Search seems to be completely broke lately.

Ive been running LS cranks and rod sizing for years now. Its all ive ever used. Now im thinking maybe to go to the GSR crank and rods for future builds.

Thoughts? Who uses what in their 900+ hp builds?

 

I think the Manley turbo tuff is going to be the most common steel rod and GRP for aluminum.

 

in for this, we were having this discussion a few weeks ago.

 

Not really worried about brands more than the ls vs gsr rod and crank combo.

I'm a Manley Tt or GRP al guy myself

 

i have used ls cranks for my AM builds and seems to make good power. my car has a gsr crank because thats what i had in front of me at the time lol. a back to back dyno would be nice but its going to be hard to find anyone giving out info like that if they had it.

 

I can see it being a better choice for a motor car but for a boosted car does it really make a difference? Does the gsr setup spin up smoother? Better out of box design for 10500-11000 rpm boosted output?

 

Displacement really is going to be the only differentiating factor here. The storke difference is minimal but it helps. As far as reving smoother i don't see a difference. So long as the rotating assembly is well balanced and assembled 89mm-87.5mm stroke will take the rpm either way. The GSR has wider bearings but I've personally never seen an issue with the LS bearings being more narrow but thats my personal experience.

 

You've got that backwards. Gsr bearings and rods are narrower.

 

Correct.
I've always used LS cranks.

 

Yes you are correct that's my mistake.

 

what rods?

 

i dont really have much input here but id like to know you guys opinions as well. i used an ls crank and ls length rods in my last build and i was happy with it. revving to 9500 without an issue. im using a GSR crank and manley TT gsr rods in my current build which will also probably be limited to 9500 rpm unless i see the need for more.

 

it's pretty well evenly tossed up as to who uses what apparently.

 

ls crank for me and an old friend.

 

GSR motor with LS crank and custom rods & pistons.

 

well maybe ill stay with the LS. Has anyone seen more or the same skirt wear from either stroke?

 

Run whatever you have and can easily get parts for. I don't think you will notice much of a difference. You won't be gaining hp doing down to a gsr stroke thats for sure. The piston will be pretty happy in either of those small strokes.

 

well i have both cranks. I can get rods. I'm just trying to see if there is a benefit in the smaller stroke. I rev to minimum 10,500. I dont care about a 20hp or whatever difference in strokes if that means anything.

 

I have used both cranks and both aluminum rods and steel, I rev to 11.5k on track, I'm doing next big build with GSR stroke and GRP rods. I like the GSR stroke better. Good luck Matt!

 

I'm just curious about your piston skirts and side loading with the LS crank and rods with the 11k rpm's:

What do you see when you rebuild?

What keeps your bottom end together?

Do you have an aftermarket girdle?

 

i do get skirt collapsing over time (I gain about 4-5 thousandths over an extended period but it never hurts anything other than a little bit more blow by....currently i believe due to the clearance im running on ethanol versus what i should be running for the fuel. I havn't corrected it because i would have to go to 85mm to do so and id rather extend the life of my block than worry about beating up a few pistons per year. It runs great haha.

Would a GSR stroke be more forgiving in a large clearance situation?

 

What do you mean gain 4-5 thow ?

 

I gained that much clearance but there's no scarring on the piston. the piston to wall clearance gets bigger from slap i guess. Engine sounds normal once warmed up and has some clicking at cold temps

 

How is that possible? Is the piston now oblong? Is it changing the ptw on the pin ends of the piston?

 

no not on the sides. Its plenty possible....the skirt at the bottom gets beat inward from thrust. I've recorded this a few times in my history trying large clearances.