TBI Throttle Body Injection discussion and questions. L03/CFI tech and other performance enhancements.

L03 mods

Thread Tools
 
Search this Thread
 
Old 06-10-2019, 01:51 PM
  #1  
Junior Member
Thread Starter
 
chris004's Avatar
 
Join Date: Jun 2019
Location: Wisconsin
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Car: 1991 Camaro RS
Engine: 305 T.B.I.
Transmission: 700r4
L03 mods

Hey guys, I would like to know what a good set of heads for the L03 is. I am going to rebuild the engine after having it bored .030" over. I will also be giving it a better camshaft, but still use the throttle body intake. No, I do not want to get a 350 as I want to keep some of the originality to the car. I will be getting the Edelbrock 3704 performer intake as well. As for the crankshaft, what do you guys think of Eagle Specialty Products? Oh and I almost forgot to mention that I will be getting headers.
Old 06-10-2019, 04:35 PM
  #2  
Supreme Member

iTrader: (2)
 
dmccain's Avatar
 
Join Date: Mar 2014
Location: South Ms
Posts: 4,417
Received 720 Likes on 490 Posts
Car: 89 Firebird
Engine: 355 TBI
Transmission: 700R4
Axle/Gears: 10 Bolt.Posi-3.73s
Re: L03 mods

L98 cam, 081 TPI heads. Great idea to address the puny exhaust with a set of headers, y-pipe, and 3in exhaust will do wonders. Then drop a S10 torque converter, 3.42s and put in a shift kit you will have a lot better driving experience. I wouldn't spend a ton on a 305 so these mods are relatively cheap and will go over good with a 350 when you get bored of it.
Old 06-10-2019, 10:55 PM
  #3  
Junior Member
Thread Starter
 
chris004's Avatar
 
Join Date: Jun 2019
Location: Wisconsin
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Car: 1991 Camaro RS
Engine: 305 T.B.I.
Transmission: 700r4
Re: L03 mods

Originally Posted by dmccain
L98 cam, 081 TPI heads. Great idea to address the puny exhaust with a set of headers, y-pipe, and 3in exhaust will do wonders. Then drop a S10 torque converter, 3.42s and put in a shift kit you will have a lot better driving experience. I wouldn't spend a ton on a 305 so these mods are relatively cheap and will go over good with a 350 when you get bored of it.
As far as those TPI heads go. How much modifying the engine is required to put them on? Will they bolt right up to the block and manifold? And as for the L98 camshaft...will I have to get a chip for the ecm?
Old 06-10-2019, 11:07 PM
  #4  
Supreme Member

 
Schurkey's Avatar
 
Join Date: Feb 2011
Posts: 1,512
Received 72 Likes on 56 Posts
Re: L03 mods

305 is a waste of effort. Read this thread:
https://www.thirdgen.org/forums/tbi/...ost-power.html
Old 06-11-2019, 07:20 AM
  #5  
Supreme Member

iTrader: (2)
 
dmccain's Avatar
 
Join Date: Mar 2014
Location: South Ms
Posts: 4,417
Received 720 Likes on 490 Posts
Car: 89 Firebird
Engine: 355 TBI
Transmission: 700R4
Axle/Gears: 10 Bolt.Posi-3.73s
Re: L03 mods

Originally Posted by Schurkey
305 is a waste of effort. Read this thread:
https://www.thirdgen.org/forums/tbi/...ost-power.html
I totally agree. If you are happy underpowered and just cruising and sounding the part.. a 305 is ok. I will never again rebuild one or try to enhance one in any way again myself.
Old 06-11-2019, 11:01 AM
  #6  
Junior Member
Thread Starter
 
chris004's Avatar
 
Join Date: Jun 2019
Location: Wisconsin
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Car: 1991 Camaro RS
Engine: 305 T.B.I.
Transmission: 700r4
Re: L03 mods

Originally Posted by dmccain
I totally agree. If you are happy underpowered and just cruising and sounding the part...a 305 is ok. I will never again rebuild one or try to enhance one in any way again myself.
I am perfectly content with a 305 rebuild as it is fairly cheap and it is just a daily driver. Nothing to show off.
Old 06-11-2019, 01:04 PM
  #7  
Supreme Member

iTrader: (167)
 
John in RI's Avatar
 
Join Date: Aug 1999
Location: RI
Posts: 5,018
Received 348 Likes on 263 Posts
Car: 1984 Camaro Berlinetta
Engine: LT1
Transmission: T56 6-speed
Axle/Gears: 4.11 LS1 Rear End
Re: L03 mods

Will they bolt right up to the block and manifold?
Yup.


Old 06-11-2019, 02:22 PM
  #8  
Supreme Member

iTrader: (2)
 
dmccain's Avatar
 
Join Date: Mar 2014
Location: South Ms
Posts: 4,417
Received 720 Likes on 490 Posts
Car: 89 Firebird
Engine: 355 TBI
Transmission: 700R4
Axle/Gears: 10 Bolt.Posi-3.73s
Re: L03 mods

Originally Posted by chris004
As far as those TPI heads go. How much modifying the engine is required to put them on? Will they bolt right up to the block and manifold? And as for the L98 camshaft...will I have to get a chip for the ecm?
The cam will work fine with the ECM ive read of numerous people doing it and it will definitely give it a boost. A custom chip would help though, talk with Brian @ Tuned Performance here on the boards I highly recommend him stand up guy.
Old 06-12-2019, 10:53 PM
  #9  
Junior Member
Thread Starter
 
chris004's Avatar
 
Join Date: Jun 2019
Location: Wisconsin
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Car: 1991 Camaro RS
Engine: 305 T.B.I.
Transmission: 700r4
Re: L03 mods

Originally Posted by dmccain
The cam will work fine with the ECM ive read of numerous people doing it and it will definitely give it a boost. A custom chip would help though, talk with Brian @ Tuned Performance here on the boards I highly recommend him stand up guy.
How do I get into contact with him? I am a little new to this forum site
Old 06-13-2019, 01:27 AM
  #10  
Member

iTrader: (1)
 
morgsie's Avatar
 
Join Date: Feb 2008
Posts: 454
Received 6 Likes on 6 Posts
Re: L03 mods

Originally Posted by chris004
I am perfectly content with a 305 rebuild as it is fairly cheap and it is just a daily driver. Nothing to show off.
hah. cost of rebuilding a 305 is no different than a 350. i just went through this with my truck engine (originally a tbi 350). it is hands down cheaper to buy a crate engine. i merely rebuilt mine for "bragging rights". rebuilding a engine is by no means "cheap".

If you MUST keep the 305 (been there done that, no thanks) there's always the option of a vortec 305 out of a late 90s truck or express van.
Old 06-13-2019, 05:35 AM
  #11  
Senior Member

iTrader: (5)
 
ownor's Avatar
 
Join Date: Sep 2006
Location: Austria
Posts: 951
Likes: 0
Received 2 Likes on 2 Posts
Car: 84 TA / 89 Formula
Engine: LS1 / L03
Transmission: T56 / 700R4
Axle/Gears: 3.73 / 3.27
Re: L03 mods

Originally Posted by dmccain
L98 cam, 081 TPI heads. Great idea to address the puny exhaust with a set of headers, y-pipe, and 3in exhaust will do wonders. Then drop a S10 torque converter, 3.42s and put in a shift kit you will have a lot better driving experience. I wouldn't spend a ton on a 305 so these mods are relatively cheap and will go over good with a 350 when you get bored of it.
i agree on the full exhaust and gears as mentioned here. that really woke mine up anyways, i also added an EBL later to do some tuning for nicer driveability and power but also because i found it very interesting insight.
Old 08-05-2019, 01:21 PM
  #12  
Supreme Member

 
Tom 400 CFI's Avatar
 
Join Date: Oct 2000
Location: Park City, UT
Posts: 1,871
Received 263 Likes on 183 Posts
Car: '92 Corvette
Engine: LT1
Transmission: ZF6
Axle/Gears: 3.45
Re: L03 mods

Originally Posted by chris004
I want to keep some of the originality to the car.
Originally Posted by Schurkey
305 is a waste of effort. Read this thread:
https://www.thirdgen.org/forums/tbi/...ost-power.html
Totally.

Nobody GAF about the "originality" of most 3rd gens...and even less about one having a 305 vs a 350, unless you got some rare 1LE, 305, 5-speed car. You don't, so don't shoot yourself in the foot by getting hung up on worthless 305's.

Also, what crank? Why? No 305 TBI is going to make enough power to warrant a crank swap of any kind. Stock crank is way better than good enough.
Old 08-08-2019, 05:35 PM
  #13  
Member
iTrader: (1)
 
Sweatlock's Avatar
 
Join Date: Jul 2017
Posts: 125
Received 11 Likes on 10 Posts
Re: L03 mods

Once it’s under the hood, no one is going to be able to tell a 350 from a 305. And probably won’t care.

You can tell everyone it’s a 305, if it makes you feel better.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
bear88ss
TBI
2
10-12-2009 01:09 PM
pascal_91ta
Theoretical and Street Racing
12
05-24-2008 07:07 PM
Abubaca
Suspension and Chassis
6
07-26-2004 10:55 AM
Joe_L
TBI
2
02-23-2004 08:30 PM



Quick Reply: L03 mods



All times are GMT -5. The time now is 09:02 AM.