Automatics.

[FuncOvrForm]

How much hp or if any is lost vs. a manual?

[BlackMagicCB7]

Automatic is definately a for head to head races. But I don't know the exact power loss or calculations... when it comes to performance.

[FuncOvrForm]

Automatic is definately a for head to head races. But I don't know the exact power loss or calculations... when it comes to performance.

y is that? cuz of the reason not being able to downshift?

[Ralphie]

Yes.

Standards own Auto's because with a standard tranny you can better control the powerband.

As far as how much is lost, i dont know if there is an amount that is lost just that it isnt as usable persay is with a 5spd.



BTW- and unless you really know what the fuck your doing, manuals own as far as launches too....feathering and double clutching and heel-toe....

techniques that i dont think can really be applied in an auto, well wouldnt really have a need.

[MadSpleen85]

I have always wondered this...

The ultimate test would be to get two CB's one automatic and one manual, with the exact same or no mods, and close to the same mileage/condition of the motor and tranny and throw them on a dyno.. With car as old as ours that would be hard to do..

The way automatics are advancing in newer technology the gap is probably closing, at least a little bit, from when our cars were made.. Later

[BlackMagicCB7]

^^^ Yep, being able to select your gears on demand for best efficiency whether it be racing or commuting is the advantage over an automatic.

[T3aM 83rD]

I had a 90 EX 2dr auto and now I have a 90 LX 2dr 5speed, both car have about the same mods, nothing major, I/H/E

My friend has a 2001 TL type S (auto)

With my old car racing from a stop he always jumped and continued pulling, I would never gain any.
This past weekend we raced from a stop with my new car, I jump and stayed infront until i was shifting into third gear then he passed and continued pulling, He said that it was because of his traction control but still with my automatic i could never do that.

I havent mastered the downshifting so I can't give a fair judgement on "highway racing"

[BB6-SH]

being able to downshift is the upside and i would think because of the torque converter an automatic would make less power not sure on that one. But yeah for racing it helps sometimes when i'm on the highway depending at which speed i'm at i can drop it down to 3rd, but i have to shift fast or else.

[NAiL05]

You will lose slightly more. Imma say about 20% around there for fwd auto. NOrmal manual fwd trans is about 15% as I recall. Those are the genral ruless. Autos have more drivetrain loss because there is just more going on in them plus they are heavier. You have the added weight and work of a valve body, shift solenoids, Torque Converter, Clamping the clutch packs with hydraulic fluid its quite a bit of work compared to a manual trans. Manual trans you shift years by your arm, engage/disengage controlled by your foot, No others really to worry about (its more mechanical if you wanna say). With these less things it allows the engine to free up HP. The best place where autos shine believe it or not is the dragstrip in higher HP apps. Most of the 6-7 second imports/domestics are running an auto. TH400 seems to be a popular choice (RWD trans) This trans is basically bulletproof. IT is similer to its brother the TH350 but I think it has one more gear I forgot. Its a heavy sone of a bitch and basically maintenance free which is a benefit compared to a manual trans where you have to change out the clutch once it fried, mis shift can cause you troubles. Also you can build up torque faster with an auto. But yea a great place where manual trans or sequential is your race track with the ability to select gears. Of course a manual car will be faster than an auto in most cases not all. Most valve bodies/auto trans design is conservative out of the factory nowadays and built for "comfort" Not really performance aspect except for a few. A good example of a new type of sequential/auto trans would be the BMW seven speed trans used in the M5. You can adjust shift pickup which is a nice add on. But for normal street cars like a civic manual vs auto the manual one will win. Heres a good OEM comparison of same car but auto is faster. The new 911 turbo with variable vane turbos. The auto is faster because you can spool off the line unlike the manual trans where you have to find the sweet spot to launch. Top speed might be sacrificed a bit but low end the porsche auto wins. But yea Manual or Auto you will have drivetrain losses and the auto will usually have more. There are pros and cons to both so yea.

[Ralphie]

yea i know on autos there is the rev limit or whatver but i know youd do damage if you tried downshifting and it hit redline and didnt shift.

I know from 1 and 2 it doesnt shift on its own....just D3 and D4 i think.

Either way with an auto it just doesnt work so i dont know why anyone shifts thru the gears...i leave it in D4 unless i wanna rev or i am actually using D3 and such for low rpms like they were suppose to be used.

[NAiL05]

yea i know on autos there is the rev limit or whatver but i know youd do damage if you tried downshifting and it hit redline and didnt shift.

I know from 1 and 2 it doesnt shift on its own....just D3 and D4 i think.

Either way with an auto it just doesnt work so i dont know why anyone shifts thru the gears...i leave it in D4 unless i wanna rev or i am actually using D3 and such for low rpms like they were suppose to be used.

Rev limit? Tried downshifting to redline? This is where the TCU comes into play. If it senses your out of gear when your "downshifting" in the auto it will not downshift to that gear until that speed is reached to prevent you from blowing up your motor. Up shifting you can bring past redline down shifting is a diff story. For example back in my ricer daays in my 90 EX i was racing a sentra and a curb was comin up. I accidentally threw it in d2 but the car went into d3 instead. The TCU sees that the speed does not match the rpm where its programmed (guess thats how you can explain it) so it goes to d3 to slow down the car then it will go into d2. So technically you cant really mess anything up downshifting other than the internals of an auto trans.

[Lantis]

actually it depends though. on some cars the automatic is faster.

there was some guys who did some freeway racing vids around here and the one guy was in an automatic and the guy in the manual could tell that when the automatic shifted it would keep pulling.

now also, I know at least have a dozen guys with Z32's and more than one has said that the automatic is quicker than the manual in the quarter mile. and they aren't noobs either, they all know their cars pretty well, and know if it's just noobery that one car is faster than another..

so I really think it depends on the car, not all automatics shift short, I can take my CB to the redline if I am flooring it. and in my mom's saturn, if you are in a high gear, and floor it, the automatic downshifts to a lower gear to get into high rpm's, and then shifts back up when it redlines. and if you think I am bullshitting you, think about this, we took this car to a mechanic that we have been going to since before I was born. He owns his own shop, and up until this past year, owned his own race car and race team (sprint cars, dirt tracks). He is no slouch when it comes to performance cars and we took the car in to have a couple things looked at and this is what he said when he was giving the car back "man, that thing pulls hard, even for a V6, it's just keeps wanting to go harder".. the engine is a "180 hp" (what the car is supposed to have, but it feels like it's got alot more in it and is just being limited), V6 built in germany. I think it was originally a saab designed motor or whoever that is that works with GM, the car itself is based on an opel vectra platform. and I've surprised a few people who didn't think it had as much power as it did until I put the pedal down and it walked off on them.

[BlackMagicCB7]

Wow NAiL05 your knowledge is beyond what I know..... pretty impressive, I learned something I already didn't know about standard vrs. automatic.

[FuncOvrForm]

so would a h22 auto be a good contender?

[NAiL05]

A good contender for what? It is geared a lil more aggressive than the F. I dunno I just woke up from a nap and typed all that up lol. Most of it is common sense anyway!