Noob Turbo L-16 from Hell

[Draker]

second time it has broken hehe

 

 

 

Anyone know if I can use Sr20 rods in an l20b? I need forged pistons and gonna buy SR20 pistons if they can fit. 

 

My L20b is .030 over, I'm willing to pay the shop again to go over to 86mm. I read somewhere on the 510 realm that sr20 rods are the same height as L20b rods. But are the bottom large ends the same. 

 

Also read about this guys L20b rod combo with SR pistons but I don't know the details or much about [pin height]

http://community.ratsun.net/topic/1793-my-73-620-t/

 

 

They are rather weak transmissions.. but good for putting around with.

[nl320what]

SR20DE rods are 9mm shorter

[datzenmike]

136.9mm????

 

I wrote down once that SR pistons have a 32mm pin height?

[nl320what]

SR20 Piston/Rod:

Bore/Stroke= 86.00/3.386 Std.   Rod Length= 5.366 / 136.3 Piston Pin Height= 1.26 / 32

 

I havent had very long life in an L/Z 4-banger when you start revving it with a 2.0L or bigger setup.

 

SR20 block is very much stronger to handle flex.

[datzenmike]

L20b bored to 86mm

152.5mm Z20E rods

SR20 32mm pin height pistons 12cc dish modified (bushed) to take Z20E pin

 

 L20B block is 227.45mm tall

152.5 + 32 + (1/2 86mm stroke) 43mm = 227.5mm

 

Piston is 0.05mm above deck

Compression is 10.57 if flattop

Compression is 8.71 if 12cc dish.

[KoHeartsGPA]

Don't toss the dogleg if you remove it!

 

I'd take it, if you weren't so far away.

I can bring it to you.

[nl320what]

L20b bored to 86mm

152.5mm Z20E rods

SR20 32mm pin height pistons 12cc dish modified (bushed) to take Z20E pin

 

 L20B block is 227.45mm tall

152.5 + 32 + (1/2 86mm stroke) 43mm = 227.5mm

 

Piston is 0.05mm above deck

Compression is 10.57 if flattop

Compression is 8.71 if 12cc dish.

 

That would be the correct combo, Z20E Rods and SR20 Pistons :)

[datzenmike]

Pretty much the perfect combo forged piston, long rod, 1997cc L20B.

[That4doorKiD]

well darn, I just bought flat tops!

[datzenmike]

Then probably premium fuel for you. The thing is, your efficiency will be much higher than regular gas and lower compression. Probably once tuned, you will be getting more miles per gallon but the gas will cost more. Hopefully the extra miles will offset the cost.

[That4doorKiD]

Flat tops with L20b rods. Lower compression would make it better for mpg?

[datzenmike]

well darn, I just bought flat tops!

 

 

Flattop what???? SR20 pistons???? With L20B rods??? I already explained what will happen with this combo. From crank center line to top of block is 227.45mm. Half the stroke is 43mm so 184.45mm left. SR20 pin height is 32mm so 152.45mm left. If you run an L20B rod which is 145.9 mm long you will have 6.55mm of cylinder space left that is not being used. This volume, 6.55mm x 86mm diameter, is 38 extra ccs added to the 45.2 combustion chamber plus the gasket volume of 6.9cc. Your combustion chamber is now 90.1cc. An 86 x 86 B&S cylinder is 499cc and your compression will be 6.5. This is so pathetic a compression it will just barely idle.

 

If you have changed your mind about the 152.5mm rods and SR20 pistons and mean 86mm flatops from an L28 in your L20B build then your compression will be 10.11

 

 

Compression.

Assuming there is no detonation caused by compression, higher is always more efficient than lower. For one, the burn time is much reduced so less heat is lost to the combustion chamber, piston and cylinder walls and can be used to move the piston. The resultant explosion exerts more pressure on the piston at or near the top of it's travel.

 

Pour a cup of gas on the ground and light it and poof it just burns, but contain it inside a room and it shorten it's burn time and will blow the roof off. An 8 oz cup of gas contains the equivalent of  7.5 pounds of TNT, about 15, 1/2 pound sticks.

[flatcat19]

Turning Ratsun to anarchist.com?

[nl320what]

From my Archives:

 

Short Rod L16
This is my current low compression L16 for turbo use.
7.8:1 CR using 37cc cylinder head.

Lowering compression of a L16 would be easier by just installing a open chambered L20B head and using stock bottom end.

I just wanted to utilize a good 37cc head I already had.
parts: L16 crank, L18 rods, L24 (flattop) pistons, L16 block.
s/2+r+p: 205.2mm
piston deck height: -2.70mm (below deck)

 

or

 

Turbo 2.2L

7.87:1 Compression ratio with 45.2cc open chambered head.
Parts: Z22 crank, 2.2E pistons, Z22S/L20B rods in Z22block or Z20/L20B block bored +2mm,
s/2+r+p: 224.4
piston deck height: -3.45 (below block)

[datzenmike]

Never understood low compression turbo engines. If not boosting it's a 7.8 compression running dog.  

[Josh K.]

And when boosting it's a scalded dog... Just sayin...

[datzenmike]

Again for use on the street just how much time is spent 'boostin'??? Maybe racing, but for easy startups and urban driving, stop and go I see no advantage in a sluggish car.

[Josh K.]

Sluggish? Not sure what boosted cars you've driven. This ain't the 80's.

[datzenmike]

Said when not boosting twice.

[Draker]

Subaru WRX has a compression ratio of 8.0:1, and it's not sluggish by any means. No startup or run-ability issues... now, it's not 7.8:1 but that's not far off.

[Josh K.]

Said when not boosting twice.

Yeah, I can read. Sluggish turbo cars were eliminated in the 80's.

 

I have a 2.0L turbo in my Malibu. Can't even tell it has a turbo.

[nl320what]

Flat tops with L20b rods. Lower compression would make it better for mpg?

 

What are you driving around as far as motor right now?  I seen a post about a motor being in the shop also, whats the build specs on it?

[That4doorKiD]

My 510 isn't being driven as of now. It's just sitting on the street with the l-16 still in it. Took off my blowthrough set up so I can sell it and get money for my new set up.

 

L20b bored .030 over, will be .040 soon when I go back.

 

Datzenmike,

You said L20b rod combo with SR20 flat tops 32mm pin height would be 8.1:1 compression not 6:1

[That4doorKiD]

8.55 to be exact

[datzenmike]

Sluggish? Not sure what boosted cars you've driven. This ain't the 80's.

 

 

Yeah, I can read. Sluggish turbo cars were eliminated in the 80's.

 

I have a 2.0L turbo in my Malibu. Can't even tell it has a turbo.

 

Didn't say turbo cars were sluggish.... said low compression engines were sluggish when not boosting, which is most of the time, and these aren't '80 or newer engines either. They are not EFI nor exotic mixture control and  ignition retard. They are for the most part home made. Tell me, does your Mallabu have a 6.5 compression ratio???? It doesn't because it would be an absolute dog to drive.

 

 

 

Datzenmike,

You said L20b rod combo with SR20 flat tops 32mm pin height would be 8.1:1 compression not 6:1

 

8.55 to be exact

 

 

I looked and couldn't find that quote. But I did find these for SR flattops and SR 12cc dish on 152.5mm rods, SR flattops on L20B rods and L28 flattops on L20B rods. No mention of 8.1 or 8.55 compression.

 

 

 

 

L20b bored to 86mm

152.5mm Z20E rods

SR20 32mm pin height pistons 12cc dish modified (bushed) to take Z20E pin

 

 L20B block is 227.45mm tall

152.5 + 32 + (1/2 86mm stroke) 43mm = 227.5mm

 

Piston is 0.05mm above deck

Compression is 10.57 if flattop

Compression is 8.71 if 12cc dish.

 

 

 

Flattop what???? SR20 pistons???? With L20B rods??? I already explained what will happen with this combo. From crank center line to top of block is 227.45mm. Half the stroke is 43mm so 184.45mm left. SR20 pin height is 32mm so 152.45mm left. If you run an L20B rod which is 145.9 mm long you will have 6.55mm of cylinder space left that is not being used. This volume, 6.55mm x 86mm diameter, is 38 extra ccs added to the 45.2 combustion chamber plus the gasket volume of 6.9cc. Your combustion chamber is now 90.1cc. An 86 x 86 B&S cylinder is 499cc and your compression will be 6.5. This is so pathetic a compression it will just barely idle.

 

If you have changed your mind about the 152.5mm rods and SR20 pistons and mean 86mm flatops from an L28 in your L20B build then your compression will be 10.11