Putting a Caprice engine (L05-7) into a 92 g30 van (has L80e trans)

[L31MaxExpress]

OK so now I have an engine to work with.
My “old” G30 (91) engine I just pulled to put into my “new” G30.

The engine was misfiring on #5 even after new plugs and wires and had a pronounced lifter tic.

The plan is to put in a roller cam.
This is what I have:
- Roller ready
- 4 bolt main
- 2 piece rear seal
- Double roller timing chain

Block. - 14093638
Heads - 14102191
Intake - 14102182

Spares I could use:
- Heads - 110110810
- Intake - 10093015

- I’m looking for close enough to stock to minimize complications.
Questions:
1) Will I need to change the valve springs?
2) Will I need to change the distributor gear?

The 810 heads flow a little better stock for stock. Ideally you want to delete the valve rotators, install the approriate retainers and shims in their place and put a little stiff valve spring. I have used GM performance Z/28 springs on them. Saw they were on sale for under $3.00 a spring the other day.

I would use the Summit 8800 or GM 7395 cam for the high idle vacuum, smooth stable idle, and stump pulling low-midrange torque they make. Van's need a lot of torque to get them rolling, accelerate them and keep them rolling uphill and into a headwind especially loaded or towing.

 

[Danboquist]

Thank you for the info. The engine is a flat tappet TBI. I will need a new timing set and new springs.
I guess when I ask about what cam I can find out about the springs.
All that I have to do now is pick a cam.
Thanks!

 

[Schurkey]

The button head roller cams use a different timing gear with a smaller center hole

And smaller bolt-circle. A flat-tappet cam gear cannot be bolted to a step-nose (OEM-style) roller cam.

 

[International47]

On the 810 heads, I found that GM cut the spring seats lower to make up the room for the rotators on each valve.
Without the rotators and using a stock retainer, the installed height is 1.80.. perfect height for stock Beehive springs.

the only crappy part is you will need to use a set of outside spring cup, locators and have the centers drilled out to fit over the factory guide bosses. and a set of comp beehive retainers.
The locators are cheap, and come in varying thickness...... which will make the new installed height of the Beehive springs shorter and with it spring pressures closer to the z28 springs.

 

[Danboquist]

You have a timing gear from a roller cam or a flat tappet? The button head roller cams use a different timing gear with a smaller center hole

Edit: here's a roller cam timing set on top and a flat tappet one below.

You must be registered for see images attach

Mine is a flat tappet timing chain. Added this to the list..

 

[Danboquist]

I'm still working on doing "research" on valve spring stuff. It seems what I'm looking at are springs with .550 max lift and stock OD of 1.25 or so. It's the stuff that goes along with the springs (retainers, seats, pushrods, rockers) that get complicated... esp. because I haven't got a fix yet on what the object/goals is/are besides a heavy duty spring. I didn't find the GM springs yet, but the Howards springs look like the basic idea..

Anyway, this is the first stab at a parts list:

Roller Cam https://www.summitracing.com/parts/sum-8800 $280

Roller Lifters https://www.summitracing.com/parts/SUM-HT21416 $173

Thrust Plate and Screws https://www.summitracing.com/parts/nal-12371043 $103
Timing Chain ………………………………………………………………………...........................

Springs https://www.summitracing.com/parts/HRS-98212 $77

Spider/Dogbones https://www.summitracing.com/parts/sum-150123 $88

Gaskets https://www.summitracing.com/parts/fel-260-1269/make/chevrolet/model/g30/year/1991 $135

Pushrods? (diameter, length) ~ $150.00

Distributor Gear? ~ $100

Spring Retainers, seats

------------

$ 856

 

[Schurkey]

I haven't got a fix yet on what the object/goals is/are besides a heavy duty spring.

You need a spring compatible with a roller cam.

I didn't find the GM springs yet, but the Howards springs look like the basic idea..

According to the Summit web page, they're intended for flat-tappet cams.

Is that a big deal? Maybe, maybe not. Kinda thinking that roller-cam springs have more closed pressure than flat-tappet springs, to assure that the roller keeps rolling instead of skidding on the cam lobe. But I'm not a cam/lifter/spring/retainer expert.

Anyway, this is the first stab at a parts list:

Roller Cam https://www.summitracing.com/parts/sum-8800 $280

Roller Lifters https://www.summitracing.com/parts/SUM-HT21416 $173

Thrust Plate and Screws https://www.summitracing.com/parts/nal-12371043 $103
Timing Chain

Okay.

Springs https://www.summitracing.com/parts/HRS-98212 $77

Probably not my first choice.

Spider/Dogbones https://www.summitracing.com/parts/sum-150123 $88

Gaskets https://www.summitracing.com/parts/fel-260-1269/make/chevrolet/model/g30/year/1991 $135

Head gaskets are going to be much too thick for proper squish/quench, unless you zero-deck the block instead of merely square-decking.

Pushrods? (diameter, length) ~ $150.00

How are the pushrods/rocker arms guided? If you're using self-aligning rockers, or the oval holes in cast-iron heads, you can probably use the stock pushrods.

If you're using pushrod guideplates, you MUST use hardened pushrods. Upgraded pushrods are a nice upgrade no matter what method is guiding the pushrods/rockers.

Pushrod length is the LAST thing you check when assembling a long-block. There's too many variables in the assembly that can affect pushrod length. OTOH, it's a fair bet that stock length will be fine.

Distributor Gear? ~ $100

WHAT DISTRIBUTOR ARE YOU STARTING WITH? If you're using a TBI or Vortec distributor, and the gear isn't worn-out...just re-use it.

Spring Retainers, seats

"Seats"??? Do you mean "seals", which should be part of your gasket set?

The retainers will have to match the springs you select. The springs should match the cam. How about a cam/lifter/spring/retainer/keeper set sold as a kit by the same supplier? Pretty-much guaranteed to all work together.

Depending on how things stack-up, you may or may not want valve keepers to adjust the installed height by + or - .050.

Similarly, you may or may not need valve spring shims for adjusting spring installed height.

 

[Danboquist]

You need a spring compatible with a roller cam.


According to the Summit web page, they're intended for flat-tappet cams.

Is that a big deal? Maybe, maybe not. Kinda thinking that roller-cam springs have more closed pressure than flat-tappet springs, to assure that the roller keeps rolling instead of skidding on the cam lobe. But I'm not a cam/lifter/spring/retainer expert.


Okay.


Probably not my first choice.


Head gaskets are going to be much to thick for proper squish/quench, unless you zero-deck the block instead of merely square-decking.


How are the pushrods/rocker arms guided? If you're using self-aligning rockers, or the oval holes in cast-iron heads, you can probably use the stock pushrods.

If you're using pushrod guideplates, you MUST use hardened pushrods. Upgraded pushrods are a nice upgrade no matter what method is guiding the pushrods/rockers.

Pushrod length is the LAST thing you check when assembling a long-block. There's too many variables in the assembly that can affect pushrod length. OTOH, it's a fair bet that stock length will be fine.


WHAT DISTRIBUTOR ARE YOU STARTING WITH? If you're using a TBI or Vortec distributor, and the gear isn't worn-out...just re-use it.


"Seats"??? Do you mean "seals", which should be part of your gasket set?

The retainers will have to match the springs you select. The springs should match the cam. How about a cam/lifter/spring/retainer/keeper set sold as a kit by the same supplier? Pretty-much guaranteed to all work together.

Depending on how things stack-up, you may or may not want valve keepers to adjust the installed height by + or - .050.

Similarly, you may or may not need valve spring shims for adjusting spring installed height.

I missed that those springs were for flat tappet. It seems like the general idea is that roller springs can be had with the same OD as the stock and with a .550 lift.
I’m trying to figure out the correct questions about the valve train issues..
I’ll search for a set like you mentioned.
Should/must I get new rocker arms? Stronger ones?

I appreciate the information.

 

[Schurkey]

Should/must I get new rocker arms?

No. This assumes that the rockers you have are not worn-out, and that's not a good assumption.

In general, a person will need three or four sets of used rocker arms to make one good set from--if it's even possible.

The chances are very high your rockers have excessive wear. But there's no way to know until you pull 'em off and look. Keep the rocker balls matched to the rockers they're on--don't mix 'em up. You'll be looking at the end that contacts the valve tip, the end with the pushrod socket, and the pivot-ball area. A defect in any one of those areas disqualifies the rocker from further service.

USUALLY the problem is at the valve-tip end.

Stronger ones?

At the cam lift and valve spring stiffness you're planning, "stronger" rockers aren't needed. Many aftermarket rockers are lower-quality than OEM, good for nothing but moving your money into someone else's pocket. HIGH QUALITY "stronger" rockers might be desirable, but not necessary.

Forget "roller tip" rockers. Either use stock rockers, or move all the way to full roller rockers, preferably steel (Comp Cams or Crower) rather than aluminum.

 

[Danboquist]

No. This assumes that the rockers you have are not worn-out, and that's not a good assumption.

In general, a person will need three or four sets of used rocker arms to make one good set from--if it's even possible.

The chances are very high your rockers have excessive wear. But there's no way to know until you pull 'em off and look. Keep the rocker balls matched to the rockers they're on--don't mix 'em up. You'll be looking at the end that contacts the valve tip, the end with the pushrod socket, and the pivot-ball area. A defect in any one of those areas disqualifies the rocker from further service.

USUALLY the problem is at the valve-tip end.


At the cam lift and valve spring stiffness you're planning, "stronger" rockers aren't needed. Many aftermarket rockers are lower-quality than OEM, good for nothing but moving your money into someone else's pocket. HIGH QUALITY "stronger" rockers might be desirable, but not necessary.

Forget "roller tip" rockers. Either use stock rockers, or move all the way to full roller rockers, preferably steel (Comp Cams or Crower) rather than aluminum.

Might as well go with new rocker arms and pushrods..