Turbo cam and rocker opinions

[Blizzard242]

Anyone have any favorites? I was looking at yella terra 1.7s and the intense stage 3 turbo cam. And so with the IS3 it says highly modified cylinder heads are needed.. So would bringing the stock heads to a local machine shop to get ported and polished be enough? I'd love to buy some abbotts but those are expensive as hell.. Eh btw about how much should a shop charge to do the heads?

And besides gaskets, valve springs and a timing chain is there anything else that I SHOULD upgrade while doing rockers and a cam? Like would lighter pushrods be a good idea? Lifters? Are new valves of any use or are stockers fine? I think I know everything I need but I want to make sure cause I've started actually buying parts finally. :banana:

[rdrr96]

Re: Turbo cam and rocker opinions

CAM-903 - INTENSE™ Stage 3 Turbo Cam, duration @ .050": 223є/214є, lobe lifts: .338"/.332", valve lifts with 1.60:1 rocker arms: .541"/.531", lobe separation angle: 116є, intake centerline: 110є (+$50.00)

with a .541"/.531" lift on the stock 1.6 style rockers, thats pretty high lift, with the 1.7's youll effectively increase your lift to around a .575"/.565" lift and slightly longer duration. youll probably have to run something like the comp 130# valvesprings. id recommend mildly ported heads, but then again i didnt design either the head nor the cam, maybe intense strictly designed them to work together. i wouldnt recommend going with lighter pushrods, id recommend going with the tougher hardened ones from comp espescially if you plan on revving the motor fairly high. comp oe-r lifters would probably be a good idea seeing as how your going from .400"(up to 1999)-.412"(00-02)intake/.408"(up to 2001)-.413"(2002)exhaust on your stock cam to what your going to be changing it up to... yeah the extra lift probably calls for the oe-r lifters. not sure of the exact limitations of stock rockers, but im sure upgrading wont hurt anything but your wallet.

when running boost your going to be forcing air into your intake, down your intake runners, into the valves, and when they open, they are getting whatever amount of boost your running, so bigger valves may help a bit but probably not as much as youd think.

but then agian, i dont have a turbo car so... you dont even have to take what i said into consideration. but thats my .02

honestly, i personally would like to see a set up with their stage 2 cam, stock heads that have been mildly ported, not heavily ported. run with the comp 130's the proper retainers and keepers with the upgraded push rods and lifters running a nice intercooler

[Blizzard242]

Re: Turbo cam and rocker opinions

Yeah I was thinking about going with the stage 2 cam originally so i wouldn't have to worry about the heads just yet and just have fun with it this season. Especially since this will be my second year racing and the first year modifying anything internal. It could be a really good idea just workin my way up and figuring out performance differences so I get a real good grasp on what all these numbers mean. And maybe save up for some abbott heads :)

So why would you recommend the 130s over the 105s? Also I haven't looked into lifters at all yet. I'm either imagining it or I've always heard that stock lifters are fine when upgrading the valve train on this engine. Btw its a 98.

[rdrr96]

Re: Turbo cam and rocker opinions

well i guess in all reality my head was still thinking the stage 3 cam with the 1.7 RR's, so youd be up closer to a .600 lift, and itd give you that much more cushion on the "limit" of the valvesprings, with the stage 2 cam and the 1.6's id go ahead and go with the 105's actually.

im taking my time on my build and all this precautionary garb im spewing is due to that. i dont want mine to break, atleast not yet. i want to get it done and make enough passes to feel that the mods were satisfactory and that my driving got the best out of them, THEN i want it to break. just before next winter, so i can go through this all again!

[Blizzard242]

Re: Turbo cam and rocker opinions

Well since it's not a daily driver and mainly for racing 130s wouldn't hurt anything right? I read all this stuff a long time ago when I started this obsession its just that I can't remember the specifics that well anymore.. ugh I should take notes.

[rdrr96]

Re: Turbo cam and rocker opinions

i think with the 130's its recommended to remove the sprocket deal from your balance shaft. and i think the timing chain tensioner thing will have more wear and tear, also with the 130's i think your supposed to use the double roller timing chain to delete the need for the timing chain tensioner.

notes are always good. but thats what this sites for! you pop up to the general tech section and go to the stickie thats v6 modification guide or whatever and they have a bunch of people that are selling parts for our cars! its awesome. so i guess in a way, i use this site as a giant note pad! (admin's please dont hate me for that last comment) because in all realiyt this site is a great place to find the information you need to get stuff down for our cars!

[Blizzard242]

Re: Turbo cam and rocker opinions

I'm gettin a double roller anyways.. and I have no idea what the sprocket deal on my balance shaft is yet. I'll understand when I get into it I suppose. Doing this year with an stage 2 cam won't bother me a bit. Hey I can even run personal comparison numbers.

Oh btw, whats the max lift height before I start runnin into trouble?

[techsan23]

Re: Turbo cam and rocker opinions

if your not changing rockers; you probably wont have any prob w/ valve clearance. when you start changing rocker ratio, or machine your heads and/or block you need to measure pushrod length and order new ones accordingly.

its also a good idea to get the valve guides cut down for high lift when you get there.

the lifters are roller type. if you have high miles on your car i would replace. sucks they are so expensive; i bought a set 2 months ago w/ cam.