2.3l or 2.4l

[BoostKrazy]

I have a 97 gsx that i want to make into a torque monster.
I have a freshly pulled 7 bolt 4g63 sitting in my backyard on the engine stand that i just disassembled tonight. The crank looks to be in good shape. I also have a set of brand new Manley rods that are still in the box. Now my question is, should i sell the manley rods, keep the 4g63 crank and go longer rods for a 2.3l, or find a 4g64 crank and use my manley rods for a 2.4l? I havent bought pistons yet, and idk if im going to be boring the block yet also. Kind of new to strokers so im just looking for insight before i take the block to get machined.

Thanks

 

[WES_393]

The 2.3 doesn't use longer rods. The 2.0, 2.3, and 2.4 all use the same length rods. The 2.3 uses a 4g63 block, 4g64 crank, and 6mm shorter 4g63 pistons. The 2.4 is a 4g64 block, crank, and pistons (86.5-87mm 4g63 pistons) with a 4g63 head.

 

[HIGHPSI4]

The 2.4 is a 4g64 block, crank, and pistons (86.5-87mm 4g63 pistons) with a 4g63 head.

Good info. The 2.4 uses 2.4 pistons and the stock bore is 86.5mm. I know what you ment, just wanted to help clear up the piston info.

 

[killercolt]

I like this combo the best.
2.4 4g64 block
100mm crank
Eagle or better rods
2.0l 86.5mm 11:1 wiseco hd pistons (will give you 265psi of compression)
.005" ptw clearance
Kelford 272 cams
1mm oversize valve
Jmf race manifold
Gt4088r
E85

I have seen this combo in person make over 600hp/500tq at 20psi and over 700hp and 600tq at 28psi. This combo will give you the nastiest tq number you will see for the boost level.

 

[arrowhead]

I like this combo the best.
2.4 4g64 block
100mm crank
Eagle or better rods
2.0l 86.5mm 11:1 wiseco hd pistons (will give you 265psi of compression)
.005" ptw clearance
Kelford 272 cams
1mm oversize valve
Jmf race manifold
Gt4088r
E85

I have seen this combo in person make over 600hp/500tq at 20psi and over 700hp and 600tq at 28psi. This combo will give you the nastiest tq number you will see for the boost level.

Do you mean 2.3 stroker pistons or regular 2.0 piston?
If 2.0 would not the pin be in wrong location, please clarify, never heard of this combo.

 

[WES_393]

No, he means 4g63 pistons.

The 4g64 uses a 100mm crank while the 4g63 uses an 88mm crank. The 4g64 block is also 6mm taller in order to compensate for the extra 12mm of throw, it doesn't use shorter pistons. Since the 2.3 is a 4g64 100mm crank stuffed into a 4g63 block meant for only 88mm, you need to make up for the shorter deck height which is usually done by using shorter pistons. So when using a 4g64 block and crank, you can use "4g63" pistons. They just need to be the right bore size. The advertised compression ratio is the only difference between an "86.5mm 4g63" piston and a "standard size 4g64" piston.

Since piston manufacturers have a limited selection of standard options for both engines, you can use that change in compression to your advantage. For example, 10:1 is the highest compression "4g64" piston Manley offers. However, they also offer 10:1 "4g63" pistons up to 87mm in size. But if used in a 4g64, they would actually have 11:1 compression.

 

[arrowhead]

I understand perfectly, I just miss out on the 2.4 crank and block. Since the OP never mentioned having a 2.4 block.

 

[GPTourer]

The 2.0, 2.3, and 2.4 all use the same length rods.

What else changes to make one of the "long-rod" 2.4 strokers some shops tout? Just piston height? I know these are better for revving and are more square (and more costly.)

 

[HIGHPSI4]

No, he means 4g63 pistons.

The 4g64 uses a 100mm crank while the 4g63 uses an 88mm crank. The 4g64 block is also 6mm taller in order to compensate for the extra 12mm of throw, it doesn't use shorter pistons. Since the 2.3 is a 4g64 100mm crank stuffed into a 4g63 block meant for only 88mm, you need to make up for the shorter deck height which is usually done by using shorter pistons. So when using a 4g64 block and crank, you can use "4g63" pistons. They just need to be the right bore size. The advertised compression ratio is the only difference between an "86.5mm 4g63" piston and a "standard size 4g64" piston.

Since piston manufacturers have a limited selection of standard options for both engines, you can use that change in compression to your advantage. For example, 10:1 is the highest compression "4g64" piston Manley offers. However, they also offer 10:1 "4g63" pistons up to 87mm in size. But if used in a 4g64, they would actually have 11:1 compression.

How does using the 63 piston in a 64 bump up the compression ratio? Is it piston design?

 

[WES_393]

What else changes to make one of the "long-rod" 2.4 strokers some shops tout? Just piston height? I know these are better for revving and are more square (and more costly.)

Yes, piston height (aka compression height) is the only way to increase rod length without affecting engine size. The standard and LR 2.4 both use 100mm crankshafts and 86.5mm bore. But the standard 2.4 has 150mm rods and 1.375" compression height while the LR has 156mm rods and 1.130" compression height. You could further increase that rod length to 162mm by using an 88mm crank, but that changes your Long Rod 2.4 into a 2.1 Destroker.

 

[GPTourer]

Yeah, the 2.1L destroker was always intriguing to me for a FWD because I'd rather have revs then more torque and have killer top end on a laggier turbo. But then I start thinking about the expense vs just a well built 2.0 and I'm not sure it would be worth it.

 

[WES_393]

How does using the 63 piston in a 64 bump up the compression ratio? Is it piston design?

The difference in compression comes from the difference in cylinder volume. Piston design is actually the constant here. Compression ratio is the cylinder's maximum volume (at BDC) and minimum volume (at TDC). If the max volume is 10cc and the min is 2cc, then your compression ratio is 10:2, or 5:1 simplified. But with a max volume of 20cc and the same min volume of 2cc, the compression ratio has been increased to 20:2, or 10:1.

So when you have two engines that have an equal minimum volume (same piston design and head volume) but different maximum volume (stroke), you get a higher compression ratio. Your squishing more stuff into the same space.