Engine Stroking, Long Connecting Rods, Short Connecting Rods

turbinetom

Active Member
Joined
Jul 14, 2019
Ok...based on the title of this thread, why the hell has this thread not had at least one damn joke posted? I've been watching for days to see who will fire the first shot....
 

Grumpy

Thread killer
Joined
May 24, 2001
Stock ported heads, 206 roller cam, stroke kit and smaller turbo, matching converter and 3.42 gears. What rear gear are you running?

Ok here is the first joker. ;)
Ahhhh...one of the best the keyboard warriors . :rolleyes: How the hell would YOU know ? Look at your combo..".NEW ENGINE/ TRANS--stock stroke forged internals, billet caps, ported/polished iron heads, 214/210 billet cam, Morel roller lifters, T&D roller rockers, TA headers, Turbonetics billet 64/65 turbo, EA Stage II n/l trans, 9" 3000 stall n/l converter. Best et 11.044 @ 123.04 at 20 psi." . 9 sec capable car running 11s :unsure: :ROFLMAO:
 

BEATAV8

The Engine Whisperer
Joined
Feb 14, 2002
Got E85 available? Give it some compression ratio.
DSS racing piston in St Charles IL sells Buick pistons with a small dish "off the shelf". With a stock stroke they'll get you into the 10.3-10.6:1 range depending on your bore and other geometry details. Runs nice that way.
 

turbinetom

Active Member
Joined
Jul 14, 2019
I do like this site as there are some prety good people on here that offer genuine advice, often based on personal experience. I cant add much to this thread but only offer that a few weeks back I saw the "Engine Masters" episode wherby they build ( the the ability it can be) 2 identical engines, one long rod, one short rod. The were big chevy's but Id think it would translate. Dyno testing showed almost zero difference in the 2 engines. I believe it simply shifted some of the torque and hp numbers a bit on the very top end. Its worth a watch if you can fnd the episode.
Regards,
Tom
 

~JM~

Wrinkled Member
Joined
Oct 31, 2007
From what I recall from my reading & informal study on this subject, the long rod combination may provide longevity benefits due to less friction & sidewall loading between piston & cylinder. Typically the pistons end up being lighter also.

Look at the longevity history of the OEM 400ci SBC. That was a short rod combination.
 

~JM~

Wrinkled Member
Joined
Oct 31, 2007
I read up on the longer rod length & stroker benefits in naturally aspirated engines many years ago. I recall these to be an interesting write ups:

http://victorylibrary.com/mopar/rod-tech-c.htm

The long rod sounds beneficial until it intrudes into the ring lands.

Hmmm... There are two links to articles listed above. Don't know why it formatted the way it did in original post
 

Pronto

You can't knock them up with spit.
Joined
Dec 9, 2002
Ok here is the first joker. ;)
Ahhhh...one of the best the keyboard warriors . :rolleyes: How the hell would YOU know ? Look at your combo..".NEW ENGINE/ TRANS--stock stroke forged internals, billet caps, ported/polished iron heads, 214/210 billet cam, Morel roller lifters, T&D roller rockers, TA headers, Turbonetics billet 64/65 turbo, EA Stage II n/l trans, 9" 3000 stall n/l converter. Best et 11.044 @ 123.04 at 20 psi." . 9 sec capable car running 11s :unsure: :ROFLMAO:
The 700r doesn't last getting beat on, especially in a heavy car, you know that.
 

GoreMaker

Member
Joined
May 7, 2021
The 700r doesn't last getting beat on, especially in a heavy car, you know that.
I dunno about that. The 700R4 was the transmission in 1/2 ton trucks that were rated to tow beyond 7000 pounds. They were used in full size B body cars before the switch to the LT1, which were also rated for towing beyond 5000 pounds. The early models from before the mid-80s were pretty garbage, but those defects got resolved. PerformaBuilt sells 700R4 transmissions that'll handle anything from 450hp to 1000+hp, including some reliable towing ones. There's plenty to like about the 700R4 (and some stuff to dislike too).

In any case, off topic to this thread.
 

Grumpy

Thread killer
Joined
May 24, 2001
The 700r doesn't last getting beat on, especially in a heavy car, you know that.
look at Smittys.. BUT thats built to the hill. But the wagon is still 700#s heavier. I had a 200all billet junk ready to go but never made it into the car. To many cars to play with. Although it was an awesome truck.

Sooooo how fast do ya want to go in this ?
 

Pronto

You can't knock them up with spit.
Joined
Dec 9, 2002
Everthing Smitty built was over the top, way beyond the average performance build anyone would do...
 

turbinetom

Active Member
Joined
Jul 14, 2019
Ive read on this subject quite a bit as well and feel I have a good understanding as far as side loading, dwell ect.. All of the reading however is always theoretical, seeing it put in practice on a dyno is somewhat different.
 

Grumpy

Thread killer
Joined
May 24, 2001
All of the reading however is always theoretical, seeing it put in practice on a dyno is somewhat different.
I call it the woulda, shoulda, coulda's. Talk is cheap. SHOW ME what it can do. Get a stroker kit an let the fun begin. What a sleeper it would be. ;)
 

ravege

Active Member
Joined
Jul 10, 2008
Everything I know about engine building tells me that de-stroking results in less low-end torque, which is exactly the opposite of my goal. Especially with the heavy car this engine is moving around, this doesn't seem very beneficial.
I think he might have been referring to the fact that with split pin cranks, the longer the stroke - the less material, or overlap, of connecting rod throws on the crank and therefore "weaker" than stock or short stroke cranks.
 

DaveyX87

Member
Joined
Oct 22, 2012
I am in the process of a rebuild as well. To stroke , or not to stroke, that is the question. I see GN1 offers two different kits, stroker and long rod stroker. I am not sure which to choose. The car is primarily street driven. I don't want to sacrifice drivability (I was told stroking in the street is not good). Thoughts?
 

GoreMaker

Member
Joined
May 7, 2021
I'm currently leaning towards stroking, mostly for the improved low end torque and faster turbo spooling. A long rod kit maintains the stock rod/stroke ratio and reduces the chance of potential accelerated cylinder wall wear that a shorter rod/stroke ratio could cause. However if you're looking for high-RPM horsepower, a higher RPM range and better turbo efficiency within that higher range, you're probably better off with a stock stroke (or even de-stroking at the extreme). In my case, I'm moving a 4500 pound car, so the priorities are different
 

626gn

Well-Known Member
Joined
Feb 15, 2009
I am in the process of a rebuild as well. To stroke , or not to stroke, that is the question. I see GN1 offers two different kits, stroker and long rod stroker. I am not sure which to choose. The car is primarily street driven. I don't want to sacrifice drivability (I was told stroking in the street is not good). Thoughts?
Perhaps they were referring to a different type of “stroking in the street” :ROFLMAO:. Joking aside, you will not be sacrificing drivability by going stroker. The long rod stroker, theoretically, should give you more torque at lower rpm’s by virtue of the added cubic inches but some well respected Buick people claim there is no discernible advantage. In any case I doubt there are any max power gains over the stock stroke but I’m not an expert in the matter. Going stroker does however come with additional costs to clearance the block. If money is tight perhaps it’s best spent elsewhere? Imo, more important than the stroke or not to stroke decision is deciding on the right builder to do the job.

Having said that, I went the long rod stroker route because that’s what my trusted builder recommended (he knew this was going to be a street car). Final compression ended up being 9.4:1. FWIW, with the same 66mm turbo that was on my stock bottom end motor, this new motor is a night and day difference in the seat of the pants.
 
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