I have a 74 350/400TH and currently have the trans pulled to install an SFI flex plate and high torque mini starter.

My intention originally was to unbolt the trans, drive shaft, crossmember...and slide it back for access to the flex plate.
BUT....as luck would have it, the battery-to-starter cable is shot so I ended up pulling the trans altogether for easier access to the cable.

Furthermore, the engine oil pan gasket leaks, as well as the valve cover gaskets.

All things considered, it would’ve been simpler to pull the engine and transmission as a combo, but here we are, at a crossroads.

If I’m going to pull the engine now, I may as well do a rebuild, and if I do that, I may as well spend a few more Benjamin’s and make some more hp.

I have found a good set of used vortec heads from a friend, as well as a bunch of good slightly used parts to make it a 383 stroker. He has a cast 400 crank, hyper pistons, and the vortec heads.
I’ll still need to source the cam, lifters, rockers, gasket set, rings, etc.

I really don’t “need” that much hp from a 383, as it is strictly a cruiser, but the factory 160+ hp is embarrassing, and would be all the more embarrassing if I got smoked by a minivan....just saying 😂

I guess my question here is, should I spend the extra dough to make it a stroker, for bragging rights, or just bore it 30 over, install the vortec heads, medium cam and headers?

If I go the stroker route, I may not be able to afford much more in the way of exhaust upgrades right away.

The engine that’s currently in the car is a 4-bolt main 350 from a 1982 3/4 ton truck. This swap was apparently done years ago and I have no idea of any other upgrades done except for Eddy intake and a Holley 600 carb.

Aside from the machine work, I’ll likely be doing the assembly myself. I have rebuilt engines before (a 4-cyl Chevy and an inline -6 Ford) and feel pretty comfortable rebuilding a 350. However, when considering a stroker, are there going to be unexpected clearance issues I need to worry about in addition to connecting rod bolt/ engine block clearances?
Would you recommend having the long block pre assembled by the machine shop?
Like I said, I’m really not looking for a street racer, just would like ~300+/- horsepower, but if I can get closer to 400+ without having to take out a second mortgage, I’d like that too!

From experience, how much more should I realistically expect to spend going the stroker route over just a 30 over, head and cam swap?

Are there other considerations am I overlooking?

Thank you in advance for your recommendations.

 

Ask member BKbroiler how he likes his 383 Vortec head unit.......I believe he even runs a modified Q-Jet. Low 12's.
Don't mess with 400 cranks and used Hyper pistons.....get a fresh rotator balanced buy Eagle or Ohio Crankshaft or many others......I like Eagle. The thing is that you will have just as much screwing around making old **** work together and you still have to balance it.......plus you have to buy rods anyway.
A decent 383 forged piston rotator with Eagle SIR rods and Cast Steel crank will run about $1100. It will have a balancer and flexplate as well. It will cost you close to $2000 with machining to build this 383 short block....deluxe with cam, lifters, timing chain, gaskets and timing cover.....I would use a dedicated Corvette oil pan.
Then....you have a pair of factory Vortec heads which will have to be checked and milled for .500+ lift at the guide boss....checked, assembled, new springs...etc. Count on about $600 by the time you are done.....but, the Vortec heads will support about 420 horsepower realistically without camming the **** out of it......that's good street power.
In the end....you will have an extra $1000 in the 383.....and the 383 will make about 30-40 ft/lbs. more torque but the same power.
When it comes down to would a do a Vortec 383 or a Hydraulic Roller 355 with aftermarket aluminum heads.....the 355 always wins in my book.....the 27 extra cubes are not worth it to me....unless you buy all new rotating components....the 355 roller alum-head unit will run much harder than a budget 383.

Jebby

 

Thanks, Jebby for the confirmation.

Budgetwise, I was already leaning towards the 355 as that will leave me more $$ to go towards the headers and eventually side pipes.

Before I purchase the vortec heads I’m going to take them to the machine shop to have them checked out.
I’m pretty certain that the 355 will be a little easier at the gas pumps, too.

Thank you for the sound advice!

Greg

 

Have your machine shop pick pistons out for you for your 355 build.......if you get pistons that are the same weight as what you have right now, no balancing is required but always suggested.
I do recommend forged pistons for your application. Weisco Pro-Tru units are a good value and come with matching rings, ask your machinist about them. Hyperutectic pistons are cheap but fragile if the engine is out of tune......
Wise parts choices and research getting components that work together can save piles of money......but you have to know what you are doing.

Jebby

 

IMHO - sounds like for your intended purposes, a 350/355 will do just fine.

What is the current 82 3/4 truck motor shape? How many miles? Maybe doesnt need a rebuild and you can cam swap, and drop those vortecs on.

Dont forget with those Vortec heads you'll need a new intake as your current intake wont match up

 

Since Jebby brought it up - either the 355 or the 383 will do what you want, but in my case, I'm using my original 77, 2 bolt block, with an Eagle cast steel crank in my 383. I have forged pistons. ORIGINAL reconditioned connecting rods and JE forged pistons. I have Vortec heads which, over the years, have quite a bit of work in them - pocket porting, valve guide bosses cut, screw in studs, spring pockets enlarged, pushrod holes opened up, surface milling and 3 angle valve job. I have a Qjet carb, Edelbrock air gap intake and 1 5/8 primary headers. I have a 225/232 duration hyd roller cam which is quite mild on the street with good vacuum. The car has tremendous throttle response and low end power and has run 12.15 at 110 on the track, on drag radials. I have over 250 runs on this set up and 10K street miles, so it is reliable.
With hyper pistons, instead of forged, and a good flat tappet cam, minus some head work, you could come close to the same results for very little money.

 

The truck engine is in pretty solid running condition. I have no earthly idea how many miles the engine, or the car for that matter, have on them. I purchased it a couple months ago with a broken speedo cable....and according to the PO, it’s been broken for years.

I figure, at the very least an overhaul, but in an effort to not get smoked by a v6 minivan, I’d better do some mods while it’s out of the car. And not knowing how many miles the engine has, I think it would be a safe bet to go ahead and magnaflux it, bore it and add new heads w headers, intake and possibly a cam.

I agree with you guys, that for my current needs (cruising and drag racing minivans) the 355 will be the more reasonable option....

If I go for a cam, what setup would you recommend? I understand some of the basics on how cams operate, but not so much the technical numbers, duration, etc...

Thanks,
Greg

 

The bores are the main driver of the 350/383 decision. Serviceable bores can save the existing rotating assembly. Once you need a bore job, the stroker is not much different in price. The new SCAT crank is like $230 which is close to the cost of a crank regrind. Pistons are already needed so no difference there. Rods can be reconditioned or replaced for almost the same price.

It is easier to make power with more cubes and the torque will be better in the street RPM range with the 383. If you need to replace the pieces anyway, just do it.

 

All for stroking it if you can, heads upgrade is a must though. Torque is what pushes you back in the seat, cant have enough for a driver.
Doesnt have to be radical just pulll hard. Id never go back to a 350 again.
As said with a GOOD head you dont need a bunch of cam to make a 350 run good and yes it can hit your goal...just saying its always easier with more cubes.

 

400 cranks have bigger mains and can't be used in a 350 main block. Unless you align bore the mains which will weaken the main caps. Or the other bad idea is to machine the crank to 350 mains to weaken it also.

Like years ago the offset ground cranks to get 3.90 strokers out of 400 cranks

 

Heck, you can brag about your engine being a "stroker" even if its not! Lots of folks do that...put higher 'cube' badging on the car, etc, etc. Talk is EASY.

If you really WANT to have a stroker engine for the power, pull out the wallet. On the other hand, you can freshen up the engine and boost the power WITHOUT displacement change and without spending all those 'Bennies'. Good quality gaskets to seal the leaks, vortec or other better flowing aluminum heads, much better cam, free-flowing exhaust system, recurved distributor, tuned up carb, and you are set to go. You DO NOT need to change the induction or ignition systems, unless yours are in bad repair or malfunctioning. The Q-Jet will be equal in performance to any other carb you might choose, and it will be MORE economical than any other carb design, if it is in good condition and adjusted properly.

 

Turning down the crank a much better way to go, and it lets you add a larger radius for more strength.

 

I built my 383 back in the days before aftermarket cranks were cheap and common. Used a turned down 400 crank. That’s the way it was done in those days. (Gawd I sound old.) Long story short if it’s not to late, broke the crank. My advice - if you have to rebuild the engine, go for the 383. You’re buying pistons anyway and a stroker crank is not much more than refurbishing your stock crank. You can get a lot more power out of your 350 but ‘there’s no substitute for cubic inches’.

 

If you are needing an overbore and new crank definitely go stroker.

 

Sensible package. The 12.15 came at?

1. Lebanon Valley
2. Atco
3. Englishtown

 

compression, cam timing, airflow that's what you need for power no matter what you build

 

I dont believe there was a 160hp option in 74.. The l48 my 74 came with was rated at like 205hp if I remember right but yeah Id go with the 383 simply because I decided to just do the 355 rebuild thing with a replacement 4 bolt block and flat tops and with the 3.08 gearing I still wish I had more power.. so much so I was actually contemplating ripping the engine back out. however I think in reality I would be better served swapping the transmission with a 200r4 for overdrive and changing my rear end gearing.
I went with the voodoo 262/268 cam myself for more torque.

 

This was my thoughts at the time too... Now if I had to do it all over again myself I would buy a non forged scat complete balanced 383 scat rotating assembly which is still at least 30% stronger than the stock cast l48 setup with a cast steel crank vs cast iron and fine for a mild street 383 2 or 4 bolt block. They sell for under $700. If your planning on going to the drag strip or pushing it hard than the forged stuff is worth it IMO but not in a build where someone has a case of while im at it and just wants more get up and go..
I Ended up buying new OBX stainless sidepipes for about $650 shipped on ebay and made covers for about $50 So make sure you do some looking before buying as they are sold by many distributors these days I bought and built my entire car on a budget which came out to just over 9k with the new door panels I just bought complete the interior replacement and I had to replace /redo quite a bit including the body/paint work, wheels steering, engine and interior. Your never done though since in my hast to get to driving it I skipped over replacing the bushings and suspension components which of course im pulling things apart to done now after the fact.

 

Englishtown RIP. I race at Island Dragway now. Best ET there is 12.18.

 

Arent you getting the itch for 11’s yet or are you in “ain’t broke, don’t fix it mode?”

Jebby