ArmyDude

I have a project ahead of me to rebuild my current 2002 Z28 into a 5-600HP monster. This is a daily driver of sorts and will stay as stock as possible without turbos. Meaning EFI will stay. Here's what I'm looking at.

ORIGINAL THOUGHTS...
4340 Forged 400 Crank - 3.75" Stroke (383 Stroker)
4340 Forged H beam 5.7" or 6" rods
Hydraulic Roller cam - These specs are off of the crate 376/525HP motor. Not familiar with CAM specs to really play with. Still learning.
Valve Lift (in): 0.525" intake / 0.525" exhaust
Camshaft Duration (@0.050 in): 226° intake / 236° exhaust
Replacing the heads with LS3/LS6 style with 64cc to 68cc chambers.
Might need to swap the LS1 intake with an LS6 intake unless there is something better.

I want the ability in the future to add the LSA supercharger that is on my 2013 ZL1. I read the LS3 style heads are required for that supercharger. Right now I just want to build this on a budget of $4K or less in parts. Any other experts have some advice?

All pump gas. 92 Octane

Options:
1)
Buy new LS1 block from SummitRacing.
TickPerformance Callies LS1 383 Rotating Assembly, 3.905" Bore, -6cc Dish Piston, 4.000" Stroke, 6.125" Rod Length.
Stock LS1 heads.... ported. Not sure the amount.
Hydraulic Roller Cam - 239/242 .624"/.592" 115+3
Fast 102MM intake.

2)
Buy new LS2 block from SummitRacing.
383 Rotating assembly. LS1 specs work?
LS3 heads - Not sure of the porting needs.
Hydraulic Roller Cam - 239/242 .624"/.592" 115+3
Fast 102MM intake.


I want to keep this build under $5K. I will do all the work except the extra porting and honing.

Exidous

iTrader: (11)

If we are talking LS1 here and want the future ability to at a supercharger assuming you mean 500-600bhp it can be done but closer to 500 if it's a street car. 600 is really a min/max perfect N/A motor.

4" crank
Pistons @ 3.903-5"
FAST 102 intake. LS6 is for basic builds or FI.
MAST small bore rectangle port heads (for future charger upgrade)
You will need a bigger cam with more lift
More compression. 11-11.5:1 meaning <64cc chambers unless domed pistons are used while N/A.

As far as superchargers go there are better choices. The Magnuson Heartbeat is bigger in volume and smaller in size.

With the mods below I was just short of 500bhp at 10.8SCR granted this was on 346 cubes. The 383 will help on power a little bit and a ton on torque.

ArmyDude

With that compression, wouldn't I need better than pump gas? I was looking more towards 10.7:1. Being that the crate motor from GM Performance is a LS376/525HP, I figured I could build the same motor, with more HP and a cheaper price than $7500. And as far as the supercharger, I was hoping to get the HP without the supercharger. That may be an option down the road. I don't want to spend the $5K plus for that at the moment.

The specs on the crate motor - LS376/525HP
http://www.crateenginedepot.com/LS37...18240C943.aspx

Exidous

iTrader: (11)

With proper quench 11:1 isn't an issue with premium. The LS7 from the factory runs 11:1.

The crate LS376/525HP version simply changes up the cam vs the 480 version. Look at the cam on the 525. It's not a mass production street cam. 226/236 on a 110 LSA will have a good lope to it.

500 isn't all that hard with a 383 N/A. 600 will need an extreme N/A motor or a pretty tame supercharged motor.

If the weight isn't an issue you would be better off starting with an iron 6.0 or 6.2 block(read really cheap and has rectangle port heads) and just throwing a superchager on it. You'd be at 600bhp easy. At the wheels is a lot more work.

As it has been said many time.

Cheap/Fast/Reliable

Pick two.

ArmyDude

Agreed. Thanks for the input. I just hate getting out of the 580HP ZL1 and then driving the 310HP Z28. Seams the car doesn't get out of it's own way sometimes.

Anyway, Mast heads are a bit pricy. I did find a place that can port the heads to spec at any given need for about $1K with a core. http://www.nightmare-breed.com/night...hange-program/

If they can take my LS1 heads in exchange, I may look at that. Or I can buy LS3 heads and see if a machine shop can port them fairly cheap.

The Fast 102 Intake is reasonably priced. I can assume that the existing fuel rails will work with it, or do I need to purchase the Fast ones?

If I can break 500HP and get close to the 525HP crate, that will suffice for now. I did find the ZR1 LS9 Cam available with some good numbers. http://www.nightmare-breed.com/corve...g-upgrade-kit/

Would that CAM have a good lope and get me closer to the HP I'm looking at?

Exidous

iTrader: (11)

The Fast intake is designed for a stock GM LS2 fuel rail.

The ZR1 cam will have no lope. It has a 122.5 LSA and something crazy like -49* overlap. It's a SUPER mild idle cam designed for positive displacement blowers. It will work just fine N/A but you will probably not reach your 500+bhp with it. Once your blower is on there it will really shine. It is also meant for 1.8 ratio rockers and uses a 3 bolt cam gear. It also has no cam angle provision so you have to run an LS2 three bolt 1X gear and LS2 timing chain cover plus a sensor harness extension.

The LS3 heads aren't a good choice for the small bore (<4") motors. Even a honed 383/347 doesn't have a big enough bore for the LS3 heads. One of two things will happen. The intake valve will actually hit the cylinder wall or it will be so close that the shrouding will be terrible and kill flow. The ONLY square port small bore heads are going to be really expensive. You could build a forged iron block with used factory square port heads for less than a pair of square port small bore heads.

Granted said cheap iron block will not get you 500bhp but once the blower is on there it will be a BEAST.

A 500+hp N/A motor and a motor that can take boost are not the same thing if budget is a concern. Said 500 motor would as the least have to get new pistons and a rebalance if the rotating assembly once boost is added.

My suggestion:
Forged 370 LQ4/9. $3300 straight from TSP
Junkyard L92 Heads <$500
LS9 Cam <$100
LS2 cover, gear, sensor (ebay) $150
Valvetrain stock rockers with trunion, beehive springs, lifters and pushrods $600

Blower $$$$$

The above motor could handle a LOT of power. Well over 600whp.

ArmyDude

Interesting. How about the L92 style like in the crate motor?

"Cylinder Heads (P/N 12629063): Aluminum L92-style port; as cast
with 68cc chambers"

http://www.crateenginedepot.com/LS3-...63-P17504.aspx
Aluminum performance head
• Fits any LS family engine with 4.000" bore or larger
• 2.165" hollow stem intake, and 1.590" solid stem exhaust valves
• .570" max valve lift
• As-cast L92 style intake ports
• D-shaped exhaust ports
• As-cast combustion chambers

Exidous

iTrader: (11)

It still requires a 6.0L or bigger motor. 4"+ bore. You cannot get an LS1/6 to 4" without resleeving the block which is over $2k.

The 383/347 use a 3.903/5" bore which sounds damn close but in engine terms it's really not. At all. A tenth of an inch is just too much.

3.905" is the biggest you can safely go. MAYBE 3.907" but that's the extreme.

You can sell off your running motor to recoupe some of the cost.

ArmyDude

So... need the LS3 block like the crate motor. Ugh... that's another $1500 if I buy it new. Maybe I can get one at a junkyard and re-work it.

Exidous

iTrader: (11)

Iron blocks new are about $900 or less. If you have to have aluminim your cost goes up quite a bit.

ArmyDude

Gotcha. Thanks for the help so far. I'll keep digging. That being said, if I get an LS3 block to support the LS3/L92 heads, will the above spec'd CAM and other parts work? Or in order to get the HP I would like, what CAM should I consider?

Exidous

iTrader: (11)

You should decide if you want N/A or boost. Then have someone spec you a cam for your build.

An N/A cam, turbo cam, procharger cam and PD(positive displacement) cam will all be different.

You can use the LS9 cam in the LS3 block. You will just have to use a LS2 1X gear and different sensor. This assumes you will be using your stock PCM and harness. You will also have to use a box to convert the 58X crank trigger to a 24X. Unless you go with a forged bottom end then you can have a 24X put on it and skip the box.

What year is your Z28?

ArmyDude

I plan to run just "stock" motor. No boost.

2002 Z28

Exidous

iTrader: (11)

Are you okay with about an extra 100lb from an iron block?

You could build a stock bottom end iron block that will meet your goals of over 500bhp. You could also do back to the 383 route but skip the LS9 cam. Get one specced for you. The 383 with a used set of $1K heads and a good cam will net you 450whp relatively easily. Assuming FAST intake and LT headers.

Another option is forge your LS1 with the FACTORY crank, forged rods and pistons. Add a procharger. Leave your cam and heads stock. Keep the motor 346 and add boost.

You will be over 500whp without a problem. Then your clutch will need addressing. I just adds up fast.

Or go even cheaper and get just the procharger kit. Skip the forged motor assuming your LS1 is healthy.

ArmyDude

I prefer to spend the extra few bucks and do the aluminum block. I still want to do the 383 Stroker route and add the LS3/L92 heads. I will also add nice headers and exhaust. Is their a reason that the Fast intake is so much better than any other?

wilkes02SS

to do a LS1/LS6 NA is alot of money to be over 500rwhp. my build is as follows and made 568/556. New cam, and 102mm TB are next in the shute.
Engine:
434 Cubic Inch LS6- Darton Wet Sleeve
Cartek Stage 5 Heads- 265 CC- 2.25 Intake/1.7 exhaust CNC Ported
W/ Ferrea Hollow Stem Steel Intake/ Sodium filled exhaust/ Brand New Springs
Comp Cams- 236/259 & 623/623 in @ 112 LSA
Wiseco 4.155 inch pistons = 11.5:1 Compression
Eagle Crank 4 inch Stroke/ H beam Rods 6.125 inch
2 Gallon A.R.E. 3 Stage Dry Sump- Stainless Lines to everything and A/N Fittings for Everything
Runs on a fixed speed density tune not MAF

Fast 102 intake/ TPIS 90 MM TB
Carbon coupler
Vararam Ram Induction System

Exidous

iTrader: (11)

He's after 500bhp not whp. TONS easier. :-) That is a BADASS setup you have their though. I am wanting to trade my 102mm TB for a smaller one but I don't have DBW.

Again. LS3 heads will NOT go on a LS1/LS6. You are stuck with small bore heads. Best factory casting you can do is a 243 or 862 5.3L truck head. There are a ton of heads you can go with. LS3 or any similar head will not work. Check out Texas Speed for an idea. You can also send your 241 heads to AI to be ported.

You have stock manifolds for which the LS6 is best for a cathedral port head. BBK makes an aluminum intake which is bleh at best. FAST makes the best stock style intake by far. Then there are the Vic Jr type but those require hood clerance and are usually for high RPM badass motors. 6800+RPM.

Any of the above listed are better than your LS1 intake. The FAST being the best stock style.

ArmyDude

Thanks. I've since learned that I will definitely need to go with at least an LS3 block. Considering the crate motor is set at 525HP, I figure a few tweeks with the crankshaft and cam should help get a little better. That's what I'm working towards anyway. I'm not sure that the 525HP is rwhp or not, but it's still within my range that I'm attempting.

ArmyDude

Since your suggestion, and my need to have at least an LS3/L92 style head for future LSA supercharger, I'm going to get an LS3 block. I may just get a junkyard motor and tear it down / rework it.

wilkes02SS

500bhp is TONS easier. my 02SS made 456/443 with big H/C/I exhaust and the normal little stuff. It's quite easy to be over 500bhp NA in those cars. Just not cheap, at all.
And Fast Is your best option in my opinion I run them on both my cars and won't look back . Send them to vengeance to be ported and polished as well.