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roller cam retro fit

8K views 14 replies 8 participants last post by  BogiesAnnex1 
#1 ·
Building a 1974 350 and bought a zz4 cam is there any way to make it work the back spacing on the cam gear is wrong and I'm stuck I've done bought my retro lifters roller rockers push rods cam button is there any thing I can do to make up the difference from not having a retainer plate or do I need to take out a loan to buy a retro roller cam thanks Darin
 
#3 ·
DoubleVision said:
You`re best bet here I think would be to just go ahead and get a retro roller cam, you might find one on ebay, If you try and make the ZZ4 cam work, you`ll spend just as much in machining and hassle.

What DV said......... You already have the retro lifters and they're more expensive than the cam. Pony up for the retro cam and put the ZZ4 on eBay.
 
#5 ·
Roller Cam Retro Fit

Thanks for your feed back after getting a retro fit cam do you recomend a timing chain with a wear plate or a roller bearing or nothing. I've never had the money to build a good motor and don't wont to half a** it. I know its only a suburban but got to start again some where.
 
#6 ·
Retro Roller Info

I'm sure this is probably too late but, You can use your rear cam plugs position to align the cam gear or do what I do and make a spacer the same specs as the front retainer plate minus mounting lugs. (You must use a cam button that has been machined down to fit the roller cam gear)and Allen Head screws for mounting cam. Hex Heads are too large and will hit the button. Liquid threadlock on screw threads.
O.D.=2.75, I.D.=1.568 +or-.002, Thickness=.136 +or-.002,
You also need 4 Oil Groove slots from OD to ID on front face .0625=1/16" deep.
Welcome,
 
#7 ·
I thought about using the ZZ4 cam in an early block also but didn't think it would be such a headache. SSedan64 sounds like he has the fix for this but I can't picture what the spacer would be needed for. If the newer style timing setup is used can't a cam buttun just control the location without the need for a retainer plate? Bob
 
#8 · (Edited)
Retro Roller

You don't have to use the spacer. It's just extra insurance. Some worry about the cam rubbing a hole in the rear cam expansion plug from using it to align the timing gears. With the spacer the cam never touches the rear plug and it keeps the timing gears aligned. Rollers don't really have any rear thrust like flat tappets, they just float a little. The rear of the cam gear rides against the spacer like in a Factory roller block. If the engines a race only that's pulled frequently you can keep a close eye on the rear plug if not usuing the spacer. Also you can use a factory rollercam retainer with the mounting tangs trimed off.
 
#9 ·
I've done a late model roller cam retrofit (98 Z28) into a '66 327 block based on detailed photo's and descriptions I picked up off of ebay a few years back (I think; it's been a lonnnnng term project). SSendan64, sounds like you might even be the author based on the description of the spacers.

Anyway it uses GM 4.3L hydraulic lifters and involved some minor grinding here and there. I'm setting the engine up on a test stand to break it in. Will be interesting (to say the least) to see how things work out, since this is very eclectic and not in any book.

Rich
 
#10 · (Edited)
Roller Info

itstorque said:
I've done a late model roller cam retrofit (98 Z28) into a '66 327 block based on detailed photo's and descriptions I picked up off of ebay a few years back (I think; it's been a lonnnnng term project). SSendan64, sounds like you might even be the author based on the description of the spacers.

Anyway it uses GM 4.3L hydraulic lifters and involved some minor grinding here and there. I'm setting the engine up on a test stand to break it in. Will be interesting (to say the least) to see how things work out, since this is very eclectic and not in any book.

Rich
I'm not the Author. Same place I got most of the Info though. I've done 2 of these so far. 406 with ZZ4 & 355 with RamJet 350 cam for cheap from Ebay. Both into NonRoller blocks. The lifters I used were the 2.2L4, 3.1 & 3.4V6. Hard to beat the price $75 for Spider/Retainer,Guides,& New Lifters--TheAllChevyShop Ebay Store. Both engines are running good so far. About 15,000 mi on the 355. Keepin my fingers crossed. :thumbup:
 
#11 ·
Well, I'm a little relieved to hear from someone who did it besides the author.

How would you rate the result relative to the effort and relative to flat tappet cam engines?
What are some of your other specs? Comp ratio, chamber cc, carb?

I'm really interested in the exhaust system you've chosen. Can you tell me what you chose and how it sounds. My 327 is going in a Porsche 911, and not much distance to work with there but I don't want a really load sound.

Rich
 
#12 · (Edited)
itstorque said:
Well, I'm a little relieved to hear from someone who did it besides the author.

How would you rate the result relative to the effort and relative to flat tappet cam engines?
What are some of your other specs? Comp ratio, chamber cc, carb?

I'm really interested in the exhaust system you've chosen. Can you tell me what you chose and how it sounds. My 327 is going in a Porsche 911, and not much distance to work with there but I don't want a really load sound.

Rich
Happy so far, Is your 911 RearEng?
The 1st time RamJet350cam= ((intake/exhaust) is 288/308; dur @ .050" (intk/exhst) is 196/206 lift (intk/exhst) is 431/451. lobe c/l 109 degrees)) was alot more time consuming. Mainly just cautious clearancing for the guides. It's 72ChevyC10 Trk, SBC350,THM2004R,12Bolt3.73,9.0-1 Comp.Ratio mostly stock, Performer carb/intake/dualExhst very smooth runnnig,15,000mi so far. The stock cam was about same Dur. W/less lift. 2 MPG more & little more HP.
2nd 64ChevelleSBC406, 10-1CompRatio AlumHead,220ccIntk.Rnr.,64ccChbr, -20cc Rev.DomePistons,6"Rods, VictorJr Intk, Holley770cfm,3"Full Exht.THM2004R, 12bolt3.73,ZZ4Cam Dur.@.050"Lift:208/221 Lift.474"/.510" Lobe Sep 112
Haven't Quite finished it. Thinking about swapping RamJet cam forZZ4 & getting larger cam for 406. ZZ4 is way to small for the 406 with my heads.
I've got a few other tips #1- A guy in Fl. Mounted his Spider using the holddown springs from a lifter valley baffle tray instead of bolts/studs. I haven't tried this but he said no worries.
#2- Go to www.gmperformanceparts.com & search for Part#88958652 "Quick Cam" ValveLifterGuide this is (Very) nice for swapping cams without removing intake or lifters!! or /www.gmpartsdirect.com you have to download a 30MB catalog to see a Pic of it a the first site.
 
#13 ·
DARIN ALLMAN said:
Building a 1974 350 and bought a zz4 cam is there any way to make it work the back spacing on the cam gear is wrong and I'm stuck I've done bought my retro lifters roller rockers push rods cam button is there any thing I can do to make up the difference from not having a retainer plate or do I need to take out a loan to buy a retro roller cam thanks Darin
Yes, but first let me dump a little background.

The ZZ4 cam and all factory passenger car and some truck cams since 1987 are for the OEM roller config which uses block modifications; these being taller lifter blocks, cast and machined bosses on the main oil galley that mount an eight legged spider used to retain pair wise sets of bars that hold the roller lifters in alignment. The front of the block is modified to accept a cam retention plate that bolts on with 2 bolts to a pad added around the face of the front cam bearing. This requires a cam with a machined nose the thickness of the plate. The cam's timing gear hub is modified to accommodate the additional thickness of the plate and cam nose without moving it's position relative to the crank gear.

The solution on the front is to purchase the thrust plate and cut its ears off and to use the timing set for the OEM roller engine with a cam button to retain the roller cam.

But in the bigger scheme, while there are people who modify non roller blocks to roller use, it requires drilling and tapping into the main oil galley for spider retention bolts, this really isn't thick enough for the loads, and passing the bolt thru the oil galley would significantly reduce oil flow. The lifter blocks are also about 1/4 to 3/8s inch too short to adequately support OEM rollers. So I can't really recommend trying to put an OEM roller into a non-OEM roller block, just too many iffy compromises to suit me.

Now you could use aftermarket roller lifters but these are rather expensive. So by the time you do all this messing around, you might just as well pick up a roller block. For 350 roller tappet blocks look for casting numbers 10243880, 14011148, 14088526, and 14093638. The 880 is pretty common as it's the Vortec truck block.

Bogie
 
#14 ·
NonRoller Block

oldbogie said:
Yes, but first let me dump a little background.

The ZZ4 cam and all factory passenger car and some truck cams since 1987 are for the OEM roller config which uses block modifications; these being taller lifter blocks, cast and machined bosses on the main oil galley that mount an eight legged spider used to retain pair wise sets of bars that hold the roller lifters in alignment. The front of the block is modified to accept a cam retention plate that bolts on with 2 bolts to a pad added around the face of the front cam bearing. This requires a cam with a machined nose the thickness of the plate. The cam's timing gear hub is modified to accommodate the additional thickness of the plate and cam nose without moving it's position relative to the crank gear.

The solution on the front is to purchase the thrust plate and cut its ears off and to use the timing set for the OEM roller engine with a cam button to retain the roller cam.

But in the bigger scheme, while there are people who modify non roller blocks to roller use, it requires drilling and tapping into the main oil galley for spider retention bolts, this really isn't thick enough for the loads, and passing the bolt thru the oil galley would significantly reduce oil flow. The lifter blocks are also about 1/4 to 3/8s inch too short to adequately support OEM rollers. So I can't really recommend trying to put an OEM roller into a non-OEM roller block, just too many iffy compromises to suit me.

Now you could use aftermarket roller lifters but these are rather expensive. So by the time you do all this messing around, you might just as well pick up a roller block. For 350 roller tappet blocks look for casting numbers 10243880, 14011148, 14088526, and 14093638. The 880 is pretty common as it's the Vortec truck block.

Bogie
Hi Bogie, It's a little work but it actually works great. The bolts/studs go just to the inner edge of the oil gallery. I Epoxy around the jamnut also. Also the 2.2 L4, 3.1V6,3.4V6 Roller lifters are .200 shorter than V8 Rollers do that takes care of most of the lifter boss Diff. Send me an email and I'll send the RetroRoller Instructions AdobeAcrobat 3.5MB file 55pages.
 
#15 ·
SSedan64 said:
Hi Bogie, It's a little work but it actually works great. The bolts/studs go just to the inner edge of the oil gallery. I Epoxy around the jamnut also. Also the 2.2 L4, 3.1V6,3.4V6 Roller lifters are .200 shorter than V8 Rollers do that takes care of most of the lifter boss Diff. Send me an email and I'll send the RetroRoller Instructions AdobeAcrobat 3.5MB file 55pages.
I have done a few of these over the years and am not pleased with the results either from a cost nor longevity stand point.

It's one thing to do it in your garage to see if you can, but as a builder, it's more time thus cost than I have and customers can afford.

All the mods from grinding clearance in the valley walls for dogbone clearance to warranty concerns where 4 or 5 threads in cast iron is all that's holding the spider on. The potential for a failure here keeps me awake at night. Fitting the OEM thrust plate requires drilling and tapping into a water jacket and hoping the 3-4 threads will hold the plate and not leak coolant into the engine, something else that gnaws in the back of my mind. One can always make a thrust spacer and use a button to control end thrust, then your back to all the pain of traditional thrust buttons; getting them set up, providing a sufficiently stiff surface for them to ride against, the sometimes high wear rate I see on some engines. Then the little motor lifters don't seem to hold up well to stiff springs, heavy valves, and high RPMs. Those things are little bombs that have proven to be just a matter of time till one lets go and takes the cam with it.

So in my experience with roller blocks so cheap and plentiful, why bother with retofitting old blocks unless your trying to preserve a numbers matching chassis and engine in a world with out ZDDP in the oil.

Bogie
 
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