v6 to lt4 project

**lowend4** · 04-19-2007, 07:36 AM

Hey folks I have a v6 97 Firebird I am converting over to a LT4. Right now I am still at the start up stage, but am looking to makeing this a major project. This is going to be project that is going to take some time, so I have a few questions and just looking for some answers.

1. Can you run Lt1/lt4 heads on any 350 block or does it specifically have to be an lt1 block.

2. Also, since this is a v6 and a daily driver for the time being. I am upgrading the suspention. Would it be any factor if I started putting on the suspension for a v8.

**BlackLT1Z28** · 04-19-2007, 09:32 AM

Sounds like fun if money isn't an issue. But if you're looking for a budget build/swap, you'd be better off selling the firebird and just buying an LT1 or even an LS1. LT4 cars are rare and can cost more than an LS1.

And no, you can't run LT4 heads on an 350, because they were built for reverse-flow cooling. And you can upgrade the suspension now, shouldn't be a problem. But you may also have to look into a new drivetrain, like tranny (if its a T-5) or rear-end.

PS - LT4 conversions aren't really worth it because you can get more gains from other H/C combos for the same price and GM doesn't make the LT4 parts anymore, so they are pricey anyways.

**Street Lethal** · 04-19-2007, 04:40 PM

Originally Posted by lowend4

Hey folks I have a v6 97 Firebird I am converting over to a LT4. Right now I am still at the start up stage, but am looking to makeing this a major project....

Don't bother yourself with an LT4 swap, it's not worth the time, and it's most certainly not worth the money. Find yourself a decent LT1 engine, complete w/harness. Or better yet, a salvaged donor car....

Originally Posted by lowend4

Can you run Lt1/lt4 heads on any 350 block or does it specifically have to be an lt1 block.

Yes you can, but this requires extensive modification to them (the LT1/LT4 cylinder heads). A friend of mine did this for his 3rd Gen project, and after all that welding afterward, it's clearly not worth such trouble (unless you enjoy the welding)....

Originally Posted by lowend4

Also, since this is a v6 and a daily driver for the time being. I am upgrading the suspention. Would it be any factor if I started putting on the suspension for a v8.

Honestly depends on what factor your referring to. All makes benefit from stronger (and lighter) suspensions. If it helps pass the time until the engine swap, it definitely won't hurt your ride any....

**always faster** · 04-21-2007, 02:55 AM

Originally Posted by lowend4

Hey folks I have a v6 97 Firebird I am converting over to a LT4. Right now I am still at the start up stage, but am looking to makeing this a major project. This is going to be project that is going to take some time, so I have a few questions and just looking for some answers.

1. Can you run Lt1/lt4 heads on any 350 block or does it specifically have to be an lt1 block.

2. Also, since this is a v6 and a daily driver for the time being. I am upgrading the suspention. Would it be any factor if I started putting on the suspension for a v8.

If only you could have start you project last year.There was some last Genuine LT4 crate motor(330hp/340tq) available from GM for 3k but youre too late they are no longer available(i bought the last one

)

I would forget the lt4 since they are very rare now and overpriced.

You have two choices:

-Sell the v6 and buy a original lt1 f-body stock or already modify wich are beginning to be very affordable.

or

-If youre v6 is very clean , find a totalled/wreck v8 f-body and swap all the mechanics.

Originally Posted by BlackLT1Z28

PS - LT4 conversions aren't really worth it because you can get more gains from other H/C combos for the same price and GM doesn't make the LT4 parts anymore, so they are pricey anyways.

The LT4 conversion kit(head,cam,rocker,intake) is worthless yes but the only parts that GM doesnt produce for the LT4 anymore is the intake wich is now available from Edelbrock.The heads,spring,valve,timing chain,etc...are still available.

**BlackLT1Z28** · 04-21-2007, 11:59 AM

Golen makes a 383 LT4 crate motor for ~$5K or so. I think they rated it at 440hp. But I still don't think the conversion is the most cost-effective way of going.

**EviLt4** · 04-21-2007, 12:56 PM

A lot of people forget a TRUE LT4 is a 4 bolt main also. But your in luck, you can have it drilled. The intake manifold is the only think I like about the LT4. As far as the heads and cam..... you can have better for less $.

My HONEST opinion is buy a LT1 car. Its going to cost WAY less and you will have your car sooner than later.