Limits of a street ported motor
05-27-08, 10:51 PM
#27
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So what you are all saying is 8k is pretty safe as long as Im religious about maintenance, like changing the oil often. My car tends to start pulling hard after about 4500, so if I take it to 8, it doesnt drop that much and it keeps on pulling. So anyway, go back to the top of the page, look at my mods and tell me what you guys think I should have for power.
05-27-08, 10:54 PM
#29
So what you are all saying is 8k is pretty safe as long as Im religious about maintenance, like changing the oil often. My car tends to start pulling hard after about 4500, so if I take it to 8, it doesnt drop that much and it keeps on pulling. So anyway, go back to the top of the page, look at my mods and tell me what you guys think I should have for power.
I would think that with your set up, it would pull quite hard. Taking it up to 8 would be alright from what I know, after around 8500 the steel seals begin to chatter the housings.
05-27-08, 11:02 PM
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Whats the best way to tune it? Take it to a dyno with someone who knows carbs? When I got the car it didnt like to stay running at an idle. The guy I got it from asked what kind of gas I put in, I told him 87, he said that was my problem since he tuned it for 91. (yes I know this comment will probably start a whole new thread.) I got myself a webber manual and started turning screws till it sounded like it ran right. I can take it all the way to 8k in 3rd with out any problems. One problem I had before was some sputtering up high, I thought I needed a bigger volume fuel pump. The $3 fuel filter I put on fixed that problem.
05-28-08, 02:26 AM
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I look at it this way, drive it how you feel comfortable. I tried to kill a 130,000 mile 12a (in drive it hard manner not drain the oil and just rev it to high hell). Lets just say I was impressed that it still pulled well past 8000rpm in every gear except it kind of puttered out trying to stay at 8000rpm in fifth. My only regret is I didn't try to shoot nitrous through it. The only mods were no clutch fan, a sketchy header, plugs, wires, direct fire, and synthetic oil. Too bad the car fell apart around it. Still runs and has the same insignificant amount of smoke on start up.
05-28-08, 09:45 AM
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I look at it this way, drive it how you feel comfortable. I tried to kill a 130,000 mile 12a (in drive it hard manner not drain the oil and just rev it to high hell). Lets just say I was impressed that it still pulled well past 8000rpm in every gear except it kind of puttered out trying to stay at 8000rpm in fifth. My only regret is I didn't try to shoot nitrous through it. The only mods were no clutch fan, a sketchy header, plugs, wires, direct fire, and synthetic oil. Too bad the car fell apart around it. Still runs and has the same insignificant amount of smoke on start up.
05-29-08, 05:03 PM
#43
13B large extend port, RB stationary gears, 6 pd flywhl, 48ida, 10000rpm all day 
Destructive harmonics sets in on factory stationary gears at about 9500rpm so any thing up to that, (or above that for a short amount of time) is mmmmk,
mmmk?
Destructive harmonics sets in on factory stationary gears at about 9500rpm so any thing up to that, (or above that for a short amount of time) is mmmmk,
mmmk?
05-30-08, 08:38 AM
#47
Respecognize!
i don't mind revving higher just because i really don't have a choice for the class i'm in. Stock ports....
Although they do seems to allow any oiling and cooling modifications so if i had to rebuild the motor i could get away from some life increasing stuff. Plus no one really looks inside these engines anyway.
Although they do seems to allow any oiling and cooling modifications so if i had to rebuild the motor i could get away from some life increasing stuff. Plus no one really looks inside these engines anyway.
05-30-08, 09:00 AM
#48
i'm running a streetported 13b from a '74 rx4 with RB holley intake, carb, and exhaust for such, but without the presilencers, all stock internals except for the '86 e-shaft, and i drive it every single day. i've lost count but it's got 30 some odd thousand miles on it since i built it. i've wound it out a few times on the highway, but have never held it long enough to reach 8k in 5th. unless u try it real late at night when there's practically no traffic and u pray there's no cops, i don't even think it'll reach 8k in 5th. yeah wacky, i used to drive it like i stole it all the time, and then gas got so high i don't it any more.
05-30-08, 09:22 AM
#49
I live near the entrance to a local freeway (this is where the freeway starts from Dodger Stadium area). Its a lil over a mile long of on-ramp before you can actually say its a freeway. So in summary, thats where I do my test run.
Gas??? thats the least Im concerned off. I owned too many RX and in the past 2 years, they're just sitting and collecting dusts.
Gas??? thats the least Im concerned off. I owned too many RX and in the past 2 years, they're just sitting and collecting dusts.
05-30-08, 12:57 PM
#50
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the one that sucks is when the rotor gear comes out....