1987 LG4, Roller or Tappet? Answered!!
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From: Kelowna BC
Car: 87 Z/28
Engine: 5.0L
Transmission: T5
Axle/Gears: 9 Bolt posi
1987 LG4, Roller or Tappet? Answered!!
Well, after a looong time of searching and searching, and most people seeming to think the 87 carb'd motors were in fact roller motors. Kind of odd seeing how GM decided to place the new style heads on the LG4 in '87. But in fact, it is a tappet cam!
And now I know I can't just be saying things on here without proof. soo.. PICS!!
Getting ready to pull!


This is the LG4 from my '87

And the LB9 I picked up just in case. but I'll keep the LG4
And now I know I can't just be saying things on here without proof. soo.. PICS!!
Getting ready to pull!


This is the LG4 from my '87

And the LB9 I picked up just in case. but I'll keep the LG4
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From: Not in Kansas anymore
Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Re: 1987 LG4, Roller or Tappet? Answered!!
Observe though , your block has provision for the roller cam ; just that the bosses for the spider hold down bolts were not machined at the factory.
Probably the same for the roller cam retainer bolts behind the cam gear ?
Probably the same for the roller cam retainer bolts behind the cam gear ?
Re: 1987 LG4, Roller or Tappet? Answered!!
Crafty- those 87s are a box of chocolates. You never know what you're going to get. I had an 87 TBI engine that was also supposed to be roller cam.... it wasn't. Looked just like yours
I think the factory threw together whatever they had laying around the joint that year. No rhyme or reason.
I think the factory threw together whatever they had laying around the joint that year. No rhyme or reason.
Joined: Apr 2005
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From: Not in Kansas anymore
Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Re: 1987 LG4, Roller or Tappet? Answered!!
where required
or as in the case of of a '94 truck TBI engine I have , just put a flat tappet cam in a fully prepped '638 roller block
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From: GO PACK GO
Car: 83Z28 HO
Engine: Magnacharged Dart Little M 408
Transmission: G Force 5 speed
Axle/Gears: Moser 9" w/Detroit Trutrac
Re: 1987 LG4, Roller or Tappet? Answered!!
Doesn't surprise me....they used v belts with serpentine that year. Seems they couldn't decide on anything!!
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From: Murrieta California
Car: 1969 RS Z28 X33 Norwood built
Engine: 383 Stroker
Transmission: T10 4 speed
Re: 1987 LG4, Roller or Tappet? Answered!!
I remember well the 87 that I had back in 1994 had the washer pump on the side of the fluid tank. It was built in late 87. My current 87 has it in the wiper motor housing and it was built in early 87. It seems like they were in the middle of changing a few things that year. Im amazed that they were still using the LG4 by 1987.
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From: RI
Car: 1984 Camaro Berlinetta
Engine: LT1
Transmission: T56 6-speed
Axle/Gears: 4.11 LS1 Rear End
Re: 1987 LG4, Roller or Tappet? Answered!!
+1 The first question that came to my mind.
I always assumed that all 87 engines were roller blocks with Self Aligning rocker arms till I was messing with some 87 TPI heads and learned that they (at least some) used non-SA rockers. However; I've never seen a non-roller 87 block.........
Welllllllllll,....... the 85-87 still used a "V" belt pulley system. The alternator belt simply changed from a true "V" belt to a ribbed belt. That change also changed the design of the WP pulley and crank pulley those years. There was still a seperate belt required for each accessory.
I always assumed that all 87 engines were roller blocks with Self Aligning rocker arms till I was messing with some 87 TPI heads and learned that they (at least some) used non-SA rockers. However; I've never seen a non-roller 87 block.........
Welllllllllll,....... the 85-87 still used a "V" belt pulley system. The alternator belt simply changed from a true "V" belt to a ribbed belt. That change also changed the design of the WP pulley and crank pulley those years. There was still a seperate belt required for each accessory.
Joined: Apr 2005
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From: Not in Kansas anymore
Car: 82 Z28
Engine: 383 SP EFI/ 4150 TB
Transmission: T400
Axle/Gears: QP 9" 3.73
Joined: Aug 1999
Posts: 5,256
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From: RI
Car: 1984 Camaro Berlinetta
Engine: LT1
Transmission: T56 6-speed
Axle/Gears: 4.11 LS1 Rear End
Re: 1987 LG4, Roller or Tappet? Answered!!
Based on the pulleys & upper Alt Bracket,... 87.
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From: Short Summer, VT
Car: 1985 Trans Am T-Top
Engine: 305 TPI
Transmission: T-5 5 Speed
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Re: 1987 LG4, Roller or Tappet? Answered!!
Yes, many belts, but technically not any SERPENTINE belts as the pulleys all run inside the belt, where a serpentine belt runs pulleys on both sides of the belt.
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
'86 & '87 used that set-up.
However, I do know the '86 carb and '87 TPI, at least, used different electrical connectors (for AC, alternator). But, I don't know if '86 carb was the same as '86 TPI, or '87 carb the same as '87 TPI.
Still waiting to hear if the car's VIN # was stamped on the block.
However, I do know the '86 carb and '87 TPI, at least, used different electrical connectors (for AC, alternator). But, I don't know if '86 carb was the same as '86 TPI, or '87 carb the same as '87 TPI.
Still waiting to hear if the car's VIN # was stamped on the block.
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From: Murrieta California
Car: 1969 RS Z28 X33 Norwood built
Engine: 383 Stroker
Transmission: T10 4 speed
Re: 1987 LG4, Roller or Tappet? Answered!!
I know one thing, Changing my water pump was no fun. Hopefully I'll never have to do that again.
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From: Macon, GA
Car: 1992 Camaro RS
Engine: Vortec headed 355, xe262
Transmission: T56
Axle/Gears: 9-bolt 3.70
Re: 1987 LG4, Roller or Tappet? Answered!!
Well even if it's not the original LG4 to the car, it's clearly an 87+ block. Only thing it needs is to get the holes for the spider drileld and tapped and probably the holes for the cam retainer plate drilled and tapped. My 350 block doesnt even have the dog bone perches machined the way this one does, but it's clearly an 87+ block with the pedestals.
My 350 block:

You can see the difference on the flats above the tappet guides.
Also, crafty, I hope you got all those bolts away from the intake ports by now.
My 350 block:

You can see the difference on the flats above the tappet guides.
Also, crafty, I hope you got all those bolts away from the intake ports by now.
Last edited by InfernalVortex; Dec 3, 2013 at 05:50 PM.
Joined: Mar 2000
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
I had an '87 LB9 complete engine in my early 3rd gen days. I pulled the intake, intending to port the heads. I discovered they were two different heads, even though both were of the '87-up intake bolt pattern. Posting the casting #s here on TGO, I was informed I had one LG4/LB9 head, and one LO3 head. So much for porting them. I pulled the heads, and further discovered I had a .030"-over 305 with roller cam/lifters, dished pistons - no, LB9s never came with dished pistons (we're talking full dish, deep enough that there weren't any valve reliefs). But, it started life as an LB9. (I later discovered it had cracks in the lifter valley, which made the whole thing scrap.)
It's more likely that a 27 year old car has a replacement engine in it than it is that it still has the original untouched engine in it.
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From: So. Ohio
Car: 88 Camaro
Engine: L98 350
Transmission: 700r4
Re: 1987 LG4, Roller or Tappet? Answered!!
Kind of looks like the lifters set deeper in the block too. Rollers might be longer/taller? I'd suspect the choice of roller or flat lifters might be an emissions deal.
Re: 1987 LG4, Roller or Tappet? Answered!!
The lifter bores are deeper on a factory roller (capable) block. However, you can drop flat tappet lifter & cam combo into them and they will function just fine. They look a little odd sitting WAY down in the lifter bore, but they function perfectly. I've done this a couple of times myself. So did the factory, as has been demonstated in this thread.
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From: Kelowna BC
Car: 87 Z/28
Engine: 5.0L
Transmission: T5
Axle/Gears: 9 Bolt posi
Re: 1987 LG4, Roller or Tappet? Answered!!
Well even if it's not the original LG4 to the car, it's clearly an 87+ block. Only thing it needs is to get the holes for the spider drileld and tapped and probably the holes for the cam retainer plate drilled and tapped. My 350 block doesnt even have the dog bone perches machined the way this one does, but it's clearly an 87+ block with the pedestals.
Also, crafty, I hope you got all those bolts away from the intake ports by now.
Also, crafty, I hope you got all those bolts away from the intake ports by now.
And yea, the bolts are put away lol
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Joined: Jul 2007
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From: Kelowna BC
Car: 87 Z/28
Engine: 5.0L
Transmission: T5
Axle/Gears: 9 Bolt posi
Re: 1987 LG4, Roller or Tappet? Answered!!
Well even if it's not the original LG4 to the car, it's clearly an 87+ block. Only thing it needs is to get the holes for the spider drileld and tapped and probably the holes for the cam retainer plate drilled and tapped. My 350 block doesnt even have the dog bone perches machined the way this one does, but it's clearly an 87+ block with the pedestals.
Also, crafty, I hope you got all those bolts away from the intake ports by now.
Also, crafty, I hope you got all those bolts away from the intake ports by now.
And yea, the bolts are put away lol
Joined: Dec 2005
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From: Macon, GA
Car: 1992 Camaro RS
Engine: Vortec headed 355, xe262
Transmission: T56
Axle/Gears: 9-bolt 3.70
Re: 1987 LG4, Roller or Tappet? Answered!!
If GM had no issue running the L05's with flat tappets, then I dont see why they wouldnt run the LG4's with flat tappets, especially since the LG4 is an engine that's been around since the late 70s with that configuration.
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Joined: Mar 2000
Posts: 43,187
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Joined: Dec 2005
Posts: 6,499
Likes: 31
From: Macon, GA
Car: 1992 Camaro RS
Engine: Vortec headed 355, xe262
Transmission: T56
Axle/Gears: 9-bolt 3.70
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From: Kelowna BC
Car: 87 Z/28
Engine: 5.0L
Transmission: T5
Axle/Gears: 9 Bolt posi
Re: 1987 LG4, Roller or Tappet? Answered!!
And I'm 99.9% sure the motor has never been touched, the car came to me 100% bone stock and in pretty rough shape from sitting for soooo long. lol didn't even look like anything other than an oil change was ever done...
Joined: Mar 2000
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From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
We're not talking casting number here. The VIN is stamped on the machined pad on the front passenger side of the block (same surface as the head gasket).
Joined: Aug 1999
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From: RI
Car: 1984 Camaro Berlinetta
Engine: LT1
Transmission: T56 6-speed
Axle/Gears: 4.11 LS1 Rear End
Re: 1987 LG4, Roller or Tappet? Answered!!
And I'm 99.9% sure the motor has never been touched, the car came to me 100% bone stock
I'm 99% the motor HAS been touched, I don't know about the internals,.... but that crank pulley sure looks like a pre-85 "true" V belt crank pulley. The Air Cleaner / Wheels are obviously aftermarket, the intake doesn't appear to be stock & niether is the fitting on the china-wall. It's also pretty clear that there's no way those are 25+ year old intake bolts.
I'm not saying the engine is this-or-that, but you'll need a pic of the (windshield) VIN and 1 pic of the VIN pad on the block is about the only "proof" people are gonna' accept.
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From: knoxville tn
Car: 86 IROC
Engine: 5.0 TPI
Transmission: 700-R-4
Axle/Gears: 2.73 open
Re: 1987 LG4, Roller or Tappet? Answered!!
+1 The first question that came to my mind.
I always assumed that all 87 engines were roller blocks with Self Aligning rocker arms till I was messing with some 87 TPI heads and learned that they (at least some) used non-SA rockers. However; I've never seen a non-roller 87 block.........
Welllllllllll,....... the 85-87 still used a "V" belt pulley system. The alternator belt simply changed from a true "V" belt to a ribbed belt. That change also changed the design of the WP pulley and crank pulley those years. There was still a seperate belt required for each accessory.

I always assumed that all 87 engines were roller blocks with Self Aligning rocker arms till I was messing with some 87 TPI heads and learned that they (at least some) used non-SA rockers. However; I've never seen a non-roller 87 block.........
Welllllllllll,....... the 85-87 still used a "V" belt pulley system. The alternator belt simply changed from a true "V" belt to a ribbed belt. That change also changed the design of the WP pulley and crank pulley those years. There was still a seperate belt required for each accessory.

Joined: Mar 2000
Posts: 43,187
Likes: 42
From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Okay, let's try one more time...
Self-aligning rockers didn't come until 1988.
Roller lifters were used in passenger car engines starting in 1987 to help meet government CAFE standards.
Flat tappet lifters were used in truck in block castings that were the same as passenger car block castings - i.e., roller-capable castings. Note that trucks didn't have to meet CAFE standards, therefore the factory saved the expense of the roller lifters in truck engines. Sometimes the roller provisions were machined/drilled/tapped in such truck engines, sometimes they weren't.
Unless you have owned an '87 LG4 passenger car since new, and/or have ALL service records from it, drawing conclusions based on disassembly 27 years later is not reliable.
Self-aligning rockers didn't come until 1988.
Roller lifters were used in passenger car engines starting in 1987 to help meet government CAFE standards.
Flat tappet lifters were used in truck in block castings that were the same as passenger car block castings - i.e., roller-capable castings. Note that trucks didn't have to meet CAFE standards, therefore the factory saved the expense of the roller lifters in truck engines. Sometimes the roller provisions were machined/drilled/tapped in such truck engines, sometimes they weren't.
Unless you have owned an '87 LG4 passenger car since new, and/or have ALL service records from it, drawing conclusions based on disassembly 27 years later is not reliable.
Re: 1987 LG4, Roller or Tappet? Answered!!
Five7kid- I'll reitterate what I said, above. Some flat tappet engines slipped through in 87. I've seen it myself on known-factory engines (in my case, an 87 TBI engine in an Camaro). It was a trasition year and nothing was set in stone.
Nobody believed me then, and apparently everyone is poo-poo'ing the possibility in this case, but it happened.
I don't know what to tell you beyond that other than "the assembly line isn't God" (it's not perfect).
Nobody believed me then, and apparently everyone is poo-poo'ing the possibility in this case, but it happened.
I don't know what to tell you beyond that other than "the assembly line isn't God" (it's not perfect).
Joined: Aug 1999
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From: RI
Car: 1984 Camaro Berlinetta
Engine: LT1
Transmission: T56 6-speed
Axle/Gears: 4.11 LS1 Rear End
Re: 1987 LG4, Roller or Tappet? Answered!!
Just a thing,...... gotta' see proof.
Never even heard of an 87 with serpentine and TB in a Camaro, I'm assuming that it was serpentine since they would have had to make a very custom harness for TBI and V-belt. Maybe there was such a thing; but I will not never believe it till I see proof. ( I gotta' ask; what was the VIN on that thing ?? )
In this case a very simple picture of the block pad and the Windshield VIN is proof enough and I'm sure it will get posted here if it exists. Honestly,..... So far there isn't even proof shown here that the car is even an 87. ( just sayin' ! ) It's just as easy to bolt a set of centerbolt heads on as is it to bolt down an intake - and that intake was NOT factory sealed.
I'm not tryin' to be a thorn or and certainly not calling anyone a lier. I don't know it all and even after 20 years under these hoods I still learn new stuff all the time. But I don't mind a healthy argument and if someone makes a claim that goes against the 'norm'........ I'll ask for proof.
I've seen it myself on known-factory engines (in my case, an 87 TBI engine in an Camaro).
In this case a very simple picture of the block pad and the Windshield VIN is proof enough and I'm sure it will get posted here if it exists. Honestly,..... So far there isn't even proof shown here that the car is even an 87. ( just sayin' ! ) It's just as easy to bolt a set of centerbolt heads on as is it to bolt down an intake - and that intake was NOT factory sealed.
I'm not tryin' to be a thorn or and certainly not calling anyone a lier. I don't know it all and even after 20 years under these hoods I still learn new stuff all the time. But I don't mind a healthy argument and if someone makes a claim that goes against the 'norm'........ I'll ask for proof.
Joined: Mar 2000
Posts: 43,187
Likes: 42
From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
Re: 1987 LG4, Roller or Tappet? Answered!!
Five7kid- I'll reitterate what I said, above. Some flat tappet engines slipped through in 87. I've seen it myself on known-factory engines (in my case, an 87 TBI engine in an Camaro). It was a trasition year and nothing was set in stone.
Nobody believed me then, and apparently everyone is poo-poo'ing the possibility in this case, but it happened.
I don't know what to tell you beyond that other than "the assembly line isn't God" (it's not perfect).
Nobody believed me then, and apparently everyone is poo-poo'ing the possibility in this case, but it happened.
I don't know what to tell you beyond that other than "the assembly line isn't God" (it's not perfect).
Does that mean a few didn't "slip through" with flat tappet cams? I'm not saying that didn't happen.
But to say ALL '87 LG4s got flat tappet cams because this one engine has them is problematic because: 1) you first have to have reasonable evidence that it came from the factory that way, and 2) even if it was factory flat-tappet equipped, that doesn't prove all '87 LG4s were.
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From: Kelowna BC
Car: 87 Z/28
Engine: 5.0L
Transmission: T5
Axle/Gears: 9 Bolt posi
Re: 1987 LG4, Roller or Tappet? Answered!!
well now i'm really damn curious. I may have to change the thread title if i can. Like I said, when I get home I'll post a picture of the numbers on the block and car (thanks for correcting me on casting vs vin on block five7kid)
as for the intake, that was me, like I said, when i got the car, the motor appeared to be all original. I tossed on some edelbrock stuff I had from my last Camaro.
Seems like I may have jumped the gun on assuming that just because mine is looking like a tappet cam, that all of them are... I was just soo tired of searching and searching for an answer, that I figured I would share my findings.
anyhow I'll still post up my findings with MY LG4, but i guess it comes down to just taking apart what you have to really find out.. shoulda bought an '88... lol
as for the intake, that was me, like I said, when i got the car, the motor appeared to be all original. I tossed on some edelbrock stuff I had from my last Camaro.
Seems like I may have jumped the gun on assuming that just because mine is looking like a tappet cam, that all of them are... I was just soo tired of searching and searching for an answer, that I figured I would share my findings.
anyhow I'll still post up my findings with MY LG4, but i guess it comes down to just taking apart what you have to really find out.. shoulda bought an '88... lol
Joined: Jan 2005
Posts: 10,403
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From: Hurst, Texas
Car: 1983 G20 Chevy
Engine: 305 TPI
Transmission: 4L60
Axle/Gears: 14 bolt with 3.07 gears
Re: 1987 LG4, Roller or Tappet? Answered!!
The point the OP was trying to make (at least the impression I'm gettting) was that '87 LG4s had flat tappet cams. There is plenty of evidence to counter that.
Does that mean a few didn't "slip through" with flat tappet cams? I'm not saying that didn't happen.
But to say ALL '87 LG4s got flat tappet cams because this one engine has them is problematic because: 1) you first have to have reasonable evidence that it came from the factory that way, and 2) even if it was factory flat-tappet equipped, that doesn't prove all '87 LG4s were.
Does that mean a few didn't "slip through" with flat tappet cams? I'm not saying that didn't happen.
But to say ALL '87 LG4s got flat tappet cams because this one engine has them is problematic because: 1) you first have to have reasonable evidence that it came from the factory that way, and 2) even if it was factory flat-tappet equipped, that doesn't prove all '87 LG4s were.
Its hard to see the lifter spider in all that mess, but its definately there.
Last edited by Fast355; Dec 19, 2013 at 09:28 PM.
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