5.7L Vortec Part Recommendations

[76SeaRay]

I have a heavy duty (4 bolt main) 5.7L Chev Vortec block (late 90's). I am looking for recommendations on parts to buy to build it up. It has a stock crank, cam and pistons as near as I can tell. I think this was a truck engine due to the 4 bolt main. I know all the arguments for and against a truck engine but I haven't found a donor marine version. I am not interested in buying a rebuilt from engine builders for a couple of reasons. I like working on engines, I like to know what's inside when I do it, and I have lots of time to get a good quality build. So, that said, what parts are recommended for a good solid engine without trying to get carried away on performance? I will be using a marine Rochester 4 barrel that is already rebuilt and tested. I also have a new marine water pump. It will be driving a Mercruiser Alpha 1 so targeting about 300hp. It is a cruising boat.

I need recommendations and part numbers would be great for a starter, manual fuel pump, distributor, oil pump, roller lifters, cam, brass freeze plugs, valves, and gasket set. I don't want to get into the whole "quenching" thing and custom specs so I am guessing stock pistons are fine, however, if the machine shop says I have to bore the engine, then I would be looking for recommendations on pistons that don't require sorting out the whole compression ratio thing either. If there is a list on here somewhere already, please let me know where to find it or if someone can post a list of part numbers and source that would be great.

Thanks.....

 

[Scott Danforth]

Post the block casting number. Late 90s truck blocks do not have the boss machined for a mechanical fuel pump.

Stock 4-relief pistons are crap

What is your budget, and your ability? By the questions, you normally dont work on SBCs

 

[Bondo]

however, if the machine shop says I have to bore the engine,

Ayuh,.... This should be assumed true,.....

A rebuilt motor that hasn't been bored, ain't a rebuilt motor,.....

 

[Scott Danforth]

here is the only late 90's Gen 1 motor that had 4-bolt mains (zz4 crate motor)
10243880...350...95-00...2 or 4...Vortec truck, Gen.I crate motors and "ZZ4", roller cam, one piece rear seal https://www.mortec.com/castnum.htm there are a few early 90's. just dont try to use the gen ii blocks (LT1 with reversed cooling)

 

[76SeaRay]

I have built a lot of pre-1986 SBC's (Camaro guy), just not up to date on parts for vortec's or marine. The block is an 880 casting 4 bolt and it has the boss for manual fuel pump. I wouldn't mind changing the pistons to something else but don't want to go through a bunch of effort over compression ratio determination etc.. So, if there is a better piston that is a direct replacement for the stock one, I would go with that and have it bored if necessary...

 

[Bondo]

and it has the boss for manual fuel pump.

Ayuh,..... The boss stayed, but it ain't machined for the push-rod/ cam follower,.....

 

[Scott Danforth]

first, with a used block, you should plan on a line-hone, deck, bore and hone. your looking at a .020 over-bore at a minimum

the 880 block or
10243880...350...95-00...2 or 4...Vortec truck, Gen.I crate motors and "ZZ4", roller cam, one piece rear seal
is a crate motor. it may or may not have had the fuel pump boss machined. dont sweat it, a carter universal marine fuel pump kit is under $80

for heads, you want stock vortec heads that have been modified with screw-in rocker studs and have been modified for cam lifts above .420 (involves machining the seal bosses and different seals)

freebeetony did a good write-up https://forums.iboats.com/forum/eng...ves/10679827-vortec-head-modification-upgrade

a new set of heads is about $800 (wait for the sales) https://sdparts.com/i-19958322-chev...MI-Jzs9JG45QIVCIeGCh3yFgKhEAQYASABEgJNX_D_BwE

a bit more from scoggin dicky if you have them mod them https://sdparts.com/i-23901396-sdpc...der-head-with-0-525-valve-spring-upgrade.html

as for pistons, you want an LCQ style piston with vortec heads. KB has them in both cast and hypers. these are usually the cheapest when packaged with a complete rotating assembly (see below)

stock rods are junk unless that is all you can afford. they are a pressed-pin style rod, and the machine shop will charge you $40 just to press the pins out. if they need re-conditioning, new scat forged rods will be much much much cheaper than paying for re-conditioning

if your crank isnt perfect, get a price on getting it re-conditioned. compare that to a brand new crank, you may be cheaper to buy new

I personally like Comp Cams because over the years they have helped me often. i would go with an XM264HR cam and lifter kit. its a great marine cam, providing a fatter curve than the stock cams

roller tip rockers are my recommended go-to. about $100 from summit. however if you look around, you should be able to find a good used set of vortec heads with all the machine work done and with roller rockers for about $400. the rules changed, so most of the race car guys are now using AFR's and other heads vs the vortec's. many machine shops near race tracks probably have 10-15 sets of heads on the shelf collecting dust now.

if you decide to go to a 383 stroker, now is the time, as the cost of the rotating assembly is only a few $ more (under $30 difference). call the guys at competition, they have good pricing on rotating assmblies. https://www.competitionproducts.com/ also work with your local machine shop, they usually can match pricing.

with a 3.48" stroke, your looking at a 12cc KB pistons for a CR of 9.4:1, a 0.005" deck height and a 0.041" gasket. running 3.75" stroke, suggest a 18cc KB piston for a CR of 9.4:1

then top it off with an edelbrock marine intake (with the dual alloy casting) or the RPM air-gap and run a heat exchanger.

use a carb spacer to increase plenum volume.

a 5.7 running above will be about 320hp or more at the crank, a 383 will be about 360 or so at the crank without a sweat.

 

[76SeaRay]

It is an 880 block with 5.7L SGI embossed on it and block date code is either C145 or G145, can't quite tell which for sure so I assume this is a very early 1996 vortec.

The block had non-rollers in it but is machined for roller lifters and I have the "retainers" for it.

Thanks, the boss is machined for the mechanical fuel pump. There seem to be a lot of mechanical marine fuel pumps for sale for it.

I thought the stock heads are set up for .453 lift already so was thinking a cam that goes with .447 to avoid having to modify the heads.

I didn't see any mention about valves to be anything other than stock (ie, no need for stainless valves?).

Thanks..​

 

[Scott Danforth]

its the heads that make it a "vortec" so how many intake bolts are on it.

if it was a 1996 block, it would have the retainers machined and would have had a roller cam.

however if the block was a 1995, it would not have had the roller lifters.

stock heads are good to about .420, some, and I repeat only some could go to .450. depends on how sleepy the guy doing the machining was.

its a $50 charge to get the the seal spuds cut. and you get better seals to boot. about $100 if you also have the head modified for threaded studs (highly recommended)

 

[76SeaRay]

It is a short block so I need to get a pair of heads and an intake for it. Since I need to do that, I could have them modified to go to the higher lift. Again, not looking for super high power, just good cruising performance and reasonable fuel economy. I don't know what an LCQ piston is but I looked at the KB135 based upon your suggestion for KB. Or is there a more direct replacement?

It does have the retainer area around the lifters machined even though it is non roller. Sounds like a transition block...

 

[Scott Danforth]

Blocks as far back as 1988 had roller cams.... Trucks were hit/miss from 1990-1996. Just not boats until 1996

 

[76SeaRay]

Picked up a pair of 906 heads today... So need to find a good vortec intake manifold for a Rochester Q-Jet.... Just started looking on Ebay but need to understand the number of water ports required at the front of the manifold.. Back to research...

 

[Scott Danforth]

stock cast iron, or a marine intake that has the bronze water passages.

I picked up a NOS Volvo Penta manifold a few years back for under $300. made by Barr (same casting house as Edelbrock).

you can get a new edelbrock marine intake https://www.edelbrock.com/performer-rpm-vortec-marine-intake-manifold-2516.html

or switch to a heat exchanger and run anything you want for an intake.

 

[Scott06]

In addition to what scott lists above I have one of these that came with a extended base engine works well if you want cast iron .

https://www.michiganmotorz.com/vortec-cast-iron-intake-manifold-1996-current-p-465.html

 

[Scott Danforth]

here is the same intake on ebay for $200 https://www.ebay.com/i/142277853464

 

[Scott06]

They look very much alike in terms of casting but the eBay one is from Engine Quest. The Michigan motors one has no engine quest casting by the distributor hole but rather has a XF cast there. Not sure if they are cast for different customers at same
place or if there is any appreciable difference In Quality.

 

[Scott Danforth]

not sure about differences in quality.

i personally would jump to an HX on a new engine build, then run a much better intake for mid-range

 

[76SeaRay]

Don't know what you mean by HX for the intake. I did see the ones on Ebay but wasn't sure what the quality would be. I am headed over to a couple of machine shops to "interview" them on what they know about vortec heads. I am thinking I will get the heads done first and then the block to match (meaning pistons and cam). I am thinking that I will go with 1.5 or 1.52 roller tip rockers and have the heads machined for higher lift or use beehive springs. Right now it looks like the Comp Cams XM264HR but don't know what part number of roller lifters and piston to go with to match the higher lift. Still researching those. Again, targeting 300Hp since I am running an Alpha 1 and looking for lower octane fuel use since this is primarily a cruising boat.

 

[Scott Danforth]

HX = Heat Exchanger.

with a heat exchanger, you can run any intake you want, as the raw water would not ever get to the intake

get a complete cam and lifter set or a complete "K" kit which has cam, lifters, and timing set.

Pistons will be determined by your bore and stroke and head. you wont need to worry about the cam as you already picked the cam and there is not enough lift and duration to ever come near the pistons.

best bet is to have the seal boss machined for the better seal (which allows clearance for higher lift cams) and also convert from pressed in rocker studs to thread in.

 

[76SeaRay]

Well color me with sticker shock.. I know it has been a while since I had heads done.. The shop I just went to quoted me about $1,000 to do the heads.... I think I will back off a bit on this and go back to a budget approach... Probably buy the tool and cut down for the springs myself or just get the Comp Cams beehives... Then have a shop just do a 3 angle grind..