Hey guys looking at rebuilding my stock 350 to a 383 stroker. Goal is 450-500hp reliable reasonable mpg and streetable. Looking for 0-100mph power primarily. I understand there is heaps of variables when it comes to building an engine but I would like to get a rough rough ballpark on the cost of building a 350 to a 383 before I go to an engine shop.
So…. How much roughly will something like this run.

Thanks
-Connor

 

Well, balanced 383 rotating assemblies start out at about $1500 for (cast components which are fine for most mild sub 6000rpm builds) then you likely need heads and all the other goodies. I have no idea what engine you have now but if its the 2 bolt l48 and your really looking for 500hp you may want to consider a crate engine. Crate engines are often cheaper than local shops as much as that doent make sense and if you looking to drop the car off and have a local shop do everything your likely going to pay much more.

I can offer you number based on what I did. I scoured facebook, craigslist and ebay for months collecting parts for my build which was a 355. I got a fantastic deal on a freshly machined 4 bolt block with a set of 30 over flat top pistons and rods from a shop that was cleaning out space for $300. All together with the roller cam and new aluminum heads I put in this year and all the accessories my roughly 400hp engine cost me 2800 at this point without the stainless sidepipes which were another grand with the chambered inserts and shields... so 3800-4000 from air cleaner to exhaust tip with the aluminum rad and electric fan setup. When factoring in labor you typically double the cost of the parts but it would have cost me much more to buy everything retail so... also I used a scat cast steel crank and hyper pistons so my engine is only safe for about 6000rpm tops which is more than I need. I ended up watching a lot of youtube and doing a lot of reading on forums and tackled everything myself because otherwise I would still be saving or lost interest by now.keep in mind it I built the engine in 2012. but added a new carb, electric fans, roller cam and heads in the last 2 years. I sold the old stuff so didnt factor that into my pricing above. Keep in mind these prices vary a LOT. There are folks here that have as much $ in their heads and exhaust and I have in my whole setup. I'm frugal and have other financial responsibilities.

 

For a quick + easy solution, places like Blueprint and ATK will give you a basic 383 for about 5-6k.

I bought an ATK one a couple years ago for the Chevelle. It was about $6k if I remember, and I was able to run down to Summit and pick it up same day (on a Sunday, no less). It runs runs great and makes 500+ torque, which is great for street use.

 

heres another well known builder... personally Id consider the newer roller block option. https://www.mabbco.com/catalog/auto/...urer/chevrolet they do have long blocks as well and can even turn yours into a 383 but with shipping it may not be cost effective.

before jumping into any impulse buys I would do plenty of reading and research. 500hp will likely mean you will need to beef up other things like the rear end.

 

That sounds like a good idea. What I have read on the forums supports that as well. About how much is an install going to be at a shop for something like that?

 

What's reasonable mpg for a 500 hp stroker?........

 

Those two terms shouldn’t be used together.

Everyone wants a 500HP engine, but most don’t want to do what’s necessary to make a car streetable .

A 383 with AFR 195 heads, 236 degree cam, 10:1+ compression should be close. That also means a stall converter if it’s an auto and gears.

 

step up to an all brand new, genuine GM crate.
https://www.gmperformancemotor.com/c...er&Per_Page=-1

 

If you want the most reliable crate...and an honest 500hp call Mark
Stellar reputation it wont break. Not done by a bunch of hourlies

https://vortecpro454.com/

 

I assume you are looking for 500 crank HP? 500 RWHP is going to take a bit more cubes like a 406 to keep the engine more street friendly. To get to any where close to 22 mpg you will need a OD trans with a lock up converter. Gears maybe 3.73's or 3.55's to bring the rpms down a bit.
Either way roller rockers, roller lifters. Maybe fuel injection? Chassis dyno tune to get the air fuel ratios spot on.
Good luck with your project.

 

what transmission are you going to run and what rear end gearing. Alot of the power you are going to feel is the torque. If you really want it snapped you want a 3.70 or deeper rear end ratio. IF you run an M21 then 3.70 or 4.11 is a definite as first gear is pretty high. If you want highway drivability you want a 5 speed. Look at the first gear ratio on the 4 speeds as a M20 wide ratio is about the same as a TH350 so the 3.55 would be okay off the line bu t still not snappy.

 

On that, I have no clue.. I did the install myself 🙂

 

Im swapping in a2004r and 3.55 gears just so I dont have to stop at every other gas station I pass.... The more power I set my engine up for the more gas it sucks when I went to the bigger roller cam, mileage suffered this summer when I went to the larger runner aluminum heads, rejetting and larger squirters were needed and mileage suffers even more... Its to be expected and as Rescue Rogers pointed out with an overdive trans you get a large improvemnt in fuel economy with also allows you room for the deeper rear end ratio to put more power to the road from takeoff

 

True...long as with that gear you arent lugging it. Carb'd engines with OD just dont tolerate it..and mpg is best with the engine being in its happy zone. May be at a higher rpm than youd guess rather than being lugged down.

Ex my 2002 Silverado 3.73 gear stock 5.3 got exactly the same mpg at 60, no more than 65 in D than it did in OD.
I never use OD unless Im gonna get on the hwy plus less wear on that big 3-4gear drop (clutches)

 

Those roller blocks, both the vortec and the non-vortec ARE really good value.. Never come across those guys before; good link!

Adam

 

Those are about the cheapest ones on the planet. Read the fine print before ordering.
GM crate is only afew hundred more last time I checked for their 350.
More than 1 guy has found his cheap crate from xxx was either .060 over or .030 and one cyl was .040, sleeved etc.
You get what they give ya.

 

The Mabbco 383 Roller Block short block + these ATK 185cc / 70cc heads for $517.50 each (Profiler SBC heads -cast in Ohio are fantastic and have "regular" height exhaust ports vs. the raised exhaust ports of the regular Profiler casting), combine with a good roller cam, cheap OEM roller lifters (or LS7 lifters) because of your roller block shortblock, and an intake with a Felpro 1206 size, and headers and 475 hp and plenty of torque sounds like a good ball park.

https://www.high-performance-engines...p/sbc70185.htm

If you care about MPG add a Holley Sniper and ignition control and tune the ignition timing and lean out the highway cruise area.

I can't think of a cheaper way, assuming your comfortable doing the top-end.

-I'd swap the heads to 7/16" rocker studs, though for more valvetrain stability / less loss of lift, if you're going with a nice modern aggressively lobed, high lift CAM, which you should with those heads.

Adam

 

Ive read this before but honestly I question how much its the carbed factor vs which cam is in the engine and how much lower end torque was given up for high rpm hp... The 2004r im putting in was likely bolted in that monte ss with 3.08 gears connected to a carbed 305 unless im wrong? at least thats what my buddy had in his old monte carlo ss.

im kinda kickeing myself for not picking his old car up for 1200 bucks now because it was in excellent shape and sitting in his moms garage across the street for like 10 years. T tops and all the velour I could handle...

 

Someone on another forum used them a couple times with good results... The prices seem really low but if you add up the extras you can select they are just low.. I actually considered a 406 from there...

 

so, why buy the absolute cheapest short block? that's asking for trouble especially if you beat on it! Cheap probably has cheapest rebuilder pistons with thick heavy ringpak? And, block may be bored to (or past) practical limits.
instead, buy a viable roller core motor and rebuild it yourself. And, many good auto machine shops do have the jig/fixture used to complete an incomplete mech fuel pump mount. you can make your own jig as well youtube. It's not practical to $purchase$ a jig for just one job. FYI, most 880/L31 blocks have minimal bore wear.