bad1968ss

will keep this as short as possible, new registered member and now a former lurker for years. Been a member on the corvette forum for years and know this is the place for the help I need. Bottom line is I am tired of racking my brain over what direction I want to go on a build and some input from others may help. Plan was for a stock ls3 with a mild cam in a c5z, now down to what I got and where it will lead me. I have picked up a few LS3 parts in the pass year for a build, new crate take out ls3 pistons & rings, stock rods, stock crank, 821 heads , ls3 intake-injectors-manifold, new l92 pistons&rings and a 24x reluctor. Plan was to buy a new block and be done with it but now that has changed since I got a used one. This block with a line bore and t/p hone for 4.070 pistons I will have $400 in savings over a new block but added cost in the long run"snowball effect". So now I can sell both sets of stock pistons and go forged pistons n/p. Now that I will have to re-balance might as well sell the crank and rods and just go for a 416 stroker. From the searches I pulled up so far it seems the stock ls3 heads will need to be ported to benefit going from a 376 to a 416, some input needed here? I can also keep the 3.622 crank & rods with a set 4.070 pistons but I am like most who prefer more displacement. With all that said I would like to keep the compression near stock 10:70 to ls7's 11:1. Need some input on pistons using either wisco, mahle, manley and diamond that would get me in the compression range I am looking for depending on the stroke. Kinda a dd and long trips planned for use but a bit more grunt over the ls6 I have in it now.

truckdoug

iTrader: (25)

you need to decided on a horsepower goal first

bad1968ss

04 c5z with LT hi-flow cats with ti, would like to get in a stock c6 z 46x rwhp territory or above. One question would be on the stock ls3 heads on the 416, would it flow enough for the added cubes. Having said that, going with a 416 what can one expect over the 3.622 stroke running the compression I said. I do know a cam will factor in either way I go so more than likely have to get with Geoff to spec a cam.

KW Baraka

iTrader: (7)

If your goal is only 460 to 470 rwhp..........leave the heads alone, get a rotating assembly (and head gasket set) to bring you to about 11:1 static compression ratio, and get a cam in the 228* to 233* intake duration range with no more than a 114* LSA.

You can consult Brian Tooley Racing or Cam Motion (Google them) for 'professional' cam advice and purchase.

You could have the heads ported (Texas Speed will CNC your heads for about $750 to $800, or so) but the stock heads can hit your HP goals in a good build.

KW

CAMMOTION PERF

The stroker is a nice way to go for sure. You will love the additional mid-range torque. Wiseco, Diamond and CP Bullet all make a nice flat top for a 4" stroke LS3. A good flat top should put you in the 11:25:1 to area with an un-milled 68cc LS3 head which should be fine with the right camshaft and premium fuel.

If you plan to run the 24x crank reluctor, you will need a 1x trigger camshaft timing gear, ls3 front cover and a camshaft sensor adapter/harness extension also.

As for the camshaft, we have some great profiles for daily driver strokers where good manners and drivability are desired. Just let me know if I can help.

bad1968ss

Just got off the phone with the machine shop to let them know of the options I have been considering since the clean-up put into a 4.070 bore. So either way I go, I gave them the green light to go ahead and get the block ready. (KW Baraka) He agreed with your reply on leaving the heads alone. They knew before hand I would have been happy with just a stock bottom end so we never talked about a rwhp goal. I told him since I was going with a stroker that I needed to make a decision on what CR to go with. Before I could say another word he recommend around a 10.5:1 and his reasoning why. He was pretty much on par on what I was thinking so I told him we would shoot for 10.5:1 - 10.7:1. I decided to get a Lunati crank and rods so now I need to search for some pistons. Off hand any you know what brand or part number pistons would put in that ball park either by gasket MLS and milling cylinder heads. Cam Motion thanks I will contact you next week on what you think will work for me.

Senna

iTrader: (1)

Wiseco K394X7


4" stroke-6.125" rod 3.070" bore, 10.6 comp. with .051" gasket and 68cc chamber.

I'm using the stock stroke version in my build.

bad1968ss

Thanks I had just came across the same ones, also Manley Platinum Series 592770C-8
4.070" Bore, 6.125" Rods, 4.000" Stroke, 1.115", 10.6:1 with a .042" gasket 70cc heads

pantera_efi

iTrader: (1)

My "bid" = $1850.00 USD, FOB.

My forged 4.00" crankshaft has a Bob Weight of 1850, allowing "drilling only" for this type of engine.

This "assembly" would be balanced with forged rods, forged FT pistons, rings, pins, TW, etc.

The Piston Brand is RaceTec, made by Wayne Brooks, the founder of J.E.

I could just supply pistons, rings, pins, clips.

MY POINT, "Ask about the Crankshaft Bob Weight @ ???? ".
My guess for you needs is 1815-1835.

Lance

bad1968ss

Update I decide not to do a stroker, got a Mahle L92340070F04 PowerPak set Flat Top -4cc. Talking with mahle they said the pistons run .010 out the hole, shop said they took about .003 off the deck. Does my compression calculation look correct.

Senna

iTrader: (1)

It does look correct. But your quench is going to be around .038. That's a little on the tight side. You really need to measure your deck height with piston installed and confirm deck height numbers. A lot less room for error when you get below .040 quench.

Jimbo1367

I thought ideal quench is .035-.040"

Senna

iTrader: (1)

it is, but the closer you get to .035" the more critical accurate measurement is.

bad1968ss

Short block build should be done by next week to get a accurate measurement. Then moving on to next stage to pick out a cam.

Senna

iTrader: (1)

I'm running a https://www.briantooleyracing.com/ls...-bolt-cam.html

My build is very similar to yours with 6.125 H beam rods and Wiseco Pistons.

NAVYBLUE210

Good decision on the stock stroke for your C5Z, I would
Have a little work done on the exhaust of your heads
And have Kip @ Cam Motion spec a LLSR, something
Like 238*/246*, (subtract ~ 6* for hydraulic equivalent)
114*+3*, .620"/.600", 7500+ REDLINE with good
Drive-ability 500+ RWHP is doable paying attention to details
Without overpowering low end torque.
OverSquare is the way to go.
Just food for thought

bad1968ss

Yes we do have a similar build, I decided on mahle 4032 over wiseco 2618 to help eliminate some cold start up piston slap. A few cams I have been looking at are:
Vengeance Kaotik 235/243 .621/.624 113+2
Tick Polluter 233/248 .627/.612 113+5
Night Fury 233/242 .629/.629 113+3
EPS 228/240 .629/.604 113+2
BTR 225/238 .612/.585 113+3

bad1968ss

I was going to get them cnc ported but as everyone knows it's a snowball effect when it comes to wanting more hp. I plan to contact Kip before pull the trigger on a cam. I seen a post or two that they have a similar lobe to EPS they offer. A few reasons I backed off the LS3 stroker, I would want a bigger bore and longer skirt.

NAVYBLUE210

bad 1968ss
believe me I am well aware of the "snowball effect" check out my
Dyno results for evidence LOL. I wasn't suggesting a full CNC Port
merely some hand attention to the exhaust ports to increase
E/I Flow ratio from 60% to 65%+ that would allow +8* exhaust
split Cam, Vs 12-16* making a more torquey & responsive throttle.

bad1968ss

Confirmed pistons are .013 out the hole after build, shop recommended LS9 Multilayer Head Gasket 12622033 .055" compressed thickness. With that said I will have a .042 quench with a added drop in compression having 4cc valve reliefs vs stock. Next step will be to verify head chambers volume and if I want to bump it up by milling the heads.