[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

[LT4Firehawk]

No, the LS1 wasn't tuned, and while I'm sure you can get some improvement on an LS1, I honestly don't think it's going to be 36lb/ft gain on the low end. I was just trying to give a decent comparison of numbers, the LT4 cars came with LT1 ECM tuning, which significantly limited the HP, allowing for a way larger jump with proper tuning than you'll get tuning an LS1. I honestly don't think there's going to be enough difference between properly setup LT4/LS1, and the driver would make a much bigger difference. I personally just like the LT4 better than the LS1 after having owned both. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif) The bigger difference would be that you can run the 93 tranny with the LT4.

[Mojave]

No, the LS1 wasn't tuned, and while I'm sure you can get some improvement on an LS1, I honestly don't think it's going to be 36lb/ft gain on the low end. I was just trying to give a decent comparison of numbers, the LT4 cars came with LT1 ECM tuning, which significantly limited the HP, allowing for a way larger jump with proper tuning than you'll get tuning an LS1. I honestly don't think there's going to be enough difference between properly setup LT4/LS1, and the driver would make a much bigger difference. I personally just like the LT4 better than the LS1 after having owned both. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif) The bigger difference would be that you can run the 93 tranny with the LT4.

I currently own both an LT4 and an LS1, and I wish it was two LS1's. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/biggrin.gif) In the context of ESP it may not be that big of a difference, but LS1 + long tubes + cam = very happy me. On top of that, no opti-spark! That is reason enough to get an LSx!