i know people w/ a lt4 are running more HP than me w/ a bigger cam with 350CI of displacement

the reason i still use the LT4 hotcam is to pass smog
my car passes CA smog w/ no problems

my heads outflow a lot of aftermarket pre-ported/polished heads

my old SB Chevy had Airflow research twisted wedge heads w/ 240/225CFM of flow @ .550lift

my head flow 295 intake/290 exhuast cfm @ .600 lift after the CNC porting job done in november (when the engine got re-stroked to 427)
the new valve size is 2.06/1.7 (valves look like they are touching each other, but the machine shop said they will be fine - and i have 3 7000RPM dyno runs, and 6000 miles on them, and had no problems

if anyone has any suggestions on a cam that will still let me pass smog, let me know (dyno shop said they can get me a cam that will hit 700RWHP, but i can not pass smog, and will need a 3800stall)

 

#1:
*we x-rayed block, found out that we can bore to 4.250 inch and still have .25inch of material around cylinders (4bolt blocks have thicker cylinder wall compared to 2-bolt blocks)
*we then bored to 4.25, then we sleeved it w/ a steel sleeve that was bored to 4.12
*we used block filler to fill the area around the cylinders w/ a block filler that x-fers heat at a very high rate
*we machined the filled area to allow coolant to get to the heads
*i got a stroker kit from ebay (4inch stroke, 4.12inch pistons (forged keith black 11.0:1 ratio, rings, bearings, etc)
*we check the crank and pistons, we discovered it was a forged steel nitrate treated crank
*we replaced the factory 4-bolt LT4 caps w/ steel 4-bolt SBC caps made for a heavyduty truck engine (1974 4-bolt 350HP 2ton truck block)
*we put it together, then toke it to the balance shop, they balanced it, and stated my engine (bottom end) would be good upto 1250HP/8500RPM



#2: people who use a CNC machine

 

Screws, staples and a little CA to close the skin?

The 4 large sounds low to me also.

 

Granted...this is a completely built solid roller LS1 motor...but it is stock displacement
http://www.ls1tech.com/forums/showthread.php?t=122193

Over 500 rwhp NA, and no spray.

Wait til spring and you'll see heads/cam cars doing this with some other bolt ons.

 

LS1-- 300 stock
LT1-- 250 stock
LS1+exhaust,intake,tune--325-350hp
LT1+exhuast,intake,tune--270-300hp
LS1 w/ bolt ons and a cam--390-410hp
LT1 w/ bolt ons and a cam--340-360hp
LS1 w/ heads and cam-------435-480hp
LT1 w/ heads and cam-------350-400hp

thats where most of the #'s i have seen.

its all in the combos'

 

I'll wait a few more yrs like 2 when LS1's sell for 7K. Then I'll buy one and shoot for 500rwhp and not have to spend all the money that people now are spending to get those numbers. Just like plasma screens, dvd players, and any other electronic gizmo out there.....they get cheaper over time.

Hurts my heart though us LT1's can't get those kinds of numbers w/out some serious $$ involved.

 

Correct me if I'm wrong here, but I believe Phil is shooting for 500rhwp with a 350 or 355, can't remember the dispalcement. I hope he gets it

 

I believe I heard something about that too, shooting for it with a smaller (350/355) motor.

 

stock for stock.....

LS1 > LT1,

mod for mod.....

LS1 > LT1

There's no nice way to put it. The LS will beat you silly with it's induction. Not only do the heads flow more air... they flow better quality air. No siamesed exhaust valves and no dog-leg intake runners. Even the LS intake is ahead of the LT1/LT4 because it actually has some runner length. That longer runner is going to store more air and the charge is going to have more inertia behind it. All this, not to mention the air is going to be denser... all good for VE.

It's limitation is in the modding.... but they developed a cast aluminum intake to remedy that. That and FAST addressed a few issues to make the polymer intake "better" for those guys staying that route.

Take all this away and you have 8 holes filled with piston, a crankshaft, rods, an aluminum block, and a few other things that are nice but don't necessarily make it that much superior to the LT1. The LT from a shortblock perspective is not so much different than a generation 1 small block. Yes, it has it's own waterpump, a block designed around reverse cool and a few other differences but then so does the LS.

Now consider that a gen1 small block 350 has the potential to make in the neighborhood of 600hp at the crankshaft and in a very streetable configuration... that's ~520rwhp for those of you who think in "rw".
So where's the real difference? How do you correct that besides going to gen1 and making the swap?

There really isn't much sense whining about it. The voodoo is not so voodoo anymore.

Good cylinder head (something competitive), intake manifold and you've leveled the playing field.

-Mindgame

 

And from what's being said in that other thread about Bret's intake manifold, the playing field may be very close to level shortly.

 

Well I make only 351rwhp 337rwtq and 535rwhp 505rwtq on the 150 shot and run the times in the sig with a 3650 raceweight. Dyno numbers do not win the races ET's do. I think the reason behind my dyno numbers being low was the 28x12.5 slicks, 35 spline axles through a heavy 9 in rear, and a th400 with a 4200 stall converter. I'd rather see ET/ mph along with raceweight to compare apples to apples.

Matt

 

Mikey at Rapid Motorsports recently got 502rwhp out of a stock bottom end LS1 in their latest project car. I've seen the car at the track here, that is truly incredible.

I know the LSx is an amazing engine and will make more power than the LTx with similar mods just like everyone else here, it doesnt bother me at all. My stock bottom end, stock head, 'little cam' LT1 makes more power than I ever expected it would, plus mods are much more affordable for it, it sounds much better than almost any LSx I've come accross and it never fails to put a big smile on my face at WOT. I'm sure plenty of LS1 guys will have to jump ship to get on the LS2 bandwagon now, thats great for them if they have the money to do it, more power to them. Right now I'm very happy with what I have.

 

I totally agree with you Greg. My car is paid for and is built alreay now why would I sell it for half what I have in it then buy a LS1 car and spend 10k to get back where I am then sell it next year for half of that then buy a LS2 and start over? Now LS1's make more power stock for stock and usually mod for mod but not usually dollar for dollar. Go price a heads/cam, boltons, setuo for a LS1 and LT1. So what if my LT1 has to have heads/cam to run with a cam only LS1 it's still cheaper for me. Later Clint

 

As someone said earlier.....The LT1 is down by 40-50 HP +/- .
It seems to me that that gap ususaully stays about the same mod for mod.
The LS1 is a different engine all together. GM is will probalbly come out with an engine that will be up 40-50 HP over the LS1 engine in the future if they haven't already done it or started on it.
I don't even want to think about what the HP ratings will be 10 years from now on stock GM vehicals (even Mustangs).
Its all about advancing technology

Tim

 

In the JUly 2004 issue of GM high tech there is a 98 z28 that has 487rwhp /428rwtq with a stock bottom end.
they say that with the accesory belt off they are putting down 491/430.
car has 11:1 cr,LS6 ported heads(cartek),2.02/1.57,LS6 intake ported by Cartek, CompCams hydraulic roller, 224/228 at .050, .570/.570-inch lift, 113 LSA, stock rocker arms, Cartek TB, Grotyohann 1.75 long-tubes, 2.5 X-pipe and dynomax mufflers...

runs 10.69 @ 128 , 3260lbs

9 inch, 4.10 ET Drags, Qa1 shocks