Hello,

After reading articles and pricing out parts and services. I have decided it is better for me to turbo my L33 5.3 rather than try to reach my power goal of 500rwhp NA. So now the new questions have come up. I know the right way to build this engine would be to have forged pistons, rods, ext. but I have read about numerous turbo set ups where the engine was left stock with no problems. So I have decided to try my luck by choosing that route for the most part.

This is where I am at so far, the engine is tore down and I have inspected it for any obvious problems and it looks good, however it is pretty dirty. I was told the engine had only 40k miles but it looks like much more than that. I have decided to install new rings and hone each cyl. install LS7 lifters, ARP rod bolts and head bolts, and new fel pro head gaskets. Is there any other upgrades that are strongly recommended by those of you with LS turbo experience? should I replace valve springs? comp cams trunion upgrade? push rods? anything else?

your input is appreciated
thanks

 

Valve springs will be needed for boost. The L33 is one of the best motors to use for boost IMHO. You couldn't probably hit 700whp without the lifters/ARPs and never noticed a problem. The rod bolts are usually suspected as the weak point on Gen 4 rods/pistons, so you may never find the breaking point of the stock bottom end as long as you have a good tune.

 

what valve springs are recommend? can I get away with using LS6 springs?

 

With a stock cam, yes, assuming they are actually 40k miles.

PAC1218 springs seem to be the go-to small cam springs.

 

you could prob get away with ls6 springs depending on what cam you go with and what you plan with it in the future but for the added security and peace of mind a set of brian tooley dual valve springs are very cheap insurance!

 

I plan to just use the stock L33 cam. from what I have read the stock cam works well for FI applications. so if new LS6 springs will work i would probably go with those. but Will I want to get titantium retainers as well? or will it be fine to re-use the stock retainers? and what about the push rods? can the stock push rods handle added spring tension?

 

you have to think of it like this: leave it all stock or fall victim to the modding bug hahaha. You upgrade springs, then you upgrade push rods, then cam etc etc etc. Take a look at some of denmah builds (i think thats his SN) You will get a good feel at what to use etc.

 

Do some digging. I think L33 and LS6 springs are the same. The springs that were in my L33 were identical to the spare LS6 springs I had sitting around if I remember right.

Titanium retainers and pushrods are really only needed for high RPM apps. You don't need to rev to make power with a turbo.

 

interesting ill have to look into that. or just buy PAC's 1218's and not have to worry about it.

The turbo I am planning to use is a turbonetics 7675 @ 10psi will that be a safe boost pressure to run on this engine? I know a lot of 5.3 guys run that or more but most are the lower compression LM7's.

 

With a good tune, the L33 should handle about anything you can throw at it. 10 PSI is laughable. You'll just need to make sure your tune is good and you aren't running junk fuel. 91/93 only, meth/water injection will help.

 

In MN the best we get is 91, Im pretty confidant in the shop that I will have do the tuning (modern automotive performance) so having a good tune shouldn't be a problem. I appreciate all of your help.

 

The best we get in MN is E85!!

Do the valve springs. Its a smart upgrade.

What car is this going in?

 

Dont skimp out, do Brian Tooley springs. Run E85 and dont hesitate to max that turbo out, the motor will take it! (skip the rod bolts)

 

i always do , head bolts, ebay studs, mls head gasket , and springs, and be done with it , ,anything else is extra , like cam, intake, rod bolts, etc . i have lh6 which bout to dyno soon,, it has only the things i listed above .. head bolts, mls , springs .. running comp 7879 turbo .. 15lbs or more .. some builds i have went ahead and put a intake, cam , etc ..

 

already have purchased head gasket (Fel pro, that a problem?), arp head bolts, arp rod bolts, new rod bearings (some had light corrosion and I'm already in there so why not) new rings and of course the LS7 lifters. Looks like i'll be adding PAC 1218's to the list as well. and since I have to upgrade my fuel system anyway, I just might set it up for E85.

Going in a nissan 350z.

are dual springs really needed? i planned to use 1218's?

 

no duals are not needed ,, but they are nice.. i have ran both ..fine either way .. ive wanted to do a 350z ,,sweet .. couple of ls1 350zs that are bad *** on this site. as long as the felpro is a mls, if its not, return it .. get a mls head gasket ..

 

Jegs has GM head gasket set for $33 shipped

 

Fel Pro has a nice MLS gasket, make sure its those.

 

It is fel pro MLS #26190pt, once again thanks for all the help. the engine and turbo will not be going into the car until June unfortunately. but that does give me some time to get all of my parts and make sure everything ready. I will start a build thread when the more exciting work starts.

 

Get some ls9 head gaskets and some head studs. I ran that turbo on my camaro with the l33. It was a nice combo