Hot LT4 or LS1?

[Mr Crackhead]

Well I have fooled around quite a bit with both and have plenty of friends that with Late model Fbodies and I personally love the LT1. Give me a low compression LT1 with a Procharger on it and you have one fun toy to drive. The Raw torque feel of a LT1 is just awesome. The LS1's make great power but to me are not the funnest thing out there to drive. If you are wanting to put down around 550 to the wheels i would do a 355 or 383 LT1 with a LT1 conversion at about 8.3 compression, 42lbs injectors, long tubes, a good tune and drive the wheels off of it IMO.

[67SSDan]

I've been following the this thread https://www.pro-touring.com/forum/sh...ad.php?t=12897 and I guess am having the same thoughts. I had, however, only been looking at local swap meets and of course ebay. I had never been to LS1tech.com before (which I noticed that at least SStrokerAce is on there as well!). As soon as I opened the page I saw one for sale for 2500... which is about half of what I'd been seeing. Not too shabby.

I think I'm going to take WS6's advice and sit down and figure out what I REALLY want. I think I'll do some adding as well and see how much of a difference there is going to be in price. I'm honestly kind of leaning towards the 377, but if I find an LS cheap enough I might just snag it up.

Thanks for the input all!

[SStrokerAce]

I have a LS1 daily driver, and part of me really wishes it was a SBC motor because I can do SO much more with them, but the LS1 is a hell of a nice engine design.

Now look at a car that is setup with SBC/BBC from the facotry like your '67 then I would just stick with the SBC.

The 377 with some 290-300cfm heads and a good intake will be a killer motor. 11:1 compression at the least and a roller cam (hyd is what I would do) and you could easily have 500hp.

Bret

[67SSDan]

Is it easy to run that high of compression (given fuel injection of some nature) in a street / some strip pump gas motor? I know Lingenfelter was squeezing quite a bit more compression out of a pump gas motor (didn't he get 14:1 on some of the engines he did?), but I'm definitely no Lingenfelter... nor do I wish to push the envelop THAT much.

Also, anyone have any thoughts on the Holley Stealth Ram setup? I've seen several engine combos with it making big numbers.. but it seems like they're all blower / turbo motors (i.e. Malitude).

[SStrokerAce]

The HSR is a nice intake if you want to get everything done around 6000rpm. The runner length and cross section do make a ton of TQ.

11:1 on a pump gas motor is mild for me.... then again a LT1 can handle more than a normal SBC. For the most part 11:1 is doable on anything if you pay attention to the details.

Bret

[67SSDan]

Given the street nature of the application, I think 6000 RPM is a reasonable number for powerband... don't you? Do you think for the 377 this would be a good decision, or no? Aiming to the 500HP mark, thinking of a mostly street driven car with a desire for strip / track time on occasion...

[Mr Crackhead]

You are wanting 500 HP NA'ed? if so it will take q very stout LT1 to do so. 450 is a pretty attainable goal. The 500 mark gets on the verge of not being as driver friendly for sure. The 7-4 swap cam will add monster top end power, but th esacrifice down low is a pain for a driver.

[SStrokerAce]

500 at the crank or tires?

500 at the crank is pretty easy in a LT1, at the tires it takes some talent.

I would look at 6500rpm as a max speed, it shouldn't be a problem and it will help you make HP to spin it that high.

Bret

[Mr Crackhead]

Yea 500 at the crack is pretty easy to attain, its that last 50 that gets a little harder. Dont get me wrong they will make it just fine, its just the driveability that becomes the issue, or well the comfort driving.

[slow4dr]

I figured better to bump this old thread than to start a new one.

A friend just called me that that has a complete LT4 & M6 for sale. I may be able to pick it up for a very good price so I am contemplating it very seriously.

My question is does anyone know the weight difference between the LS1 & LT1/4? I was thinking about 50-60 lbs?

[WS6]

No,it's well over 100lbs difference.

[Ricoch3T]

500 at the crank or tires?

500 at the crank is pretty easy in a LT1, at the tires it takes some talent.

I would look at 6500rpm as a max speed, it shouldn't be a problem and it will help you make HP to spin it that high.

Bret

The thing I dont' like with the LT series, at least in the one I own is the stupid distributor. Getting rid of that with something else seems pretty expensive. I've been gathering info on doing something with that but hadn't come to a good conclusion yet.

[slow4dr]

No,it's well over 100lbs difference.

I searched LS1tech and camaroZ28 and found so much conflicting information it made my head spin. Results ranged from 60 lbs to 130 lbs difference.


I think I may just get the engine & tranny, weigh it, & if it's a pig I'll sell it & buy a LSx.

[KsKustoms]

I've seen guys drop over 10k on a LT 383 and the whole time I just want to tell them that they could get 100 more hp for the same price if they just ditch that block that they already have. LS motors are becoming very affordable. What you need to do is look at the whole picture before you start buying more parts. There are tons of guys out there that start buying their parts before the price it all out and end up paying more for a motor that they had to compromise on.

[2Loose]

I also wanted to go with the LS motors but just couldn't come up with the coin. I had an LT1 and T56 out of a wrecked '93 camaro, so decided to stay with that, and go with the 396 setup and a set of Lloyd Elliot LE2 ported heads. Of course, gotta then port the intake, upgrade the injectors and tb, and go with a custom chip (the '93's still used a plug in chip, as well as a speed density system). Long ways to go yet, but am looking at about 450 ftlbs average from 2300 to 6300. This is for a pro tour setup 55 chevy. That's about the limit on power for that tranny. That's enough power for me too, have had more in the past, fun, but don't really need it.
2Loose

[WS6]

I searched LS1tech and camaroZ28 and found so much conflicting information it made my head spin. Results ranged from 60 lbs to 130 lbs difference.


I think I may just get the engine & tranny, weigh it, & if it's a pig I'll sell it & buy a LSx.

150lbs more than an LSx doesn't make it a pig. Unless you are really trying to keep the weight down for racing, don't worry about the weight difference between those two setups. Now, if you were talking BBC versus LSX, that would be a different story.

The potential or lack there of in the LT motors is all in the heads and intake. The block, while being unique, is very similar to a SBC. That means the block is not the limiting factor. Hell, the bottom ends of the one peice rear main SBC is the same as the LTx.

The decision to use an LTx or a LSx should really come down to where you are now, where you want to go, and how much do you want to spend or fabricate in some cases. The LTx motors are very good and can be made to perform very well, even cheaply. It's a tough call, but I wouldn't have a problem with using an LTx in a build. Someone on here is building a TT LTx for their first gen. Should be really sweet and make a hell of a lot of power.

[slow4dr]

150lbs more than an LSx doesn't make it a pig. Unless you are really trying to keep the weight down for racing, don't worry about the weight difference between those two setups. Now, if you were talking BBC versus LSX, that would be a different story.

The potential or lack there of in the LT motors is all in the heads and intake. The block, while being unique, is very similar to a SBC. That means the block is not the limiting factor. Hell, the bottom ends of the one peice rear main SBC is the same as the LTx.

The decision to use an LTx or a LSx should really come down to where you are now, where you want to go, and how much do you want to spend or fabricate in some cases. The LTx motors are very good and can be made to perform very well, even cheaply. It's a tough call, but I wouldn't have a problem with using an LTx in a build. Someone on here is building a TT LTx for their first gen. Should be really sweet and make a hell of a lot of power.

I am on a very strict budget but the goal for the car is to keep it under 2500 lbs. Even an extra 100 lbs will make that goal almost unattainable but having the extra money for other things would be nice.


It appears that I will be getting the complete car for next to nothing so I may just part it out and use the funds towards the LSx.

[KsKustoms]

You can do an LS based motor for as little as about 6k. Start with a good base, good crank rods and pistons. Go with some stock (maybe ported a bit but stock castings) heads that are cheap and a stock intake. Get it all set up in your car. Then as you have the money do a head and cam package. Then do the intake. But the best thing to do is get a good base. There is no choice in my mind between an LT or LS motor. Yes the LT can be cheaper to start, but to get the hp that you want you will end up spending more money. If you want I will help you get the motor together. Forged rotating assembly for a 383 LS motor. Then we just hand port the stock stuff so that we can get enough air to the 383. Later on when you get some money we put some AFR heads and a LSX intake and grind a cam. Let me know how much money you have to work with. I can even help you sell some of the old parts that you have. But I really believe that the LS motors are a much better thing to start with then the LT stuff.

On that note. If you just look at the heads you can see the biggest difference. LT motors are basiclly the same as a head that you put on a 350 from the 60's. LS heads are totally different... to be continued. The gf is here and she has had enough of the forums

[WS6]

I am on a very strict budget but the goal for the car is to keep it under 2500 lbs. Even an extra 100 lbs will make that goal almost unattainable but having the extra money for other things would be nice.


It appears that I will be getting the complete car for next to nothing so I may just part it out and use the funds towards the LSx.

If those are the goals then I would start with an LSx engine. It will put you closer in the weight category for sure. I would simply find a salvage LS1 that still runs and has relatively low milage and do a simply heads/cam job with the upgrades included as well. For instance the early 97-00 cars should have their oil pump upgraded and have an LS6 intake dropped on. 01 Fbodies didn't have the LS6 yet either.

[slow4dr]

You can do an LS based motor for as little as about 6k. Start with a good base, good crank rods and pistons. Go with some stock (maybe ported a bit but stock castings) heads that are cheap and a stock intake. Get it all set up in your car. Then as you have the money do a head and cam package. Then do the intake. But the best thing to do is get a good base. There is no choice in my mind between an LT or LS motor. Yes the LT can be cheaper to start, but to get the hp that you want you will end up spending more money. If you want I will help you get the motor together. Forged rotating assembly for a 383 LS motor. Then we just hand port the stock stuff so that we can get enough air to the 383. Later on when you get some money we put some AFR heads and a LSX intake and grind a cam. Let me know how much money you have to work with. I can even help you sell some of the old parts that you have. But I really believe that the LS motors are a much better thing to start with then the LT stuff.

On that note. If you just look at the heads you can see the biggest difference. LT motors are basiclly the same as a head that you put on a 350 from the 60's. LS heads are totally different... to be continued. The gf is here and she has had enough of the forums

I completely agree that the LSx is a better starting point but for the power I am looking for(400WHP) there are many options available to me. I have never really cared to go mainstream but I can't deny the 3rd gen's capabilities just because I am stubborn. I don't plan on spending more than $5K for the engine & tranny and all the parts to make 400WHP. If it does cost more than that then I will be putting a turbo ecotec in the car because I know I can achieve my power & financial goals with it.