85-87 LG4 with 9.3 and 9.5 CR ?
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From: 62656
Car: 1991 S10 pickup 2700lbs
Engine: 4.3L Z TBI
Transmission: 700R4
Axle/Gears: 3.08 7.625"
85-87 LG4 with 9.3 and 9.5 CR ?
delete
thanks
thanks
Last edited by Randy82WS7; Apr 11, 2006 at 02:33 PM.
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From: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
8.6:1 compression actually for 1987. 9.5 would have made it an H.O. Which incidently does not exist. My 87 was originally a dished piston dog.
There are alot of errors on the page, no one has taken the time to redo it. sounds like my Formula Page, I am getting mine worked out tho. slowly...
John
There are alot of errors on the page, no one has taken the time to redo it. sounds like my Formula Page, I am getting mine worked out tho. slowly...
John
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Joined: Mar 2002
Posts: 4,812
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From: 62656
Car: 1991 S10 pickup 2700lbs
Engine: 4.3L Z TBI
Transmission: 700R4
Axle/Gears: 3.08 7.625"
ill be damned
learn something new every day
so basically any 305 you find with flats in it is probably a 9.3 or better CR 305,.. no matter the RPO ?
or ?
thanks
learn something new every day
so basically any 305 you find with flats in it is probably a 9.3 or better CR 305,.. no matter the RPO ?
or ?
thanks
Thread Starter
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Joined: Mar 2002
Posts: 4,812
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From: 62656
Car: 1991 S10 pickup 2700lbs
Engine: 4.3L Z TBI
Transmission: 700R4
Axle/Gears: 3.08 7.625"
Originally posted by Apeiron
Depending on what heads are on it.
Depending on what heads are on it.
wonder about the cams too.. hmm..
wonder if these higher CR LG4 got teh L69 cam too ?
hmmm
thanks
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Thread Starter
Supreme Member
Joined: Mar 2002
Posts: 4,812
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From: 62656
Car: 1991 S10 pickup 2700lbs
Engine: 4.3L Z TBI
Transmission: 700R4
Axle/Gears: 3.08 7.625"
so they made a half @ssed L69(just L69 flat tops) but still called it LG4, etc
lol
thats interesting
hehe
thanks
lol
thats interesting
hehe
thanks
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Joined: Jan 2000
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Not exactly, they just started using the same short block on the LG4 as all the other 305s to cut costs.
Joined: Dec 2004
Posts: 1,132
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From: Midwest
Car: '82 Recaro T/A, '71 Trans Am
Engine: 305CFI/455HO
Transmission: TH700R4/M22
Axle/Gears: 3.23/3.42
By the end of the LG4's life it gained most of the goodies that were on the L69 5.0L HO engine. By 1987 the lowly LG4 was pumping out 170HP. When it was introduced it was only making about 145HP.
Most of the gain in the LG4 from 145HP to 170HP was from the L69 electric cooling fan, higher compression, and Electronic Spark Control. The big thing holding back the LG4 was the economy minded "peanut cam"
If you took a late model LG4 and installed the L69 cam, higher flowing catylatic converter and exhaust system, and the PROM you'd pretty much have an L69 engine.
Most of the gain in the LG4 from 145HP to 170HP was from the L69 electric cooling fan, higher compression, and Electronic Spark Control. The big thing holding back the LG4 was the economy minded "peanut cam"
If you took a late model LG4 and installed the L69 cam, higher flowing catylatic converter and exhaust system, and the PROM you'd pretty much have an L69 engine.
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From: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
I thought for sure my 87 Formula engine had dished pistons when I took it apart.
But looking at the parts & illustration catalog, apparently not.
according ot the Parts & illustration Catalogs for FIREBIRD:
Pistons:
82-84 LG4 364702
82-83 LU5 14081291
83-86 L69 14081291
85-86 LG4 14081291
85-86 LB9 14081291
82-83 LB9 L69 & 14081291
87 LG4 14094013
87-92 LB9 14094013
88-92 LO3 14094013
Heads:
82-86 LG4, LU5, L69, LB9 14034807
87 LG4 10159553
87-92 LB9 10159553
88-92 LO3 10159551
Cam:
82-83 LU5 14088839
82-86 LG4 14088841
83-86 L69 14088843
85 LB9 14088843
86 LB9 14094097
87 LG4 14093630
87 LB9/A4 14093630
87 LB9/M5 14093643
88-89 LB9/A4 10088155
88-89 LB9/M5 10066049
88-92 LO3 10088155
90-92 LB9 10111773
John
But looking at the parts & illustration catalog, apparently not.according ot the Parts & illustration Catalogs for FIREBIRD:
Pistons:
82-84 LG4 364702
82-83 LU5 14081291
83-86 L69 14081291
85-86 LG4 14081291
85-86 LB9 14081291
82-83 LB9 L69 & 14081291
87 LG4 14094013
87-92 LB9 14094013
88-92 LO3 14094013
Heads:
82-86 LG4, LU5, L69, LB9 14034807
87 LG4 10159553
87-92 LB9 10159553
88-92 LO3 10159551
Cam:
82-83 LU5 14088839
82-86 LG4 14088841
83-86 L69 14088843
85 LB9 14088843
86 LB9 14094097
87 LG4 14093630
87 LB9/A4 14093630
87 LB9/M5 14093643
88-89 LB9/A4 10088155
88-89 LB9/M5 10066049
88-92 LO3 10088155
90-92 LB9 10111773
John
Thread Starter
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Joined: Mar 2002
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From: 62656
Car: 1991 S10 pickup 2700lbs
Engine: 4.3L Z TBI
Transmission: 700R4
Axle/Gears: 3.08 7.625"
nice info ! 
too bad we cant find specs on each cam like lobe info and such
and block castings or stampings
the ho305 out of this 84 i am getting i am gonna stash away since its the original numbers matching block, i have the heads too, but all has been sitting out in weather rusted
can be fixed but not in current times
it was a running engine but the stupid kid left hood off and was gonna replace head gaskets and well he stopped after yanking heads and let it sit no hood for several months so it froze the engine up
the original ho 305.....

too bad we cant find specs on each cam like lobe info and such
and block castings or stampings
the ho305 out of this 84 i am getting i am gonna stash away since its the original numbers matching block, i have the heads too, but all has been sitting out in weather rusted
can be fixed but not in current times
it was a running engine but the stupid kid left hood off and was gonna replace head gaskets and well he stopped after yanking heads and let it sit no hood for several months so it froze the engine up
the original ho 305.....
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Originally posted by okfoz
I thought for sure my 87 Formula engine had dished pistons when I took it apart.
I thought for sure my 87 Formula engine had dished pistons when I took it apart.
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Joined: Mar 2001
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From: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
Its number matched my VIN... oh well. Wondering about it wont change my memory, however my memory has gotten crappy lately...
John
John
Thread Starter
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Joined: Mar 2002
Posts: 4,812
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From: 62656
Car: 1991 S10 pickup 2700lbs
Engine: 4.3L Z TBI
Transmission: 700R4
Axle/Gears: 3.08 7.625"
hey all i need to find a set of 80-up 305 heads, so if anyone knows of a good stock pair for sale then lemme know i prefer 601 or 4416 castings, 58cc
or if you have just one 4416 head then lemme know that cuz i already have one but need to find another.,
i can western union the money and i would want them wrapped in cardboard and tape and sent out post office parcel post rate to 62656
www.usps.com for the post office postage calculator, i pay it all
thanks
or if you have just one 4416 head then lemme know that cuz i already have one but need to find another.,
i can western union the money and i would want them wrapped in cardboard and tape and sent out post office parcel post rate to 62656
www.usps.com for the post office postage calculator, i pay it all
thanks
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Joined: Nov 2004
Posts: 252
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From: Saskatchewan
Car: 84 Z28HO
Engine: 350 summit block
Transmission: T5
Axle/Gears: 3.73 10bolt
Originally posted by Apeiron
From 1985 to 1987 the LG4 got the same pistons as the L69.
From 1985 to 1987 the LG4 got the same pistons as the L69.
Anyway, so I pull it all apart to see what it looks like, looks really nice, no bearing wear, etc.. The block number is 14088551, the crank number is 14088526, and the haeds are 416's - 14014416. I have determined this to be an 86' 305 (from Mortec). It has dished pistons. Does anyone have any idea on what this is, as in LG4, LU5, etc...?
Pics are on page 4 on my cardomain site.
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From: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
Originally posted by Fast68
nice info !
too bad we cant find specs on each cam like lobe info and such
nice info !

too bad we cant find specs on each cam like lobe info and such
1985 (L69 and LB9)
305 AT 14088843 .403 .415 202 206 114.5 (115/-114)
1986 (LB9)
305 AT 14094097 .350 .385 178 194 109.0 (106/-112)
1987
305 AT (LB9 10088155* .350 .384 179 194 109.0 (108/-112)
305 5spd / 350 AT
(LB9/ L98) 14093643* .404 .415 202 207 114.5 (115/-114)
305
(LM1 Police Pack.) 14093640* .383 .404 291 202 112 (108/-116)
1988, 1989
305 AT 10088155* .350 .384 179 194 109.0 (108/-112)
305 5spd / 350 AT 10066049* .415 .430 207 213 117.0 (116/-118)
1990-1992
305 5spd / 305 AT 10088155* .350 .384 179 194 109.0
305 G92 5spd / 350 AT 10111773* .413 .428 202 207 114.5 (116/-116)
* indicates roller cam
You can also decifer the same information at good autoparts stores that do machine work. Many times their books offer the info as a reference.
John
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Originally posted by Zed'er
Does anyone have any idea on what this is, as in LG4, LU5, etc...?
Does anyone have any idea on what this is, as in LG4, LU5, etc...?
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From: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
Thats true except for the 82-84 LG4, and the cam.
John
John
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Joined: Mar 2001
Posts: 14,298
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From: Doghouse ······································ Car: 1989 Formula 350 Vert Engine: 350 L98 Transmission: 700R4 Axle/Gears: B&W 3.27
Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
refer to the Tech data page
John
John
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Joined: Jan 2000
Posts: 20,981
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Originally posted by okfoz
Thats true except for the 82-84 LG4, and the cam.
Thats true except for the 82-84 LG4, and the cam.
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