To all, I am about to changemy cam from a C35 scat cam to a Berg 319A.... both have the same lift (0.410") but the Scat has 286 degrees of duration and the Berg has 338 degrees

My question.... what effect will this have on the drivability of the engine, I am very happy with the current drivability in the 1776cc and am interested to know about the new cam. Oh new 044 large valve heads - "unported".

Thanks 063bug

[ Edited on 5-6-2006 by 063bug ]

338 deg duration is way too much for the street!!
The berg 319a cam is the same as an Engle FK89, this is a ratio rocker cam suitable for drag racing only, for high compression big capacity engines with big heads and big port work, it will not be nice to drive in a street driven 1776, if you are happy with your old cam, why change?

i hope that's a typo and you mean G.B 309,

the 319 is way too big for a 1776, Hellbugs all out hillclimb beetle used a 319 and pulled 9400 rpm with it not coming on till around 5000.i have seen the heads that produced these rpms and you aint gonna do it with anything less than extensively welded and hand ported jobbies. no good for the street

GB 319 6000-10000rpm, provided the heads are capable of it. Ideally designed for Berg high ratio rockers where lift at the valve can be controlled with various ratios, (see GB 411 rocker arms) and more flow through the heads. All out race cam with more duration and moderate lift to allow excellent tracking of the cam follower. 334 duration, 0.407" lift at cam.

i used a 310 with a 2180 and it was great, with the 1776 i'm building i will stick to a GB309.

sticking to one of these will allow your valve train to live for a sensible amount of miles and time

http://www.geneberg.com/cat.php?cPath=6_166

http://www.geneberg.com/cat.php?name=All%20Cams%20Below%20Require:&cPath=167

do you have ratio rockers? if not i have a new G.B 300 i would sell. this would work for your set up

[ Edited on 4-6-06 by dumone ]

Good advice guys.
Perhaps you could leave the cam alone and do some head work.
Those unported and "un-chambered" 044s flow worse than stock heads.

ok some more information was obvoiusly required.....

the new engine is a 2276 and I was looking at using 1:1.1 rockers, dual dellorto carbs, 044 heads and these durations and lifts were read straight from the catalogue and I have since been told that I have to use a "factor" on them to get the acutal lift and duration.

.... Do you gents have any comments on this? I have been told it will be street drivable with the 1.1 rockers and the unported heads..... and I guess the open ended question what cam/heads would you use to get a drivable 2276 with heaps of torque, but still idles at ~1000rpm and gets HP at around ~2000rpm to 5000rpm.

standard cam and ported t1 heads?

why 044 with no port work?

No port work.... leaving room for improvement in the future and also so that there is some restriction on the engine so the right foot doesn't damage it.... porting is available... should that option be taken???

i'd be looking at getting some ratio rockers and create the lift at the valve rather than using the cam to produce good high lift.

using the cam for the lift means the ramps have to be very steep to get the valves open and shut within a sensible duration, rougher idles, more of a "on/off" cam sensation. it's harder work on everything because it is accelerated and closed at a rate greater than what would happen with the ratio rockers.

try the links i have above for a sensible description of how each cam operates for ratio rockers....

try this one for non ratio rockers....

http://www.geneberg.com/cat.php?name=Camshaft%20only&cPath=2773 

yeah they're links to bergs, but i can only hope to try and do as much research and development as what was/is done there. they're nice descriptions, not just numbers.

again, i found the gb310 great for the street,maybe look at a gb311 in readiness for some serious port work.

above all it's no sense aiming for big revs and lifts if the heads dont flow enough to operate in the range the cam is designed for. which leads us to.....

port work....i just finished mine and the results have Ben Durie well chuffed,they flow wicked. keep in mind it took 60 hours and add that up at shop rates, say $65 an hour......hmmm.the C.N.C machined ones are supposedly very good out of the box and taking on board the cost of hand done ones, are good value. quotes i got here in Aus for porting ranged from $650-----$3000!!!!- heads supplied by me. mind you, there is no substitute for a good headjob, is there!

heres a couple of pics of the difference even a "clean up" of out of the box castings will make.....

before....



after!!!



what goes in must come out too!

before...



and after!!!




more air in, more fuel mixed with it, bigger explosion for each stroke!!!

[ Edited on 5-6-06 by dumone ]

here is what you need to "use" a 319 cam...

MASSIVE welding and porting...




welded and built up spring seats for chevy style springs lifting over .600 at the valve. shim em up tight enough for enough pressure to run in the 5000 to 9500 rpm range. and be prepared to change the broken ones



need to weld the back too to get the inlet ports big enough...



make room to get the spent gases out too!..



race seat grind, relocated the plugs,reshaped chambers, 44 and 39 valves



and some very good 1.45/1 ratio rockers



[ Edited on 5-6-06 by dumone ]

This should help http://www.cal-look.com/tech/building1.shtml  http://www.cal-look.com/tech/building2.shtml  http://www.cal-look.com/tech/fast.shtml  luck dude:thumb

My suggestion after hundreds of hours of research and five minutes of hands on,Scat C-45 or Engle W-120 or Berg GB-300 there all the same with 1.1 rockers.Or with 1.4 ratio rockers Berg GB-309 Engle FK-43 or 44,OR SO IVE HEARD luck dude.

FK-8 with 1.4 rockers is meant to be a great all round street combination with gentle ramps etc like dumone said. This is probably the same cam as in one of dumone's suggestions as berg cams are meant to be modelled on engle or something like that. If you do a bit of porting on your heads it should pull like a 14 y.o. schoolboy and still be really drivable. The heads should match the cam for the best overall setup.

Heaps of people on thesamba told me to go this way but unfortunately my motor buying funds have dried up so it will be a while before I get to try it. But the 1.4 rockers with a suitable cam are meant to be a great way to go as its easier on the whole valve train. A mate of mine has an FK-10 and it comes on with a big shove around 3500rpm but the FK-8 is meant to be on just that bit sooner making it a better 'all round' street cam

before you go running of to the U.S with there exaggerated figures try the man,http://www.tighecams.com.au/, he was born with a cam in one hand and grew up strapped to a lathe ,if he cant tell you exactly what you need to know nobody can:beer:beer:beer

I second that notion to consult Ivan Tighe - he was very helpful when I was doing research for my type IV.

Alan, you'll be able to see how Brad's ghia behaves shortly (hopefully weekend after the long weekend) - he has a FK8 with 1.4:1 ratio rockers in the 2110. Street eliminators with some mild port work (nothing crazy). Although I haven't driven this setup for quite a while, from memory it was very streetable before the engine was torn down for the rebuild.

I bought an Ivan Tighe (Tighe Engineering) grind in 1980 for my 1640 Baja. Cant rememember the specs but torque was right there at 2200rpm which was what I asked for.

Brendan