what heads do you guys recommend for my 93 gt?
- Thread starter Killer5.0
- Start date
Still looking for actual graphs, haven't had much time, but here is a runn down of a guy on another boards run down of his dyno. Cafield 195 heads on a pump gas 289 +.060 So those heads would be "HUGE" for that motor right.
Quoted from 289nate SBFtech... With Jay's help my junk made 400 hp at 6,000 rpm, peak hp at 6,900-7,000rpm, .93 ft/lbs of torque per cube at 2,800 rpm (lowest it was pulled), and peak torque at 5,300 rpm with 195 Canfields, Parker Funnel Web intake (the one most say will want to rev to well over 7,000 rpm on a 347), 10:1 compression, 1 5/8 stepped into 1 3/4" Stahl dyno headers with huge dyno exhaust pipes.
If the pull was stopped at 6,000 rpm people would say it's making great power for a low rpm street .060 over 289. Yet it has another 1,500 or more rpm of butt whoopin' left. Shift it at 6,000 rpm and it'll be fast for a simple low rpm 289. Shift it at 7,500 and it'll be fast for a simple street / strip 289. Isn't that what most want out of a fun street combo?end quote
So that's .93 x 299 278.07 ft.lbs@ 2800 RPM, on top of that minimum cross section on a canfeild 195 equals that of 200+ AFR heads Also with a (whats considered "HUGE") single plane intake. I know its not at 2000-2500, closest example I could come up with, with my free time.
Quoted from 289nate SBFtech... With Jay's help my junk made 400 hp at 6,000 rpm, peak hp at 6,900-7,000rpm, .93 ft/lbs of torque per cube at 2,800 rpm (lowest it was pulled), and peak torque at 5,300 rpm with 195 Canfields, Parker Funnel Web intake (the one most say will want to rev to well over 7,000 rpm on a 347), 10:1 compression, 1 5/8 stepped into 1 3/4" Stahl dyno headers with huge dyno exhaust pipes.
If the pull was stopped at 6,000 rpm people would say it's making great power for a low rpm street .060 over 289. Yet it has another 1,500 or more rpm of butt whoopin' left. Shift it at 6,000 rpm and it'll be fast for a simple low rpm 289. Shift it at 7,500 and it'll be fast for a simple street / strip 289. Isn't that what most want out of a fun street combo?end quote
So that's .93 x 299 278.07 ft.lbs@ 2800 RPM, on top of that minimum cross section on a canfeild 195 equals that of 200+ AFR heads Also with a (whats considered "HUGE") single plane intake. I know its not at 2000-2500, closest example I could come up with, with my free time.
Yes that is one impressive 289 I thought of that build the second this thread started, but I don't think he has graphs 
. Either way it's bad ass, for something that is "all wrong" 
ok it's really 297ci but still.
On edit:
Adding this as a comparison
1988 mustang 5.0L
302 NA
AFR 165's
Trick Flow Track Heat
CI hyd roller
24# Injectors
Pro-Mass air
And it's all done before 6000 RPM, was it designed that way? Not sure same cam grinder.
It has about 255tq at 2800, compared to 287tq at 2800 (from above post) AND it is down 5 cubes (302 vs 297). AND it winds out to 7500PRM
. Either way it's bad ass, for something that is "all wrong" ok it's really 297ci but still.
On edit:
Adding this as a comparison
1988 mustang 5.0L
302 NA
AFR 165's
Trick Flow Track Heat
CI hyd roller
24# Injectors
Pro-Mass air
And it's all done before 6000 RPM, was it designed that way? Not sure same cam grinder.
It has about 255tq at 2800, compared to 287tq at 2800 (from above post) AND it is down 5 cubes (302 vs 297). AND it winds out to 7500PRM
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Just as a round about, guessing a stick take around 10% off for drivetrain loss.The 289 at 2800 rpm you'll end up with damn close to the same numbers. This is all speculation any way seeing we can't compare apples to apples. For a long term example, I picked up a 331 cheap for my wifes car with itty bitty Performer RPM (newer castings) 2.02 valves. I'll run it on a chassis dyno this summer, and bring it back to the same dyno after I get the new cam and FAC heads on it from my cam desighner next season. See how the tourqe curve has been affected.
That would be a nice comparison to see though and could prove the point. Does the current combo have a custom cam as well.
I think typical drivetrain loss is more like 15% on a stick . . .and I've read somewhere before that dynojets read high by about 7% . . .and considering the 289 was likely not with comparable parasitic accessories/exhaust the numbers would stack up in the same neighborhood well within the large uncertainty of this numbers game to say which makes more. So I agree that this is not a good comparison to prove the point.
I keep thinking that there has got to be a better comparison. Seems pretty straightforward (, and critical to updating old school train of thoughts and methods) to run a combo, swap components while still on the engine dyno, then run again. . . .don't they do this on a regular basis in the mags (albeit hardly ever well thought out)??
I think typical drivetrain loss is more like 15% on a stick . . .and I've read somewhere before that dynojets read high by about 7% . . .and considering the 289 was likely not with comparable parasitic accessories/exhaust the numbers would stack up in the same neighborhood well within the large uncertainty of this numbers game to say which makes more. So I agree that this is not a good comparison to prove the point.
I keep thinking that there has got to be a better comparison. Seems pretty straightforward (, and critical to updating old school train of thoughts and methods) to run a combo, swap components while still on the engine dyno, then run again. . . .don't they do this on a regular basis in the mags (albeit hardly ever well thought out)??
Are you looking for exaples to proove what I am saying is wrong? Trying to find exact same comparisons isn't as easy as it sounds, I don't own a dyno shop. You can find alot of info backing up what I'm saying, and plenty of what you're saying. I'm not going to cut and paste, it's tacky. LOL With every combo you'd have to tune and change some parts to benefit though, not just change 1 part. I honestly won't put a set new of heads on my motor without doing the cam, I'd end up paying for the valve springs twice. I'll buy a cam/head package get the right valve springs in one shot, not a generic up to whatever lift spring. Do you not think Magazines have an agenda, who pays for adds? Some time (mid 90's) ago I ran into a guy that was building a 4.3 chevy motor to put in a chevette, There was an article on this in Car Craft in the mid 80's, after calling CC umpteen times to ask questions about the install, they finally admitted the build was never completed or actually ran. At least that's what I was told, the guy had no reason to lie to me.
I want to bring an opposite example up. My wifes old 93 GT came with 310cid, a set of worked 66 289 heads 1.84/1.54 valves 54 cc (If you know the heads, they have very small ports) an F303 cam, stock intake,TB, MAF, 5-speed, 3.08 gears. The car made absolutely terrible low end, descent mid range 3500-5000 and gassed out about 5600 up, and was very hard to drive out of the hole. I changed that combo with a quickness. Obviously the small heads and velocity did not help with low end torque, the cam was the culpret. You honestly don't think that cam choice would compensate for the the different velocity of a big head? I actually talked to doug today (EHARacing) and we'll probably be running his brothers big headed 306 on the same dyno as my wifes small headed 331, they'll have the near same accesories,gears, trans, and similiar cams (neither custom), converters are 800RPM different. Different combo's, but may give you a better comparison. I'd bet the'll come out with similiar results only the 306 will HP # higher, even though on paper it would look the 331 is set up for more low end than the 306.
I want to bring an opposite example up. My wifes old 93 GT came with 310cid, a set of worked 66 289 heads 1.84/1.54 valves 54 cc (If you know the heads, they have very small ports) an F303 cam, stock intake,TB, MAF, 5-speed, 3.08 gears. The car made absolutely terrible low end, descent mid range 3500-5000 and gassed out about 5600 up, and was very hard to drive out of the hole. I changed that combo with a quickness. Obviously the small heads and velocity did not help with low end torque, the cam was the culpret. You honestly don't think that cam choice would compensate for the the different velocity of a big head? I actually talked to doug today (EHARacing) and we'll probably be running his brothers big headed 306 on the same dyno as my wifes small headed 331, they'll have the near same accesories,gears, trans, and similiar cams (neither custom), converters are 800RPM different. Different combo's, but may give you a better comparison. I'd bet the'll come out with similiar results only the 306 will HP # higher, even though on paper it would look the 331 is set up for more low end than the 306.
Here are some Ford Head Flow Data and Specs
http://www.carbdford.com/tech/flowdata.htm
http://www.carbdford.com/tech/headflow.htm
http://www.carbdford.com/tech/flowdata.htm
http://www.carbdford.com/tech/headflow.htm