Questions about 3400 block/3500 top end build

[pacho]

I have bad piston rings in cylinder 1 of my 2002 Oldsmobile Alero 3400 so it's time for an overhaul (115,000 miles on the clock).

What I have to give you an idea of what I'm working with:

CAI
TCE 65mm throttle body
3400 Upper plenum competition ported w/65mm opening
3500 Lower plenum competition
3500 cylinder heads STOCK but have been milled .010"
TOG Headers with full 2.5" exhaust
36# Injectors from Milzy
PCM tune by Milzy Motorsports to account for the 36# injectors and 180* Thermostat plus the other intake/exhaust mods.

Since I'm ripping apart the engine I will do everything at one time, this is the list I'm looking to buy right now:

1. NA Strip Performance Cam (3314/3312, 276/264, 224/212, .536/.520)
2. Comp Cams 26986 Valve Springs (I will use stock 3500 valves, stock seats, stock seals, stock retainers, stock keepers, and stock 8mm rocker arms)
3. Custom Length Pushrods
4. 94-99 GM Timing Chain Set w/Guide
5. Forged 3400 Pistons .020 overbore size (Compression is a question below) with rings
6. Cometic 3500 Head Gasket standard size (.060")

Questions: (if you made it this far reading thanks)

1. I want to double check that I can use STOCK 3500 heads with this cam.
2. Should I opt for hardened custom length pushrods with this setup, and why?
3. Will TCE LS Lifter springs make a difference for me?
4. This strip cam is recommended for a 10.5-11 compression and compatible with 9.5-11 it says in description. My piston options are 10.5 or 11.5 so which should I opt for and what are the disadvantages if any of using higher compression pistons in my setup (11.5 disadvantages vs. 10.5). I've been running 93 octane since Milzy's tune 3 years ago.

Appreciate all responses.

[bob442]

exicuted well, but i have no idea

[Rootie524]

i can sorta help you out. with a cam you need stiffer valve springs and should definitely get the tce lifter springs. 1) it gives you a reason to rip apart your lifters and clean/prep them for your new build and 2) they are stronger to support your raise in lift.

also i'd just go with the 10.5 compression becasue the higher compression with certain PCM tunes will mean you need to run a ridiculous octane gas in order to run efficiently. thats just my personal opinion but thats up to you.

[IsaacHayes]

A cam will help bleed off compression, 93 will let you run 11.5:1 probably but 10:5 will be safe and means you can probalby run lower ocatne if you had to (around here 91 is the highest). You're not goign to gain a TON by going to 11.5 over 10.5. Mine is 11.5 but that's because it has camaro pistons not custom. I've yet to get the motor in the car so who knows how well it will run with 91 around here but I'll tune it as best I can. You don't need hardened pushrods if you are running roller rockers. It's only the older ball-pivot that have metal guides so those need hardened as it's metal rubbing on metal.

Stock heads will work with a cam just fine.

[AaronGTR]

Yeah, if you are using adjustable rockers then you would need heat treated "hardened" pushrods. Since you are using stock rockers you won't need them. Also most if not all places that make custom length pushrods, the minimum wall thickness of the rods they use is thicker than stock, so they will be stiffer and stronger than your stock ones anyway. I know for a fact this is the case with Smith Brothers where I've gotten all my custom push rods at.

For the rest... I see no reason why you couldn't use stock 3500 heads with that cam, but I'm not really familiar with that profile so take that as you will. Personally I'd rather port the heads for better flow and go with a less aggressive cam than use stock heads and an aggressive cam. Haven't tried the LS lifter springs myself so I'm not sure just what kind of difference they make. As for compression, I'd stick with 10.5:1 myself. 11.5 is kinda high if you want a dependable motor with good street manors. And the power difference won't be that great with pump gas and the reduced timing you'll have to run. You'd have to use 100+ octane to really get the most out of it. You can run slightly lower compression and more timing instead. I would consider ditching the head bolts for studs though to keep clamping force even and lower the risk of blowing a head gasket. Especially since you'll be using aftermarket head gaskets, you should make good and sure they are sealed properly IMO.

[pacho]

good advice rootie isaac and aaron. i will go with the TCE lifter springs when i do my build, I'll stick with the 10.5 pistons and I'll wait to have my heads ported before i put in a cam, arp head stud advice taken as well. performance wise the alero is fast atm, but i can't wait to get ported heads and a cam to see what it can really do.

[MY91GT(Z)]

hey isaac you want to sell that motor i have a car that is ready for it and a stg4 clutch on the way ~

[Z26-T]

I'd have to agree with 10.5-1 pistons. You can use 11.5-1 with what Issac said, but i'm a fan of lower compression for a driver, especially if you get a bad batch of fuel. If you put in 93 and it ends up being closer to 85 could kinda suck...

[IsaacHayes]

Shane, WTF, where did you get that Z from? I almost thought it was heavywoodys from the mods but his is a 95... Not selling the motor, the orange car is getting it next summer. Bought a house and that took up my whole summer working on it and working late at work.

[3400-95-Modified]

I didn't modify my heads and my exhaust lobe runs just fine on it.

The specs are in my sig, and I stated the exhaust lobe since thats larger than any one of yours 240/568

last i checked it was 600+ lift you need head work to clear

Are these mostly Ben's parts? If so you may want to replace that Milzy tune with one of his...