Keep in mind, when you change heads, get them milled, or change head gaskets, you'll most likely need new pushrods. Adjustable or resized. Lifter preload will change. Or you can go roller rocker$!! ElectraJim
The heads can be milled quite a bit but too much and you willo have to correct the geometry by milling the intake to keep it fitting properly. I suggest milling 30 thousands, any more and you will need to get different pushrods.
I plan to have whoever ports my heads also port a Stage 1 intake for me as well so I guess I could go ahead I have the intake milled for proper geometry. Also I don't mind using different pushrods either. How much would have to be taken off to get 9.5 to 1 comp ratio?
In this thread bellow there is info on how to calculate the comp ratio. http://www.v8buick.com/showthread.php?t=83234 Here are the common ways to change the compratio: 1. milling the heads or block (makes no difference which one you choose because the 350 heads have no quench area) 2. Change to different pistons. The suposed 10.25 pistons for early motors really only yeild about 9.5:1 even in the older low deck blocks and I measured 9.0 using these pistons in a later tall deck 350 (tall deck was really 7.9 comp ratio vs the advertised 8.5). I suggest if your not rtebuilding the bottom end then mill the heads and have intake matched. Downside to this is that the intake will be married to those heads or at least heads that have been milled that amount. Upside is you can up the comp without rebuilding the bottom end If you are rebuilding the bottom then buy the Poston flattop pistons that are rated at 10.25 but will still leave you in the mid to high 9 comp ratio and you can leave the heads/pushrods/intake alone.
I just bought a 290-94h. I wont have any feedack for a while. I am going to wait and rebuild it at the same time.
sean i looked at the desktop dyno stuff posted a bit ago on cams for 350 it looks like most will make the close to the same power in power ranges that are similar of the cams listed on that thread so i was thinking we could use some fresh grinds for n/a and forced air anything in the works? i know desktop dyno isnt always that accurate but how can you really tell but for experiance
Well we are looking at having some solid roller grinds similar to the performance turbo v6 cams that are on the market now. Not sure when we will get into this but to start I'll be using my 398 hp TA-212 cammed engine to findout how that works with the boost. We are gaining more and more connections and things are getting really interesting lately!
I just buoght the comp cam #92-203-4......469 on intake and exh, 268 duration. havent got it installed yet, block goes in mid dec. .030 bottom up rebuild
WOW all those replies before someone even mentioned a Comp. I run a Comp 268 in my 350 and I love it. Very streetable and pulls hard to 5000. Mild lope, enough to let people you have something in the motor. 14-15lb vacuum at idle. I have flowmaster 40s and Once pulled into a cruise next to an El Camino. The 1st thing out of that guy's mouth was "MAN that thing sounds NASTY!" made me smile. I am very happy with my Comp Cam.
I was just about to add that I use the Comp Cam 268 High Energy camshaft. When I first built the motor with my dad, we only went 2 bumps from stock (260 or 262 comp cam, I can't remember which one it is) and it was ok. But when I wore that cam out, we bumped it up to the 268 and it was very noticeable. I didn't want anything radical, and I wanted horsepower and fuel mileage to go up together. I've got over 100,000 miles on my rebuilt and it pulls as hard as the day we put it in. And as previously mentioned, it's got a little lope that talks to bystanders through the flowmasters that makes them want to know whatcha got under the hood. -Josh
I was looking into getting one of the comp cams. Its just a daily driver but I still want some umpf without sacrificing gas mileage. I see in the comp book that they require new springs for the 260 and 268, but not the 252. What do you guys think? Evan
I originaly went with a GS118 it lasted about 1,000 miles so I ordered another GS118 from poston and when I opened the box, they sent me a poor regrind and it and the lifters are sitting on the shelf! I bought a Comp Cams 268H 110 centers and love it!! Works great and sounds awesome. Doug
I had the same questions when selecting a cam. What got me to order not only the cam but the lifters and springs as well is that Comp requires you to use "new lifters and proper valve springs" for their warranty to be honored. That quote is directly from their cam card. Best bet is a Comp K-Kit with new everything. I bought separate and spent more. sighhhh...lesson learned.
Our new engine that we orderd will have the TA_510-455 (455H.576" -255/.576" -265,110") with alu TA STG1 Track eliminator heads, with roller rockers, SP2 intake, full porting, etc etc. Engine is going to be in the 600+ HP range is our goal. Plan is to get our 3800lbs car in the 10.90s ET, Jim Weise is building an TH400trans for it with a 9.5 convertor that has 4500 stall.
Opa, I think you made the same misake I've made in the past - responding with Big Block detail in a Small Block thread. :error: Devon
Interesting that nobody has mentioned (or admitted to using) an Isky cam. I have the Isky 270 for my 340, I got it NIB from a friend for $75. Everything is done, got all the parts and the block is back from the shop, but I must get other things done before I assemble it... Don't want to get ahead of myself. Anyone ever use Isky? 3-2-09 update I've decided not to use this cam and instead went with a cam (TA 284-88) that's better suited for the Buick 340.
Oops, sorry about that! Didn't see it was a smallblock topic. To stay on topic in our now sold 464 engine that was build in 1999-2000 they used a Lunati cam, very agressive lump and idle and not much vacuum for PB to work. http://www.youtube.com/watch?v=Y8-Fon0YVoc&feature=channel_page
