[CJZ-SS1LE]

Thinking of switching over to L8T 427 short forged short block but wonderin how it would affect the way it felt being heavier.

[6spdhyperblue]

L8T is 130lbs heavier?

How much heavier is the LT4 and heat exchanger?

[CJZ-SS1LE]

The lt4 weighs in at 530+ lbs which is roughly 75 lbs more than the lt1 but with the light weight forged internals and them boring it out the guys at tsp said it weighs roughly 80 lbs more than the lt1. But id be going from a 220 btr cammed lt1 making 570 rwhp fbo to a custom cammed 230/242 645/631 116+4 cammed 427 with 12.5 to 1 cr. When specing the cam i said i wanted good drivability as this is first anforemost a daily driver an want to enjoy driving it. I want to spin to 6800-7000 rpm, an make roughly 630-650 rwhp on motor. This is the cam they said would work, have a nice chop, and still drive well. Plus with the aftermarket heads with the 2.165 in valves would allow them to really breath well by unshrouding the valves. Havent pulled the trigger just yet still on the fence. Was lookin at a 416 as well then there wouldnt be a weight difference to contend with. To be fair i dont track the car just love straight line acceleration. Iron block with the corged internals will be stronger than even a darton sleeved block. An next stage is to add a procharger with low boost 5-7 psi with E85. I was looking into a darton sleeved block does weigh 40 lbs more than none darton sleeved block so regardless seems like adding weight is unavoidable whether adding supercharger, intercooler, and such. But wanna hear if anyone has gone the l8t route and what they thought.

[2018ZL1]

I am running one. Its a 388. Made 940WHP at 17lbs. Car went 9.37 @ 147MPH. I ended up removing a few things when i installed it so the car actually weighs 19lbs less then when the aluminum motor was it.

I am happy with the way it runs! Its not really a street car but i do have tags on it and drive it on the street from time to time!

[CJZ-SS1LE]

So for you there was actually a weight savings cus you removed weight. I will not be doing that, I like my AC and odds and ends this isnt a race car just want a fun powerful daily that i enjoy driving. What makes it not really a street car anymore?

Plus they made the 5th gen Z28 with a 427, so i wanna make a 6th gen Z28. But alas the car is fast and fun now perhaps after all the brain storming an tryin to make a decision ill just leave it haha.

[2018ZL1]

Originally Posted by CJZ-SS1LE

So for you there was actually a weight savings cus you removed weight. I will not be doing that, I like my AC and odds and ends this isnt a race car just want a fun powerful daily that i enjoy driving. What makes it not really a street car anymore?

Plus they made the 5th gen Z28 with a 427, so i wanna make a 6th gen Z28. But alas the car is fast and fun now perhaps after all the brain storming an tryin to make a decision ill just leave it haha.

Correct... I did a 15 inch conversion out back and I removed the exhaust, turn downs with a baffle in them for the street using a Vband clamp so I can easily remove them when I got o the track. My car still has A/C, had to buy a bracket for it to work with the L8T. Also had to drill and tap on one of the brackets. I run One Ethanol in it so its not very good on fuel!

[CJZ-SS1LE]

Still sounds like a fun build i knew bout the bracker for the ac and i was told bout the assessory hole missin so thats fine.

[NicKey]

Adding the extra weight will drop your front end and affect the way it handles on stock springs.

[CJZ-SS1LE]

Well after some thought decided that darton sleeved aluminum 427 was the way to go

[Judy1le]

Originally Posted by CJZ-SS1LE

Well after some thought decided that darton sleeved aluminum 427 was the way to go

I have a Katech 427 in my 1le and documented the build beginning to end in the 1le section. Give it a look. You will love the 427

[Judy1le]

Originally Posted by CJZ-SS1LE

The lt4 weighs in at 530+ lbs which is roughly 75 lbs more than the lt1 but with the light weight forged internals and them boring it out the guys at tsp said it weighs roughly 80 lbs more than the lt1. But id be going from a 220 btr cammed lt1 making 570 rwhp fbo to a custom cammed 230/242 645/631 116+4 cammed 427 with 12.5 to 1 cr. When specing the cam i said i wanted good drivability as this is first anforemost a daily driver an want to enjoy driving it. I want to spin to 6800-7000 rpm, an make roughly 630-650 rwhp on motor. This is the cam they said would work, have a nice chop, and still drive well. Plus with the aftermarket heads with the 2.165 in valves would allow them to really breath well by unshrouding the valves. Havent pulled the trigger just yet still on the fence. Was lookin at a 416 as well then there wouldnt be a weight difference to contend with. To be fair i dont track the car just love straight line acceleration. Iron block with the corged internals will be stronger than even a darton sleeved block. An next stage is to add a procharger with low boost 5-7 psi with E85. I was looking into a darton sleeved block does weigh 40 lbs more than none darton sleeved block so regardless seems like adding weight is unavoidable whether adding supercharger, intercooler, and such. But wanna hear if anyone has gone the l8t route and what they thought.

Katech took my LT1 and bored, sleeved and stroked it to a 427. 12.5 CR. Spins to 7k. I couldnt tell you the cam specs. Make sure you dont over cam. Sounds like you have experience with cams already, but too much cam can make driving it a nightmare, so I/Katech kept my cam mild to keep the car well mannered on the street but also good behavior for track use. Makes gobs of tq down low. Im not an expert or an engine builder but will running a 12.5 CR and running boost work well? Not sure what pistons/ring specs youd be running.

[JP374]

Originally Posted by 2018ZL1

Correct... I did a 15 inch conversion out back and I removed the exhaust, turn downs with a baffle in them for the street using a Vband clamp so I can easily remove them when I got o the track. My car still has A/C, had to buy a bracket for it to work with the L8T. Also had to drill and tap on one of the brackets. I run One Ethanol in it so its not very good on fuel!

What bracket/Alternator did you use with the L8T? Stock lt4/Lt1 setup?

[2018ZL1]

Originally Posted by JP374

What bracket/Alternator did you use with the L8T? Stock lt4/Lt1 setup?

this;

https://latemodelengines.com/all-cat...y-bracket.html

[2018ZL1]

Originally Posted by JP374

What bracket/Alternator did you use with the L8T? Stock lt4/Lt1 setup?

This bracket is for mounting of the A/C Compressor.

The L8T didnt have the holes from the factory.