ECUtune Camshafts

[TomsSVX]

Glad to hear you are jumping on board

Tom

[sicksubie]

Well... I trust you guys and just because I am getting them does not mean they will be going in any time soon.










Yeah right, once they have been on the bench for a week I will be dying to get them in

[sicksubie]

Also, I don't know if I have to make this clear before I order but the plan is to go stage 3 with this car.

[cdigerlando]

Originally Posted by sicksubie

Also, I don't know if I have to make this clear before I order but the plan is to go stage 3 with this car.

Don't forget, we are all going where no man has gone before. I hope its worth it. I think we are following all of the conventional logical steps to achieve our goals. I'm sure it will not be without its bumps.

[cdigerlando]

Originally Posted by longassname

there is no total cost yet

The only thing we have an exact price on yet is the rods $575 + $10 shipping
Tomorrow we will probably have an exact price on the pistons...we're expecting $970 but I'm not locking myself into that price until the distributor locks in their price with us.
We are still weeks away from having an exact price on the cam, valve, valvespring set price.

I'm in for pistons as well. Do you need my shipping info for the rods, or did I already give you that?

[sicksubie]

ordered

[jman050]

what sort of rpm would this valvetrain be able to handle assuming headflow is not the limiting factor?

[longassname]

I'll think about it again when I'm standing over the short in the shop but I don't know...looking at that picture and going back and looking at my pictures it looks awfully stout. Maybe just step the surfacing of the deck...take 1 thousandth off of the outer so the pressure on the gasket around the cyllinders increases.

Originally Posted by TomsSVX

hey mike... wanted to make sure you got the payment. i sent it last night... should be for the pistons and rods. Also I wanted to put this pic of the block up so you could get a better idea of the deck plates



tom

[cdigerlando]

Mike:

Are you making the deck plates too or are we looking for someone to do them?

My thought on plates were to weld the plates in place, then mill a thousandth off to mill off the welds, and clean up the surface. I don't know if this would require a second time through on the welds and milling. Or maybe a shallow first pass, clean up the welds then do a second pass taking a thousandth off. Then add it back on the copper head gasket. I guess it depends on how well the welding is done. Your idea of leaving the sleaves a little higher might work to seal the cylinders in a bit tighter, but it might be tough with the plates in place. It might have an effect like o-ringing though, and could work well with the open deck.

[longassname]

What i was saying is I'm not sure we need inserts at all. If I make them (which means do the cad drawings and have someone else cnc them) I will just press them in not weld them. I'm thinking it looks awfully stout as is though. I might prefer just to take 1 thousands off the outer parts of the deck and leave it open.

also...by the by...time to get your piston order in

Originally Posted by cdigerlando

Mike:

Are you making the deck plates too or are we looking for someone to do them?

My thought on plates were to weld the plates in place, then mill a thousandth off to mill off the welds, and clean up the surface. I don't know if this would require a second time through on the welds and milling. Or maybe a shallow first pass, clean up the welds then do a second pass taking a thousandth off. Then add it back on the copper head gasket. I guess it depends on how well the welding is done. Your idea of leaving the sleaves a little higher might work to seal the cylinders in a bit tighter, but it might be tough with the plates in place. It might have an effect like o-ringing though, and could work well with the open deck.

[Trevor]

Originally Posted by longassname

What i was saying is I'm not sure we need inserts at all. If I make them (which means do the cad drawings and have someone else cnc them) I will just press them in not weld them. I'm thinking it looks awfully stout as is though. I might prefer just to take 1 thousands off the outer parts of the deck and leave it open.

also...by the by...time to get your piston order in

It would appear that you are somewhat undecided, so other opinion may be welcome.

IMHO leave as is, as you are suggesting. Welding will create unknown and unwanted stresses. Pressed in inserts will do the same as it will be impossible to estimate deflections when heat is applied and all is operational. Also take into account that pressed in items can only offer support in compression.

Creating extra pressure around the bores is certainly a worthwhile idea. Edit P.S. Depending on the head gasket material, the added hight could be greater than what you suggest. After all there is little internal pressure exerted in other areas by comparison, and possible leaks of less consequence.

As you have commented, overall things do look adequate and you can accept that considerable over engineering can be expected with a production product.

[TomsSVX]

thats what I was thinking when I looked at my block when I seperated the block. they are very stout to begin with and it may overkill to improve upon it

Tom

[longassname]

It sounds like you are asking about where torque starts dropping off rather than when stuff starts flying appart. The answer to that is it depends on how big a charge you are stuffing into your cyllinders.

As I began explaining earlier the first constraint we run into in a 4 stroke engine is clearing the cyllinders of the exhaust gasses so we aren't pumping the plug out with the piston and contaminating our intake charge making our ignition timing go wacky. The longer the duration and the closer the center to optimum on the exhaust cam the higher the rpm we can run before we run into that constraint. As you raise boost pressure and force a larger intake charge into the cyllinders the lower the rpm you run into that constraint.

The camset I am putting together uses a larger exhaust cam than intake cam just like they did factory. Our seat to seat durations on both cams are chosen to be as long as possible without any significant loss of low end power. If you increased duration, all else equal, there would be a trade off in low rpm torque and power but there are things we can do to maintain low rpm performance. By increasing lift and using progressive rate ramps we are able to maintain low rpm performance reducing our give and increasing our take in the trade off. Our new happy points for seat to seat duration come out to be 256 intake and 264 exhaust. This substantially raises the rpm at which our torque peaks, keeps our torque substantially higher throughout most of the rpm band, and has only a minimal torque torque loss at the lowest rpms where we would rather not be snapping our axles etc anyway.

Originally Posted by jman050

what sort of rpm would this valvetrain be able to handle assuming headflow is not the limiting factor?

[Trevor]

Originally Posted by longassname

It sounds like you are asking about where torque starts dropping off rather than when stuff starts flying appart. The answer to that is it depends on how big a charge you are stuffing into your cyllinders.

As I began explaining earlier the first constraint we run into in a 4 stroke engine is clearing the cyllinders of the exhaust gasses so we aren't pumping the plug out with the piston and contaminating our intake charge making our ignition timing go wacky. The longer the duration and the closer the center to optimum on the exhaust cam the higher the rpm we can run before we run into that constraint. As you raise boost pressure and force a larger intake charge into the cyllinders the lower the rpm you run into that constraint.

The camset I am putting together uses a larger exhaust cam than intake cam just like they did factory. Our seat to seat durations on both cams are chosen to be as long as possible without any significant loss of low end power. If you increased duration, all else equal, there would be a trade off in low rpm torque and power but there are things we can do to maintain low rpm performance. By increasing lift and using progressive rate ramps we are able to maintain low rpm performance reducing our give and increasing our take in the trade off. Our new happy points for seat to seat duration come out to be 256 intake and 264 exhaust. This substantially raises the rpm at which our torque peaks, keeps our torque substantially higher throughout most of the rpm band, and has only a minimal torque torque loss at the lowest rpms where we would rather not be snapping our axles etc anyway.

As many will probably be aware, I have previously entered into what turned into argument, regarding proposed camshaft modifications. Many of the facts stated were stupid, as were many comments. Previous attempts had proved largely fruitless and were not based on sound logic.

The above summary indicates that at long last, the issue has been properly considered with due expertise and a logical design the result. Success can well be anticipated.

[cdigerlando]

Pressed in inserts are not the way to go. They are prestressed, and when everything starts heating up the cyliders can neck down at the top. Welding is the only way to go. Yes it's probably overkill. Isn't that the idea?

Mike did you get my piston payment OK?