Which one? Roller or Flat Tappet cam ?

[turbo1962]

Building a 87 GN motor, which way should i go ,on the cam? roller or flat tappet? what are the advantages & disadvantages.TE 61 turbo and 3200 stall
daily driver. Anyone have something for sale roller? :biggrin:

 

[blown okie]

Roller!!

 

[Otto J]

GO Roller!
If for no other reason that they dont wear out prematurely
and ruin your new motor.
Flat tappet can work out,Bt in my eyes not worth the risk.

Plus the rollers have better and more aggresive profiles

 

[turbo1962]

Who has the best deals on the Roller? Do i need roller rockers?

 

[blown okie]

roller rockers aren't necessary, but are much better than the stockers. the more aggressive profile of a roller may cause alot lot of stress on an already cheesey, & weak design.

 

[corymc]

roller

 

[Hot Air]

No question...roller cam. why use 15-20 year old technology (flat tappet) when you can get the best and you will not have no worry if the cam will survive break-in! BTW, way less friction with roller! Call Jack Cotton, he will fix you up!
Conrad

 

[Rodney87GN]

Yep, roller for sure. Only downside...cost. So start saving up, but you won't regret it! Cottons, Full Throttle, Weber, DLS all have roller cam kits.

 

[79TurboCutlass]

Roller

 

[mazdatech78]

Go roller, im one of those guys that had a Comp Cams flat-tappet not survive break-in. As for roller rockers, im not running them but if you run the stock style shaft set up, at least get the hardened shafts. That and make sure you measure your preload correctly so you wont run into any problems.

James

 

[Russ Merritt]

Going to a roller cam is your best choice by far. Like the rest have said, just for piece of mind should be enough to convince you.

If you do go roller, you'll have to have the exhaust guides machined anything close to or over .500 lift and if your running stock exhaust valves, it has a step built in that will tear up the valve seal if you have them installed on that side. Stock heads didn't have seals on the exhaust from the factory.

 

[boostingbuick]

ROLLER!!! I lost two engines from flat tappets. Not worth it. Sure it will cost more to buy the roller,but how much to replace the fresh engine after the cam fails?

 

[gossamer]

Go roller The only downside is the initial cost.

 

[gnmaster2004]

A roller cam could save your motor!

 

[Brer Rabbit]

another roller vote

No additives with every oil change. Its a no-brainer if the money is there.

 

[machinegun]

I usually recommend the roller cam on my customers engines. However it does come at a cost.

You will need to setup the cam correctly. this can be a little tough if doing it in the car.

Roller cam is more expensive.

Requires either adjustable push rods or to measure and purchase the correct length push rod.

Roller rockers not required. I have used stockers in plenty of cars with no ill effects at all. However you can upgrade to the heavy duty shafts and shaft supports and use ARP studs to install these. This I usually do.

Hope this helps.

 

[turbo1962]

Looks like Roller is the way to go. Thanks for everyones help !
Need to empty the piggy bank.

 

[TurboKen]

"if your running stock exhaust valves, it has a step built in that will tear up the valve seal if you have them installed on that side. Stock heads didn't have seals on the exhaust from the factory."
Russ Merrit"


I'm not sure what you mean, if you have installed an exhaust seal on a head, it will tear it up? But a stock exhaust valve with no seal will be ok?
just trying to learn

Ken

 

[Russ Merritt]

"if your running stock exhaust valves, it has a step built in that will tear up the valve seal if you have them installed on that side. Stock heads didn't have seals on the exhaust from the factory."
Russ Merrit"


I'm not sure what you mean, if you have installed an exhaust seal on a head, it will tear it up? But a stock exhaust valve with no seal will be ok?
just trying to learn

Ken

The stock exhaust valve guide from the factory had no seal installed. Most people when doing a valve job or porting heads, want seals on both intake and exhaust because of smoking issues. So the guides need to be cut down to 1 to accept a seal and 2 to run more lift (most roller cams are in the nieghborhood or in excess of .500 lift). Once a seal is installed on the exhaust guide and the stock exhaust valve is being used, lift comes into play because of the "step" on the valve. If you had a stock exhaust valve in hand you'd see what I mean. Not sure exactly how much lift (I could check tomorrow) but something in the neighborhood of .460-.470 the "step" will be pushed passed the seal causing either the seal to pop off the guide or the seal to be damaged.

If aftermarket valves (Ferrea or Manley) are used there is no "step" on their valve stems and there is no issue. Basically if your heads are off and your either porting or doing a valve job, cut the guides and replace the exhaust valves and you can run any cam you want without issue. Run stock exhaust valves, and you have things to check........

 

[TurboKen]

I got it now, thank you!

Ken