The situation I am in is with a 1991 SBC 350 from a 1500 fullsize pickup.. I purchased the engine from A GUY who said it "was built by a race car driver" and has a hydralic cam... woah!! Right? LOL Not really... I installed my 1990 Camaro Tuned port with 52mm throttle body, fully ported intake and LT1 injectors.. 1 week after installing a new 700R4 I have needed since before the TPI install.. I spun a bearing.. .. Now it is time to rebuild the motor.. I am wanting to install the stock Cam from the L98 motor.. My motor does not have the provisions for the roller cam.. All I know is... I will have to tap my motor in 3 places for the screws from the spider.. I have the spider, wishbones and lifters.. My question to everyone ---> What all do I have todo to convert to a roller cam?

I think you need retrofit lifters since the spyder has bosses for the bolts and the lifter bores have retaining plates that fit on top to keep the lifters from moving.

I dont think a nonroller block has that feature so the retrofit lifters are needed, and no spider i believe.

The roller cam uses a thrust plate/retainer plate on the front of the block. Non rollers i believe do not have that feature as well, and need a thrust bushing of some sort on the timing cover to keep the cam from walking forward. L98 cam has a stepped nose as well and will require a roller timing set for OEM hydraulic roller cam motor. I believe you can use a thrust bushing on that style timing set but I'm not 100% sure.

Others who have done this stuff before can further comment

I need some answers for the same question, got a 350 non roller block to the bare and a 305tpi from a 91 camaro. I want to run a lt4 cam in the 350 and will be getting new lifters and rockers already got l98 aluminium heads.

Some have ground out the block in order to fit the factory style lifter retainers ( dogbones ) and tapped the valley for the hold down spider and the block for the cam retainer plate at front.
Inside of valley needs to look like this; notice the flat surface above the lifter bores for the dogbones to sit on?



Easiest ( not cheapest ) is to buy retro fit lifters that don't require factory style spider.
You need this to fill the groove on the factory cam
http://www.lingenfelter.com/mm5/merc...egory_Code=C30
and a roller timing set because the bolt pattern on roller cams is different to non roller

It almost certainly has a hydraulic cam, you must be confusing hydrolic and roller since they are two different definitions. A roller can be either solid or hydrolic and the same goes for a flat tappet setup.

If it's aroler cam block with a flat tappet cam then you can use OE equipment with some work, if it isnt like the pic above then it's best to go aftermarket or just use flat tappet parts.

Thanks for the advice, sounds like it's not too much work and the roller timing set and cam button is pretty inexpensive the lifters I was planning to get new ones anyways and tapping the block I will get a shop to do.I dont wan't to take a chance building a non roller and having problems with it down the road just wan't it done right the first time.

If you have a roller block that capable of taking a factory spider and dogbones then it can also be fitted with a factory cam retaining plate as well. More drilling and tapping if the block isn't already machined for it, but the bosses are there, just like up in the lifter valley. No need for an aftermarket cam button.

If it's an earlier non-roller cam block you need aftermarket stuff. Aftermarket roller lifters with the tie-bars between them, cam button, etc. Not a cheap upgrade.

In the first part did you mean a non-roller block capable of taking a factory spider and dogbone, my block is a non-roller 92 truck block i have some pictures of it in another thread.I dunno what the spider and dogbones are I can post some pictures of the block with the lifter valley and everything. The roller lifters with the tie-bars are pretty expensive the cheapest set I saw on summit was around 280 and the rest are around 500.

No he means that after 87 many blocks were cast to accept roller cam setups but were equipped with flat tappet's instead, it's still a "roller block" just with a non roller valvetrain.

Oh I see I may be in luck then so if the area ontop of the lifter bores is flat that can hold the spider and the dogbones and I just have to tap the block for the plate that will hold the cam in place.I'll be back with some pictures hopefully someone can identify if my block is a roller

All of the roller blocks I have seen have been fully machined and threaded for the roller cam setup even if a flat tappet cam was installed at the factory ( common early '90's truck engines )

I was told my block doesn't have the threads for the plate in another thread here are the pictures.http://www.thirdgen.org/techboard/te...-if-block.html (How to tell if block is roller or flat-tappet)

Heres the lifter valley

I'm pretty sure the block did come from a 91-92 truck or I could be wrong, it did have the centrebolt valve covers and appearance of a L98 block.Should I get the numbers off the block and heads and get to the bottom of what kinda block it is?

It is a non roller block ;
no posts cast in the valley for the spider plate , no machining above the lifter bores for the lifter dogbones .Compare valley with my pic above
Nothing to say it hadn't been changed out for another short block using the original C/b heads.
Any letter codes on the front block pad?

I can check it but it's clear its not a roller so I guess the retro lifters,cam button and timing chain is the only way I can do it that's all I really wanted to know, thanks for the help, this project is fighting me the hole way.

You dont have to convert to a roller block unless you got your heart set on it.I got 86 4 bolt block I plan on stroking it and running hyd flat tappet cam,16 rockers,dbl timing chain.im hoping for over 400hp at the flywheel and still safe and reliable.If you match your parts right..the block and bottom end will be strong..just takes more time research and patience..which will in the end..save you money instead of throwing parts at it and then changing them out.

What do you plan to do with this motor build and what rpm are you realistically going to spin upto? I know i may hit 6500rpm time to time with my 383 build using afr 190 heads but on a daily basis.iiIll probably spin upto 55-5700 if I beat it a lil which is just fine.

if your aiming for big numbers and very snappy response and a high revving block then id lean towards spending the extra money and converting the block..its a good reassurance. Just my opinion though.

If your heart is set on a roller cam sell your block andbuy a roller cam block .The cost difference would be cheaper than buying the retro fit lifters alone and you get to use all OEM parts Vortec truck blocks '96-'00 are common and cheap.

I will try that if not I may just build this with a flat tappet if it gets to pricey.

An aftermarket roller conversion for your non-roller block is expensive- proably close to $1000 when you add it all up. Plus having to set up the cam button clearance, which often gives novices fits as well.

A flat tappet cam and lifters plus a new chain is going to be less than $200, even for all new brand-name stuff.

Of course, you don't have to worry much about flattening cam lobes during break-in with a roller, but the HP-per-dollar on a roller cam conversion is usually not good for a modest street performance engine. Money better speng on things like better cylinder heads, etc.

Or, if your heart is set on a roller cam, sell your current block and buy a used factory roller cam block. Both sell for about the same money in the used market. And you might just be able to buy it with all the roller cam stuff still in it- spider, dogbones, lifters, retaining plate, etc.

You have some good points there for a street performance engine it may not be worth all the trouble, I found some cheap retro rollers compared to the rest on the market http://www.summitracing.com/parts/HRS-91164N/ dunno how good they will be but the rest of the parts I would need for the conversion would'nt cost too much. I would try selling my block but that will take a lot of time and the market for auto parts these days is crap. I can just build it up with a flat tappet cam save some money and enjoy the car its a summer driver anyways, I wouldn't know what cam to choose if I go this route but I guess its research time.Thanks for all the help.

You CAN convert your none roller block to accept factory Chevy roller hydraulic lifters very inexpensively!!!!

You will need to grind the block so the dogbones will lay flat and drill a tap two holes to hold the spider in place. Loctite them in place, you will need to use Chevy 3.1 V6 lifters which are shorter and a custom length pushrod.

My brother and I did this to his 78 Chevy pickup and it runs great!!

Yes you will have to use a cam button and the lifters, dogbones and spider plate can be purchased from ebay for around $100.

We measured the pushrod and just searched my machinist catalog for a match which turned out to be Buick pushrods that cost us $30 bucks. I can find the receipt if anyone would like the size and part number but I would recommend checking it, it is very easy.

I think it is a very worth while investment because of all the flat lifter failure and having to redo the entire engine is not fun and dumping all that metal into the engine does damage your bearings.

The pics of your block seem to have the needed dogbone clearance needed.

Feel free to contact me about this conversion.