delete thanks

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

Ive got an 87 LG4 engine sitting here, and it has flat-tops. Which = 9.5:1

From 1985 to 1987 the LG4 got the same pistons as the L69.

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

Depending on what heads are on it.

true that


wonder about the cams too.. hmm..


wonder if these higher CR LG4 got teh L69 cam too ?


hmmm

thanks

Not a chance. If they did they'd be L69s.

so they made a half @ssed L69(just L69 flat tops) but still called it LG4, etc

lol

thats interesting

hehe

thanks

Not exactly, they just started using the same short block on the LG4 as all the other 305s to cut costs.

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.

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

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.....

It's possible the pistons or block weren't original, I suppose.

Its number matched my VIN... oh well. Wondering about it wont change my memory, however my memory has gotten crappy lately...

John

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

Last week, I was cleaning out my garage, and there was an engine under a tarp. I was told it was a ford block when I bought the place and someone was supposed to pick it up. 2 years, still there, so I decide to strip it so I can pick it up to haul to the dump. I removed the tarp, and WTH? it's a chev.

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.

You can figure out the info. its on the tech data page here on TGO,

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

It doesn't make any difference what it was, the short blocks were the same. What's more important is what it's going to be.

Thats true except for the 82-84 LG4, and the cam.

John

I wanted to try and find out the factory horsepower rating for it.

refer to the Tech data page

John

Factory cams aren't worth keeping, even the L69 cam.