1994_383_Z28

iTrader: (1)

Okay, so long story short, I think it may be time for a rebuild on my 115k mile LS1. Car was pretty much stock, except for bolt-on's, until about 103k. At that point it got the g5x3 cam, and supporting valvetrain. It made 404rwhp cam only, but I want more. I think it's time for a freshen up, and of course, I want more power.


So I have come up with 4 basic options, and I want opinions. Which one should I go with? Most power, cheapest? Car is mainly a street car. Will never see forced induction/spray, and only occasionally see the drag strip. I really just want a mean street machine.

OPTION 1:

Stock bottom end rebuild ls1
same G5X3 cam
ported 243 heads
LS2 timing chain
ls7 lifters
melling high pressure oil pump
fast 92mm intake
NW 92mm throttle body
36lb injectors
powerbond 25% underdrive pulley


OPTION 2:

TMS Replacement LS1/LS6 shortblock
same G5X3 cam
ported 243 heads
LS2 timing chain
ls7 lifters
melling high pressure oil pump
fast 92mm intake
NW 92mm throttle body
36lb injectors
powerbond 25% underdrive pulley



OPTION 3:
Low miles or rebuilt LQ9/LQ4 shortblock
TSP L92 ported heads
Custom grind cam (Tick, Pat G, Jeremy Formato..??) (similar to g5x3, but optimized for L92 heads)
LS2 timing chain
ls7 lifters
melling high pressure oil pump
L76 intake manifold
NW 92mm throttle body
36lb injectors
powerbond 25% underdrive pulley


OPTION 4:
Low miles or rebuilt LQ9/LQ4 shortblock
ported 243 heads
same g5x3 cam
LS2 timing chain
ls7 lifters
melling high pressure oil pump
FAST 92mm
NW 92mm throttle body
36lb injectors
powerbond 25% underdrive pulley


I know dyno numbers don't mean anything, but I would REALLY like to see over 450RWHP..

Sales@Tick

iTrader: (3)

The 6.0 with L92 heads would easily make 450rwhp.

With the right port work so can the 243 heads and 347 c.i. engine.

RezinTexas

i would avoid the NW throttle body. Get the FAST 92 unit instead.

dr_whigham

iTrader: (49)

Any data to justify that? I ran a Nick Williams and it was awesome. Never even had to adjust the thing. At all.
What's your reasoning behind that?

Anyway, option 2, but get 42# injectors. You'll be REALLY close if not at 100% IDC on the 36's if you're shooting for 450+

Sell your stock shortblock and you shouldn't be too bad out of pocket.

Rise of the Phoenix

iTrader: (27)

Option 3 is what I'd go with. Square port heads with a custom cam will easily get you there.

1994_383_Z28

iTrader: (1)

I figured either route would make my power goals. I'm just having a hard time deciding if having a higher displacement motor is worth the weight gains of the iron block. My car has minor weight reduction, currently weighing 3480lbs without me in it, and I don't know if I want to mess with that.


Really? That surprises me a lot. I have no hands on experience with either, but I was reading that the FAST throttle bodies are more difficult to tune.

Thanks for the advice on the injectors. Believe it or not, my current setup made 404/382 on stock injectors. Not that it's desirable to have stock injectors.

And I'm going to have to sell the old setup. Being a broke college student sure makes the car game a challenge.

Definitely what I'm leaning towards. My biggest issue is going to be the added weight. I know, I probably won't notice it at all.

Maybe I can find a used tubular k-member in the classifieds to help offset the weight.. We'll see..

1994_383_Z28

iTrader: (1)

Okay. So I've been thinking about this all day and all night and I have some new ideas, and a slightly different goal..

I'm thinking I want to go with a new 370ci TMS shortblock.

http://www.thompsonmotorsports.net/p...products_id=13

The only question I have about this is, should I opt for the ARP main studs? I'm not familiar with the benefits of these, and I couldn't find a lot of information on this. I'm not one to cheap out if these are going to make a reliability difference, but this is a budget build..

And now for the new goal.. I'd like to see 475ish rwhp, and at least 430ft lbs of tq. My current setup is no torque monster, in fact it feels pretty slow until above 3500RPM.. With that said, that doesn't really bother me that much, but I'm definitely looking for a little more this time around.

Onto heads.. My current thought is a set of TSP PRC L92 CNC Ported heads.. But I'm no expert, I've just seen some good numbers through using LS3 top ends before. These will come out to be $1900. with springs, so if anyone has an idea for a better set of heads for the same price, or less, I'm open to ideas.

http://www.texas-speed.com/p-1179-pr...ted-heads.aspx

If I go with the L92 heads, I'd probably just use a ported L76 intake manifold, and a 92mm throttle body. If not, MAYBE I would get a FAST intake, but this is a budget build, so it might just be the same old LS6 intake..

As far as what cam, I'm pretty clueless.. If this was another 5.7 build I would know exactly what I want.. But being a 370ci, and possibly using the square port heads, I really don't know.. So with that said I'll probably wait until I decide on a set of heads, and then contact Pat G, or Tick Performance to get a custom grind cam spec'd. But if anyone has any suggestions, I'd appreciate it..

I think I pretty much have the rest of it covered. I'm going to reuse all of the accessories I already have (waterpump, alternator, ps pump, etc), and I just ordered a Powerbond 25% underdrive pulley that I'm going to throw onto the new motor. I'm going to reuse the oilpan, windage tray, and pickup tube. Reuse my old valve covers, coil packs, all of the sensors. Anything I'm missing? What all should I pull off of the old motor before I sell it. I don't want to buy something I already have.

RezinTexas

I've seen where the NW 92 TB doesn't fit properly on FAST and OEM intakes, leaving some of the gasket exposed.

1994_383_Z28

iTrader: (1)

That's good to know. A good buddy of mine runs a FAST 92mm throttle body on a 102mm FAST intake. He traded a NW 102mm throttle body for the FAST 92mm, but only because of the 102mm throttle body being more difficult to tune.. Who knows.. Maybe he dodged a bullet there..

1994_383_Z28

iTrader: (1)

Well.. I've been doing more thinking, and more research.. And I might just be cheaping out here, or maybe I was getting carried away before.. But I was looking on corvette forum at some guys with C6's who did LS3 top ends on LS2's and their builds..

One example is this copy and pasted from a thread on corvette forum.

"From Scoggins - (Edit - These were the prices in 2008 when we did the swap - exactly 4 years ago)

2 - L92 Heads Part # 012582714 $379.90
8 - Offset Rocker Arms for L92 Part # 012569167 - $94.72
8 - Manley 2.165" L92 Intake Valves # MAN11620 - $111.92
8 - Manley 1.590" L92 exhaust valves# MAN11621 - $111.92
2 - Rocker Pedestals for L92 Part # 012600936 - $31.04
1 - ARP Bolt Set Part # ARP1343610 - $98.95
1 - L76 Bare Manifold # 012590124 - $224.75
1 - Patriot Extreme Gold Spring Set - $279.50
1 - GM Crank Seal # 012585673 - $18.36
1 - IWin Heavy Duty Rollermaster Chain #SD3SR602 $42.35

From ByunSpeed
1 - Powerbond Underdrive Pulley, Belt, Bolt Kit - $200

From CompCams
1- Comp Cam 228/232 114+2 LSA - $404.00

Total of $1997.41"

All of the above is what was swapped onto an LS2.. Keep in mind, it's a C6 vette with 4.10 gears, but it dynoed 461/418..

I'm thinking this might be the way I have to go.. Pretty much the difference is going with stock L92 heads instead of ported ones. This is a budget build, and I don't want the car to be down forever. The power that car made was pretty close to my goals, and I could always go with a more aggressive cam to make a little more power..

KCS

iTrader: (20)

I dropped an iron block in my car and I didn't really notice the extra weight. You might if you race it all the time (drag/autox/etc), but in a street car it's really negligible.

The way I justified it is looking at the power to weight ratios. If you're making 404hp with a 346ci LS1, you're having to accelerate 8.61lbs/hp. If you hit your goal of 475hp, it gets even better at 7.54lbs/hp after taking into account the 100lbs weight penalty. 475hp is a lot easier to make with 370ci than 346ci and will make better torque too.

Sales@Tick

iTrader: (3)

As much as I love Fast products, we have always had better luck with tuning on the NW TB's. The IAC passage in the Fast just isn't large enough.