Ashton233

Hello everyone. I am new to this and am building my first 5.3 turbo. What I have is a lm7 block with 706 heads. I am wanting to get to the 700hp mark and here is what I'm thinking. Arp head studs and rod bolts, ls7 lifters, ls6 cam springs and intake, ls9 head gaskets, and an on3 76mm turbo. Am I on the right track or do I need to change my game plan? Also can I use the heads I have or do I need to find new ones? Like I said I am new to this site and this is my first build. Any help would be greatly appreciated. Thanks.

LS1NOVA

iTrader: (12)

Turbo is pretty small but would do it. Save the money on rod bolts, they're fine. You can get just the regular MLS ls1 head gaskets from Summit to save some bucks too.

schmendog

iTrader: (10)

I'm doing a similar budget build, hopping on the 5.3 turbo bandwagon and all of its glory. Im hoping to see 800-ish WHP with the possibility of pushing it to 900. After reading a lot of 5.3 turbo threads, it seems many people are recommending the S475 (pretty inexpensive at around $700) for a single, or if your doing twins like me, to try to get On3's or CX Racing turbos similar to precision 6262's. I think I'm going to go with the ebay GT35's, I'm no turbo expert by any means, Im just regurgitating info Ive found on other threads.

Blackpanther99

iTrader: (8)

76mm turbos are good on 5.3s as long as the piping is the adequate size. What are you plans as far as drivetrain goes? M6?

Sarg

iTrader: (6)

Just make sure you find the T4 Gt35's on ebay...even then I think you would be better off and make more power for about the same money with a good ole S475 T6 turbo.

schmendog

iTrader: (10)

I wonder how much bigger the S475 housing is than a GT35? My main reason for wanting to do twins is because I haven't seen a large (or even med-large) single fit inside the GTO engine bay. We have little to no room, and the best bet seems to be battery relocation along with a couple other things, to barely squeeze a pair of twins in the original battery and airbox location..

LS5.3stang

iTrader: (4)

s475 is midframe is really large , gt35 is small frame


s475 > http://i217.photobucket.com/albums/c...N/P1010017.jpg


gt35> http://4.bp.blogspot.com/_-vxlkQsFsc...0/S1050051.JPG

Sarg

iTrader: (6)

S480 with about the same size and my 110 lb wife for comparison...she could not hold it up and had to sit down with it:

schmendog

iTrader: (10)

Haha that's awesome.

Ashton233

As far as heads go do you think the stock 706 heads will be ok?

Sarg

iTrader: (6)

Heads will be perfectly fine. Some studs and some valve springs and you should be golden. On mine I went the extra mile and got a $150 valve job and did the trunion and pushrods to go with the valve springs, but that is it.

schmendog

iTrader: (10)

I think your right on this one. Just read through Denham's 2500 build thread and saw his results....even though his is a 6.0 and Im doing a 5.3 like the OP here, the S475 does seem like it would be a great choice. I still have the problem of space for such a big monster so what are your thoughts of running twin T70's or T76's by CX racing on a 5.3? (Sorry to thread jack OP, but hoping this can contribute to you as well).

HRHohio

Wicked69 is having pretty good luck running twin On3 Performance 70mms:
https://ls1tech.com/forums/forced-in...on3-70mms.html

I think the small turbine on these actually helps when running twins. Just my thoughts.

Sarg

iTrader: (6)

Got a good buddy that we are doing twin on3 70s on his 5.3 in his s10.

Big_Shannon

So with twin t70's are guys still running the .96 turbine or smaller for a faster spool? Sorry to hijack thread. I was just curious.

Sarg

iTrader: (6)

.68 ar on the twin 70s going on my buddies 5.3 motor.

schmendog

iTrader: (10)

I love the results people are getting with these inexpensive turbos, and the fact that they work so well with these budget builds. Some guys who know what their talking about (or at least sound like it) said the same about the small turbines.

I read through Wicked's thread the other day and from what hes posted up I didn't get any definitive results with the 5.3 and twin 70's. Seems like he blew his motor on that pass he posted up and went to a 6.0...would have been nice to see a dyno graph.

Awesome. Is there a build thread? I think Im following at least 5 of them right now similar to what were all doing haha. What I would give to see some side by side track times and or dyno graphs comparing the different available CX, On3 etc...turbos on a 5.3!

Sarg

iTrader: (6)

Here is the thread. He has not updated it in a while, but he is about to get back on it now that he has moved up my way and got settled back in.

https://ls1tech.com/forums/conversio...bo-83-s10.html