shane661
Needs a life
Posts: 11494
|
posted November 24, 2006 02:11 PM
Who Here Runs 12k+ Rpm?
I'm considering bringing up the revs to about 12k rpm actual. I was wondering how many of you are running extended rpm limits? I'm probably looking at more compression, and some head work, springs, etc. Just looking for some real world experiences, tips, tricks, etc. How well does it breath up there with the stock cams?
  
|
supra5677
Pro
Posts: 1279
|
posted November 24, 2006 04:29 PM
I have mine extended to 12,200 actual 12,800 showing on the tach. The engine does it easily...
|
shane661
Needs a life
Posts: 11494
|
posted November 25, 2006 06:31 AM
How many miles on that setup? What bore, valvetrain are you running?
|
supra5677
Pro
Posts: 1279
|
posted November 25, 2006 06:01 PM
5K on that set up. stock bore thin head gasket 105/103 cam timing etc...
|
NOS1290
Expert Class
Posts: 103
|
posted November 26, 2006 03:59 AM
I have about 3k on my motor with 12.3k limiter and big cams. Motor does need to be ported to make use of the revs in my opinion. However real gain is in the ability to gear lower, and accelerate harder. For example at maxton you can go with stock gearing (18/46) and break 200. If you gear up for that kind of speed with a rev limit of 11.6k, you give up way too much acceleration.
|
Phantom Menace
Expert Class
Posts: 169
|
posted November 27, 2006 01:26 PM
quote:
I have about 3k on my motor with 12.3k limiter and big cams. Motor does need to be ported to make use of the revs in my opinion. However real gain is in the ability to gear lower, and accelerate harder. For example at maxton you can go with stock gearing (18/46) and break 200. If you gear up for that kind of speed with a rev limit of 11.6k, you give up way too much acceleration.
You better make sure to inform people that you'll need much stiffer valve springs!!! The stock springs are NOT to be trusted beyond 11,650rpm!!!! If you're going to extend the RPM's (especially up to 12,300rpm) you NEED to upgrade the springs. Oh, don't go with APE springs either.... peice of crap, no better than the stockers!
|
NOS1290
Expert Class
Posts: 103
|
posted November 27, 2006 02:25 PM
Yup. Even the stock motor needs springs. Cams will fail and shims will spit out if you don't . Especially under spray. I run Kibblewite (Spelling?) and I change springs every winter.
|
shane661
Needs a life
Posts: 11494
|
posted November 27, 2006 02:47 PM
That is already in the plans. I don't mind changing them once per season. I also don't want to run more seat pressure than is needed. The APE springs start at 55psi....some others as high as 65. That is where things get murky, IMO.
|
DrRyanScarsella
Expert Class
Posts: 113
|
posted November 27, 2006 08:39 PM
WHO DOES A PROCEDURE LIKE THIS, HOW DOES IT WORK. dO YOU SEND YOUR ECU AWAY TO BE MODIFIED,sorry about caps.
|
osti33
Needs a job
Posts: 2973
|
posted November 27, 2006 08:41 PM
quote:
WHO DOES A PROCEDURE LIKE THIS, HOW DOES IT WORK. dO YOU SEND YOUR ECU AWAY TO BE MODIFIED,sorry about caps.
DaveO does it (I'm sure other people do it too) and yes you send him your ECU.
|
entropy
Moderator
Posts: 8671
|
posted November 27, 2006 08:54 PM
i like 62-65psi seat pressure, yep!
____________
This moderator uses moderation in moderation
|
DrRyanScarsella
Expert Class
Posts: 113
|
posted November 28, 2006 05:01 AM
I remember him from Maxton, how do you contact him?
|
entropy
Moderator
Posts: 8671
|
posted November 28, 2006 09:20 AM
quote:
I remember him from Maxton, how do you contact him?
DrR,
1-5088020426, and tell him entropy sent ya (so i can get a discount next time  )
____________
This moderator uses moderation in moderation
|
TRNorBRN6001
Needs a job
Posts: 2021
|
posted November 28, 2006 08:22 PM
Yep Dave O is the man for the Job and I think Mad Mike has them Kwhightie springs for ya.
Most 12's HP tend to flatten out in that area so do not be to sad if it doesn't shoot right up to your new red line. It's a nice little buffer for nos or even lets us fat guys gear a touch lower.
____________
TFA 200MPH CLUB MEMBER!
|
VincentHill
Needs a life
Posts: 6520
|
posted November 29, 2006 02:33 AM
quote:
You better make sure to inform people that you'll need much stiffer valve springs!!! The stock springs are NOT to be trusted beyond 11,650rpm!!!! If you're going to extend the RPM's (especially up to 12,300rpm) you NEED to upgrade the springs. Oh, don't go with APE springs either.... peice of crap, no better than the stockers!
I begg to differ. Stock Springs are Progressive windings which make them soft to start at about 35 PSI Seat pressure and have very little room for increased valve lift before Coil Bind. The APE have about 55 Seat pressure and are not as severely (Read tightly ) made. The heavier the seat pressure the more the wear on the Cams and cam bearing surfaces which have no inserts so when they wear you replace the head. Also this additional pressure takes HP to operate. Springs are needed. APE Does not make the Best Spring in the world (Usually the Best Springs are made by Honda which we cannot get) but if anyone here had ever had or heard of a failure of their spring, it would have been reported
|
Phantom Menace
Expert Class
Posts: 169
|
posted November 29, 2006 12:18 PM
 Edited By: Phantom Menace on 29 Nov 2006 12:21
.
|
Phantom Menace
Expert Class
Posts: 169
|
posted November 29, 2006 12:21 PM
I don't know Mr. Hill, I thought the entire idea was to use a spring with more seat pressure than required so that when the springs gradually weaken over time... you're still SAFE and doesn't blow.
I know I'm not going to trust some worn stock 35lb valve springs on a 12,300rpm engine....
|
VincentHill
Needs a life
Posts: 6520
|
posted November 29, 2006 12:30 PM
quote:
I don't know Mr. Hill, I thought the entire idea was to use a spring with more seat pressure than required so that when the springs gradually weaken over time... you're still SAFE and doesn't blow.
I know I'm not going to trust some worn stock 35lb valve springs on a 12,300rpm engine....
That was not what the Difference was about. You stated that there was no difference between the APE and stock Spring. Both were just as bad! 20 Pounds more of Seat Pressure and about 0.200" more valve lift is a difference to me!
|
|
|
HOME
NEW TOPIC