overkill mode. i will say if i had no budget and could go crazy, i would throw the most expensive parts in there i could find just so i could have the BEST. i appreciate all the feed back and this is why i enjoy this community so much......all the experience and knowlege.
so thanks, and keep it coming
DaveP
Active member
Re: ? stock rods
The Typhoon rods mentioned in first post ARE replacements
See below, re replacement engines.
The P/N remains the same ONLY if the new part is satisfactory for the original application. If there are differences (heat treating, bolt quality, etc) for various applications, then there will be different P/Ns.
It took a minute to remember this. You're correct: The cap on the SyTy rod is the same as the 'later' P/N 10201166 I refered to as the "later replacement" in my first post. Different from the rods I found in a 92,93, &95 L35, AND a 91 LB4 from a S-10 pick-up. (Not a Syclone).
BUT! There's only ONE P/N for EVERY 4.3 made from 91 to 94. Find me a P/N for a SyTy rod other than 10201166. You can't do it. That's the ONLY P/N there is. And as I just said, if there are differences in hardware, or processes, there will be different P/Ns. Same P/N= same part.
So I was correct in my first post, that I feel the 'later' (same as SyTy) bearing cap doesn't "look as strong" as the first design ( what you're calling the L35)?
I looked at these. They're 'early-cap', 10201166's, Used in L35s AND LB4.
He's refering to the differences in the caps. Same P/N, though.
They'll look like any other rod from 91 to 95. Except for the caps.
Another thing: Many, many of these trucks had replacement engines installed under warranty by dealers and others when 'replacement' engines were still available. There was much discussion about these engines, 10 or so years ago. At the time, we concluded that these engines had "flat top, regular ole' LB4 pistons". I have found (3) trucks with replacements that had the "L35 rod" AND the LB4 flat-top pistons. (And at least one rod was bent in each one of them!!)
Therefore, I consider the same rod to be installed in either LB4 or L35. And just as prone to bending, when installed in SyTy.
I forgot that the SyTy had a different-appearing rod cap. But it's the same rod.
DaveP
dgoodhue said:
The Typhoon rods mentioned in first post ARE replacements
See below, re replacement engines.dgoodhue said:
The P/N remains the same ONLY if the new part is satisfactory for the original application. If there are differences (heat treating, bolt quality, etc) for various applications, then there will be different P/Ns.
dgoodhue said:
It took a minute to remember this. You're correct: The cap on the SyTy rod is the same as the 'later' P/N 10201166 I refered to as the "later replacement" in my first post. Different from the rods I found in a 92,93, &95 L35, AND a 91 LB4 from a S-10 pick-up. (Not a Syclone).
BUT! There's only ONE P/N for EVERY 4.3 made from 91 to 94. Find me a P/N for a SyTy rod other than 10201166. You can't do it. That's the ONLY P/N there is. And as I just said, if there are differences in hardware, or processes, there will be different P/Ns. Same P/N= same part.
So I was correct in my first post, that I feel the 'later' (same as SyTy) bearing cap doesn't "look as strong" as the first design ( what you're calling the L35)?
dgoodhue said:
I looked at these. They're 'early-cap', 10201166's, Used in L35s AND LB4.
dgoodhue said:
He's refering to the differences in the caps. Same P/N, though.
dgoodhue said:
They'll look like any other rod from 91 to 95. Except for the caps.
Another thing: Many, many of these trucks had replacement engines installed under warranty by dealers and others when 'replacement' engines were still available. There was much discussion about these engines, 10 or so years ago. At the time, we concluded that these engines had "flat top, regular ole' LB4 pistons". I have found (3) trucks with replacements that had the "L35 rod" AND the LB4 flat-top pistons. (And at least one rod was bent in each one of them!!)
Therefore, I consider the same rod to be installed in either LB4 or L35. And just as prone to bending, when installed in SyTy.
I forgot that the SyTy had a different-appearing rod cap. But it's the same rod.
DaveP
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Quickstop [UK]
Combating adversyty.
Re: ? stock rods
weren't there two different factories that made the rods with slight variations on the big end? Something beginning with R for one of them and meant you couldn't use them in a Ty?
weren't there two different factories that made the rods with slight variations on the big end? Something beginning with R for one of them and meant you couldn't use them in a Ty?
dgoodhue
BuSTeD 4.3
Re: ? stock rods
I am not here to argue part numbers, just to find out the correct info. I was alway under the impression the L35/L31 rods were stronger, I have never had them in my hands so I am only going by net research.
This topic is of great interest to me as I was going to use them in a budget build (I have beed delay 4-6 weeks due my parents selling their house and myself helping them move, I should have had them installed by now) Maybe that delay ended up being a good thing for me. Most of the bent broken rods I have seen are on the skinny end of the rods (piston pin), so if they are no stronger on that end then that affects my decision greatly.
I am not here to argue part numbers, just to find out the correct info. I was alway under the impression the L35/L31 rods were stronger, I have never had them in my hands so I am only going by net research.
DaveP6999 said:
This topic is of great interest to me as I was going to use them in a budget build (I have beed delay 4-6 weeks due my parents selling their house and myself helping them move, I should have had them installed by now) Maybe that delay ended up being a good thing for me. Most of the bent broken rods I have seen are on the skinny end of the rods (piston pin), so if they are no stronger on that end then that affects my decision greatly.
Re: ? stock rods
so there was only one rod in the early 90s what about the rods in later years, 98+ and they all share the same dimensions and chevy superceedes so they would all have the same part number as they would all be new/revised/improved/?cheaper? parts. right? also, i am thinking of getting rid of the truck for something with a back seat, i had an offer for a 87 t type, not a gn. it looks pretty clean from the one picture i saw. any input on that?
so there was only one rod in the early 90s what about the rods in later years, 98+ and they all share the same dimensions and chevy superceedes so they would all have the same part number as they would all be new/revised/improved/?cheaper? parts. right? also, i am thinking of getting rid of the truck for something with a back seat, i had an offer for a 87 t type, not a gn. it looks pretty clean from the one picture i saw. any input on that?