Redlines!!!

[DJ Nexxus]

can anyone tell me how you go about calculating the redline of an engine??

[Doom]

yuh doh calcualte it, it is manufacturer set
only if the head config was altered then new limits would be set

[DJ Nexxus]

alright so if you rebuild an engine, and you mod it out.....anyway to tell your redline??......

[Tired Accord]

breds - use the original stock engine redline as a guide. if you have upgraded your internals - ie - valve springs, camshaft(s), pistons, rods, etc - you should be able to carry it past the stock redline on a regular basis. I seriously doubt that there is a computation / formula to figure out this, as there are too many factors involved. You might be able to get another 1000 - 1500 rpm more with upgraded internals. Hope that helps.

[Aaron 2NR]

jus dyno the ting an see where power falls off

[DJ Nexxus]

jus dyno the ting an see where power falls off

BINGO!!!...ah thought this was the answer, just wanted to hear someone else say it!...

Thanks for D help fellas

[streetsleeper2]

Ok so would modifyin your ecu to get a higher redline make sense?? That is without upgrading your engine internals.

[DJ Nexxus]

If it is me you are directecting that statement to Sleeper, I don't have an ECU in my ride.....strictly old school

[Samiir_Tuner]

Ok so would modifyin your ecu to get a higher redline make sense?? That is without upgrading your engine internals.

yes it would..not in all cases though but i know with certain honda engines it comes limited at 8000rpm but with the ecu chipped u can take it to 8500rpm making power all the way up

[streetsleeper2]

ok i drive an sr18 automatic lsd with slight mods nothing internal though. Would this make sense in my case. fuel cut is at 6500rpm

[cdx2k1]

It doesnt make sense increasing the redline if power just drops off in the higher range...or so it's said..but my thing is, when you shift in this higher range, you'll drop back lower down...but higher than where you would normally drop if you had the original redline..I think you should have access to more power this time as you drop..but that's just my thinking.

[DJ Nexxus]

Always ask questions

Keep this in mind as I make the following remarks, as they are not meant in any negative way.

It doesnt make sense increasing the redline if power just drops off in the higher range

Isn't the redline of your engine the line at which power begins to drop off?

when you shift in this higher range, you'll drop back lower down...but higher than where you would normally drop if you had the original redline..I think you should have access to more power this time as you drop

Yuh kinda lost me there with that one CDX, no malice intended, do you mind elaborating further?...

Oh and people...does anyone know where I can get my ride dyno'ed??? or if anyone in trinidad does it at all?

[cdx2k1]

It doesnt make sense increasing the redline if power just drops off in the higher range...Isn't the redline of your engine the line at which power begins to drop off?

Yes>So i've been told.I've seen some sr20 online dyno sheets too where the HP/tq is @ it's highest @ the redline (stock).

when you shift in this higher range, you'll drop back lower down...but higher than where you would normally drop if you had the original redline..I think you should have access to more power this time as you drop..Yuh kinda lost me there with that one CDX, no malice intended, do you mind elaborating further?...

I'll use these vids to try and illustrate my point:
http://www.youtube.com/watch?v=0_S4KwtlBx8
http://www.youtube.com/watch?v=BOs-8zOTQAw&NR=1

See how the RPM drops when gears change @ X RPM?Let's say, it drops down to 6,000 for the Sykline..you have Y Hp/tq @ 6k RPM.My thing is...if you push the redline past X, to about X + 700RPM, wouldn't the RPM it drops back down to (@ the gear shift) be higher than 6,000RPM?..
Therefore, the HP/tq of the higher RPM that you drop back down to, must be higher than Y hp @ 6k RPM..
I hope I explained clearly..that's just my tought process on the thing..Im not sure if this is correct or not.I don't know if an engine would drop back down to a preset RPM all the time, but im thinking the RPM it drops back down to also depends on the gear ratio of the gearbox/tranny..soo..

[DJ Nexxus]

ok ok I hear ya now...and yeah when you cross redline (and I say this from my personal experience only) and you shift you will drop to a higher RPM level than if you had shifted normally, BUT you would have wasted time trying to get power out of the engine between the redline and whatever higher point you shifted from...ie... you just lost the race!...lol

[cdx2k1]

^^Exactly.lol.That's why the fellahs say it doesnt make sense unless you have more power to get or give @ those higher RPM's.But i'd really like to do a head to head of 2 similar vehicles/engines and see which of the two would be faster.

[DJ Nexxus]

my money on the man who shift properly, and anyway the original problem I was trying to figure out was....like I said I rebuilt a L28 engine and I am currently installing twin turbo in it...changing the pistons cams, rockers, springs, ie: increasing the redline I wanted a pretty good idea where that redline is.

[cdx2k1]

^^Well, dyno!lol

[DJ Nexxus]

lol...ok ok ok....sorry boss...lol