2004silvy

iTrader: (2)

Hi there. New to the site and new to the GTO world. Just picked up a 2004 roller for a good deal and would like to build a mild track car for the wife. 5.3l with 4l60e are quite plentiful around my area so will prob go that route. Prob just be a cammed bolt on car for now with the possibility of boost or a small shot of spray later on. Question is.... will the 5.3l and 4l60e combo plug right up to the gto existing wiring? The PO did a very clean removal job and all plugs fuse panels /everything is still intact. Car was previously and auto car. I obviously know it will need retuned. And I am aware of the reluctor wheel difference in the 05+ (if I read right) truck motors. To further the question now much more work is a 6.0 4l80 swap? They are pretty pricey...but still am curious. I don't think we will need that combo for what we are trying to accomplish but I'm not 100% throwing out that combo yet. Any tips or pointers would be greatly appreciated.

BlwnLs1GTO

iTrader: (12)

Depends on your long term goals and which one is most important. Meaning, do you need something mild now and something to build onto later for big power?
If you're able to go with a straight 5.3 with some boost, it's hard to beat it for the money and reliability. Especially if you're still working with stock drivetrain parts. The 4l60e won't cut it for much for the 500WHP unless it's a built unit. But a 400/4l80trans will work well now and later for big power. They're both fairly easy to put in. Especially the 400. You'll be needing some good axles/stubs and DS as well. And they're not cheap, but will be needed at some point.
I'm assuming you're looking for the best bang for buck with your thoughts set on running fast ETs at the track. (Like most of us)

The 5.3 is hard to beat for the money. (Gen 4 preferred) There's so much information here for support, too.

However,
a big bore/stroke 6.0 is a great foundation for both now and later. It will give you a great foundation for a powerful N/A build right now. But again, if you're going to add a power adder to it, you'll be slightly limited as you'll want to install a decent Heads/Cam/compression combo on your N/A motor. But, these parts are expensive and don't always match up well between the two very different setups. Finding the right combo that will work well between the two is key. If you have E85 where you live, you have a bit more forgiveness. (Wish we had it here )

All of these engines drop right in with minor changes to things like the front timing cover, valley cover, Cam extension harness/Knock sensor harness and possibly a hole drilled into the front of the block for your Alternator that's needed for 05+blocks. If you get an engine with a 58 tooth reluctor, you can purchase the conversion box for another cost.

If I were you, I'd look into some of the vendors here and check out there short/long block combo's. They can spec you out a shortblock, cam and heads that will work well for both N/A and Boosted setups in either Gen block you need.

Hope this helps a little.
Good luck.

2004silvy

iTrader: (2)

Thanks for the reply. Mainly was wondering if everything essentially plugged up...and I think you answered that. I've see5.3 l 4l60e combos for sale all the time in my area ..so that's prob the route we are headed. Any problems with oil pans or any other isues I need to look for? Do the Truck 4l60s fit the tranny cross member the same?

Honestly power goals are pretty low. Maybe 400ish whp when we are done. Prob stick with the 4l60 as well...should hold up with what we are trying to do. Should be plenty fast for her. Honestly was thinking about just throwing a decent size cam in it for now, Usual bolt on stuff, decent stall, tune and let her run it. Maybe later add a little boost or spray. I'd like her to get used to it first though.

I was running mid 13s in my silverado last year with a smallish cam...long tubes tune and some DRs on stock stall. I'm sure the silverado outweighs this thing. Going to be putting a yank in the truck shortly with a small shot for this year.

BlwnLs1GTO

iTrader: (12)

I forgot that you don't have anything as far as the OE engine. Sorry bout that.

you'll definitely need the GTO oil pan.

The truck engines and transmissions (2wd) will work fine with everything but I don't think the GTO harness will reach every sensor without some modifications due to the way the Accessories are located on these engines.
The truck intakes are taller, too. You "Might" need an ls1/ls6 intake but hopefully someone will step in and clear that up for you.

And, If you're able to go the 6.0/4l80e route. It's such a great transmission with much more room to grow. You'll need a new but strong Drive shaft built, a specific Flex Plate and transmission cross member for it. Some have modified the M6 cross members by drilling 2 new holes for the 4l80 swap. There's also a few vendors that offer these pre made parts for the swap. And the other GTO Forum has a ton of information regarding this swap.

Check your local craigslist. There's always deals out there on engines and transmissions.

2004silvy

iTrader: (2)

Yep ..just a roller. Only thing missing other than motor and tranny is the drive shaft. So was planning on having a one piece built or buying one. I'm definitely going to look into the 6.0 4l80 swap a bit more before deciding. I was thinking it was a bit more complicated but it seems it really isn't. I was worried more about the harness compatibility more than anything. If it's just a matter off extending some harnesses then that's no biggie.

Cross member wouldn't be an issue either. I'm skilled enough with a welder to accomplish that I'd say. Hardest part of I bought a 6.0 would be resisting the urge to put it in my truck instead...lol.

BTW I'll try to post a couple pics of it either in this thread or in an introduction thread.

2004silvy

iTrader: (2)

So it's official it's going to be getting a 5.3. Picked up a running and driving 2003 silverado yesterday for pretty cheap. Seems pretty healthy and just over 100k. I'll for sure be putting a cam, springs pushrods in it. Also going to put a stall in it as well. Been in contact with a couple places and seems most are recommending somewhere around a 3200. Mainly because it may get some boost or spray in the future.

I was also brainstorming a bit and was wondering if it was possible to run the truck intake? I have one I started shaving off my truck. I've found info that says it won't clear the stock hood but what about a cowl hood? The fiberglass hood on it isn't bad but needs some work. But I'm not a big fan of the style anyways.

I imagine of I kept the stock truck intake I could run the accessories as is as well. Does anyone have any info on this? Mainly worried about it clearing the drain cowl as well.


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Felix C

what head casting number on that 5.3?

2004silvy

iTrader: (2)

706s....those will be taken care of shortly. Lol.

is that the reason for asking? A friend of mine said not all 706s are bad....just ones with a certain symbol or something in the casting. A local ship can get me a set of 243s for about $600.

Felix C

5.3L came stock with 243s beginning in 2006/2007. Some sources indicate 2005. My 243s came off a 5.3L.

2004silvy

iTrader: (2)

I'm kinda confused on where we are going with this? Lol.

I'm going to pull the 706s off and have them checked before /if they go back on. What is the consensus on here on what heads are good and bad?

Felix C

I thought you were asking me why I asked you what casting number. Ported and big valve upgrade 5.3L, 706, were a staple for head options here before 243s became plentiful. Factor in the cost of larger valves on reworking 706s vs. porting 243s. Combustion chamber on 241s too large for consideration.

2004silvy

iTrader: (2)

Ya I was asking. And I gotcha. I think that's actually what happened with my friend. He took some 706s in and found both were cracked. So they actually hooked him up with some 243s for the same price that they were going to build the 706s for. I still think they ported and cleaned them up a bit as well. He was also saying this same shop told him certain 706s were prone to crack while others were good. Don't know how true that is. The way the 706 are casted on mine definitely look different than the cracked 706s he has. Not sure exactly what I'm going to do with them yet. If I buy a set of 243s I'd be more tempted to put them on my truck and switch the 862s (that I know are good) off of it to the gto.

And while I've got a little action going in this thread ...any suggestions as far as cam ? Stall those sorts of things? I've got a pretty good idea on what I want to do but always open to suggestions. Plans for now were long tubes, yank 3200 , TSP 228r, push rods, springs. As well as a bunch of preventive maintenance stuff, oil pump , water pump, timing set. All new gaskets. Corvette servo and prob shift improver kit for the tranny.

I also need a drive shaft any recommendations that isn't going to break the bank?

BlwnLs1GTO

iTrader: (12)

I'm running the Yank 3600. I forget which line of converters. I can tell you that it drives wonderful and could even use a bit more stall for the occasional hard launches.
When I'm just cruising around, you can hardly tell there's that high of a stall in there. It still moves around nicely in the 2k RPM range.

Hinson has some reasonable deals on DS's. They're aluminum and I haven't hear of any vibration issues like there were early on with these AL DS's.

Jonathan Dawson

So I’m putting in a gen 4 5.3 into my 04 gto and I can’t quite figure out to do as far as wiring and yes I do understand the knock sensors or in different location and the cam sensor as well but do I need to buy a lot that allows me to wiring it or is it as simple as cut and play and just extend the wiring and wrapping and would I have to change anything as for as computers. Btw I do have an t56 transmission don’t know if that would change anything as far as wiring to the engine but if I did I would like to know I’m almost finished building the engine and just didn’t not want to go to the trouble of dropping it in and not being able to wiring it up. Please and thank you 🙏

2004silvy

iTrader: (2)

Wiring will be easy. I'd simply buy a adapter harness that is plug and play. There are many out there and even some that will run both. Another thing you need to take into account is the reluctor wheel. Most are gen 4 are 58x but a few we're 24x . The 2004 Gto was 24x and believe the 05/06 is the same. If it has a black crank sensor it's 24x . Gray is 58x. You will need to buy a converter box or swap reluctor wheels. Lingenfelter sells the conversion box. Your tuner will also need to change the knock sensor values now as well.

BTW since I started this thread I'll give an update. Since we got it going my wife has driven the absolute **** out of this Car. With a stock 5.3 with a TSP 228 cam, long tubes 3600 yank. Car runs mid to high 12s all day. She's getting a Maggie mp112 on it now. 😀
Hope this helps. Good luck!

gametech

iTrader: (1)

Building any kind of a track car out of the GTO will be an expensive process. The motor and trans are the easy part.

Jonathan Dawson

okay great thanks you’ve helped me a lot but what If my the gen 4 block i have already has an 24x with the black crank sensor do I still need the conversion box???

2004silvy

iTrader: (2)

Nope.. you are GTG as far as that is concerned! You'll just need to do the other things I stated and then should be ready to go. Good luck!