cutting the deck
cutting the deck
I currently have my 2.0 block at the machine shop. Having it bored .040 for the dohc pistons I got. And I was also going to get him to cut the deck. Just wondering how much could he cut off the deck before I run into piston to valve clearance.and about how much would he have to cut off to get it to 11 to 1 compression . I'm going to clay it before the final assembly just to make sure it has the right clearance.
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What head are you using? SOHC or DOHC?
Just asking, but assuming you are SOHC/stock spec DOHC pistons, then Dranz's advice is pretty well on the mark.
The added bore will raise the CR a little too. If they are 10.5:1 for a DOHC head, and you are using a SOHC head, then you will be nearly at 11:1 without shaving anything.
I may be wrong, but I can't see a major gain between 10.5+ and 11:1.
Stock DOHC pistons with a SOHC head will net you ~10.3. You will need to massage the head chamber, or the pistons to keep contact from happening, especially with the larger bore. The head is the preferred method. The larger bore may automatically get you close to 10.5, assuming stock type replacements.
Just asking, but assuming you are SOHC/stock spec DOHC pistons, then Dranz's advice is pretty well on the mark.
The added bore will raise the CR a little too. If they are 10.5:1 for a DOHC head, and you are using a SOHC head, then you will be nearly at 11:1 without shaving anything.
I may be wrong, but I can't see a major gain between 10.5+ and 11:1.
Stock DOHC pistons with a SOHC head will net you ~10.3. You will need to massage the head chamber, or the pistons to keep contact from happening, especially with the larger bore. The head is the preferred method. The larger bore may automatically get you close to 10.5, assuming stock type replacements.
Bill
1999 neon coupe 2.4 swap
2021 Forester
2000 Neon MTX swap with '02 R/T PCMOlha Koba, a psychologist in Kyiv, said that “anger and hate in this situation is a normal reaction and important to validate.” But it is important to channel it into something useful, she said, such as making incendiary bombs out of empty bottles.
1999 neon coupe 2.4 swap
2021 Forester
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- Junior Admin
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10.3 - 10.5 will be plenty for that cam. There is no valve overlap, so going higher than that will only create issues. You should be able to use the stock PCM or a reprogrammed unit and still pass emissions.
Bill
1999 neon coupe 2.4 swap
2021 Forester
2000 Neon MTX swap with '02 R/T PCMOlha Koba, a psychologist in Kyiv, said that “anger and hate in this situation is a normal reaction and important to validate.” But it is important to channel it into something useful, she said, such as making incendiary bombs out of empty bottles.
1999 neon coupe 2.4 swap
2021 Forester
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- Junior Admin
- Posts: 20312
- Joined: Thu May 03, 2007 12:14 pm
- Location: Ashland Ohio
Should be good. Possibly even with 87, the PCM will just pull the timing back.
Our '96 runs fine on 87, stock cam, ported head, 10.3:1. You can always try it with a few gallons, if it pings, fill the rest with 93, or add some E85.
Our '96 runs fine on 87, stock cam, ported head, 10.3:1. You can always try it with a few gallons, if it pings, fill the rest with 93, or add some E85.
Bill
1999 neon coupe 2.4 swap
2021 Forester
2000 Neon MTX swap with '02 R/T PCMOlha Koba, a psychologist in Kyiv, said that “anger and hate in this situation is a normal reaction and important to validate.” But it is important to channel it into something useful, she said, such as making incendiary bombs out of empty bottles.
1999 neon coupe 2.4 swap
2021 Forester
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- Junior Admin
- Posts: 20312
- Joined: Thu May 03, 2007 12:14 pm
- Location: Ashland Ohio
What you need to consider is dynamic compression. With a zero overlap cam, there is nothing bleeding off pressure. Once you get some rpm up, the cylinder pressures might be too high for even the base lowest spark map to keep it from pinging.
Even back in the sixties when there was real gasoline, Pontiac had a factory ~11:1 engine. But they cammed it very big so it could still run on street gas. It didn't make real cylinder pressure until it was up there in RPM.
To run over 10.5:1, you are going to need a bigger cam than a 400. And anything bigger than a 400 needs at minimum, a piggy back control for fuel, etc. You are now beginning to add probably more cost than you want, for the power gained.
IMHO, if you are getting into the need for engine management to make power, you may as well spend for boost. Because there, you are going to get a better return on your investment.
It will be a substantially higher investment, but so will the power gains. And driveability.
Even back in the sixties when there was real gasoline, Pontiac had a factory ~11:1 engine. But they cammed it very big so it could still run on street gas. It didn't make real cylinder pressure until it was up there in RPM.
To run over 10.5:1, you are going to need a bigger cam than a 400. And anything bigger than a 400 needs at minimum, a piggy back control for fuel, etc. You are now beginning to add probably more cost than you want, for the power gained.
IMHO, if you are getting into the need for engine management to make power, you may as well spend for boost. Because there, you are going to get a better return on your investment.
It will be a substantially higher investment, but so will the power gains. And driveability.
Bill
1999 neon coupe 2.4 swap
2021 Forester
2000 Neon MTX swap with '02 R/T PCMOlha Koba, a psychologist in Kyiv, said that “anger and hate in this situation is a normal reaction and important to validate.” But it is important to channel it into something useful, she said, such as making incendiary bombs out of empty bottles.
1999 neon coupe 2.4 swap
2021 Forester