LT1-LT4 Modifications 1993-97 Gen II Small Block V8

Higher Revving LT1?

Thread Tools
 
Search this Thread
 
Old 06-15-2008, 09:32 AM
  #1  
Launching!
Thread Starter
 
OneBadTA's Avatar
 
Join Date: Jun 2008
Location: Glen Rock, PA
Posts: 242
Likes: 0
Received 0 Likes on 0 Posts
Default Higher Revving LT1?

Just bought a 96 TA A4. Plans is to build it up some but keep it NA. I love the car but dont like the rev limiter. If i build the head with a solid lifter setup, can i get this to rev out to 6500rpm fairly safe without touching the bottom end? Im not too familier with the LT1 engines yet but asking because my dad ran solid lifters on his old 327 small block w/ 283 heads and he was able to rev that out to 7krpm and never touching the bottom end. Didnt know if the LT1 can do it too.
Old 06-15-2008, 10:39 AM
  #2  
TECH Resident
iTrader: (9)
 
Pro_built7's Avatar
 
Join Date: Dec 2007
Posts: 883
Likes: 0
Received 0 Likes on 0 Posts
Default

I'd say 6500 is asking alot of your stock lt1 bottom end, I wouldn't expect it to last too long
Old 06-15-2008, 10:48 AM
  #3  
TECH Regular
iTrader: (4)
 
projekt70chevelle's Avatar
 
Join Date: Mar 2006
Posts: 479
Likes: 0
Received 0 Likes on 0 Posts
Default

Really depends on mileage and condition of the bottom end. 6500 is about the grey zone. Some people are fine for a long time, and some people trash their bottom end the first time they hit it. If its not your daily then you should be fine for a while, but there is no guarantee.

It wouldn't hurt to tear it down check your clearances, throw in some new bearings, and get it rebalanced. If you are staying N/A you might wanna go with some light weight hyperuetectic pistons with a higher compression. Then again you may wanna look at forged depending on how crazy your going with it, but that will increase rotating mass (unless you spend big bucks on some lightweight ones).
Old 06-15-2008, 10:49 AM
  #4  
Launching!
Thread Starter
 
OneBadTA's Avatar
 
Join Date: Jun 2008
Location: Glen Rock, PA
Posts: 242
Likes: 0
Received 0 Likes on 0 Posts
Default

What typically goes out at those RPM's?
Old 06-15-2008, 10:52 AM
  #5  
TECH Senior Member
iTrader: (26)
 
kinglt-1's Avatar
 
Join Date: Jul 2005
Location: Ft. Wayne, IN
Posts: 5,794
Received 196 Likes on 138 Posts

Default

rod bearings.
Old 06-15-2008, 11:07 AM
  #6  
10 Second Club
iTrader: (8)
 
355z28's Avatar
 
Join Date: Oct 2007
Location: Iowa
Posts: 1,249
Likes: 0
Received 2 Likes on 2 Posts

Default

mines been overhauled, but i turn 6600 rpm quite often with stock crank, stock rod, stock rod bolts, and federal mogul OEM replacement bearings.

its kinda of russianroulet with the stock bottom end. Some get away turning 6500-7000 rpm and never have it fail on them. Some grenade the bottom end taking it up to 6000 rpm on the stock rev limiter.

Basically what im saying is theres no good answer to your question, your either lucky or your not.
Old 06-15-2008, 11:18 AM
  #7  
Launching!
Thread Starter
 
OneBadTA's Avatar
 
Join Date: Jun 2008
Location: Glen Rock, PA
Posts: 242
Likes: 0
Received 0 Likes on 0 Posts
Default

alright thanks guys. i think ill give it a try. probably put a larger oil pan on so the oil stays cooler which should help the bearings.
Old 06-15-2008, 11:20 AM
  #8  
TECH Regular
iTrader: (4)
 
projekt70chevelle's Avatar
 
Join Date: Mar 2006
Posts: 479
Likes: 0
Received 0 Likes on 0 Posts
Default

Are you keeping the stock 4L60 in there? I don't think they take higher rpms too well at all.
Old 06-15-2008, 11:22 AM
  #9  
Banned
iTrader: (22)
 
LS1 SPEED's Avatar
 
Join Date: Jan 2004
Location: Schaumburg,IL
Posts: 4,957
Likes: 0
Received 0 Likes on 0 Posts
Default

I have had 2 LT's which have seen 6500+ and the 1 now has about 90K on the short with no issues

I would also keep it a hydraulic cam and many have been proven to do very well with the proper valvetrain setup.
Old 06-15-2008, 11:25 AM
  #10  
10 Second Club
iTrader: (8)
 
TwoFast4Lv's Avatar
 
Join Date: Nov 2001
Location: LT1 land...the "409" of the 90s!
Posts: 10,023
Received 6 Likes on 5 Posts

Default

Larry is spot on IMHO. My old Junk yard engine spent lots of time at 6,000-6,800
Old 06-15-2008, 11:29 AM
  #11  
Launching!
Thread Starter
 
OneBadTA's Avatar
 
Join Date: Jun 2008
Location: Glen Rock, PA
Posts: 242
Likes: 0
Received 0 Likes on 0 Posts
Default

Yea ill be keeping the stock 4l60e in. probably just do a 2800 or 3500 stall. do they 4l60's have tranny coolers on them? only reason i can think of them going out at high rpm is from the fluid getting overheated.
Old 06-15-2008, 11:45 AM
  #12  
TECH Addict
iTrader: (12)
 
Turnin20s's Avatar
 
Join Date: Mar 2007
Posts: 2,468
Likes: 0
Received 0 Likes on 0 Posts
Default

My rev limiter is set at 7000 rpms now. I have a CC306 cam and all of the proper springs to take the lift and rpms. My bottom end is basically stock.....stock crank, studded main caps, stock rods with ARP bolts, and 11.1:1 compression forged pistons. My block has been align honed since the studs were added and the rods resized for the ARP bolts. I used to have the limiter set at 6800, but when I had my reflash for the M6 I had Ion bump it up to 7K. My tranny didn't last at all behind my new motor, well it did for about 200 miles and it shifted perfectly before I blew the motor up.

But on another note I do not think the stock heads are up to par for some 7k pulls. I may be wrong, but I didn't think the stockers flowed enough to go over 6500. I have LE3 heads on my car and they are great. Also the LT1 motors are factory roller cam motors. You would have to change over to a solid roller cam and also change the pushrods and the valve springs accordingly. I think you need alot more mods before you go and throw a solid roller cam at your motor, but thats just my opinion.

What else is done to the car? Headers, suspension, CAI, anything besides the catback?
Old 06-15-2008, 12:01 PM
  #13  
Launching!
Thread Starter
 
OneBadTA's Avatar
 
Join Date: Jun 2008
Location: Glen Rock, PA
Posts: 242
Likes: 0
Received 0 Likes on 0 Posts
Default

I already know i need alot more mods done. Hell, i just bought the car a couple days ago. Im just asking if its possible. Most likely going with trickflow heads, ported intake, and definitly do the solid setup with proper valvetrain. I run a full solid lifter setup in my SR20 and love it. The 270 duration solid cams made about 20whp in the top end while giving more tq in the midrange over the 270 duration hydraulic lash setup. Took an engine that used to redline at 7500rpm and now redlines at 9krpm. I mainly want solids just so its one less thing to worry about failing. Last thing i want is the lifters to float from lack of oil causing the valves to stay open and get smashed by the pistons.
Old 06-15-2008, 12:19 PM
  #14  
TECH Senior Member
iTrader: (3)
 
Formula350's Avatar
 
Join Date: Oct 2006
Location: Decatur, TN (N-W of Athens)
Posts: 7,564
Likes: 0
Received 3 Likes on 3 Posts
Default

As most have said, you can, but beware it may give out. 6,300 (I'd do 6,200 to be safe) is about the max for extended periods. If you want to freshen up bearings, it'll probably do 6,500.

The 700R4s (93) and 4L60Es all have trans coolers. I don't know if even the 3rd Gens were w/o a cooler (at least for 305s/350s in later years). An aftermarket one couldn't hurt though since it, oil, and coolant share the poor radiator heh.

I didn't notice you mentioning the mileage though, so even the tranny might need a refresh :\ Hell, it wouldn't hurt to do it now if you do plan to spice up the motor. Get the Sonnax stuff if you do though, quality parts and lots of nice upgrades available.

bulkpart.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=2&Category_Cod e=4L60E-4L65E

(Just add the usual stuff to make it a link. A mod said non-sponsor links missing part of the link is safe.)
Old 06-15-2008, 12:30 PM
  #15  
Launching!
Thread Starter
 
OneBadTA's Avatar
 
Join Date: Jun 2008
Location: Glen Rock, PA
Posts: 242
Likes: 0
Received 0 Likes on 0 Posts
Default

Engines got about 137k miles on. With the shift kit, the trans shifts very firm. Firm enough to chirp 2nd at higher rpm. Im gonna do a compression test on it next weekend probably. It runs great though. Doesnt burn or leak any oil. No knocks or taps at all and has around 40psi oil pressure at startup.
Old 06-15-2008, 12:34 PM
  #16  
TECH Senior Member
iTrader: (3)
 
Formula350's Avatar
 
Join Date: Oct 2006
Location: Decatur, TN (N-W of Athens)
Posts: 7,564
Likes: 0
Received 3 Likes on 3 Posts
Default

I'm going to add this, that I stumbled upon (since my trans is shot)

"Auxiliary coolers are just that, in addition to. Water cools 32 times better (faster) than air always, period."

Not that you didn't know this, but for any other readers out there. So if you do add a air trans cooler, do it in conjunction with the stock one. Run it through one, then the other (either rad first or air first) and back to the trans. Can't be too safe

My stock one shifts firm enough to heavily chirp my 255 DRs into 2nd :S Poor trans, DRs probably blew it up just from street driving lol
Old 06-15-2008, 05:04 PM
  #17  
TECH Fanatic
iTrader: (10)
 
zlover129's Avatar
 
Join Date: May 2005
Location: Charlotte, NC
Posts: 1,197
Likes: 0
Received 0 Likes on 0 Posts
Default

mine is a rebuilt stock bottom end and i shift usually anywhere from 6400-6600 (no shift light and well i don't look at the tach when im on it). I try not to beat on it too much...but its kinda like crack
Old 06-15-2008, 05:14 PM
  #18  
Launching!
Thread Starter
 
OneBadTA's Avatar
 
Join Date: Jun 2008
Location: Glen Rock, PA
Posts: 242
Likes: 0
Received 0 Likes on 0 Posts
Default

Nice. You all pretty much answered my question. Proceede with caution. Ive been warned and ill probably do it anyway. lol. Thanks everyone.

Last edited by OneBadTA; 06-15-2008 at 05:21 PM.
Old 06-15-2008, 10:36 PM
  #19  
TECH Addict
iTrader: (12)
 
Turnin20s's Avatar
 
Join Date: Mar 2007
Posts: 2,468
Likes: 0
Received 0 Likes on 0 Posts
Default

Hey sorry if I came off like a dick, I really didn't mean for it to sound like that. I didn't really reread over it until now.

But with a stock bottom end I'd say yank the motor out when you do the heads, it will make your life so much easier. If I would have done that I would have saved alot of back ach and frustration and it would have got done alot faster. You already have to unhook all of your electrical anyways and its only about 10 more bolts to yank the whole motor out, but thats just my opinion.

But I'm planning on some new heads and a solid roller setup and probably a single plane conversion in the next few years, but I'll have to see. Good luck with the setup and just do your homework and you will be fine, just remember that the stock PCM runs out of RPM at about 7200 rpms right, I can't remember
Old 06-15-2008, 11:25 PM
  #20  
TECH Senior Member
iTrader: (3)
 
Formula350's Avatar
 
Join Date: Oct 2006
Location: Decatur, TN (N-W of Athens)
Posts: 7,564
Likes: 0
Received 3 Likes on 3 Posts
Default

Originally Posted by Turnin20s
Hey sorry if I came off like a dick, I really didn't mean for it to sound like that. I didn't really reread over it until now.

But with a stock bottom end I'd say yank the motor out when you do the heads, it will make your life so much easier. If I would have done that I would have saved alot of back ach and frustration and it would have got done alot faster. You already have to unhook all of your electrical anyways and its only about 10 more bolts to yank the whole motor out, but thats just my opinion.

But I'm planning on some new heads and a solid roller setup and probably a single plane conversion in the next few years, but I'll have to see. Good luck with the setup and just do your homework and you will be fine, just remember that the stock PCM runs out of RPM at about 7200 rpms right, I can't remember


We know you're a dick anyways, so don't worry JK



Quick Reply: Higher Revving LT1?



All times are GMT -5. The time now is 07:41 AM.