Notices
Scion tC 1G Forced Induction Turbo and supercharger applications...

Increasing Rev Limit

Thread Tools
 
Search this Thread
 
Old Jan 5, 2011 | 05:42 PM
  #1  
thendawg's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (2)
 
Joined: May 2008
Posts: 2,720
Default Increasing Rev Limit

Soooo, Ive decided to build another motor and keep the tc The insurance money is more than enough so Ill be able to pretty much do whatever I want BTW for those of you who didnt know, on Christmas night I hit a piece of rebar about 4' long going about 75-80mph - it went through the radiator and put a hole in my shortblock I was originally going to sell the car and try to make as much money as I can, but Ive decided Ive got too much in it too let it go for cheap, and Id rather rebuild

Heres my question, can I safely rev the motor to say 7200-7500rpm by simply upgrading the valvesprings/retainers to the BC ones? I really dont want to mess with valve work, or cams if I dont have to. The only reason I want to rev it out further is really to make the gears a bit longer. (Of course Ill also be building the shortblock with Wiseco pistons and K1 rods - same I used in the last build)

Also second, should I expect to have to replace the buckets due to changing only the valvesprings? I would expect not, however I will still check the clearances, Im just wondering If I need to expect to replace them due to diff valvesprings changing the clearances or not.
Old Jan 5, 2011 | 07:55 PM
  #2  
tneely's Avatar
Senior Member
5 Year Member
SL Member
iTrader: (1)
 
Joined: Jan 2010
Posts: 122
From: Dexter, MI
Default

If you get the BC springs and retainers, I highly suggest you get their camshafts as well. I currently don't have the money for the cams, so I put my car back and found massive clearance issue. Suggested intake (or maybe exhaust) is about .25 clearance. After the springs, I had gaps up to .98. Toyota doesn't sell lifters that big, the closest is still .1 off suggested clearance. So, you must replace your cams eventually with the BC springs.
Old Jan 6, 2011 | 12:00 AM
  #3  
thendawg's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (2)
 
Joined: May 2008
Posts: 2,720
Default

Damn I was hoping Id be able to use the BC springs with stock cams but it sounds like no Anyone know if you can safely rev to 7000-7200rpm on stock springs/head?
Old Jan 6, 2011 | 01:47 AM
  #4  
tneely's Avatar
Senior Member
5 Year Member
SL Member
iTrader: (1)
 
Joined: Jan 2010
Posts: 122
From: Dexter, MI
Default

I don't know, you might be ok. Excessive clearance can lead to failure, loss of performance, and noisy clicking. However, the majority of my valves can be adjusted to proper clearance. The ones that are slightly off shouldn't be a huge issue, especially after the engine heats up and the metal expands. Also, the clearance on your engine may be better than mine, it varies. Maybe someone more knowledgable could elucidate on the subject.
Old Jan 6, 2011 | 02:12 AM
  #5  
pwee08's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (7)
 
Joined: Mar 2008
Posts: 1,593
From: Miami, FL
Default

WOOO for not getting rid of your tC
Old Jan 6, 2011 | 03:20 AM
  #6  
crush02342002's Avatar
Senior Member
10 Year Member

5 Year Member
SL Member
iTrader: (2)
 
Joined: Feb 2008
Posts: 11,271
From: Houston, TX
Default

congrats bro...looks like everyone is having some good luck in the new year!!!!!!! hope some of that rubs off on me...lol (no homo)
Old Jan 6, 2011 | 04:08 AM
  #7  
thendawg's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (2)
 
Joined: May 2008
Posts: 2,720
Default

So I tried calling BC about this today, didnt get a response, I will call em again tomm and see if they pickup
Old Jan 6, 2011 | 05:32 PM
  #8  
thendawg's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (2)
 
Joined: May 2008
Posts: 2,720
Default

Also... I read on a post quite awhile back, someone said they rev'd to 7200rpm on bone stock head without issue?
Old Jan 6, 2011 | 05:40 PM
  #9  
johnhawkins's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (1)
 
Joined: Oct 2008
Posts: 1,100
From: Buffalo, NY
Default

Originally Posted by thendawg
Damn I was hoping Id be able to use the BC springs with stock cams but it sounds like no Anyone know if you can safely rev to 7000-7200rpm on stock springs/head?
For stock head+block max revs should be around 7200-7300. After that, the stock cams wont make power.
Old Jan 6, 2011 | 06:46 PM
  #10  
thendawg's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (2)
 
Joined: May 2008
Posts: 2,720
Default

Hmm I just wonder if I can safely rev to 7k making 500whp on stock head
Old Jan 6, 2011 | 06:47 PM
  #11  
mmmpshh's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (5)
 
Joined: Aug 2009
Posts: 2,524
From: Oklahoma City From Brooklyn NYC
Default

^.... wonder if I can do it on the stock motor? lol
Old Jan 6, 2011 | 06:49 PM
  #12  
thendawg's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (2)
 
Joined: May 2008
Posts: 2,720
Default

DO it
Old Jan 6, 2011 | 06:55 PM
  #13  
mmmpshh's Avatar
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (5)
 
Joined: Aug 2009
Posts: 2,524
From: Oklahoma City From Brooklyn NYC
Default

lol... you know Im daring, done alot of crazy ish but that jus seems like a nuke waiting to go off. lol
Old Jan 7, 2011 | 03:11 AM
  #14  
thendawg's Avatar
Thread Starter
Senior Member
10 Year Member
5 Year Member
SL Member
iTrader: (2)
 
Joined: May 2008
Posts: 2,720
Default

Wish I could find out more about these springs... Cant seem to get ahold of BC Also, will the springs alone allow you to rev to 7200-7500? Or are there any issues with the buckets? (other than the aforementioned clearance issue)
Old Jan 21, 2011 | 07:58 PM
  #15  
andrew_ptuning's Avatar
Senior Member
SL Member
 
Joined: Jan 2011
Posts: 223
Default

Just so everyone knows the rev limit can not be raised in a 07-09 tc. Because the ecu will start to close the throttle body, and pull ignition timing as well.

-Drew
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
carid
Exclusive Sponsored Sales
3
Feb 10, 2019 10:46 PM
Subaru86
Scion FR-S ICE & Interior
0
Sep 10, 2015 08:11 AM
umnitza
Exclusive Sponsored Sales
1
Sep 1, 2015 08:06 PM
carid
Exclusive Sponsored Sales
0
Aug 31, 2015 11:17 AM
carid
Exclusive Sponsored Sales
0
Aug 7, 2015 11:32 AM




All times are GMT. The time now is 11:58 PM.