A barely streetable car that people will people will unmistakably know is bad ***.
Another, Damn it, horsepower guess ??
- Thread starter Brooks James
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Dartswinger70
Well-Known Member
Tell that to the 318 guys .Cross thread points!...
Dartswinger70
Well-Known Member
Or..a car that will lay rubber for a full city block...
rmchrgr
Skate And Destroy
Aaahhh, gotcha. I have one of those "barely streetable" cars and trust me, it gets old. Loading up at idle, loud exhaust, lots of heat in the trans and motor which can be tough to manage... But hey, if that's what you want... You likely understand that most of the time you're at part throttle on the street so you'll rarely be using half of that 550hp anyway.
If it were me I’d forget about the solid roller and try to find a flat tappet grind that makes power at a lower RPM. Nobody will know what kind of cam it is unless you tell ‘em. Then you won't need roller valve springs and your current converter and gears should be fine if you keep the duration @ .050" reasonable.
If it were me I’d forget about the solid roller and try to find a flat tappet grind that makes power at a lower RPM. Nobody will know what kind of cam it is unless you tell ‘em. Then you won't need roller valve springs and your current converter and gears should be fine if you keep the duration @ .050" reasonable.
Dartswinger70
Well-Known Member
You mean like a pro stock funny car with a license plate below the "parachute" LOL! I get it and have known fellers who had them. I worked woth a guy with a tubbed 68 Chevelle with a 454,and a cage,his name was Ed. . The other guy was like "you should race Ed." I said "Ill run him but my car( 70 dart swinger 340 in street trim) isn't a race car its a little unfair don't ya think?"
This is coming to me, I think a an already package deal. I am kind of thinking that less will actually be more.
What I really want is to have it pull like a freight train from 2500-6000
I could sell the roller and rockers get a flat tappet cam and still have money left . From what I can tell this custom groundvcam with rockers retails for around 1200. I could get at least 550 for it and that would definitely get me a cam kit, cam, valve springs, retainers, locks, pushrods , lifters etc.
Dartswinger70
Well-Known Member
wouldn't the roller give you better rev capability less resistance etc?
Yes in conjunction with the roller rockers I would guess 20 or more hp loss with a flat tappet.
Dartswinger70
Well-Known Member
Do you have less choices with the roller? I never had one in a Mopar but have one in my Fox Body Mustang.
rmchrgr
Skate And Destroy
Yes but solid roller cams come with two main caveats - generally, the profiles are usually designed to work for higher rpms so the rest of the combination needs to match it or it won't work very well and #2, roller cams require much stiffer valve springs which puts more strain on valvetrain parts. All your stuff needs to be beefy enough to accommodate the higher spring pressures like thicker pushrods, good retainers etc. Unless you re drag racing the car regularly, a roller might not be worth the expense/hassle on the street. One could probably get the desired characteristics from a solid flat tappet.
Truth be told, solid cams rev pretty well. I had an Mopar .528' cam in my old 340 combo and it would go to 7,000 rpm in an instant. Drag racing it shifted 7,200. No low end torque though even with a 4.10 gear, needed a minimum 4.30 to get off the line efficiently. The O.P. has a slightly different configuration with the stroker so by default it will make more torque at a lower rpm.
if the O.P. is stuck on a roller cam, perhaps a hydraulic roller would work in this situation. The rpm range will be lower and should make more torque at a lower rpm but would likely give up some top-end hp.
aaronk785
Well-Known Member
My friends 150 kit added 130 hp and 210 tq.
yellow rose
Overnight Sensation
The problem with making the HP guess is it’s pretty meaningless as far as area under the curve is concerned.
I’m betting you cam is ground on a 112 LSA. Even with your heads (I don’t think you mentioned what headers you have) you might have a nice peak HP figure but the fat part of the curve will be piggish. I’d have to do a bit of math but my first guess is a 108 LSA in no more than a 106 ICL is about as wide as you’d want to be.
That will keep the peak HP number the same or pretty close and it will put a bunch of power back in the middle. What it will also do is drop the HP after peak way down. IOW’s, instead of carrying peak HP 600-700 RPM longer it may only carry 200 RPM longer after peak.
I’d give up that after peak number every day and 10 times on Sunday and fatten up the middle (which is what most guys claim they want anyway) that chase that after peak number.
Just my .02 and it’s actually worth less than you paid for it.
I’m betting you cam is ground on a 112 LSA. Even with your heads (I don’t think you mentioned what headers you have) you might have a nice peak HP figure but the fat part of the curve will be piggish. I’d have to do a bit of math but my first guess is a 108 LSA in no more than a 106 ICL is about as wide as you’d want to be.
That will keep the peak HP number the same or pretty close and it will put a bunch of power back in the middle. What it will also do is drop the HP after peak way down. IOW’s, instead of carrying peak HP 600-700 RPM longer it may only carry 200 RPM longer after peak.
I’d give up that after peak number every day and 10 times on Sunday and fatten up the middle (which is what most guys claim they want anyway) that chase that after peak number.
Just my .02 and it’s actually worth less than you paid for it.
Judging from the other threads...and the strange cam specs listed, you might get about 500 hp on motor, then spray it to ~650....but only be capable of running 12's in the 1/4 (maybe 11's)....just my opinion.
That's a huge cam, alot of duration for 408 cubes. I would expect that cam to be really alive from 5k up to 8k, just a guess but you might run out of air with the thermoquad
Ivoryk3ys78
Well-Known Member
I would think torque peak would be at 4750 and hp peak would be about 6500 with 260@050 and those heads. Strong 4-6500.
10:1 is pretty low with that much at 050 unless it has a pretty wide ICL and lower overlap. I would think around 11.5 would be about the right compression.
I think 550 is a reasonable guess with 1 7/8 headers and if that carb was sorted out but lower end torque certainly giving up more then needed due to the low compression/cylinder pressure for the camshaft.
It is a package deal you said but it does seem that the camshaft is the part that stands out as a bit of a mismatch compared to the current converter and compression.
If you don't like Hughes thats fine but this I think is an example of a cam that would work really well for a 3500 converter and 10:1 compression. I think think it would pull nicely to 6k and have plenty of cylinder pressure with 10:1 unless your at a high elevation.
STL4650AS-8
578/588 @1.5
246/250 @050
108 in at 104
Just my thoughts.
10:1 is pretty low with that much at 050 unless it has a pretty wide ICL and lower overlap. I would think around 11.5 would be about the right compression.
I think 550 is a reasonable guess with 1 7/8 headers and if that carb was sorted out but lower end torque certainly giving up more then needed due to the low compression/cylinder pressure for the camshaft.
It is a package deal you said but it does seem that the camshaft is the part that stands out as a bit of a mismatch compared to the current converter and compression.
If you don't like Hughes thats fine but this I think is an example of a cam that would work really well for a 3500 converter and 10:1 compression. I think think it would pull nicely to 6k and have plenty of cylinder pressure with 10:1 unless your at a high elevation.
STL4650AS-8
578/588 @1.5
246/250 @050
108 in at 104
Just my thoughts.
Are you going to run an automatic ? Because the cam you want & the converter you'll need will blow right past 2500-3500 & probably 4500 before it even gets moving & not slipping. You could get away with alot less cam to do what you want something in the 250s duration at .050. I'm not a no2 guy so I'm not sure how that will work but I'm taking a guess with the cam you want to run letting in that much no2 & fuel it's destined to be a broken block or rods or something in no time.
Keep the Holley 950 for a door stop. We will help you tune the TQ. If you want a little more air flow with the TQ, remove the choke & fast idle linkage assy. There will be a T shaped hole left in the air valve after removing the linkage shaft. Braze/weld/silver solder a small plate over the hole. Use thin metal to keep the weight down.
Yes....Every weekend when I'm at the race track all I see are TQ's everywhere.....they are on all the fast cars..........
justinp61
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Yes....Every weekend when I'm at the race track all I see are TQ's everywhere.....they are on all the fast cars..........
I thought the same thing.
Yes....Every weekend when I'm at the race track all I see are TQ's everywhere.....they are on all the fast cars..........
If the big TQ is used, (and modified appropriately) it will be enough for the street and strip. If this was just a race car, then a Holley would get the nod. The TQ has enough cfm in it to work at this level.
Bewy has done some work with a TQ, QJ and a Holley on his stuff that should show it’s worth. For a OE carb, there really excellent. To say it would stand up next to or exceed an after market race oriented carb is stretching it.
For the cost I have picked up TQ’s at plus the home rebuild, there very cost effective. Tuning/replacement parts are the draw back. There just not found at the local store.
TT5.9mag
Two atmospheres are better than one
I didnt say the TQ won’t work. I said he’d better be a guru to make it work. And I stand by that. A Holley 950hp will be easier to tune and parts availability is much easier. And probably make more power.
yellow rose
Overnight Sensation
Anything you can do to a TQ you can do to a Holley. And you can do more to the Holley. They are simple and this wouldn’t even be a question if Holley was so stupid and myopic. And if they didn’t put out piss poor tuning information.
justinp61
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I get a chuckle every time I read guys posting how Holley's are rich at idle and have poor drivability. It just proves that they never put in the effort to learn how to tune one. Just because you can run one straight out of the box doesn't mean you should.
That is not a pump gas cam IMO. Kim
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