And north side of 400hp.
Good idea on lift bomber.
Duration is the power and and I don't know what ratio you will end up at or the tires size.
That would be what?
Added 2 cents on a cam. Something like this: Hughes Engines
Last edited:
Need Help on Magnum 360/380 hp Crate Motor Tech Info
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Good idea on lift bomber.
Duration is the power and and I don't know what ratio you will end up at or the tires size.
That would be what?
Added 2 cents on a cam. Something like this: Hughes Engines
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Yeah, I see I missed a few posts, so sorry. Rumble woke me up.
But I think the guys got you covered, I'm gonna go lick my wounds.
But just to reiterate, almost any performance cam you choose will want a higher stall TC and gears to recover the out of gate performance lost by that cam.
So in my thinking I would upgrade the TC and gears first, to be ready for the cam. If you don't already know this, every cam size will move the operating characteristics up about 200 rpm. So going from say [email protected] to 220@ .050 is about 3.5 cam sizes, and so the power peak rises about 700 rpm. And so does the torque peak. And so does the off-idle torque. Power takes rpm,for the most part. So a cam is always trading away low-rpm power/torque for hi-rpm power/torque. Normally aspirated,that's just the way it works. Eventually you have an engine that pulls super hard from say 5500 to 7000, but needs all kinds of help below 3000rpm.And the powerband becomes more and more focused.
So in a streeter,with a small engine, it is all-too-easy to get carried away with too much cam. And if the cylinder pressure does not keep pace, disaster is lurking at the results.
Then you have the gearing issue. Say you had an operating range of 1000 to 4500 like maybe a stocker. That's 3500rpm operating range. So revved right out with 2.76s you might have shift speeds of 52/87/and127mph.
But with a big cam, the operating rpm might realistically be from 3000 to 7000, and revved right out, the shift speeds might be 80/136 and197mph, with those same 2.76s. Well one of those is pretty useless, and second ain't much better. At the other end, this cam would need a huge TC to get moving reasonably well cuz of the bottom-end torque loss.
So what do you do? You re-gear it to fit your driving application. Maybe you are a racer and are looking for 120 in the qtr, so you might put 4.56s in it, and a 4500TC. BUt that's not gonna fly for a streeter. 3.55s are the go-to for a streeter allowing some semblance of hiway operation. Well that's still not gonna fly cuz first gear is good to 65 mph, and the crazy TC while being a real hoot, is not the best thing since the invention of sliced bread. So it has to come out, and immediately the soft bottom end becomes apparent.
So what to do?
Middle of the road is what to do. Sacrifices and adjustments to fit everything into the budget, and to fit your driving requirements, and to fit the engines ability to absorb a bigger cam with a lowered cylinder pressure. In other words how much low-speed torque,driveability, fuel economy, etc; are you willing to give up?
So if you didn't already know this; now you do.
I can tell you that I did not like the 292/108 cam in my 360LA with 3.55s. No way! Lots of top-end power, a great midrange rush, but even with 11.3 Scr. the bottom end was just too soft.And of course there was the speed thing mismatch remaining. First gear was good to over 60mph. I tried several rear ratios before settling on 4.30s, to get some kind of bottom end torque back.That's an example of too big. And I had lots of cylinder pressure, that's the thing. I got rid of that cam in a hurry.
Having had too-big, I now had a pretty good idea of what I didn't want. So I got me a 270/110 fast-rate cam.And I reduced the Scr to 10.9. Now that was a real nice DD cam. But of course it was soft on top now. So again I experimented with gearage. Lots and lots and lots of gearage. In the end I learned that once you get into a gear that you want to trap with, it don't matter how many more gears you have. And once you are in that gear, the only thing that counts is power. If your engine is too small, or the cam is out of breath,or the heads are choked, disappointment is right there.
So after about 4 years that cam began dropping lobes, and out it came. So I phoned Hughes, and told them of my plight, and what cam I might be happy with. Turns out they wanted to sell me another big cam. I said no,been there done that. So I got me the current 276/110 cam. I gave up some low-speed torque for sure, but I got some serious top end back. Middle of the road.And I was able to give up all that gearage for something a lil more sane.
So no, I am not recommending that you run out to get a 276/110. Remember, I'm making over 180psi cylinder pressure. How much are you making? See, that's the limiting factor. Too much pressure and the engine wants to self-destruct. Too little and things get soft in a hurry. The cam just sets the operating range, and the published numbers are little more than guidelines.
Your target with iron heads is about 165 psi. That's where the power is. And detonation can be right close to that, with open chamber no-swirl/no Quench heads.
100psi makes a dog of an engine, You'll need a lot of help to get off the line.
120 is still very soft, you'll need a Big TC and gears to get happy
140 is sorta acceptable with a hi-stall, and 3.55s
150/155 is where things start to gel for a streeter
165 may be the upper limit for iron heads and pumpgas.
170 has been posted as doable with some good combos.
185 requires a change to aluminum heads
195 requires aluminum and tight-Q. I ran this for a short while, with no evidence of detonation.
205 and up is sorta off limits, but there are a few fellows on FABO that say they have been able to make it work.
So this would be your after new cam is installed targets. If you are already at below 150, forget a bigger cam, unless you are prepared to cough up more money for a TC and gears. The stock 252cam in a 9.0 360 might make 150 psi when new. Each bigger cam might drop the pressure 2 to 4 psi, depending on what the LSA is doing. But the VP index which indicates what the engine feels like in the bottom end can change over 8 numbers per cam size and that's a lot! What that means is that even tho going from the 252/112 stock cam to a 273/110 cam the pressure might only drop 10 psi; the V/P might drop twice that, turning a strong stock bottom end into a weiner.
My engine has a V/P of 153 and has a dynomite bottom end now.
Your 5.9 stock might be 142. With a 273/110 that might drop to 123. An 8.0 slanty might have 118. Get it 118 to 123. Don't go down there
If you put a teener cam in that 5.9, the V/P might jump from 142 to 145, just to give you an idea.
A 10/1- 400 might have the same V/P as do I,namely 153
V/P is very useful to understand why a strong engine turns into a weiner after a cam install.
See it here;
V/P Index Calculation
But I think the guys got you covered, I'm gonna go lick my wounds.
But just to reiterate, almost any performance cam you choose will want a higher stall TC and gears to recover the out of gate performance lost by that cam.
So in my thinking I would upgrade the TC and gears first, to be ready for the cam. If you don't already know this, every cam size will move the operating characteristics up about 200 rpm. So going from say [email protected] to 220@ .050 is about 3.5 cam sizes, and so the power peak rises about 700 rpm. And so does the torque peak. And so does the off-idle torque. Power takes rpm,for the most part. So a cam is always trading away low-rpm power/torque for hi-rpm power/torque. Normally aspirated,that's just the way it works. Eventually you have an engine that pulls super hard from say 5500 to 7000, but needs all kinds of help below 3000rpm.And the powerband becomes more and more focused.
So in a streeter,with a small engine, it is all-too-easy to get carried away with too much cam. And if the cylinder pressure does not keep pace, disaster is lurking at the results.
Then you have the gearing issue. Say you had an operating range of 1000 to 4500 like maybe a stocker. That's 3500rpm operating range. So revved right out with 2.76s you might have shift speeds of 52/87/and127mph.
But with a big cam, the operating rpm might realistically be from 3000 to 7000, and revved right out, the shift speeds might be 80/136 and197mph, with those same 2.76s. Well one of those is pretty useless, and second ain't much better. At the other end, this cam would need a huge TC to get moving reasonably well cuz of the bottom-end torque loss.
So what do you do? You re-gear it to fit your driving application. Maybe you are a racer and are looking for 120 in the qtr, so you might put 4.56s in it, and a 4500TC. BUt that's not gonna fly for a streeter. 3.55s are the go-to for a streeter allowing some semblance of hiway operation. Well that's still not gonna fly cuz first gear is good to 65 mph, and the crazy TC while being a real hoot, is not the best thing since the invention of sliced bread. So it has to come out, and immediately the soft bottom end becomes apparent.
So what to do?
Middle of the road is what to do. Sacrifices and adjustments to fit everything into the budget, and to fit your driving requirements, and to fit the engines ability to absorb a bigger cam with a lowered cylinder pressure. In other words how much low-speed torque,driveability, fuel economy, etc; are you willing to give up?
So if you didn't already know this; now you do.
I can tell you that I did not like the 292/108 cam in my 360LA with 3.55s. No way! Lots of top-end power, a great midrange rush, but even with 11.3 Scr. the bottom end was just too soft.And of course there was the speed thing mismatch remaining. First gear was good to over 60mph. I tried several rear ratios before settling on 4.30s, to get some kind of bottom end torque back.That's an example of too big. And I had lots of cylinder pressure, that's the thing. I got rid of that cam in a hurry.
Having had too-big, I now had a pretty good idea of what I didn't want. So I got me a 270/110 fast-rate cam.And I reduced the Scr to 10.9. Now that was a real nice DD cam. But of course it was soft on top now. So again I experimented with gearage. Lots and lots and lots of gearage. In the end I learned that once you get into a gear that you want to trap with, it don't matter how many more gears you have. And once you are in that gear, the only thing that counts is power. If your engine is too small, or the cam is out of breath,or the heads are choked, disappointment is right there.
So after about 4 years that cam began dropping lobes, and out it came. So I phoned Hughes, and told them of my plight, and what cam I might be happy with. Turns out they wanted to sell me another big cam. I said no,been there done that. So I got me the current 276/110 cam. I gave up some low-speed torque for sure, but I got some serious top end back. Middle of the road.And I was able to give up all that gearage for something a lil more sane.
So no, I am not recommending that you run out to get a 276/110. Remember, I'm making over 180psi cylinder pressure. How much are you making? See, that's the limiting factor. Too much pressure and the engine wants to self-destruct. Too little and things get soft in a hurry. The cam just sets the operating range, and the published numbers are little more than guidelines.
Your target with iron heads is about 165 psi. That's where the power is. And detonation can be right close to that, with open chamber no-swirl/no Quench heads.
100psi makes a dog of an engine, You'll need a lot of help to get off the line.
120 is still very soft, you'll need a Big TC and gears to get happy
140 is sorta acceptable with a hi-stall, and 3.55s
150/155 is where things start to gel for a streeter
165 may be the upper limit for iron heads and pumpgas.
170 has been posted as doable with some good combos.
185 requires a change to aluminum heads
195 requires aluminum and tight-Q. I ran this for a short while, with no evidence of detonation.
205 and up is sorta off limits, but there are a few fellows on FABO that say they have been able to make it work.
So this would be your after new cam is installed targets. If you are already at below 150, forget a bigger cam, unless you are prepared to cough up more money for a TC and gears. The stock 252cam in a 9.0 360 might make 150 psi when new. Each bigger cam might drop the pressure 2 to 4 psi, depending on what the LSA is doing. But the VP index which indicates what the engine feels like in the bottom end can change over 8 numbers per cam size and that's a lot! What that means is that even tho going from the 252/112 stock cam to a 273/110 cam the pressure might only drop 10 psi; the V/P might drop twice that, turning a strong stock bottom end into a weiner.
My engine has a V/P of 153 and has a dynomite bottom end now.
Your 5.9 stock might be 142. With a 273/110 that might drop to 123. An 8.0 slanty might have 118. Get it 118 to 123. Don't go down there
If you put a teener cam in that 5.9, the V/P might jump from 142 to 145, just to give you an idea.
A 10/1- 400 might have the same V/P as do I,namely 153
V/P is very useful to understand why a strong engine turns into a weiner after a cam install.
See it here;
V/P Index Calculation
Last edited:
Ahhhh that's my buddies pages.
Fellow Islander he is!
He has a lot of tech in them there pages.
Fellow Islander he is!
He has a lot of tech in them there pages.
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