Weighed my car.. plugged figures into dyno program..
04-06-02, 10:01 PM
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Weighed my car.. plugged figures into dyno program..
Well, I went to the dump and weighed my tank...
2948 lbs with me in it.
Holy crap.
So that 2793 without. I have a stereo, box, ground effects, full A/C, PS, all that. I guess it's OK.
Anyways, with a dyno/drag racing program, I plugged that weight in with my 14.54 1/4mi run, and I got 189.5 RWHP.
That was before a number of mods, including my S-AFC (biggie) , a 2 1/4" Y pipe, and replacing my gutted cat with a borla.
I know my car is definately faster now, so 200 RWHP is easily a possibilty!
That means 230 crank HP?? To me, that might seem a LITTLE high, but I won't jump to any conclusions before I actually get it dyno'd.
I don't know how accurate these dyno prgrams are, since gear ratios can play a major factor, but it gives me a ballpark figure.
If someone asks me how much HP I have, I'll still say "I don't know- somwhere between 150 and 500" I hate people that say something. but can't back it up properly!
Anyways... just rambling on.
I guess I know why I get 14 MPG now!
Dan
2948 lbs with me in it.
Holy crap.
So that 2793 without. I have a stereo, box, ground effects, full A/C, PS, all that. I guess it's OK.
Anyways, with a dyno/drag racing program, I plugged that weight in with my 14.54 1/4mi run, and I got 189.5 RWHP.
That was before a number of mods, including my S-AFC (biggie) , a 2 1/4" Y pipe, and replacing my gutted cat with a borla.
I know my car is definately faster now, so 200 RWHP is easily a possibilty!
That means 230 crank HP?? To me, that might seem a LITTLE high, but I won't jump to any conclusions before I actually get it dyno'd.
I don't know how accurate these dyno prgrams are, since gear ratios can play a major factor, but it gives me a ballpark figure.
If someone asks me how much HP I have, I'll still say "I don't know- somwhere between 150 and 500" I hate people that say something. but can't back it up properly!
Anyways... just rambling on.
I guess I know why I get 14 MPG now!
Dan
04-06-02, 10:58 PM
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Oh sweet GOD! SWEET! Please tell me you are getting your car dyno'd soon, as I'm building a motor very very similar to yours, but putting it in a light weight 87 chassis. I'm hoping 2600 llbs wet w/ driver. High 13's would be insane!
04-07-02, 12:48 AM
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pp13bnos claims that he had an N/A that was very low 14's... he had a stock port engine with bolt ons, probably only 170 HP BUT he said he weighed 2200 lbs!
He has a time slip from a high 14's run with a freind in the car!
Weight plays a big factor with a low-torque 13b (um, all of them!) .. I'm sure a 200lbs savings from the car I have would absolutely net another .25 EASY. Probably more like .4 sec
I am not a "poseur"... I still stress that the 190 rwhp is just a calculation... who knows what it actually is.
But hey, I guess low 14's for a 2900 lb rx7 is alright!
He has a time slip from a high 14's run with a freind in the car!
Weight plays a big factor with a low-torque 13b (um, all of them!) .. I'm sure a 200lbs savings from the car I have would absolutely net another .25 EASY. Probably more like .4 sec
I am not a "poseur"... I still stress that the 190 rwhp is just a calculation... who knows what it actually is.
But hey, I guess low 14's for a 2900 lb rx7 is alright!
04-07-02, 06:31 AM
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VERY nice Bambam.......I hope to pull 14's from a 2300lb(???) 87 SE sometime in the near future........how much power you think I would need to pull that magic trick off?
04-07-02, 12:57 PM
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My figures show that to get a 2948lb car to do 14.54 will require 190hp at the flywheel. A more accurate way to calculate is by using the MPH figure since the MPH is determined mostly by power/weight, while E.T. is determined mostly by driver skill and how well the car launches.
I use the DSM.net calculator at http://www.dsm.org/tools/calchp.htm BEWARE though - it does NOT give RWHP like it claims, it gives flywheel HP! The formulae were written in the 50's by Chrysler engineers and are incredibly accurate in calculating flywheel HP. For proof that it generates flywheel HP, put in the numbers for a stock RX-7. Let's say a '79 model with a test weight of 2600lb, which will run 17-flat at 80mph according to road tests of the day. The formulae calculate 104-105hp. The '79 was rated at 100hp flywheel.
I use the DSM.net calculator at http://www.dsm.org/tools/calchp.htm BEWARE though - it does NOT give RWHP like it claims, it gives flywheel HP! The formulae were written in the 50's by Chrysler engineers and are incredibly accurate in calculating flywheel HP. For proof that it generates flywheel HP, put in the numbers for a stock RX-7. Let's say a '79 model with a test weight of 2600lb, which will run 17-flat at 80mph according to road tests of the day. The formulae calculate 104-105hp. The '79 was rated at 100hp flywheel.
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04-07-02, 01:50 PM
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A few questions about your mods.
What size exhaust are you running? and is it dual, or single?
Do 3mm Apex's, and race bearings do much for power?
Where/what kind of SP did you get? Mild? ( 4 of the 6 ) or full? ( all of those puppys)
What kind of gains ( Seat-of-the-pants dyno ) did you get from porting/matching/polishing the intake
and lastly... what kind of Electric fan are you running?
What size exhaust are you running? and is it dual, or single?
Do 3mm Apex's, and race bearings do much for power?
Where/what kind of SP did you get? Mild? ( 4 of the 6 ) or full? ( all of those puppys)
What kind of gains ( Seat-of-the-pants dyno ) did you get from porting/matching/polishing the intake
and lastly... what kind of Electric fan are you running?
04-07-02, 02:34 PM
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2 1/2" with 2 1/4" dual catback. Wish I had a 3" single though.
3mm apex seals- BIG debate. BUT- overall, you lose a tiny (almost unmeasurable) compression at lower RPMS.- Basically no difference.
You get much better detonation resistance though. A few good pings can kill 2mm seals, but 3mm seal can take a LOT more abuse, so you can run a tad leaner/hotter, with a bit more advance, to make more power. They can STILL break though if you are a psycho.
Race bearings- no power increase, but they are better balanced, have closer tolerances, and take high RPM 's much better. They have a different oiling system too.. more open or something (I never saw them)
The 4 main intake and exhaust ports got enlarged/extended, and the auxillary intakes got radiused and smoothed.
I am not done the intake, and I have no idea how much power I got from it, because I did it when I installed the new engine.
Perma-cool. It can pull the car up a hill if you want!!
3mm apex seals- BIG debate. BUT- overall, you lose a tiny (almost unmeasurable) compression at lower RPMS.- Basically no difference.
You get much better detonation resistance though. A few good pings can kill 2mm seals, but 3mm seal can take a LOT more abuse, so you can run a tad leaner/hotter, with a bit more advance, to make more power. They can STILL break though if you are a psycho.
Race bearings- no power increase, but they are better balanced, have closer tolerances, and take high RPM 's much better. They have a different oiling system too.. more open or something (I never saw them)
The 4 main intake and exhaust ports got enlarged/extended, and the auxillary intakes got radiused and smoothed.
I am not done the intake, and I have no idea how much power I got from it, because I did it when I installed the new engine.
Perma-cool. It can pull the car up a hill if you want!!
04-07-02, 02:56 PM
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Originally posted by Bambam7
2 1/2" with 2 1/4" dual catback. Wish I had a 3" single though.
3mm apex seals- BIG debate. BUT- overall, you lose a tiny (almost unmeasurable) compression at lower RPMS.- Basically no difference.
You get much better detonation resistance though. A few good pings can kill 2mm seals, but 3mm seal can take a LOT more abuse, so you can run a tad leaner/hotter, with a bit more advance, to make more power. They can STILL break though if you are a psycho.
Race bearings- no power increase, but they are better balanced, have closer tolerances, and take high RPM 's much better. They have a different oiling system too.. more open or something (I never saw them)
The 4 main intake and exhaust ports got enlarged/extended, and the auxillary intakes got radiused and smoothed.
I am not done the intake, and I have no idea how much power I got from it, because I did it when I installed the new engine.
Perma-cool. It can pull the car up a hill if you want!!
2 1/2" with 2 1/4" dual catback. Wish I had a 3" single though.
3mm apex seals- BIG debate. BUT- overall, you lose a tiny (almost unmeasurable) compression at lower RPMS.- Basically no difference.
You get much better detonation resistance though. A few good pings can kill 2mm seals, but 3mm seal can take a LOT more abuse, so you can run a tad leaner/hotter, with a bit more advance, to make more power. They can STILL break though if you are a psycho.
Race bearings- no power increase, but they are better balanced, have closer tolerances, and take high RPM 's much better. They have a different oiling system too.. more open or something (I never saw them)
The 4 main intake and exhaust ports got enlarged/extended, and the auxillary intakes got radiused and smoothed.
I am not done the intake, and I have no idea how much power I got from it, because I did it when I installed the new engine.
Perma-cool. It can pull the car up a hill if you want!!
WOOHOO!!! This is good news for me. I've got ALMOST the same setup planned. All this done as soon as... I GET THE GODDAMNED FLYWHEEL OFF!
04-07-02, 05:57 PM
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too sweet
hey bambam....
i have been concedering using an afc on my NA. internally our engines are the same except i have 2mm carbon apex seals, so i would expect similar results like you are getting. any info, or tricks/hitches you ran into getting it tuned?
peace
i have been concedering using an afc on my NA. internally our engines are the same except i have 2mm carbon apex seals, so i would expect similar results like you are getting. any info, or tricks/hitches you ran into getting it tuned?
peace
04-07-02, 09:52 PM
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I havn't properly had it tuned yet, I just estimated off of engine response, sound, and ran on the rich(safe) end of what some other NA's have set with their S-AFC's. But every car is different. I have a wideband I am building, when it's done, I'll be able to tune it properly, with the help of my G-Tech's instant G function.
I should get another 10 HP maybe from proper tuning.
Right now, for high throttle, I have it leaned out by about -9% up to around 6000, then about -4% from 7000 to 8000.
I should get another 10 HP maybe from proper tuning.
Right now, for high throttle, I have it leaned out by about -9% up to around 6000, then about -4% from 7000 to 8000.
04-14-02, 01:32 PM
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found a quick calculator that gives you a snap shot of both flywheel and rear wheel
http://www.gordon-glasgow.org/hpcalc.html
TJ
http://www.gordon-glasgow.org/hpcalc.html
TJ
04-14-02, 08:06 PM
#14
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Damn your car weighs about as much as mine. 
I'm a smaller guy though, but I also have PS, AC and a couple 10s in the back.
I'm glad to see that you didn't rip everyting out of the car, which seems to be the popular thing to do for some reason...
I'm a smaller guy though, but I also have PS, AC and a couple 10s in the back. I'm glad to see that you didn't rip everyting out of the car, which seems to be the popular thing to do for some reason...
04-15-02, 03:42 AM
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04-15-02, 09:07 AM
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Hey those are bolth pretty cool. If those programs are right, i'll be putting down 174 rwhp. 170-180rwhp is my goal. My dyno session was post poned for a couple days. I'll keep everyone up to date though.
Bambam, to get the most power out of it, i'd just take it to a dyno. From what Rob@Pineapple told me, every engine will be a little different, so there is no set a/f ratio for a rotary.
Hey, wheres my ecu? CJ
Bambam, to get the most power out of it, i'd just take it to a dyno. From what Rob@Pineapple told me, every engine will be a little different, so there is no set a/f ratio for a rotary.
Hey, wheres my ecu? CJ
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