which would be better a 400 bow tie block (434 later? ) or a LS1 6 speed. I've seen the 400 on sale for $1500 at times. I can get a LS1 with 6-speed for a bout $5k. I guess wiring would be the biggest hassel. or I could get a 400 and put a single plane EFI intake on it. which would be better? power? MPG? longevity?

thanks

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-Tas
'89 Formula WS-6
[soon to be Torch Red with black hood and headlights =) ]

305, TBI, auto, 14x3 chrome flat based open element with K&N, Milodon 160* thermo, functional Formula hood, cross-flow Flowmaster, '99z28 rear pipes and tips....

Super GRK_Taz World
EFI & Intake Options
AOL IM: superGRtaz | ICQ 82881207

 

oooooooooooooo, LS1 6 speed with a nice hole in the hood for it. Better mpg too.

 

This confusing! But any way i would go with the 400sb simply for the fact that for the extra 3500 bucks you save you could do alot to that engine, not to mention an easier swap. The LS1 is much smaller physically, and lighter but I would definitly go 400

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1991 Z28 500hp383 TCI 700R4

 

sorry for the confusiton. the $1500 is a bare raceing block. no nothing else. no heads, no crank, no cam... just a fully machined 400 block. The LS1 however would be complete from radiator to rear end for $5k

 

I'd go LS1, Tas. Easy, high hp, looks nice, will ALWAYS start first tryand CA emmisions friendly, which you and I have to deal with. Building a 400 like that is gonna cost WAY more too, after you get into it.

 

Keep in mind that the LS1 will need all kinds of fabrication work to get it to fit in a thirdgen. The oil pan won't clear the cross member, and it uses totally different motor mouts for example...

 

Still would go with the LS1 just for the fact it's an LS1. $5K for radiator to rear end, I don't think anybody could say that isn't a good deal. A 400 block is nice if you plan on making running the car as a trailor queen. If you want to drive and cruise with it I'm all for the LS1. Strip out everything of the thirdgen and learn how to weld and fabricate. What's the big problem? I've seen the LT1 swaps but an LS1 would just be too cool. I bet the front of the car is going to sit up high because of the weight. To bring the front down you'll either need lower springs or a friend on the hood. What is so cool about having a 400 under the hood? Yes no replacement for displacement but power isn't everything, it's the weight to power ratio. I had trouble choosing the 350ho engine for my engine swap because of the non roller cam, kind of a downgrade. The LS1 is going to cost more to upgrade no doubt but you said it already comes with everything. You have at least 320hp and upgrades like the LS6 intake are already for sale. I don't think I could turn down an LS1 for a 400 if I had the money. Daily driver:LS1, Drag Only:400. Also have to think about the cooling system on the 400 in a thirdgen. We don't exactly have the large truck sized surface area so think about that when you're sitting in traffic.

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, Jon (91 RS too many mods to list)
Dale Earnhart, you have done so much, you will be missed.

 

Andy why do you say an LS1 wouldn't fit? they fit in 4thgens, 4thgens have LT1s too, LT1s fit in thirdgens so why wouldn't an LS1?
And the 400 would be a driver too, I'd put holley single plane EFI on it.

 

Tas, I'm not the same Andy, but I can help. I haven't seen any LS1 swaps yet but, there is inevitably alot of fab work. The oil pan is different, the motor mounts are in a different place. There would be alot of trial and error work in it. SOUNDS FUN THOUGH, do get me wrong!!! I mean small blocks came in second gen cars, but when Hotckis suspension did there LS1 swap, they had to notch out the cross member among other hurdles. Also, I saw one guys sight, who had a Monte Carlo SS (My previos car. He was swapping in an LS1 and was having to box in the front crossmember to clear the oil pan. He tried using a pan from a truck, but it wouldn't go. I think he was going to have the pan machined to.
Anyway, there is alot of work here, but WELL worth the effort! GO with the LS1, you'll be alot happier with the drivability.

If you starting from a bare machined 400 block, you must be cosidering aluminum heads, crank rods, pistons, timing chain, bolts. All high end parts too, I know I wouldn't want to scrimp.
I would sit down and do a price list of what you'll need. I think you'll be supprised how much your going to spend.
The LS1 is the way!