[tjZ28]

I'm under the impression you can legally swap a LS1 and the accompanying T56 into an older ('93-'97) 4th Gen Fbody for ESP. So, assuming that is correct what do you think would be the better combo?

* LT4 built to the limits of ESP rules + the '93 Trans gearing

or

* LS1 built to the limits of ESP rules + '98+ Trans gearing?

Let's assume this is in a '97 Hardtop Z28 built to the full limit of ESP rules also. The car generally would run on a large, fast, smooth, ultra-grippy concrete lot. BUT it would hopefully see Nationals in the next 2-3 years so it'd need to work on smaller, slippery surfaces too.

Running the numbers on 2nd gear only (since that’s where the car will spend at least 90% of it’s AutoX time) the ’93 Trans gearing would give about a 14% increase in RPM vs. the ‘94+. For example, if the ‘94+ gearing would have you at 3,000 RPM the ’93 would have you at 3,420 RPM.

I think it’s safe to say that the LT4 can match the LS1 on torque/hp until maybe 4500 or 5000 RPM. Only losing out a bit right up to ~6200-6300. But can a LS1 make as much torque/hp at 3,000 RPM as a LT4 could at 3,420 RPM?

Thoughts?

-TJ

PS- Yes, my head hurts too.

This post has been edited by tjZ28: Jul 11 2007, 12:53 AM

[Mojave]

The LS1 will be lighter. Less weight on the front is a good thing.

[tjZ28]

The LS1 will be lighter. Less weight on the front is a good thing.

Very true. Does anybody have the weights for a dressed LT1/4 vs. LS1?

Also, if you go w/ an LS1 can you mix 'n match over the years? For example a '00 cam w/ '01 heads? If I'm reading the rules right the answer is "NO" since you have to update/backdate as a "unit." However, if you are using all factory LS1 parts does that still count as a "unit" even though the parts are sourced from a few different years?

Garrrrr, I hate rule books.

-TJ