I just picked up a 2001 Z28 1SC car with a blown motor. Just got the motor tore down last night and the #7 rod was snapped in half. The cylinder wall looks pretty good and just needs a slight clean up on it. The starter got torqued off and broke the mounting point on the block so that would need to be addressed if I decided to use this block.

My plan initially was to buy a junk yard LQ4 with higher mileage and toss some rod bolts in it and let it eat. Since the LS1 block and crank are in pretty good shape I was kicking around the idea of getting some forged rods and pistons for it and running it. Just looking for some opinions on what you all would do.

My plans are a budget build for either motor.

-On3 76mm .96AR turbo
-TU1 Cam
-Dual valve springs
-Truck manifolds
-2.5" Spoolin hotside kit that I am getting from a buddy
-Ebay intercooler
-Tial wastegate
-BOV? not sure which one

This car will see the track a couple times of year and get driven a lot on the street. I don't really have any HP goals but would like it to make north of 550 at the tires.

I know if I forge the LS1 and get all new bearings and clean it up I will have more piece of mind knowing it should take a beating. If I go the LQ4 route I would be nervous on running a higer mileage motor without touching the bottom end. One of the local JY's has a LQ4 from a van with 75k miles on it and they want $950 for it which doesn't seem like too bad of a deal. If for some reason that fell through would it be a terrible idea to look for a 100+k mileage motor and run that?

Am I correct in assuming if I go stock bottom end LQ4 it will be cheaper up front compared to prepping my current block and forging it? If I kept the LS1 I would have to buy truck manifolds and would want some 317's to go on top and the LQ4 would already come with these.

Again, just looking for some opinions.

Thanks for any help and suggestions.

 

It's all up to your budget... The LS1 will cost more to build but there are advantages to having forged components. People have also had great results with JY LQ4/9 builds as well... Alot of people get iron 5.3's now and have success with them.

As far as a BOV i would look into the RPS if on a budget... Rob from modular turbo sells them and they are 100$....

Oh and the heads, If you go with the LS1 and forge it you'll be able to lower the compression via piston dish so you could use you stock ls1 heads for now and get a better head later if you wanted.

 

Thanks for the reply. This will be my first "big" build that I have done.

My budget is not HUGE, however if it takes me a little longer to save up and do things right then that is what I will do. If I did go with an LQ4 now and ran it stock for a year without it blowing, then I would more than likely pull it again next winter and forge it.

Of course the other big ticket items (drivetrain) will need their attention as well.

 

I would part out the ls1 and go with the lq4. 98z28cobrakiller and Maxxmitchell both ran LQ motors and ran bottom 10's on them in stock form. When you build it later you can accomodate the compression the way you want plus you have better selection of internals from different manufacturers. Also, with the 4" bore from the LQ block you have a better selection of heads out there also to run. Most common boost builds using iron blocks are 370 cu in and 408 cu in. 98z28cobrakiller has been 8.98 on his stock crank truck block 370 motor in full weight trim.

Bottom line, I would go with the LQ motor.

 

Any idea what my stock block with the broken starter mount and stock crank would go for?

Do you know what the mileage on their LQ motors was 87silverbullet? What mileage is on some of you other guys' JY LQ4 pullouts?

Thanks.

 

Out of a forged LS1 vs stock high mileage LQ4 I would definitely go with the first option if you can swing the cash. If money is tight then yes get the cheap LQ4, part out the LS1 to recoup some money and hope that the engine holds.

 

I would have to say 6.0. there is more room to grow and future builds for this engine. Also finding someone to weld the cast aluminum ear back on the block and not ruin anything else and be proper would worry me more.

 

^ Good point. Thanks man.

 

B18 Swap. Well, that or a 20B.

 

I currently have an Lq4 in my car and I am building on it. I have every intention of blowing up this engine and then forging it. Before it blows though, I am confident I can easily get 600whp daily driver reliable out of it.

If I were going to forge an engine, I would not do it to the aluminum one over the Iron one.