chris308

Ok so it looks like life took a sharp left turn on me and I'll be expecting my first child sometime next year!!
My plans of going for 800whp has been budget cut to 550 or so, I'm glad to be able to get that at this point... only because I already have the parts.

I'm going to slap on the A&A setup I have, maybe add some fuel stuff to be safe and that's about it now. No cam, no huge E85 fuel system, no new short block... boy I had dreams!!
However I do have a set of 317's sitting around I could use to swap out my stock 853s?? (99LS1)
If I did this I would have to invest in new parts like studs, gaskets, and trunion kits etc correct?

Would this be worth it? Any hp gain to be had? Pros/cons
Other info - i'll be going straight to a 3.4 pulley instead of the 3.8 or 3.6 that usually comes with a basic kit.

Thanks for any help, comments welcome as well.

MatsA

Turpid porpoise

Absolutely no reason to change the heads if you are capping yourself at 550whp. Just slap on the A&A kit and enjoy. I would recommend upgrading the trunions while you are putting in the work, you don't want the stocks ones to come apart and fill your motor.

stevieturbo

For that 550 goal, just leave the heads alone. Value for money and work involved it would be very hard to justify. Valve springs might be worth a shout though.

tabbruzz

I am in the middle of an A&A build as well with a 3.8 pully. I hope to get close to 500hp. I just have a stock engine as well. You should swap the alternator bracket if you don't have the 2003 updated one. Swapping the plastic power steering pully too while you are at it. A c6 aluminum one is one like 15 bucks...my build wont be done until the spring so if you finish your please post the results

neutron82

I agree, just leave them alone for now and if you want more power later then you could swap on the 317s or some 243s... trunnions, springs, and maybe even pushrods would add a little peace of mind and won't cost a ton or be difficult to replace

_zebra

yeah, the 317s flow better, but unless you're planning to really turn the boost up, the compression drop wouldn't be worth it. i made almost 550whp with a stock 853 LS1 and a TVS... if your centri can't do that on 10-11psi, something's wrong. you're on the east coast, so 93's abundant.

chris308

Thanks for the replies guys.

Yea if I can get this done and near the goal without dumping any more dough into it, that would be awesome!
Maybe I can sell them (317s) and get the trunion stuff for the 853's...

tabbruzz

fyi..I went with stock rockers with updated trunions from michigan motorsports..it was under 190 bucks and worth it in my mind...they claim these rockers and trunions can handle 1000hp with no needle bearing issues as they care captured...

Btmhwb

Just hit it with a 150 shot and call it a day 😎

chris308

For some reason Nitrous has always scared me, and besides I already have the SC kit so theres that...

MRc5z

Btmhwb

if i had the SC kit I would be putting it on also!! I am on a budget so nitrous is my power added by default. It definitely can ruin an engine in a hurry, but i dont think it is scary as long as you read, read, read and have a wideband. When i first put the kit on my C5z i was having fuel issues and sprayed it a few times before i put a wideband in and then found out i was in the high 13s for AFR.....stupid stuff like that is how nitrous gets a bad name. thank god i didnt blow it up!

Did you get the blower used? I feel like i have seen some pretty inexpensive used head units lately, but i feel like it will still add up after you get the proper bracket, fuel injectors, tune, fuel pump, and all of the other stuff required.