Search



Go Back   Third Generation F-Body Message Boards > Tech Boards > FAQ Board
Register Forgot Password?

FAQ Board This board is where some of the most informative and helpful Frequently Asked Questions we get here at ThirdGen.Org are put for easier reference. This IS NOT a general question board.

Welcome to ThirdGen.org!
Welcome to ThirdGen.org.

You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, join the ThirdGen.org community today!


Reply
 
Thread Tools Search this Thread
Old 09-28-2004, 02:45 PM   #1
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

Differences between 305 engines, performance tips

There was only one engine called "HO" in 3rd gens - the L69 (VIN code "G") from '83-'86. There seems to be a lot of confusion over what made it "HO", so here are some basics.

At least in 3rd gens, LG4 (VIN code "H") and L69 used the same head castings, 416 from 1982-1986, and 081 for 1987 LG4's and '87-up LB9's (VIN code "F"). The '85 & '86 LB9 also used the 416 casting. The chamber size (at least as far as the factory is concerned) is determined by the casting. Therefore, LG4, L69 and LB9 will all have the same size chambers.

The '82-'84 3rd gen LG4's had lower compression because they had dished pistons in them, which, when combined with the 58cc chamber 416 heads, produced 8.5:1 compression ratio. The L69's and '85-'86 LG4's & LB9's had flat top pistons with 4 valve reliefs that, when combined with the 58cc chamber 416 heads, produced 9.5:1 compression ratio. '87-up used a slight dish piston with 4 valve reliefs that reduced compression to 9.3:1. The factory typically used steel shim head gaskets, although they have also used composition in later years. And, for the record, 3rd gen LG4's, L69's, and LB9's all used 1.84" intake and 1.50" exhaust valves.

The L69 had a better cam, larger exhaust manifolds and exhaust all the way back, different PROM tuning, knock sensor ('85-up all 305's have knock sensor), different carb calibration, dual snorkel air cleaner for Camaro, cowl induction for Firebird, and electric radiator fan ('86-up all 305's have electric radiator fan).

If you want to improve the performance of an LG4, you do the following: Replace all of the exhaust with headers, y-pipe with 2-1/2" downpipes to 3" at the cat, 3" cat, and 3" cat back to 3" inlet muffler (single 3" outlet or 2 x 2-1/2" outlets is your choice). Replace the cam with something with a little duration and lift (the Crane 2050 worked well in mine). Replace the valve springs with something that can handle the lift of the cam. Upgrade the ignition coil and module with aftermarket pieces. Replace the single-snorkel air cleaner with a dual snorkel unit, either a factory type (Camaros), or fabricated one (see the tech articles on the Board home page, or Link to Home Made Dual Snorkel Post for the latter). If you want, further improvements can be obtained by having the heads reworked for 1.94" intake valves, and cleaning up the port bowl area (do a search for porting, you'll find out what is required). Pinning the rocker studs or having the heads machined for screw-in studs is a very good idea with an upgraded cam & springs. If you want, you can put an aftermarket performance intake on it such as the Weiand Action+ or GMPP q-jet intake manifold. Most of this will also help an L69 or LB9.

If you have an LO3 TBI or LU5 cross-fire - well, those are special cases and you're on your own...



jk, check out the TBI forum "Important/Useful" stickies.
__________________
See detail on my cars in My vBGarage

I'm a racing fool. Not necessarily in that order.

Last edited by five7kid; 12-13-2005 at 06:19 PM.
five7kid is offline vBGarage Page   Reply With Quote
Old 09-28-2004, 07:05 PM   #2
Supreme Member
 
Join Date: Jul 2003
Location: Pensacola, FL
Posts: 1,102
Car: 1999 Saturn SL2
Engine: 4 cylinder
Transmission: 4-speed automatic

Classifieds Rating: (0)
Send a message via AIM to Nate86
LOL @ "If you have an LO3 TBI or LU5 cross-fire - well, those are special cases and you're on your own... "

Thanks for taking the time to write this up. Hopefully this will reduce the amount of "How do I make my LG4 faster?" threads. I will certainly be using it as a reference to any of the said questions.

Just thought I'd make it even easier for everyone by adding a few links to the stuff you mentioned. Enjoy.

Tech Articles
-----------------------------------

Performance CC Quadrajet tuning - http://www.thirdgen.org/newdesign/tech/quadrajet.shtml
Quadrajet secondary metering rods reference - http://www.thirdgen.org/newdesign/tech/rods.shtml
Dual snorkel air cleaner fabrication guide - http://www.thirdgen.org/newdesign/te...lsnorkel.shtml


Important/Useful Threads
-----------------------------------

Head Porting & Polishing - http://www.thirdgen.org/techbb2/show...hreadid=117410
Exhaust FAQ - http://www.thirdgen.org/techbb2/show...hreadid=152269
Header information - http://www.thirdgen.org/techbb2/show...hreadid=204967
A.I.R. information - http://www.thirdgen.org/techbb2/show...hreadid=213310
LG4 Cam recommendations:
http://thirdgen.org/techbb2/showthre...hlight=LG4+Cam
http://thirdgen.org/techbb2/showthre...hlight=LG4+Cam
http://thirdgen.org/techbb2/showthre...hlight=LG4+Cam

Other Stuff
-----------------------------------

In-depth LG4 performance writeup (by five7kid) - http://thirdgen.org/techbb2/showthre...hreadid=227857
Some backpressure information (yes, it is a bad thing) - http://thirdgen.org/techbb2/showthre...t=backpressure
Technical data and power ratings for thirdgen f-bodies - http://www.thirdgen.org/newdesign/tech/techdb.shtml
Vacuum diagram for most LG4/L69 engines - http://thirdgen.org/techbb2/showthre...hreadid=257699
V-belt to serpentine conversion:
1. http://thirdgen.org/techbb2/showthre...ight=vbelt+fan
2. http://sethirdgen.org/serpentine.htm
Mechanical to electric fan writeup (very technical) - http://thirdgen.org/techbb2/showthre...hreadid=248873
Tuneup information (written on the V6 board but applies to almost every thirdgen engine) - http://www.thirdgen.org/techbb2/show...hreadid=162251

Hope that helps!
__________________

| My Car | NWFL ThirdGen Forums | FLThirdGen.org |

Last edited by Nate86; 09-28-2004 at 07:08 PM.
Nate86 is offline vBGarage Page   Reply With Quote
Old 09-29-2004, 12:26 AM   #3
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

Thanks for posting all those links!

I could have added a few other things, like:

All US-delivered carb'd V8 3rd gens were computer controlled (along with the distributor).

All US-delivered carb'd V8 3rd gens had an aluminum intake manifold - and they were the same part whether LG4 or L69 (except the '87 LG4, which had the center two mount bolts on each side at a different angle than the rest - '86-earlier were all the same angle).

LG4's originally delivered to Canada typically were not computer controlled (I believe they finally were in the later years - but don't hold me to that) and had a cast iron intake manifold. However, their L69's were computer controlled and had the aluminum intake.
five7kid is offline vBGarage Page   Reply With Quote
Old 06-01-2005, 08:23 PM   #4
Senior Member
 
Mr.Wolf's Avatar
 
Join Date: May 2005
Location: Pasadena
Posts: 365
Car: 87 Z28
Engine: uh does the name give u a hint
Transmission: 700r4
Axle/Gears: 2.73

Classifieds Rating: (1)
Send a message via Yahoo to Mr.Wolf
i hv carbed 305 whats the cam measurements u suggest?
Mr.Wolf is offline vBGarage Page   Reply With Quote
Old 08-02-2005, 12:51 PM   #5
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

If you retain the computer controls, you should consider a computer-compatible cam. Comp, Crane, Lunati, all carry cams that meet that description. The Crane 2050 cam I referenced is such a cam. It requires a good exhaust and higher stall torque converter (if auto tranny).
five7kid is offline vBGarage Page   Reply With Quote
Old 08-09-2005, 08:27 PM   #6
Senior Member
 
Lucid's Avatar
 
Join Date: Mar 2004
Location: San Antonio, Tx
Posts: 736
Car: 86 Camaro Z28/ 87 Camaro IROC Z28
Engine: 5.0L TPI LB9 / 5.0 TPI LB9 w/cam
Transmission: Built 700R4 with Transgo shift kit
Axle/Gears: 3.27 9 bolt Posi/ 2.73 10 bolt Posi

Classifieds Rating: (4)

Send a message via Yahoo to Lucid
Did the LB9 camaros have different exhaust manifolds than the L69 camaros?
I had heard once that the L69 camaros had better exhaust manifolds and i ran across one at the junk yard, i should have pulled them off but i ran out of time ! (my dad has the LG4 car and i have an LB9).
__________________
~Lucid is a state of mind~
Boxed Panhard Rod and LCA's
KYB Struts and Shocks
3" Catalytic Convertor/Borla Exhaust
140 Amp CS144 Alternator
Ramchargers Dual Fans 2500CFM
http://SA3GO.proboards.com
Lucid is offline vBGarage Page   Reply With Quote
Old 08-18-2005, 01:33 PM   #7
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

LB9 and L69 are different, but fairly equal performance-wise.

The L69 has the EFE valve while the LB9 does not. The L69 EFE valve is bigger than the LG4 valve, so you can't put the L69 manifolds on with the LG4 valve.
five7kid is offline vBGarage Page   Reply With Quote
Old 08-31-2005, 02:44 AM   #8
Senior Member
 
Join Date: Jul 2005
Location: Manchester: UK
Posts: 477
Car: Was 3rd Gen now MustangGT
Engine: 302
Transmission: Auto
Axle/Gears: 3:73:1

Classifieds Rating: (0)
Pardon my ignorance but where should the G be in the Vin code?
ie: mine starts 1G2AW so does that make it an HO?
The reason i ask is it had an HO transfer on the back of the car which was obviously aftermarket.
R1UK is offline vBGarage Page   Reply With Quote
Old 08-31-2005, 07:45 AM   #9
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

8th character of the VIN.
five7kid is offline vBGarage Page   Reply With Quote
Old 08-31-2005, 08:47 AM   #10
Senior Member
 
Join Date: Jul 2005
Location: Manchester: UK
Posts: 477
Car: Was 3rd Gen now MustangGT
Engine: 302
Transmission: Auto
Axle/Gears: 3:73:1

Classifieds Rating: (0)
Thanks again, mines an LG4 then and seems people buy and fit any old stickers.



Now where did i put those 600ci Supercharged stickers............
R1UK is offline vBGarage Page   Reply With Quote
Old 05-08-2006, 05:45 PM   #11
aku
Junior Member
 
Join Date: May 2006
Posts: 8

Classifieds Rating: (0)
are there any aftermarked snorkel kits sold? or just factory/custom ones?
aku is offline vBGarage Page   Reply With Quote
Old 05-08-2006, 09:35 PM   #12
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

Ramair. Goggle it.

Last edited by five7kid; 05-08-2006 at 10:28 PM.
five7kid is offline vBGarage Page   Reply With Quote
Old 05-09-2006, 07:21 PM   #13
Member
 
Join Date: Apr 2006
Location: Center Valley, PA
Posts: 112
Car: 85 Camaro IROC, 88 K-1500
Engine: 357 TPI, 350TBI
Transmission: T-5, NV3500
Axle/Gears: 3.42 posi, 3.73 i believe

Classifieds Rating: (0)
carbs diffrent?

am i correct in thinking that L69s had 650 Q-jets. if so what did the LG4s have? i always thought the carbs were diffrent.
Engine Specs

i'm basing my info on this site, seems to be a very reliable site with good information.
Project84TA is offline vBGarage Page   Reply With Quote
Old 05-09-2006, 07:30 PM   #14
Member
 
Join Date: Apr 2006
Location: Center Valley, PA
Posts: 112
Car: 85 Camaro IROC, 88 K-1500
Engine: 357 TPI, 350TBI
Transmission: T-5, NV3500
Axle/Gears: 3.42 posi, 3.73 i believe

Classifieds Rating: (0)
sorry about the long obnoxious post, i dont know what happend there, just coppied the link and pasted it in my post. it wasn't that big when i copied it
Project84TA is offline vBGarage Page   Reply With Quote
Old 05-09-2006, 08:24 PM   #15
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

The carbs are basically the same but tuned differently. The LG4 had a cast-in "tab" that kept the AV from opening fully (on some LG4's, not all - mine wasn't). The primary jets and secondary rods/hanger were typically different L69 to LG4.

Both carbs have the same capability, basically.

(BTW, don't try to copy a page into a post. Go ahead and copy the URL and put it in your post. Not-so-good things happen when you try to copy content into a post.)
five7kid is offline vBGarage Page   Reply With Quote
Old 05-12-2006, 07:30 AM   #16
Member
 
Join Date: Apr 2006
Location: Center Valley, PA
Posts: 112
Car: 85 Camaro IROC, 88 K-1500
Engine: 357 TPI, 350TBI
Transmission: T-5, NV3500
Axle/Gears: 3.42 posi, 3.73 i believe

Classifieds Rating: (0)
ok, that makes sence, so basically what you find in the "tuning Q-jets" tech article is the only diffrence from the Lg4 carb to the L69. and you're saying that some LG4s have 650s??
Project84TA is offline vBGarage Page   Reply With Quote
Old 05-12-2006, 08:01 AM   #17
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

They flow, or have the capability of flowing, in the 750 to 800 CFM range.
five7kid is offline vBGarage Page   Reply With Quote
Old 08-20-2006, 11:39 PM   #18
Junior Member
 
Join Date: Aug 2006
Location: NEPA
Posts: 22

Classifieds Rating: (0)
mines a 88 h.o? we talkin bout High Output?
5 Spd Formula is offline vBGarage Page   Reply With Quote
Old 08-21-2006, 06:59 AM   #19
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

Officially, "H.O." designations were only from 1983 to 1986 model years, and were only on cars with the L69 carb'd engines VIN code G. If you have an '88, it isn't "H.O.". Some people refer to the LB9 as the "H.O." engine, but technically, it isn't.
five7kid is offline vBGarage Page   Reply With Quote
Old 08-21-2006, 01:02 PM   #20
Junior Member
 
Join Date: Aug 2006
Location: NEPA
Posts: 22

Classifieds Rating: (0)
ooo thats weird my hood says5.0 h.o and those are the orig stickers.. i will look at my build sheet i bought it off my dads cousin who bought it new in 88 its only got 55 thousand on it

but im assuming ur right maybes its just one of those weird things
5 Spd Formula is offline vBGarage Page   Reply With Quote
Old 08-21-2006, 06:47 PM   #21
Junior Member
 
Join Date: Aug 2006
Location: NEPA
Posts: 22

Classifieds Rating: (0)
yeppp sure enough MY BADDD was thinkin of somehting else
5 Spd Formula is offline vBGarage Page   Reply With Quote
Old 09-02-2006, 03:55 PM   #22
Member
 
Z28er's Avatar
 
Join Date: Apr 2006
Location: Cape Breton N.S
Posts: 133
Car: 84 Z28
Engine: 305HO
Transmission: Borg Warner T5
Axle/Gears: 3:73

Classifieds Rating: (0)
Send a message via MSN to Z28er
Quote:
Originally Posted by five7kid View Post
There was only one engine called "HO" in 3rd gens - the L69 (VIN code "G") from '83-'86. There seems to be a lot of confusion over what made it "HO", so here are some basics.

At least in 3rd gens, LG4 (VIN code "H") and L69 used the same head castings, 416 from 1982-1986, and 081 for 1987 LG4's and '87-up LB9's (VIN code "F"). The '85 & '86 LB9 also used the 416 casting. The chamber size (at least as far as the factory is concerned) is determined by the casting. Therefore, LG4, L69 and LB9 will all have the same size chambers.

The '82-'84 3rd gen LG4's had lower compression because they had dished pistons in them, which, when combined with the 58cc chamber 416 heads, produced 8.5:1 compression ratio. The L69's and '85-'86 LG4's & LB9's had flat top pistons with 4 valve reliefs that, when combined with the 58cc chamber 416 heads, produced 9.5:1 compression ratio. '87-up used a slight dish piston with 4 valve reliefs that reduced compression to 9.3:1. The factory typically used steel shim head gaskets, although they have also used composition in later years. And, for the record, 3rd gen LG4's, L69's, and LB9's all used 1.84" intake and 1.50" exhaust valves.

The L69 had a better cam, larger exhaust manifolds and exhaust all the way back, different PROM tuning, knock sensor ('85-up all 305's have knock sensor), different carb calibration, dual snorkel air cleaner for Camaro, cowl induction for Firebird, and electric radiator fan ('86-up all 305's have electric radiator fan).

If you want to improve the performance of an LG4, you do the following: Replace all of the exhaust with headers, y-pipe with 2-1/2" downpipes to 3" at the cat, 3" cat, and 3" cat back to 3" inlet muffler (single 3" outlet or 2 x 2-1/2" outlets is your choice). Replace the cam with something with a little duration and lift (the Crane 2050 worked well in mine). Replace the valve springs with something that can handle the lift of the cam. Upgrade the ignition coil and module with aftermarket pieces. Replace the single-snorkel air cleaner with a dual snorkel unit, either a factory type (Camaros), or fabricated one (see the tech articles on the Board home page, or Link to Home Made Dual Snorkel Post for the latter). If you want, further improvements can be obtained by having the heads reworked for 1.94" intake valves, and cleaning up the port bowl area (do a search for porting, you'll find out what is required). Pinning the rocker studs or having the heads machined for screw-in studs is a very good idea with an upgraded cam & springs. If you want, you can put an aftermarket performance intake on it such as the Weiand Action+ or GMPP q-jet intake manifold. Most of this will also help an L69 or LB9.

If you have an LO3 TBI or LU5 cross-fire - well, those are special cases and you're on your own...



jk, check out the TBI forum "Important/Useful" stickies.

so what your saying is: do these mods to your car and it will just be as good as a L69?

Last edited by Z28er; 09-02-2006 at 03:57 PM. Reason: wrong engine code
Z28er is offline vBGarage Page   Reply With Quote
Old 09-03-2006, 02:03 AM   #23
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

That's right.

The L69 cars did have the AC line routed slightly differently to stay out of the way of the passenger side snorkel, but I haven't had any problems with the LG4 line & L69 snorkel.
five7kid is offline vBGarage Page   Reply With Quote
Old 12-12-2006, 10:17 PM   #24
Junior Member
 
Join Date: Feb 2004
Posts: 49

Classifieds Rating: (0)
Send a message via AIM to freestylin
the 8th letter in my vin is a E what kind of engine is this does anyone know
freestylin is offline vBGarage Page   Reply With Quote
Old 12-12-2006, 10:20 PM   #25
Senior Member
 
Join Date: Jul 2002
Location: Burnaby, BC
Posts: 823
Car: Custom 1992 Camaro Z28 25th Anniversary Ed.
Engine: 5.7L V8 350 L98 TPI

Classifieds Rating: (1)

Send a message via ICQ to camarosource
Quote:
Originally Posted by freestylin View Post
the 8th letter in my vin is a E what kind of engine is this does anyone know
Enter your VIN : http://www.camarosource.ca/php/camar...year=2002&tm=1
__________________
1992 Camaro Z28. Blue/silver, Custom Blue/Silver Leather seats, Rebuilt Engine, Cammed, Headers, TT ][ Rims ...
NEW WWW.CAMAROSOURCE.CA

Camarosource.ca FACEBOOK PAGE - EXCLUSIVE INFO On upcoming Camarosource.ca V5.0 and More!!


camarosource is offline vBGarage Page   Reply With Quote
Old 12-12-2006, 10:42 PM   #26
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

(Edit: try this again)E = LO3 305 TBI.

Last edited by five7kid; 12-13-2006 at 07:06 AM.
five7kid is offline vBGarage Page   Reply With Quote
Old 12-12-2006, 11:49 PM   #27
Junior Member
 
Join Date: Feb 2004
Posts: 49

Classifieds Rating: (0)
Send a message via AIM to freestylin
i entered in the vin online and it says its a v8 305 tbi i just wanted to know ifit was ho or lb9 or what it is its a firebird btw
freestylin is offline vBGarage Page   Reply With Quote
Old 12-13-2006, 12:11 AM   #28
Junior Member
 
Join Date: Feb 2004
Posts: 49

Classifieds Rating: (0)
Send a message via AIM to freestylin
okay i got it its a LO3 anyone got any info on these engines
freestylin is offline vBGarage Page   Reply With Quote
Old 12-13-2006, 07:10 AM   #29
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

http://www.thirdgen.org/1988-pontiac-firebird

LO3 = 170 horse base V8. Lo-po, designed for some semblance of power while maintaining good standing with the government's CAFE (corporate average fuel economy) requirements, "at least I can say it's a V8".
five7kid is offline vBGarage Page   Reply With Quote
Old 12-21-2006, 07:16 AM   #30
Supreme Member
 
coolram62's Avatar
 
Join Date: Dec 2005
Location: Beaufort South Carolina
Posts: 1,738
Car: 1983 Camaro Z/28
Engine: LU5 305 CFI
Transmission: 700R4
Axle/Gears: J65/G80/G92-3.23

Classifieds Rating: (2)
Just to add,for those of us on our own...LOL,the LU5 CFI motors used the same 9.5 compression as the L69.And the stock cam specs fit in between those of the LG4 (.234/.257),LU5 (.257/.269) and the L69 (.269/.276).The LU5 (250 ft/lb@2800 RPM)produced similar torque at a lower RPM than the L69 (249 ft/lb@3200 RPM).The L69 (190 HP@4800 RPM) had the horsepower edge over the LU5 (175@4200 RPM) but again at a higher RPM.
The L69's big advantage was the exhaust system.That along with the electric fan,available 5 speed and deeper rear gears (3.73 vs 3.23 LU5 w/G92) all added up.And yes the CFI can be tempramental.But it can be made to perform.
__________________
'07 Avalanche LTZ 5.3 FFV/4L60E/3.73,K&N CAI,Magnaflow,Superchips Flaspaq
'83 Z/28 LU5 305 CFI/K&N/Factory Dual Electric Fans/MSD-Hypertech Coil/Performance Rebuilt 700R4/JG1/J65/G80/G92-3.23/Hollow 36mm front-24mm rear bar,TDS steering brace,16" single stripe IROC /T-tops/Pwr everything
'73 C-10 CST 454/TH400(Factory BB Truck)A/C,Tilt,12 Bolt Posi,Dynomax
Miss my '70 Monte Carlo SS454
coolram62 is offline vBGarage Page   Reply With Quote
Old 01-29-2007, 01:19 PM   #31
Junior Member
 
classiciron's Avatar
 
Join Date: Jan 2007
Location: Ohio
Posts: 4
Car: 1982 Z-28 Camaro
Engine: 305
Transmission: Automatic
Axle/Gears: Positraction

Classifieds Rating: (0)
Hi,are you sure 82 didn't have a HO engine option? I have an 82 Z28 that has HO in the VIN numbers. Which I assumed met it was a high output motor.
Dennis
__________________

Dennis' '82 Z-28 Camaro
classiciron is offline vBGarage Page   Reply With Quote
Old 01-29-2007, 02:12 PM   #32
Senior Member
 
Join Date: Jul 2002
Location: Burnaby, BC
Posts: 823
Car: Custom 1992 Camaro Z28 25th Anniversary Ed.
Engine: 5.7L V8 350 L98 TPI

Classifieds Rating: (1)

Send a message via ICQ to camarosource
Quote:
Originally Posted by classiciron View Post
Hi,are you sure 82 didn't have a HO engine option? I have an 82 Z28 that has HO in the VIN numbers. Which I assumed met it was a high output motor.
Dennis
What is your VIN #?
camarosource is offline vBGarage Page   Reply With Quote
Old 01-29-2007, 03:33 PM   #33
Junior Member
 
classiciron's Avatar
 
Join Date: Jan 2007
Location: Ohio
Posts: 4
Car: 1982 Z-28 Camaro
Engine: 305
Transmission: Automatic
Axle/Gears: Positraction

Classifieds Rating: (0)
1G1AP87HOCN107527

Here is my VIN number
classiciron is offline vBGarage Page   Reply With Quote
Old 01-29-2007, 03:53 PM   #34
Junior Member
 
classiciron's Avatar
 
Join Date: Jan 2007
Location: Ohio
Posts: 4
Car: 1982 Z-28 Camaro
Engine: 305
Transmission: Automatic
Axle/Gears: Positraction

Classifieds Rating: (0)
I guess it has the LG4 Engine, my mistake.
classiciron is offline vBGarage Page   Reply With Quote
Old 02-03-2007, 09:34 AM   #35
Junior Member
 
Join Date: Dec 2006
Location: Carrollton IL
Posts: 59
Car: 89 Camaro RS
Engine: LO3
Transmission: 700r4
Axle/Gears: 273 pegleg

Classifieds Rating: (2)
Brand new to the ThirdGen board, having just bought my first Camaro. As luck would have it, I got a 89 RS with the LO3 engine, twenty more horsepower than my old Neon. What are the major differences between the LO3 and the LG4 engines, which appear to be rated the same horsepower wise, other than the induction. Would I be better off in the long run changing engines??

Dave Berry
D BERRY is offline vBGarage Page   Reply With Quote
Old 02-03-2007, 04:33 PM   #36
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

The LO3 used a roller lifter cam, electronic throttle body injection, and "swirl port" heads. Great for fuel economy, pretty much maxed out the way the factory made it. The "best" LG4 had 165 HP, 145-155 much more common. So, the LO3 and its 170 HP was a little better, and emissions and fuel economy were improved over the LG4.

If trying to improve an LO3, add "replace heads" to the above list. Then, do what was said in the original post, check out the TBI forum.
five7kid is offline vBGarage Page   Reply With Quote
Old 02-04-2007, 01:17 PM   #37
Junior Member
 
Join Date: Dec 2006
Location: Carrollton IL
Posts: 59
Car: 89 Camaro RS
Engine: LO3
Transmission: 700r4
Axle/Gears: 273 pegleg

Classifieds Rating: (2)
Thanks, I'll check out the TBI forum!
D BERRY is offline vBGarage Page   Reply With Quote
Old 03-29-2007, 10:57 PM   #38
Senior Member
 
Join Date: Mar 2007
Location: Jackson, Michigan
Posts: 343
Car: 83 Trans Am
Engine: LT1 350
Transmission: 5 Speed manual
Axle/Gears: 3.73 10bolt till it breaks

Classifieds Rating: (0)
Re: Differences between 305 engines, performance tips

I am getting an 83 T/A with LG4 so I'd just like to say thank you to all involved with this thread for the great information. its weird though cause my T/A also has the HO decals. I dont know why someone would put an HO decal on a fake HO car? Kinda stupic in my opinion. Thats something I expect from ricers. Now if the engines and all are switched to the HO equipment then I could understand it. lets just hope mine has been converted properly, or else teh decals will be removed.

Last edited by hgffrank; 03-29-2007 at 11:04 PM.
hgffrank is offline vBGarage Page   Reply With Quote
Old 12-06-2007, 10:52 PM   #39
Supreme Member
 
Ozz1967's Avatar
 
Join Date: Dec 2005
Location: Layton, UT
Posts: 3,259
Car: 1984 Trans Am
Engine: 355
Transmission: 700R4
Axle/Gears: Zexel Torsen 3.73

Classifieds Rating: (4)
Re: Differences between 305 engines, performance tips

Quote:
Originally Posted by camarosource View Post
I attempted to decode my vin # on this web site but it comes back as "Not a valid 17 digit vin number"...

Carfax finds it, but two other web sites that I went to couldn't.

Any ideas?

---EDIT---

Found it here

http://www.fbodydomain.com/VIN/VIN.asp#1982

Mine is definitely an 84 Trans Am, L69 car. What threw me was the 4th digit was an "A", not "F" for Fbody like some say. Apparantly the "A" stands for manual restraint system.
__________________
Pontiac Owners Club (UK)
Thirdgen.org on Facebook
My 84 Trans Am <-- Oh, click me! Click me!
My 67 Camaro <-- Or me! Or me!
"Life is tough. It's tougher when you're stupid!" (John Wayne)
Freedom Is Never Free!

Last edited by Ozz1967; 12-06-2007 at 11:13 PM. Reason: Found a page that helped
Ozz1967 is offline vBGarage Page   Reply With Quote
Old 04-28-2008, 10:22 PM   #40
Member
 
69-er's Avatar
 
Join Date: Oct 1999
Location: Alamogordo, NM, USA
Posts: 192
Car: 1969 Z/28, 1983 Z/28, 2010 SS
Engine: 302, 305 (L69), LS-3
Transmission: M21, T5, T6060

Classifieds Rating: (0)

Re: Differences between 305 engines, performance tips

Quote:
Originally Posted by five7kid View Post
8th character of the VIN.
Just for the record, in 83, the 8th character for an L69 was a "7". I think I read somewhere that it changed to a "G" in 84. My 83 L69 has a "7".

Larry

Last edited by 69-er; 04-28-2008 at 10:23 PM. Reason: Changed to "Instant Email Notification"
69-er is offline vBGarage Page   Reply With Quote
Old 11-18-2008, 05:22 PM   #41
Member
 
Join Date: Sep 2003
Posts: 143
Car: -88 TA GTA
Engine: 350 tpi
Transmission: TH700

Classifieds Rating: (0)

Re: Differences between 305 engines, performance tips

Quote:
Originally Posted by five7kid View Post
The carbs are basically the same but tuned differently. The LG4 had a cast-in "tab" that kept the AV from opening fully (on some LG4's, not all - mine wasn't). The primary jets and secondary rods/hanger were typically different L69 to LG4.

Both carbs have the same capability, basically.

(BTW, don't try to copy a page into a post. Go ahead and copy the URL and put it in your post. Not-so-good things happen when you try to copy content into a post.)
So, what rods/hanger did the L69 use? I think Ill use them when modifying my lg4 carb, since Ive done a lot of other mods..And Im retaining the ccc so I need something compatible
HasseO is offline vBGarage Page   Reply With Quote
Old 11-18-2008, 05:34 PM   #42
Senior Member
 
Lucid's Avatar
 
Join Date: Mar 2004
Location: San Antonio, Tx
Posts: 736
Car: 86 Camaro Z28/ 87 Camaro IROC Z28
Engine: 5.0L TPI LB9 / 5.0 TPI LB9 w/cam
Transmission: Built 700R4 with Transgo shift kit
Axle/Gears: 3.27 9 bolt Posi/ 2.73 10 bolt Posi

Classifieds Rating: (4)

Send a message via Yahoo to Lucid
Re: Differences between 305 engines, performance tips

You would also want to get an L69 ECM or just the L69 chip. If you can find a verified source for a monte carlo SS like an 88 model year, it has a better ECM and will work mighty fine. The difference is the spark advance programmed in the chip.
Lucid is offline vBGarage Page   Reply With Quote
Old 08-15-2011, 07:43 PM   #43
Junior Member
 
Join Date: Aug 2011
Location: Falls City Nebraska
Posts: 7
Car: 1985 Camaro Iroc-Z
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)
Re: Differences between 305 engines, performance tips

my vin is 1g1fp87f6f1489339
Kelby Jones is offline vBGarage Page   Reply With Quote
Old 08-15-2011, 07:45 PM   #44
Junior Member
 
Join Date: Aug 2011
Location: Falls City Nebraska
Posts: 7
Car: 1985 Camaro Iroc-Z
Engine: 305 TPI
Transmission: 700R4

Classifieds Rating: (0)
Re: Differences between 305 engines, performance tips

im wondering what it is
Kelby Jones is offline vBGarage Page   Reply With Quote
Old 08-15-2011, 10:58 PM   #45
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

Originally it was an LB9, TPI 305.

Anybody's guess what it is now.
five7kid is offline vBGarage Page   Reply With Quote
Old 08-16-2011, 06:43 AM   #46
Senior Member
 
Join Date: May 2011
Location: in a huge granite cave
Posts: 1,198
Car: '84 & '86 Camaros
Engine: building turbo 5.3L, & 3.4L
Transmission: 4L80E & 700R-4
Axle/Gears: TBD & 3.42:1

Classifieds Rating: (0)
Re: Differences between 305 engines, performance tips

Quote:
Originally Posted by coolram62 View Post
Just to add,for those of us on our own...LOL,the LU5 CFI motors used the same 9.5 compression as the L69.And the stock cam specs fit in between those of the LG4 (.234/.257),LU5 (.257/.269) and the L69 (.269/.276).The LU5 (250 ft/lb@2800 RPM)produced similar torque at a lower RPM than the L69 (249 ft/lb@3200 RPM).The L69 (190 HP@4800 RPM) had the horsepower edge over the LU5 (175@4200 RPM) but again at a higher RPM.
The L69's big advantage was the exhaust system.That along with the electric fan,available 5 speed and deeper rear gears (3.73 vs 3.23 LU5 w/G92) all added up.And yes the CFI can be tempramental.But it can be made to perform.
I see some errors here. The '82 LU5 was 8.6:1, the '83 was 9.5:1.
The LG4 cam was 178/194, .233/.257", the LU5 cam was 195/202, .260/.273", 112@108, and the L69/LB9 cam was 201/206, .269/.276, 114.5@115
ronnjonn is offline vBGarage Page   Reply With Quote
Old 08-16-2011, 08:17 AM   #47
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

This is our source:
http://www.thirdgen.org/1982-chevy-camaro

What's yours?
five7kid is offline vBGarage Page   Reply With Quote
Old 08-16-2011, 09:28 AM   #48
Senior Member
 
screaminformula's Avatar
 
Join Date: May 2002
Location: Montgomery, AL...for now
Posts: 772
Car: 1987 F150...PAAARTY FOUL!
Engine: 300 I6 stump pullin sumbiscuit
Transmission: 4 speed grind box
Axle/Gears: 3.55 unlimited slip differential

Classifieds Rating: (0)
Send a message via AIM to screaminformula Send a message via Yahoo to screaminformula
Re: Differences between 305 engines, performance tips

great, informative post...but i'm gonna disagree about one thing. the L69 was NOT the only "official" H.O. engine. my buddy's 86 Trans Am that is all stock with the LB9 TPI 305 has stickers on the sides that say "5.0 Liter H.O.". and, in my thinking, if GM put "H.O." on the car...then it was about as official as you can get.
screaminformula is offline vBGarage Page   Reply With Quote
Old 08-16-2011, 09:08 PM   #49
Senior Member
 
Join Date: May 2011
Location: in a huge granite cave
Posts: 1,198
Car: '84 & '86 Camaros
Engine: building turbo 5.3L, & 3.4L
Transmission: 4L80E & 700R-4
Axle/Gears: TBD & 3.42:1

Classifieds Rating: (0)
Re: Differences between 305 engines, performance tips

Quote:
Originally Posted by five7kid View Post
This is our source:
http://www.thirdgen.org/1982-chevy-camaro

What's yours?
Old GM service manuals.
ronnjonn is offline vBGarage Page   Reply With Quote
Old 08-16-2011, 09:39 PM   #50
Moderator
 
five7kid's Avatar
 
Join Date: Mar 2000
Location: Littleton, CO USA
Posts: 42,050
Car: 82 Berlinetta/57 Bel Air
Engine: LS1/LQ4
Transmission: 4L60E/4L80E
Axle/Gears: 10B-3.73/9"-3.89

Classifieds Rating: (14)

Quote:
Originally Posted by screaminformula View Post
great, informative post...but i'm gonna disagree about one thing. the L69 was NOT the only "official" H.O. engine. my buddy's 86 Trans Am that is all stock with the LB9 TPI 305 has stickers on the sides that say "5.0 Liter H.O.". and, in my thinking, if GM put "H.O." on the car...then it was about as official as you can get.
Was he the original owner?
five7kid is offline vBGarage Page   Reply With Quote
Old 08-16-2011, 09:39 PM
ThirdGen
1992 Camaro




Paid Advertisement


Reply

Go Back   Third Generation F-Body Message Boards > Tech Boards > FAQ Board

Tags
1985, 305, 43, diagram, intake, l69, lg4, manifold, metering, performance, primary, quadrajet, rod, size, specs
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 


1982 Camaro '82 || 1983 Camaro '83 || 1984 Camaro '84 || 1985 Camaro '85 || 1986 Camaro '86 || 1987 Camaro '87 || 1988 Camaro '88 || 1989 Camaro '89 || 1990 Camaro '90 || 1991 Camaro '91 || 1992 Camaro '92


All times are GMT -5. The time now is 08:10 AM.


Powered by vBulletin® Version 3.7.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.5.2
All content copyright 1997 - 2014 ThirdGen.org. All rights reserved. No part of this website may be reproduced without the expressed, documented, and written consent of ThirdGen.org's Administrators.

Emails & Contact Details