Thread: Compression Question

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To start I just purchaced an 88 Silverado C-15 truck with no engine or tranny so I'm in the process of building an engine now, so far all I have is a 350 block, bored .030 over, 3.480 stroke stock crank, stock deck height, with 4 valve relief flat top pistons. My question is about the heads I want, I'm going to get a set of world products s/r torquers with 2.02 and 1.6 valves, 170 cc intake runners and was wondering if I should go with the 67 or 76 cc chamber head?
So basically where would my compression be with the 67 or 76 cc head, and if needed what size or thickness of gasket should I run???

When the compression is sorted out what would you recommend for a carb, cam, and intake?? I,m thinking about the edelbrock torker intake with the edelbrock 600-700 performer carb, just not sure on the cam yet, but I don't want one with over 290 duration or .510 lift, I like the lunati cam with 285 duration and .507 lift just not sure about the 108 lsa, also like comps xe 274, and magnum 286. The truck will have a turbo 350 or 400 tranny with around a 3.42 or 3.73 gear ratio, it will be street driven but mostly on the weekends, may hit the 1/4 once every few months. Thanks for Info

Ok I just searched around for a compresion calculator and I came up with about 9.5 to 1 with the 67cc head and a .039 compressed gasket so I will most likely order the 67cc torquers.
Still need help with a good cam, intake, carb though??? Also what size stall should I use for which ever cam is decided on. I'm really leaning towards comp cams magnum 286h with 286 duration and .490 lift on a 110 lsa if that would be a good decision for the combo

D...Sounds good on your c/r...you'll still make plenty of power, and you wont have to worry so much about the grade of gas. What's the duration at .050 on that cam? Based on the lift, it sounds like a good choice as far as specs. Im not a Comp Cams fan at all, they have had many issues lately. If you get a chance, call Lunati Cams tech line, and try and talk with Steve. Tell him what you have and see if he can steer you right. Try for a Lunati/Ultradyne grind, they work really nice....or one of their Vodoo grinds are getting super grades. A solid lifter cam will give you more punch down low than a hydraulic would, if you dont mind the sound of one....I personally love the sound! And I set my valve lash once each season, in the spring. Some will say you have to adjust them all the time, it's not true. Anyway, I would go with an Edelbrock Performer or Performer RPM intake...the torker is old school, and they dont perform as well as the others. Edelbrock carbs are good, it's just a matter of personal preference. I like the Holley's a bit more, but either will work fine. If you're more performance oriented, the Holley will be the choice...I dont know why it seems to go that way, but Holley will be on most 'race' or hi performance cars...They say 'Holley will win the race, but Edelbrock will get you home from the track' ! It's up to you, both good carbs. Your stall should be 500 rpm below your peak torque, but that's mostly for a race program. I wouldnt go much more than 3000 for the street. And save up your money and get a good one. Dont go for a 'no name' brand...like anything else, you get what you pay for. If you get a good converter, even a high stall speed will still be tight for street driving, and you wont get that problem that everyone talks about, like slipping and making heat at low RPMs...the cheaper ones will do this more. I run a 3200 on the street, and have never had a heat issue at all. Sounds like your combo should rock!! John

The duration at .050 is 236*, also tlked to TCI yesterday and they recommended the street fighter converter for the cam, I think the street fighter is about 1500 rpm over stock, although I probably won't be using the tci converter at least I have an estimated stall speed now.
The only cam I'm thinking of using from lunati would be the street master with a 108 lsa, 285 duration and .507 lift but I,m thinking the lsa might be a little too tight for a street truck, although on ryans combo page that cam with the 200 cc world product sportsman heads made 450 horses and 470 ftlbs of torque in a 383 or 400 ci engine, I don't think I'll be making that much power as I'm only building a 355.
I'm not hoping or trying for a super fast engine just a descent one with about 400 horses and 400 ftlbs of torque, don't need anything too radical.

Good on the coverter. Why is that the only Lunati cam you would use? They have much better cams in their line, and quality is much better than most. I run a 108 on the street, it's not bad. You'll for sure have more of a lope and choppy idle, and you will lose a bit of vacuum. If you want to keep it fairly mild, look for around a 230* duration at .050.

There are more lunati cams, I just want one that I know will make plenty of torque, whats the lift and duration of your 108 lsa cam, what size stall are you running? I also already have a vacuum canister to help with vacuum.
What cam would you consider?

Well, it's not an apples to apple comparison. I have a 505 big block. And I'll be the first to admit, I havn't wrenched on a small block in many years. That being said, my cam is 250/256 at .050, and .655/.663 lift. It is a custom grind, and we went with the 108 LSA to build a bit more cyl. pressure. I wanted low to mid range torque, and didnt care much about hi end HP. I run a 3200 stall converter. The reason Im sorta pushing you to Lunati is that the Vodoo series of cams is incredible. They are a very different design, with a quick opening ramp, but it closes a bit easier (than the CompCams XE series) so that they are easier on valve train parts. They also kicked a** in tests against every other cam. I also know the guy who designed them, and consider him a veritable fountain of knowledge, having spoken with him numerous times. That's why I mentioned speaking to Steve...He was this other guy's right hand man for many years, and knows his designs thru and thru. Im sure he could set you up with something that would blow you away. Remember, the smaller durations will give you more torque, and less top end. Bigger cams, just the opposite. If you go with smaller duration, you also have to be concerned with cylinder pressure...they are more prone to detonation, so you really have to know your dynamic compression ratio. There are lots of things to think about...that's why so many guys are disappointed when they just throw parts together. John