18 replies to this topic

[mr5000]

just wondering whats involved on making an early block accept a roller lifter

[slx 050]

Your best bet is to get the lifter bores trued and bushed....

[myss427]

If your talking V8 nothing, but as above it needs to be in great condition and ´expect to spend over $2000 for your cam, lifters, springs, pushrods etc.

[TerrA LX]

Yeah as above, just a matter of buying the holden specific (crane etc) or buick close match roller lifters http://www.aussiev8....fters-cams.html and roller cam.

Edited by TerrA LX, 01 April 2012 - 07:36 PM.

[mr5000]

hmmm 2 gs shit dont no if the gain would be worth it thats about as much as ive spent on the motor to date

[myss427]

Can make good power with a flat tappet, but you get quite a bit more horsepower with a roller with the same lift and duration. You get what you pay for. Plus you don't have to run them in and they are a lot more reliable being billet steal.

[myss427]

I really dont see any reason to go roller unless you are chasing power but the cost is the thing that turns most people off. A good hydrolic flat tappet cam for a street car can not be beaten. No re-lash adjustment and extra noise of the tappets to worry about. I have always gained on average about 30 to 40 extra horses just changing cams with similar lift and duration, but they always have been strong motors, would not bother with it on mild to medium level motors unless they came with a roller setup from the factory.

[orangeLJ]

Every engine combo is different, so saying it will make 45hp more, just by swapping the cam is a bigstatement and one I would be resonably hesitant to believe to be honest.

In some applications it might be true, but its going to be the exception, rather than the rule

[nzxu1]

Been researching this very subject the last few days myself , l'm replacing the original HZ blocked engine in my L34 ( l use it for light motorsport and don't want to risk blowing it up ) with a 355 stroker and was wondering about putting a roller cam in it . Seems that the biggest problem with fitting a roller to an old holden V8 is the loss of oil pressure from the lifters bleeding out the main lifter feed gallery . Looks like Comp cams has made specific lifters to get around this problem ....perhaps to save the cost of bronze sleeving the galleries ?...........this is only my own assumption here so don't shoot me down too hard if l'm WRONG , anyway here's a website that l found that l thought was very interesting ........comp cams part number for the holden lifters is 881-16 .
http://users.telenet...ers_search.html

[rexy]

The problem you describe apparently is an issue with cam lifts over .550 at the valve using std 1.65 ratio rockers. Instead of using the aftermarket lifters in mine (crane cam) we used the factory lifters which have a design which still covers the oil galleries at valve lifts up to at least .600. Crane dont tell you this when you buy their product and we only found out after it was all fitted and the oil pressure was all over the place. We made them take their lifters back.
The factory stuff has now done an uneventful 40,000k on the crane stick.
The combo of hyd roller with aluminium VN style heads is a much nicer and torquier combo than the old steel VN heads and big solid were.

[EunUCh]

2 areas i think the gain is in using roller over flat is.1.the roller
offers less friction .2. you can get a decent lift where it is needed at around 70 deg atdc
of induction stroke.
Add those 2 together and it has to be better.
Me mate builds engines and wont use anything but roller,and as above regarding lifters
Me mate found that out too with the releif on lifter comming out of lifter bore but
just as well he spotted it before the thing was screwed together and got the correct lifters.
Just out of interist,has anyone ever compared how much difference in torque it takes to
turn over a v8 with roller cam compared to flat tappet?