Domed pistons
The catalog says 11/1 with 64cc heads.What they don't say is that at 3.930 bore, to get 11/1 requires a total chamber volume of 65.896cc.
The cd on those 299s is 1.81, so from the piston top to the deck, not including the dome, will be ~ .0095 if the deck is 9.600;
that's 1.9cc.
the dome is -6cc
gasket (.039) is 8.8cc
and the heads could be up to 72cc for smog heads.
Total estimate is 76.7, and if correct, that will be 9.59Scr
To get to 11, the heads would have to be 61.2cc
But hang on, that's a mighty big cam for a 318, and the Ica is 80* Installed at +4, assuming an LSA of 110. And with just 11/1 Scr, the pressure is predicted to be just 149psi @500ft elevation, and the low rpm performance will be pretty doggie. It's a good thing you chose 4.10s.
Furthermore, the powerpeak of that cam is gonna be up around 5600 rpm or so. Is that what you figured? Is that what you want?
IIRC the NV4500 has ratios of 3.49-2.14-1.38-1.00-.73od Those are pretty good, but the splits are ; .61-.645-.725-.73
That means that whatever you rev your engine to, the Rs will fall to those percents at the shifts. So lets say you choose a shift of 5800. then the rpms will drop to: 3540-3740-4200-4230
With a power peak of 5600, the torque peak is likely to come in at around 4300, so for low ET, you need your drops to come in around there or higher on every shift. But the first two shifts are way off the mark. and by top of third when she finally drops in on the cam, your speed is already 85mph, and now you gotta buck the wind.with a somewhat lazy combo (irrespective now of the 4.10s, which can't help anymore.)
So what's wrong?
Well firstly; those pistons are a great choice. IDK what your head-chamber CCs will come in at, but this combo can make almost any chambers work.
But I don't like that cam; it is just too big. You need a cam to match the powerband dictated by the transmission. and a rearend to put the power where yo need it to be. While 4.10 x.73= 2.99 cruiser gear, those 4.10s are the wrong rear for at least the first two gears.
For a streeter, 3.55s are what you want; here's why; 3.55s will get you 60 mph revving 5500 in 2.14 second gear with 28" tires. So you got a bit of rpm left over. Shifting at 5500 means your powerpeak can be around 5200, and that dictates a cam of around [email protected] or 268 to 276 advertised, on a hydro. This is still plenty big for a 318 so lets make it a solid lifter cam of 268* at .012 valve lift after lashing. And lets make it on a 112 to cover that powerband. So in at 112* I get an Ica of 66*, and now your pressure at 11/1 jumps up to 177psi which is too much for iron heads, but at 9.59 is back to 148, but now with a much stronger bottom end.
But lets get it up to 8.0Dcr; with an Scr of 10.2, and Ica of 66*, the math spits out 160 psi, to run best pumpgas at WOT. This is the best bottom end you will get on this combo, and it is over 30% stronger than the Howards cam at 11/1.
But to be clear, the 230 cam will not make the absolute power that the Howards 248 will. But I can guarantee you that the 230*cam will be WAAAAAAAAAY more fun to drive, and will probably get you to 60 mph quicker.
So how to get to 10.2 should be your next question.
At 3.93 x3.315 the required total chamber volume is no more than 71.62cc.
Subtracting 1.89 -6 +8.8=4.7, leaves 66.92cc for the heads. How easy is that.
Hang on, we're not done yet. You the piston fitter, have to make sure those 299s actually fit in the chambers without hitting anything. And if you have to machine them, then the math goes off; your head chambers will have to be adjusted for that.
BTW,
>I like your idea of not decking the block, so long as it measures useable as-is.. and so long as the 299s are not too much deeper in the holes than the math indicates. If I was building a 318, I think I would give those a try, even if I had to mill them to fit.
>I tried the .028 Gaskets but they squeezed out on me (alloy heads); others say they are fine.
> I have had no trouble with the FelPro .039s, at up to 185psi, ( the highest I have run).
> In my streeter, I have run a [email protected] cam in my 367 (at over 185psi), and I couldn't wait to get rid of it. I replaced it right away with a 223/230/110 and absolutely loved it. When that 223 gave up, I replaced it, with a 230/237/110 and was immediately disappointed. She gave up a lotta bottom-end, and I had to really scramble to get it back. My solution was a lower gear in the trans, and a lot of tuning; but really, the shine was off the apple. I am waiting for it to die, so I can replace it, but since 2004 it just keeps on going, and going, and going...
Oh yeah, just a reminder, my gearing math was based on 28" tires, and the transmission ratios are from memory............ so you know; garbage in garbage out; but the points are the same ;
1) IMO that Howards is way too much for a street 318, and
2) IMO you need to better match your cam to whatever the gear splits that your NV4500 actually has.and
3) manual transmissions are way more fussy than automatics, cuz the tires are married to the engine by the clutch; there is no torque-multiplying fluid-coupler to help.
4) to be clear, the NV 4500 ratios, if I remember them right, are great for DRAGRACING. And the 3-4 split is great as well. But the first two splits are set up for a low-rpm small engine making lots of torque....... like a 5.2Magnum; which has a well-matched cam, and tuning that you cannot duplicate with an LA, unless maybe you put a tunnel-ram on it,lol. Or maybe a turbo.......
The catalog says 11/1 with 64cc heads.What they don't say is that at 3.930 bore, to get 11/1 requires a total chamber volume of 65.896cc.
The cd on those 299s is 1.81, so from the piston top to the deck, not including the dome, will be ~ .0095 if the deck is 9.600;
that's 1.9cc.
the dome is -6cc
gasket (.039) is 8.8cc
and the heads could be up to 72cc for smog heads.
Total estimate is 76.7, and if correct, that will be 9.59Scr
To get to 11, the heads would have to be 61.2cc
But hang on, that's a mighty big cam for a 318, and the Ica is 80* Installed at +4, assuming an LSA of 110. And with just 11/1 Scr, the pressure is predicted to be just 149psi @500ft elevation, and the low rpm performance will be pretty doggie. It's a good thing you chose 4.10s.
Furthermore, the powerpeak of that cam is gonna be up around 5600 rpm or so. Is that what you figured? Is that what you want?
IIRC the NV4500 has ratios of 3.49-2.14-1.38-1.00-.73od Those are pretty good, but the splits are ; .61-.645-.725-.73
That means that whatever you rev your engine to, the Rs will fall to those percents at the shifts. So lets say you choose a shift of 5800. then the rpms will drop to: 3540-3740-4200-4230
With a power peak of 5600, the torque peak is likely to come in at around 4300, so for low ET, you need your drops to come in around there or higher on every shift. But the first two shifts are way off the mark. and by top of third when she finally drops in on the cam, your speed is already 85mph, and now you gotta buck the wind.with a somewhat lazy combo (irrespective now of the 4.10s, which can't help anymore.)
So what's wrong?
Well firstly; those pistons are a great choice. IDK what your head-chamber CCs will come in at, but this combo can make almost any chambers work.
But I don't like that cam; it is just too big. You need a cam to match the powerband dictated by the transmission. and a rearend to put the power where yo need it to be. While 4.10 x.73= 2.99 cruiser gear, those 4.10s are the wrong rear for at least the first two gears.
For a streeter, 3.55s are what you want; here's why; 3.55s will get you 60 mph revving 5500 in 2.14 second gear with 28" tires. So you got a bit of rpm left over. Shifting at 5500 means your powerpeak can be around 5200, and that dictates a cam of around [email protected] or 268 to 276 advertised, on a hydro. This is still plenty big for a 318 so lets make it a solid lifter cam of 268* at .012 valve lift after lashing. And lets make it on a 112 to cover that powerband. So in at 112* I get an Ica of 66*, and now your pressure at 11/1 jumps up to 177psi which is too much for iron heads, but at 9.59 is back to 148, but now with a much stronger bottom end.
But lets get it up to 8.0Dcr; with an Scr of 10.2, and Ica of 66*, the math spits out 160 psi, to run best pumpgas at WOT. This is the best bottom end you will get on this combo, and it is over 30% stronger than the Howards cam at 11/1.
But to be clear, the 230 cam will not make the absolute power that the Howards 248 will. But I can guarantee you that the 230*cam will be WAAAAAAAAAY more fun to drive, and will probably get you to 60 mph quicker.
So how to get to 10.2 should be your next question.
At 3.93 x3.315 the required total chamber volume is no more than 71.62cc.
Subtracting 1.89 -6 +8.8=4.7, leaves 66.92cc for the heads. How easy is that.
Hang on, we're not done yet. You the piston fitter, have to make sure those 299s actually fit in the chambers without hitting anything. And if you have to machine them, then the math goes off; your head chambers will have to be adjusted for that.
BTW,
>I like your idea of not decking the block, so long as it measures useable as-is.. and so long as the 299s are not too much deeper in the holes than the math indicates. If I was building a 318, I think I would give those a try, even if I had to mill them to fit.
>I tried the .028 Gaskets but they squeezed out on me (alloy heads); others say they are fine.
> I have had no trouble with the FelPro .039s, at up to 185psi, ( the highest I have run).
> In my streeter, I have run a [email protected] cam in my 367 (at over 185psi), and I couldn't wait to get rid of it. I replaced it right away with a 223/230/110 and absolutely loved it. When that 223 gave up, I replaced it, with a 230/237/110 and was immediately disappointed. She gave up a lotta bottom-end, and I had to really scramble to get it back. My solution was a lower gear in the trans, and a lot of tuning; but really, the shine was off the apple. I am waiting for it to die, so I can replace it, but since 2004 it just keeps on going, and going, and going...
Oh yeah, just a reminder, my gearing math was based on 28" tires, and the transmission ratios are from memory............ so you know; garbage in garbage out; but the points are the same ;
1) IMO that Howards is way too much for a street 318, and
2) IMO you need to better match your cam to whatever the gear splits that your NV4500 actually has.and
3) manual transmissions are way more fussy than automatics, cuz the tires are married to the engine by the clutch; there is no torque-multiplying fluid-coupler to help.
4) to be clear, the NV 4500 ratios, if I remember them right, are great for DRAGRACING. And the 3-4 split is great as well. But the first two splits are set up for a low-rpm small engine making lots of torque....... like a 5.2Magnum; which has a well-matched cam, and tuning that you cannot duplicate with an LA, unless maybe you put a tunnel-ram on it,lol. Or maybe a turbo.......
