You may be better off selling the 243's and getting some of the low compression heads since you're boosting anyway. You can actually make money on the deal since the 243's are worth double the price you'll pay for the unloved heads.

 

I currently only have the stock 241's on my ls1 was just thinking of going to 243 in the future. I'm on E85 so 10 to 1 or a little over should be fine with 15 psi.

 

Find a gen 4 short block and add a cam and valve train of your choice. 700whp is fine on those. If you trash it build another for $400. Takes ALOT of blown up $400 motors to equal a built motor.

 

 

LPE makes the 58 to 24x converter box. Have a buddy running one with 12k miles on his DD and no issues. We tapped the bosses on the side of the block for the GEN 3 knock sensors. Think we also tapped a boss for an alternator bolt. That and the cam/valvetrain is about it. I'd do the oil pump while you have it at the shortblock level. There's tons of info on here and it's pretty straightforward. Gen 4 stuff is beastly from the factory. For 15psi I wouldn't even gap the rings or anything, especially with the centrifugal since the power is linear. He picked up his shortblock for something like $300 bucks. Stock heads, did the cam and valvetrain and gaskets etc. Been running ever since. You seem to be getting the hang of tuning so just keep it safe and itll live a long time.

 

 

Why did someone say that GM spent a S load developing these motors? And that no one can put one together the same? So no one but GM can build an LS motor?

Interesting.

 

Above 600w is where people start to get sketchy about the regular LS1. E85 definitely helps keep it alive. Gen 4 and I wouldn't blink at 700whp.

 

Sounds like something 8.Lug would say. Oh wait. He DID.

 

 

It's MORE discouraging to see people trying to talk others into dumping thousands of dollars into there cars when their goals do not require doing so.

 

 

 

half the internet says so....the other half says stock motors are 8 second cars and any mods outside of boltons are worthless trash

 

I'm going to build and staff a foundry, an entire engineering department, and a manufacturing facility. Because that is apparently the RIGHT way to put together a short block. In fact, it might be the only way.

 

I'm no expert, but years of dreaming about a procharger have led me down some lengthy internet paths. It's frustrating to see people being called stupid for putting quality parts into a FI build.

As for the comment somewhere above where someone said junkyard motors are $400 so just keep putting those in until they blow up and you'll be money ahead --- who in the F wants to keep swapping motors? And what about when it blows up? I have zero interest in chancing windowing a block and spraying oil all over the track or road while on drag radials going over 100mph. Nah, I'm good. And when those $400 motors blow up, they arent going to blow up on a lift in your garage. They could blow a mile from your house, they could blow at a track that takes two hours to drive too, they can blow up halfway across the country. Then what? It's just a stupid statement. I want to drive my car, not spend all of my free time fixing ****.

Correct me if I'm wrong but don't LS1's tend to start lifting heads easier than others? I've heard that's more of a weakness than the shortblock, if tuned properly obviously. But that info comes from the internet so who knows. I have seen a video of it happen on a dyno. Pretty interesting.

 

 

Have you boosted an Fbody or you just read the internet???? I'm not speaking in the hypothetical world....this is IRL stuff that I do. My 1st boosted setup was a turbo 383 with forged everything. That was before I knew better. For the OP's goals, he does NOT need a forged shortblock because a stock Gen 4 motor WILL handle 700whp. I was simply stating that worst case, IF something were to go wrong, from a bad tune or bad gas, stuck injector, etc. etc., he's out $400 bucks, not $4000. Nobody is saying throw in a crap motor because its $400 and when it blows up, so what, put in another. I'm saying based on his modest goals, he doesnt NEED a forged motor to have a reliable setup.

Friends running a stock Gen 3 shortblock and hit 19 psi on the street on a 78mm turbo on 93 octane only no meth. He's got 12k miles and counting on it as its his daily driver. FWIW, YMMV.

 

That's how I've always done it. In many cases I ran door to door with my buddies with their built engines with my stock ****. I did it out of budget constraints, but it was really impressive seeing what a stock motor will take. I was boosting and putting nitrous on LS vtec motors back in the day and running them to 8100 rpm all day every damn day when people said it couldn't be done.

Agreed and normally would agree with you ddnspider but OP specifically started this thread because he WANTS to build his own motor. That is his main objective.