2450 *75/65 = 2827

 

Stock LT1 is 275HP @ 5000 RPM.
When my LT1 was mostly stock the HP started to fade at around 5000 RPM and continued downhill. Now with the mods I have (see sig) the HP peaks at 5400-5500 RPM and the engine falls on its face at 5900 RPM (see dyno chart). My engine is full bolt-on except for the electric water pump and I am putting 301HP to the wheels.

The LT1 heads air flow and the tiny cam are what limit the top end power. Open the heads and get a cam and the LT1 is right there with the LS1.

The problem I am facing is I will be out of my powerband going through the traps with my 4.10's. I would love to have another 100 to 200 useable RPM but I cant get it without either heads or cam. If I had the 3.73's I would be still in my powerband going through the traps but I would give up a bit of accelaration down low. But I really like my 4.10's and I doubt I will switch. I guess I could shift to fifth but I dont think it would help much. Looking at the chart I hope others will agree with this thinking.

 

Really think hard before you put 4.10's in an auto. If you are going to do any sort of driving at highway/interstate speeds, you will be turning at a high RPM for a long time. Guys always think bigger is better for mods, but that's bitten a lot of guys in the butt later on when they lose the initial fun factor and realize that they have to drive the car like that all the time. (big lumpy cam that isn't streetable, large rear gears...)

...and yes, the LT4 springs are only if you want to stay with the stock cam with 1.6 RR's, or the hotcam, but they work excellent in both applications.

Dan

 

OK..What's this 1.6 and 1.7 rockers stuff? I know they are rocker arms, but what is the difference in the 1.6 vs. 1.7???

 

1.5 / 1.6 / 1.7 is the ratio of the rocker arm. If you have a cam with a physical lift of about .360, then with 1.5 rockers (stock) your total lift at the valve becomes .540, with 1.6 rockers: .576, with 1.7 rockers .612

 

Keep in mind however, the further from stock ratio that you go, the harder it becomes to make a stable vavle train. Setting up a 1.7 on a stock heads/cam car is not too bad. However trying to do it on more modified set ups that will consistantly see over 6000RPM's becomes very tricky. You have to be exact with pushrod length. Use quality studs, and make sure you align the rockers over the center of the valve (center left and right, it will swipe up and down over the valve as the rocker travels from rest ( Base circle of cam) to to fully extended ( Valve fully open, at point of lobe on cam).

If you plan to cam it later, go with 1.6 RR. If you for sure with out doubt will be stock heads and cam, then you could go with 1.7's and help it breath a little better.

If I remember correctly, Bret said a month or two ago, about how tricky it is to make a stable 1.7 valve train on these cars that will be reliable at high RPM's. If you are going to go 1.7, I would suggest talking to someone with more experience with them than I know.

 

I ain't afraid of no gear.

 

just curious as to why you went from LS1 to LT1? not flaming, i would choose the LT1 too!

 

Why?

 

i love it if i really wanted to upgrade id go LS2. this is my second LT1

 

Well, I traded the '98 in on teh '01. Then, like the bonehead I am, I traded that in on an '02 Ford F250 PSD 4 door 4X4. Nice truck, but I immediately missed the power of the SS. Recently I was able to purchase another Camaro, not an LS1, but a cheaper, not quite as fun LT1. But...It does a little to quench my thirst for speed.

 

If you didnt have such ***** gears in the back, that LT1 would quench your thirst a little better. Those gears are HORRIBLE for any LT1 car. Gear will wake that car up.



Honda Hunter: Theres alot of reasons some guys like LT1's better ... My list:

More like traditional SBC
Interchangable rotating assemblies with SBC
Parts are cheaper
Been around longer if you dont do your own work ( you should probably learn, cause these cars can be problematic )
Can get OBD I without a wiring harness/PCM swap (head ache ?)
Easy to tune for
Sounds better
Better Body Styling for the Camaros
Is funner to drive with all the low end grunt.

Now thats not to say I wouldnt be happy with a LS1. Just the reasons I went LT1 over LS1 and will stay that way for some time.

One day though, One day ... There will be a LS1 R/A T/A in my driveway. It will be right next to my 383 Procharged ( Or TT maybe?) BRE cammed, LE headed LT1 though