50kta

im going to use the stock heads BUT Texas speed is going to P&P them. so with me boreing out the 5.3 with stock size heads how much can i bore the block? and do i use head gaskets off something like a 6.0?

knievel

iTrader: (11)

I would guess that you would use gaskets from an LS1
the 5.3

IIRC you can bore the 5.3 block to 3.90ish

NemeSS

iTrader: (127)

.060 over will be fine = 3.84 bore with stock 3.622 stroke =336ci=5.5L

ten5nova

Do you know this for a fact? I have a stock short block 5.3 that I would like to overbore at some point.

NemeSS

iTrader: (127)

yup, ive machined/assembled a few ls. ive even punched out to 3.905 bore or ls1 bore. but would not reccomend it due to the xpense for the machine work, and the minimal gains found. if u need big bore. just pay for a 6.0 and go 4.060 bore. the machining alone for the 5.3< ->5.7 will be more than a conventional .03-.06 ovebore on a 6.0. the 5.3 needs around .115-.120 of material removed plus the final hone and finish.

speed pro makes replacement pistons for the 4.8/5.3 that are hung on stock rods and used with stock crank and are around 400$ with rings.

.060 over 5.3 with 4.8 flat tops will make for high compression 5.5 engine.
build with a 22x-230 cam and some 241 or 243 heads and with supporting bolt ons and tune and has the capacity to make 450+bhp engine.

LSX-PWR

yeah NemeSS knows what he is talking about. You can bore and stroke this engine if you want as well. A 3.90 bore with a 4in stroke will get you a 383in. Pretty stealthy I think.

NemeSS

iTrader: (127)

yea, it will make 383ci with 4.00 stroke

Hurley

NemeSS,

I see you're in Houston. I'm in San Antonio and I am having a hard time finding a 5.3 to start working on. Do you know of anything for sale in Houston? I would be interested in a bare block or even a full engine. I'm just trying to find SOMETHING.

Thanks!

John

NemeSS

iTrader: (127)

pm sent

ten5nova

I really didn't mean to say that I wanted to go to 5.7, I just meant that I would like to go as far as is safe for the iron 5.3 block. The only reason I want to do something with this block is that it only has 28,000 miles on it, and it's payed for. I like the idea of a 383 out of a 5.3. No one would ever know it isn't a stock displacment 5.3! My 5.3 with ported stock heads, and 230 @ .050/ 544 lift Lunati cam, and 750 QFT carb made 486 on motor, and 615 on N2O. So much potential out of such a small motor, I love it. You would never have made those kinds of numbers with an old style 327 without puting some major money into it.

JFM-jr

iTrader: (23)

On a side note does this apply to an iron block 5.3 as well? I have a local guy here with an carburated iron block 5.3 in a Mustang. Claims of course it's a stock bottom end he is spraying this motor. This guy has been on Pinks all out and money races so he's trying to bullshit the wrong guy LOL. I was just wondering how much cubic inch could be had from an iron block 5.3

ten5nova

nemeSS, is probably your man for that question. As far as nitrous goes, we gave my 5.3 a 125-130 shot, somewhere in there. Like I said before, on the stock short block. I've never sprayed it in the car yet however. I don't think I would ever try more than 150 on the stock pistons, and even at that, it probably wouldn't happen too many times.

NemeSS

iTrader: (127)

.060 over bore with stock crank = 336ci
3.9 bore with stock crank = 347
3.9 bore with 4.00 stroke =383
so he could be running a 383 or 347 disguised as 4.8/5.3 and taking everybodys $
but then again if its a in correctly setup fox with susp. and has been lightened. it possible hes on stock bottom end with a strong dose.
but if hes yankin em n/a, i would suspect hes not telling the truth about a stock 5.3 bottom end

chevellepowered

iTrader: (37)

and he could have it resleeved, and be over 400+ ci ,, but thats money to do that.. never kno tho,, my bet is he has stock crank and forged rods and forged 5.7 pistons 3.9 bore.. .and is spraying a heavy dose.. i would run that combo in my car..

NemeSS

iTrader: (127)

iron blocks are not optimal for re-sleeving. the process is generally easier and cheeper with the gen 4 blocks now. ls2 block and up.
although if the guy is hustling, it would make sense. but again if the car is leaving too hard n/a, no way its a claimed 5.3 bottom end

ten5nova

Hey NemeSS, just checked out your website, holy ****, looks like some nasty ****!!! I've seen your thread posts on here many times and just noticed your web link today. I'll keep you in mind for questions in the future.