LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

Injector size?????

Thread Tools
 
Search this Thread
 
Old 09-14-2004, 09:53 PM
  #1  
Registered User
Thread Starter
 
WS6NIGHTMARE's Avatar
 
Join Date: Jun 2004
Location: Webster,Tx
Posts: 546
Injector size?????

If I put 32# injectors on an LT1 with just a full exhaust, it should be ok right?
I know that will require a PCM tune at a minimum, but I am about to get that done anyway, but that should be all it needs to work fine?
WS6NIGHTMARE is offline  
Old 09-15-2004, 10:01 AM
  #2  
Registered User
 
unvc92camarors's Avatar
 
Join Date: Jul 2003
Location: cinci
Posts: 3,772
Re: Injector size?????

question: what are you doing that you need 32s? preparing for a cam/heads project?
and i'm not exactly sure of the answer but, i would suggest searching for a quick answer
i thought i remembered seeing a thread about this a while back

ttt for ya tho
unvc92camarors is offline  
Old 09-15-2004, 02:11 PM
  #3  
Registered User
 
TransAmGT94's Avatar
 
Join Date: Feb 2004
Location: Evansville
Posts: 310
Re: Injector size?????

If you are planning on changing other stuff down the road make sure you put large enough injectors in now to feed it down the road no point in paying out the $$$ twice A good tune will make any injectors work on your set up as long as you dont go way out of reason
TransAmGT94 is offline  
Old 09-15-2004, 03:39 PM
  #4  
Registered User
Thread Starter
 
WS6NIGHTMARE's Avatar
 
Join Date: Jun 2004
Location: Webster,Tx
Posts: 546
Re: Injector size?????

Thanks guys. The reason i was considering those was because..
1. I am planning a heads/cam package later on (but you know how those go)
2. Somebody was selling them for a good deal ($125)
3. About to send my computer to get tuned anyway

I decided to just order the 25# injectors from SLP since the guy selling the 32# didnt know what they were. Its not a good deal if I have to pay more money for alot of guess work later on. Besides, for only $100, I can replace them again later if needed.
WS6NIGHTMARE is offline  
Old 09-15-2004, 04:46 PM
  #5  
Registered User
 
joebeemish's Avatar
 
Join Date: Apr 2004
Location: thousand oaks, calif
Posts: 116
Re: Injector size?????

Why are you going with 25#? 24# is stock. Are the originals broken? A rule of thumb is that 24# will support up to 310 Crank HP. You can do the math for your target HP based on that ratio. For example, if your target Crank Hp is 500, you would want at least 39# injectors.
joebeemish is offline  
Old 09-15-2004, 04:49 PM
  #6  
Registered User
Thread Starter
 
WS6NIGHTMARE's Avatar
 
Join Date: Jun 2004
Location: Webster,Tx
Posts: 546
Re: Injector size?????

Did I fail to mention I have an LT1? No wait, I did post this in LT1 Tech right? Stock as far as I know is 19#.
WS6NIGHTMARE is offline  
Old 09-15-2004, 04:59 PM
  #7  
Registered User
 
amean94ta's Avatar
 
Join Date: Jul 2003
Location: pa
Posts: 1,991
Re: Injector size?????

wait 36 lbs is good for 600 crank hp then how are 39 lb good for 500 that dont make sence
amean94ta is offline  
Old 09-15-2004, 05:13 PM
  #8  
Registered User
 
97Z-M6's Avatar
 
Join Date: Mar 2002
Location: near waco tx.
Posts: 2,058
Re: Injector size?????

Originally Posted by WS6NIGHTMARE
Did I fail to mention I have an LT1? No wait, I did post this in LT1 Tech right? Stock as far as I know is 19#.
seeing that your name is ws6XXXXXX and they didnt make the ws6 until after 93 that i know of. that means you have 24# injectors stock. and they will support 340rwhp. and you also need to know what kind the new injectors are and what they are flowed at. becuase if they are 25# at 50 psi they would acctually be smaller than your stock 24# so you need to know what your buying, and the pcm will not correct for different size injectors. and you could possiblly ruin your engine.

sounds like a waste of money for 25# injectors but its your money.
97Z-M6 is offline  
Old 09-15-2004, 05:44 PM
  #9  
Registered User
 
SS MPSTR's Avatar
 
Join Date: Oct 2001
Location: SoCal
Posts: 2,525
Re: Injector size?????

I've got 42's for 580HP.
SS MPSTR is offline  
Old 09-15-2004, 06:07 PM
  #10  
Registered User
 
TransAm-Z's Avatar
 
Join Date: Jun 2004
Posts: 102
Re: Injector size?????

Originally Posted by joebeemish
Why are you going with 25#? 24# is stock. Are the originals broken? A rule of thumb is that 24# will support up to 310 Crank HP. You can do the math for your target HP based on that ratio. For example, if your target Crank Hp is 500, you would want at least 39# injectors.

Originally Posted by 97Z-M6
seeing that your name is ws6XXXXXX and they didnt make the ws6 until after 93 that i know of. that means you have 24# injectors stock. and they will support 340rwhp. and you also need to know what kind the new injectors are and what they are flowed at. becuase if they are 25# at 50 psi they would acctually be smaller than your stock 24# so you need to know what your buying, and the pcm will not correct for different size injectors. and you could possiblly ruin your engine.

sounds like a waste of money for 25# injectors but its your money.

Does anyone else see the decrepency??? So will 24# injectors support 310 FWHP or 340 RWHP. I need to know cause I will be starting up my new motor in about a month and for now have the stock injectors. The motor is a 355 with the hot cam, AI econo-ported heads, with stock TB, and Stock manifolds.

Thanks
TransAm-Z is offline  
Old 09-15-2004, 06:32 PM
  #11  
Registered User
 
joebeemish's Avatar
 
Join Date: Apr 2004
Location: thousand oaks, calif
Posts: 116
Re: Injector size?????

Based on some "standard" formulas out there (80% duty cycle, etc) The stock 24# injector will support 310 crank HP. You can push them harder, but if you search for fuel injector formulas, the math says 310 HP. The stock motor is 275 HP. I went to 42# injectors because my target HP is 400 RWHP/ 500 crank HP. (approx). Again, if you are not pushing the engine too far, stay with the stock injectors.
joebeemish is offline  
Old 09-15-2004, 06:55 PM
  #12  
Registered User
 
joebeemish's Avatar
 
Join Date: Apr 2004
Location: thousand oaks, calif
Posts: 116
Re: Injector size?????

see
http://www.rceng.com/technical.htm
joebeemish is offline  
Old 09-15-2004, 08:19 PM
  #13  
Registered User
 
97Z-M6's Avatar
 
Join Date: Mar 2002
Location: near waco tx.
Posts: 2,058
Re: Injector size?????

stock injectors aregood for 340rwhp. madwolf ( does tuning for a living) and proved it on a dyno.

there is no discrepency if it will suport 340 rwhp it will also suport 310 fwhp.

if you want the dam injectors buy them, sounds like you have your mind made up anyway.
97Z-M6 is offline  
Old 09-15-2004, 08:29 PM
  #14  
Registered User
 
TransAm-Z's Avatar
 
Join Date: Jun 2004
Posts: 102
Re: Injector size?????

Originally Posted by joebeemish
Based on some "standard" formulas out there (80% duty cycle, etc) The stock 24# injector will support 310 crank HP. You can push them harder, but if you search for fuel injector formulas, the math says 310 HP. The stock motor is 275 HP. I went to 42# injectors because my target HP is 400 RWHP/ 500 crank HP. (approx). Again, if you are not pushing the engine too far, stay with the stock injectors.

My target is about 375 FWHP I think that's about all I'll see with the stock manifolds. So if I run the 24 lb injectors to break the motor in... how is this gonna effect me? I just don't get a good grasp on what a reprogramed engine will do? Will the injectors be fine for lower RPM's and lean out at high RPM's or will it lean out through the entire range?
TransAm-Z is offline  
Old 09-15-2004, 08:51 PM
  #15  
Registered User
 
Houdini's Avatar
 
Join Date: Sep 2001
Location: Massachusetts
Posts: 175
Re: Injector size?????

I'm running my stock injectors at 390 rwhp.......... think they might be maxed out.
Houdini is offline  


Quick Reply: Injector size?????



All times are GMT -5. The time now is 08:27 PM.