Notices
GM Engine & Exhaust Performance EFI | GEN I/GEN II/GEN III/GEN IV Engines |Small Block | Big Block |
Sponsored by:
Sponsored by:

New rev limit?

Thread Tools
 
Search this Thread
 
Old 01-15-2007, 08:10 AM
  #1  
TECH Enthusiast
Thread Starter
 
GMC_DUDE's Avatar
 
Join Date: Dec 2003
Location: Western WA
Posts: 572
Likes: 0
Received 0 Likes on 0 Posts
Question New rev limit?

Wrapping up my latest mods: Katech rod bolts, LPE GT2-3 cam, new lifters (Comp Cams OEM), hardened push rods, yellow LS6 springs, new timing chain (OEM), and a Yank TT3000 all on a 4.8 with a Radix. So assuming everything works, what can I safely rev to now?
Old 01-15-2007, 09:18 AM
  #2  
TECH Senior Member
iTrader: (1)
 
Flyer's Avatar
 
Join Date: Jan 2003
Location: Armpit of East TX
Posts: 9,342
Likes: 0
Received 0 Likes on 0 Posts
Default

I would be more worried about spinning the blower to fast than the engine. I don't see a reason you couldn't hit 6500-6700. I dunno what the specs are on the cam though. If the lift is to high, I wouldn't advise that, but it will work.
Old 01-15-2007, 09:27 AM
  #3  
TECH Resident
iTrader: (10)
 
Bowtie70SS's Avatar
 
Join Date: Oct 2005
Location: Cincinnati, Ohio
Posts: 948
Likes: 0
Received 0 Likes on 0 Posts
Default

Once you start pushing the Radix past 56-5800 the amount of heat generated from the supercharger starts to overcome any additional gain in power. I would say you could spin 62-6500 with no problem or damage to the bottom end as long as the tune is correct.


Dave
Old 01-15-2007, 12:02 PM
  #4  
TECH Enthusiast
Thread Starter
 
GMC_DUDE's Avatar
 
Join Date: Dec 2003
Location: Western WA
Posts: 572
Likes: 0
Received 0 Likes on 0 Posts
Default

I'm not worried about the blower as that is something I can measure and adjust for. What I am thinking is that since the valvetrain and connecting rod bolts have been beefed up I should be able to get a few more rpm's before something lets loose. Any idea as to what the new limit would be?
Old 01-15-2007, 12:48 PM
  #5  
Baltimore Whore
iTrader: (95)
 
Mangled03gmc's Avatar
 
Join Date: Apr 2004
Location: In a van DOWN BY THE RIVER
Posts: 16,820
Likes: 0
Received 2 Likes on 2 Posts
Default

So your asking, disreguarding what the blower does or the extra heat it will put out is what rpm the motor alone is good too??? If that the case 6600-7000, but like they said spinning the blower that fast will cause more heat and wouldn't be making any more power at 7000 then it would make at 5800 or so..

John
Old 01-15-2007, 02:20 PM
  #6  
what a rush!
iTrader: (8)
 
moregrip's Avatar
 
Join Date: Feb 2004
Location: Las Vegas, NV
Posts: 17,610
Received 28 Likes on 20 Posts
Default

depends on what blower pulley he's using, I see a 4.8 in the sig so I don't see high rpm as being a problem for the blower or engine, I'd say 6500rpm-ish
Old 01-15-2007, 03:32 PM
  #7  
TECH Enthusiast
Thread Starter
 
GMC_DUDE's Avatar
 
Join Date: Dec 2003
Location: Western WA
Posts: 572
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by moregrip
depends on what blower pulley he's using, I see a 4.8 in the sig so I don't see high rpm as being a problem for the blower or engine, I'd say 6500rpm-ish
Give this man a cigar!! OK a beer would be healthier. Yes, I am running a 3.25" pulley which gives me 10 psi max boost. This works out to a max. Radix speed of 14800 rpm at 6500 engine rpm. Probably not the most efficient speed, true, but now I know where to set my rev limiter. Shift points will probably be around 6100 or so. Thanks Grip!
Old 01-15-2007, 09:01 PM
  #8  
TECH Senior Member
iTrader: (1)
 
Flyer's Avatar
 
Join Date: Jan 2003
Location: Armpit of East TX
Posts: 9,342
Likes: 0
Received 0 Likes on 0 Posts
Default

You can see where it wants to shift be looking at your logs. Log the gms/cyl PID and you will see it peak and start to fall back down. Once it starts to fall back down, you should shift soon after that, the fall means the motor is not making any more power and is beginning to loose power.

I htink you are mistaken connecting rods for pushrods though. Pushrods are in the valvetrain, connecting rods connect the piston to the crankshaft.
Old 01-15-2007, 09:17 PM
  #9  
Banned
iTrader: (4)
 
litreddevil's Avatar
 
Join Date: Oct 2003
Location: From Houma La. Living n Ellisville Miss.
Posts: 5,151
Likes: 0
Received 1 Like on 1 Post
Default

so did you get the answer you were looking for
Old 01-15-2007, 11:58 PM
  #10  
TECH Enthusiast
Thread Starter
 
GMC_DUDE's Avatar
 
Join Date: Dec 2003
Location: Western WA
Posts: 572
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by litreddevil
so did you get the answer you were looking for
Yes I did. Thanks to everyone for the replies.


Quick Reply: New rev limit?



All times are GMT -5. The time now is 08:29 PM.