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Discussion Starter #1
I tried a search on this but came up empty.
I have a 98 GMC with 320,000 km (roughly 200,000 mi) that I'm starting to have a few issues with. I also have a 95 GMC van with only 192,000 km (120, 000 mi). I've owned the van since new, so I know it's history. I don't need it anymore and was just planning on scrapping it when the thought came to me to pull the engine out of it, swap all my vortec stuff off the block in my 98 and then put it into the truck.
Do you see any issues with this?
My thinking is this; basically, I'm swapping the blocks. Everythng else stays the same in the truck: wiring, computer, manifolds - in and out(other than I'll upgrade to headers). Are there any sensors that are block specific (I'm wondering about the knock sensor on the 98)? Will I need to do a cam swap?
Anything you guys can think of prior to me starting this project would be of great help.
And please, no 'just swap in a Gen III' or '6.0 is the only way to go'. I understand what you are saying, I value that opinion and actually agree with you, but the thing is, I don't have a free 6.0 sitting in my backyard.
 

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everything should swap over i think the only thing they changed on the motors where the vortec heads intake and the tb the im pretty sure the trans will bolt right up the cam is a roller in both motors but some 305 350s came with out the roller motor but im pretty sure the trucks have roller cam if u where to swap out to a flat tappet cam u would have to change the timing chain lifters and pushrods cuz a roller cam has shoter push rods then the flat tappet cams everything else should bolt right onto the 95 block the only thing that was changed was the map tps and some other senors but it should go in with no problems a 6.0 swap would be really good but then u are looking into some money for a used 6.0 and then time swaping it all over to that motor
 

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Discussion Starter #4
Thanks guys!
What cam do you think i should use (I know there are 100's of threads on this topic, but I want you opinion). Obviously I can't leave the non-roller cam in the old block, and I don't think it would be wise to swap the cam out of the '98 block, or would that be fine too?
 

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I just took the intake off my '95 block, it has the provisions to go roller, but the block is not taped to screw down the deal that holds the roller lifters in place. I was told that it is easy whough to drill and tap the block. In your case is it worth all the effort when the 95 engine has quite a few miles also?
 

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HOT AIR BALLOON OWNER
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98 has better heads stock and I'd assume a better cam, I would still upgrade the cam while it's apart to something better. YES, go with a roller cam. Less trouble.

Rebuild the heads, they're great pieces.

Obviously reseal the rest of the block while it's apart. Replace that Spider fuel injection assy too.
 

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I would for sure try and run the L31 roller cam, lifters, pushrods in the 95 block. I would avoid the 95 camshaft in the 98 truck. L31 cam specs at 192º/197º .412"/.428" lift on a 111ºLSA

LO5 for under 7200 lbs GVRW(87-95 trucks engine "K", p/n 12520270)
9.25:1 compression, nodular iron crank, PM rods, dished hyper pistons,

CYLINDER HEAD SPECS:
-CASTING NUMBER 14102193
-SWIRL PORT INTAKE PORT DESIGN
-64cc COMBUSTION CHAMBER
-1.94" INTAKE 1.50" EXHAUST VALVE
-VALVE SPRING PART NUMBER IS 3911068 (SAME SPRING USED WITH THE OLD 300H.P 350 CRATE)
-INSTALLED HEIGHT 1.70" PRESSURE @ INSTALLED HEIGHT IS 80 LBS * PRESSURE WITH VALVE OPEN IS 267 LBS.
-THESE SPRINGS ARE GOOD FOR .550" LIFT BUT CLEARENCE BETWEEN GUIDE AND RETAINER MUST BE DOUBLE CHECKED BEFORE ATTEMPTING.
-7 BOLT EXHAUST FLANGE
-CENTERBOLT VALVE COVER FLANGE
-1987-1995 INTAKE MANIFOLD BOLT PATTERN WITH CENTER INTAKE BOLTS CANTED @ 72 ANGLE

THIS CYLINDER HEAD IS NOT A PERFORMANCE ORIENTED CYLINDER HEAD. IT IS CLASSIFIED AS A HIGH SWIRL HEAD THAT WAS INTENDED FOR GOOD BOTTOM END TORQUE AND FUEL ECONOMY. THE INTAKE RUNNER IS RESTRICTIVE BECCAUSE IT HAS A RAMP CAST INTO THE BOTTOM OF THE BOWL TO PROMOTE HIGH SWIRL.


LO5 for 8600+ lbs GVRW (87-95 engine code "K", p/n 12568758) also used in the 1996-2002 "P" Van 3/4 and 1 ton applications.
8.75:1 compression, nodular iron crank, PM rods, dished hypereutectic pistons

CYLINDER HEAD SPECS:
-CASTING NUMBER 14102191
-SWIRL PORT INTAKE PORT DESIGN
-76cc COMBUSTION CHAMBER
-1.94" INTAKE 1.50" EXHAUST VALVE
-VALVE SPRING PART NUMBER IS 3911068 (SAME SPRING USED WITH THE OLD 300H.P 350 CRATE)
-INSTALLED HEIGHT 1.70" PRESSURE @ INSTALLED HEIGHT IS 80 LBS * PRESSURE WITH VALVE OPEN IS 267 LBS.
-THESE SPRINGS ARE GOOD FOR .550" LIFT BUT CLEARENCE BETWEEN GUIDE AND RETAINER MUST BE DOUBLE CHECKED BEFORE ATTEMPTING.
-7 BOLT EXHAUST FLANGE
-CENTERBOLT VALVE COVER FLANGE
-1987-1995 INTAKE MANIFOLD BOLT PATTERN WITH CENTER INTAKE BOLTS CANTED @ 72 ANGLE


Flat tappet cam specs for BOTH LO5 applications:
165.9º/174.8º duration @ 0.050" lift .382"/.402" 111.9ºLSA

INTAKE VALVE OPENS @ -30.2 BTDC * INTAKE VALVE CLOSES @ 16.1ATDC * INTAKE LOBE CENTERLINE - 111.8

EXHAUST VALVE OPENS @ 18.1BBDC * EXHAUST VALVE CLOSES @ -23.3 ATDC * EXHAUST LOBE CENTERLINE - 111.8


So pretty much take the 95 block, tap the 3 bosses to make it OEM roller cam/lifter ready
-instal the L31 4x reluctor wheel onto the 95 LO5's crank
-install 1996-2002 plastic front timing cover over the L31 timing chain/sprockets-install crank position sensor into the Vortec plastic front timing cover
-install Vortec heads onto LO5 block
-install Vortec intake manifold torque to 11 lb/ft on the intake bolts
-drop in Vortec distributer

I think thats most of the Vortec specific stuff, once theengine is buttoned up, set the Camshaft Position Sensor retard (CMP Retard) to ZEROº plus or minus 2º by clocking the distributer with a scan tool that reads CMP Retard.
You MAY need to do a CrankShaft Angle Sensor Error Relearn(CASE or crank Relearn), and if the PCM tune is setup properly (if you decide on non-stock cam) the truck should start up and run just fine.


I do agree with Hitman, since the cam will allready be out, I would look into getting a different roller cam.
For GM cams there is the
10185071-ZZ4 cam 208º/221º .474"/.510" 112ºLSA Its used in the 355hp ZZ4 crate engines

12551142-LT4 Production cam 203º/210º .476"/.480" (with 1.6:1 rockers)
on a 115º This was used in the 1996 LT4 Corvettes and the rare 1997 LT4 Camaro and Firehawk cars. The LT4 was rated at 330hp at 5800rpm and 340 lb/ft torque and has a fuel shuttoff of 6412rpm. the LT4 has LS1 power in the older GEn 2 engine configuration.

14097395-Ramjet 350/HT383/marine roller cam 196º/206º duration at 0.050"
.431"/.451" lift on a 109ºLSA This would be a small step up from the stock Vortec 350/305-B-Body Iron head LT1 5.7-1994-96 4.3L V8 L99 camshaft.

24502586-LT4 Hotcam 218º/228º 0.525"/.525" 112ºLSA Used in LT1/4 Vettes as part of SCCA showroom stock class racing.

These are just the more common GM roller cams that get swapped into Vortec 305/350 engines.

then there are the 3 GMPP cams that are ground by and use Crane(IIRC) profiles.

12370845- 214º/224º .488"/.509" 112º LSA
12370846- 222º/230º .509"/.528" 112º LSA
12370847- 234º/242º .539"/.558" 112º LSA

I like the Lingenfelter roller cam P/N L210025087 specs of 213º/219º .493"/.502" on a 112º LSA.

When looking for cams, cams that fit LT1 enines also will work in the Vortec engines, and in your 95 LO5 engine with Vortec heads. Just look for cams that fit GEN1, GEN1E or GEN 2 engines.

peace
Hog
 

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Discussion Starter #8
All I can say Hog is...Wow!
That is an awesome amount of information, and exactly what I needed (torque specs and all...wow!).
To everyone that has replied so far...thanks a bunch. It's guys like you that make the internet, forums and expecially this forum what it should be. Informative. Plus you make me proud to own a (north) American made peice of iron, let alone a GM.
Thanks again. I will process this all and let you know what I'm gonna do, but please don't stop the info...this is great.
At this point, I'm defineitly upgrading the cam.
Hey Hog, what makes you lean towards the Lingerfelter?
 
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