Stroked GSR or some kinda varriation... Question.

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LOWLIFE

Local Diesel Fanatic
Ok so I sold my ED and ended up with a del slow but none of that matters, what matters is it is called a del slow for a reason, I loved my ED with a B20B from a CRV and it had a bunch of bolt on stuff and some juice just cause. well i want to do another B series swap since it is the most economic for me at this point in time.

I want to do a LS/VTEC but it would be obvious what i did so i changed my mind...

If i get a stock GSR block and use LS crank and connecting rods in it will there be any clearance issues with the oil squirters or anything else? and the LS crank is a direct bolt in correct? i mean it should be since you can use the GSR girdle on the LS... and the pans are interchangeable (well GSR pan needed to clear girdle, but you get the idea). Im sure a couple of you follow what im wanting to do here. I dont see any foreseeable issues with my idea and i think it to be a good way to go since the LS has a longer stroke and longer rods than the GSR but i get the added benifit of the piston oil squirters and it being a stock VTEC block. basically it will just get new guts and it makes it a stroker of sorts (since it is) but externally it can look like a basic GSR. :D

This works right? i mean im sure someone has done it before if not many people.
 
LS rods are actually SHORTER than gsr rods. it's the crank that is physically bigger.

Crank stroke:
B18C1 and B18C5..........87.2 mm
B18 A/B and B20B/Z ......89.0 mm

Rod length:
B18A/B or B20B/Z 137 mm
B18C's 137.9 mm


with ls rods/crank, you will still need to go to 83mm bore (requiring sleeves) to hit 1.9L... at 82mm, you're only at 1840cc or so, and 82mm pistons are a bit rare. 81.5's are more common for an overbore.

This is a pretty good articles with a ton more details:
Engine Package : Swapping Parts For Power - Team Integra
 
I found 82mm nippon pistons on ebay, they are $150 with rings.

What you are trying to do is very common, its easy but you have to get things machined.

You will have to machine the big end of the rods and caps, same for the mains, then you have to get it all line bored. once done you can install the LS crank and rods to the GSR.

The oil squirters have to be bent off to the side, or removed and plugged. once all that is done your ready to rock.

LS Vtec in a GSR block!

make sure you bump your compression to above a 11:1 to get thing going well.
 
LS rods are actually SHORTER than gsr rods. it's the crank that is physically bigger.

Crank stroke:
B18C1 and B18C5..........87.2 mm
B18 A/B and B20B/Z ......89.0 mm

Rod length:
B18A/B or B20B/Z 137 mm
B18C's 137.9 mm


with ls rods/crank, you will still need to go to 83mm bore (requiring sleeves) to hit 1.9L... at 82mm, you're only at 1840cc or so, and 82mm pistons are a bit rare. 81.5's are more common for an overbore.

This is a pretty good articles with a ton more details:
Engine Package : Swapping Parts For Power - Team Integra

yes you are correct on the rod lengths, i was not thinking but was aware of this.

Im not really looking to go to a very large bore, just wanting to go .20 over making them a 81.5mm piston for a standard rebuild and a little bump in compression and just a hair more cc's.

and thanks for the link, i will take a look at it here shortly

I found 82mm nippon pistons on ebay, they are $150 with rings.

What you are trying to do is very common, its easy but you have to get things machined.

You will have to machine the big end of the rods and caps, same for the mains, then you have to get it all line bored. once done you can install the LS crank and rods to the GSR.

The oil squirters have to be bent off to the side, or removed and plugged. once all that is done your ready to rock.

LS Vtec in a GSR block!

make sure you bump your compression to above a 11:1 to get thing going well.

engine is getting rebuilt, im familiar with this process so im not worried and am aware of the potential cost for the work to be done. I'm not familiar with those pistons, im looking to run forged pistons and rods, car will get N2O and likely to run a low boost setup later just for fun.

why are you saying i will need to machine the crank end of the rods (big end) if they are already matched to the ls crank...

everything will also be balanced to help ensure longevity of this engine that im sure will be ran hard.

and why are you saying i will have to run 11:1 compression or higher to get it going well? i know the GSR is 10.8:1 stock and i had already planned on 11.5-12:5 area as a final compression ratio. I need to be able to run it on 93 octane pump gas as the car will be driven often and E85 isnt always readily available. I plan on Hondata S300 and a professional dyno tune to get it all synced and set up after the engine break in. but to begin with a sharp ear and careful timing will be my savior.

and what is it that will contact the oilers? part of my reasoning for the block is for the additional lubrication at the piston skirts. not to mention the hidden LS/VTEC as a major plus as well.

EDIT:
finding conflicting info on stock compression ratio for the GSR... but i think the 10:1 ratio for the GSR and 10.6:1 for the ITR seems alot more correct than the supposed 10.8:1 for the GSR that i previously found.
 
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engine is getting rebuilt, im familiar with this process so im not worried and am aware of the potential cost for the work to be done. I'm not familiar with those pistons, im looking to run forged pistons and rods, car will get N2O and likely to run a low boost setup later just for fun.

why are you saying i will need to machine the crank end of the rods (big end) if they are already matched to the ls crank...

everything will also be balanced to help ensure longevity of this engine that im sure will be ran hard.

and why are you saying i will have to run 11:1 compression or higher to get it going well? i know the GSR is 10.8:1 stock and i had already planned on 11.5-12:5 area as a final compression ratio. I need to be able to run it on 93 octane pump gas as the car will be driven often and E85 isnt always readily available. I plan on Hondata S300 and a professional dyno tune to get it all synced and set up after the engine break in. but to begin with a sharp ear and careful timing will be my savior.

and what is it that will contact the oilers? part of my reasoning for the block is for the additional lubrication at the piston skirts. not to mention the hidden LS/VTEC as a major plus as well.

EDIT:
finding conflicting info on stock compression ratio for the GSR... but i think the 10:1 ratio for the GSR and 10.6:1 for the ITR seems alot more correct than the supposed 10.8:1 for the GSR that i previously found.

you want to get the big ends of the rods line honed so the bearings have a nice surface to stick to. Its common practice when you rebuild a engine.

if you dont bend the oil squirters the rod cap will come into contact with it. causing problems on start up. If you plug em nothing will happen but a rise in oil pressure.

so this high comp engine will see low boost and nitrous? why not just boost it or a big shot of nitrous?

Like B said, the GSR is a 10:1 comp. 11:1 compression ratio will allow mild cams to breath better. 12:1+ will allow large cams to make power on the top end.

with 93 pump I would run a 13:1 comp ratio. ;)

some guys here in cali are running a 13:1 comp ratio on 91 cali garbage gas.
 
you want to get the big ends of the rods line honed so the bearings have a nice surface to stick to. Its common practice when you rebuild a engine.

if you dont bend the oil squirters the rod cap will come into contact with it. causing problems on start up. If you plug em nothing will happen but a rise in oil pressure.

so this high comp engine will see low boost and nitrous? why not just boost it or a big shot of nitrous?

Like B said, the GSR is a 10:1 comp. 11:1 compression ratio will allow mild cams to breath better. 12:1+ will allow large cams to make power on the top end.

with 93 pump I would run a 13:1 comp ratio. ;)

some guys here in cali are running a 13:1 comp ratio on 91 cali garbage gas.


maybe will see boost, if it does it will be some time in the future, but will 100% for sure see nitrous. and after some looking i may end up using a B16 block since its more readily available (and more of a sleeper) and i think as long as i use the right length rod it should be fine. guess i was more hung up on the GSR for the oil squirters but they arnt really a gotta have.

and WOW 13:1?? seems really high for just 91 rating. If it can run it at that octane then i will run the compression up there! and i was thinking something else on the rods, they will all be properly prepped by a machine shop as well as crank micro polished ect.

also should i install a block guard? i mean i dont really think i will have a problem with the sleeves walking as it may never see boost and if it does it will be a lower boost... now would be the time while it is apart and when i get the cylinders cut .020 over.

are they cheap insurance? or a waste of cash? i mean they are less than 100 bones...
 
the problem with the b16a block is you cant put a LS crank in there. The deck hight is too low.

There is something called a tech 43 build but its more of a track engine than a street engine(it smokes like a coal train after a short time)

you best bet would be a GSR block or a b20 vtec.

Yes 13:1 is doable with 91. my tuner is very comfy with a 13:1 on 91. make sure your tuner is ok with that high of a comp on 93.

when you tune on nitrous make sure you use race gas, to maximize your HP and TQ output.

dont use a block guard, they are a waste of cash. the only reason i ran a block gaurd was because it was already in the block and my machinist told me to leave it in because If we took it out we might distort the cylinders.

If your worried about the cylinders getting distorted get some post installed in the water jackets BEFORE they bore and hone the cylinders.
 
I ran 12.6 on 92 octane, 12.8 with good timing on 93 octane. With large cams, you can definitely run 13:1 on 91.
 
the problem with the b16a block is you cant put a LS crank in there. The deck hight is too low.

There is something called a tech 43 build but its more of a track engine than a street engine(it smokes like a coal train after a short time)

you best bet would be a GSR block or a b20 vtec.

Yes 13:1 is doable with 91. my tuner is very comfy with a 13:1 on 91. make sure your tuner is ok with that high of a comp on 93.

when you tune on nitrous make sure you use race gas, to maximize your HP and TQ output.

dont use a block guard, they are a waste of cash. the only reason i ran a block gaurd was because it was already in the block and my machinist told me to leave it in because If we took it out we might distort the cylinders.

If your worried about the cylinders getting distorted get some post installed in the water jackets BEFORE they bore and hone the cylinders.

is there not a short enough rod available to run the LS crank in there? I figured surely there would be.

and good call on the tunner being ok with the compression ratio. Im still trying to find a good block for the swap, i have a B18a1 sitting in the shed already that i have had for some time but i really want a factory VTEC engine so it will be more of a sleeper.
 
see if you shorten the rod and add a bigger stroke your back at square one. Also your rod ratio would be off.

If you already have the B18 block I would say do a LS vtec on it. if you want a oem vtec engine then you will need a GSR.

I personally wouldnt buy a good GSR just to add a LS crank and rods in it. What I would do is find a GSR with a spun rod bearing and rebuild it. Make sure you open it up before you buy and look at the walls, measure them if possible.

If you dont want to go that route then you can buy a GSR bare block with mains and go from there.
 
see if you shorten the rod and add a bigger stroke your back at square one. Also your rod ratio would be off.

If you already have the B18 block I would say do a LS vtec on it. if you want a oem vtec engine then you will need a GSR.

I personally wouldnt buy a good GSR just to add a LS crank and rods in it. What I would do is find a GSR with a spun rod bearing and rebuild it. Make sure you open it up before you buy and look at the walls, measure them if possible.

If you dont want to go that route then you can buy a GSR bare block with mains and go from there.

Shortening the rods does not decrease the stroke and they pistons will still have the proper range of movement and displacement. you are correct about the rod ratio however and it would be stressfull on the piston walls and rings ect.

I prefer a pretty bare GSR for my project since it will be cheaper

I dont like GSR engines so thats why the LS internals

It will be a LS/VTEC... but i dont want it to be know by looking at it, more of the sleeper thing cause i think it will be fun.

now we are on the same page.:D
 
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