View Full Version : ?'s about 350 SBC conversion to 383 stroker


Ztwo8
12-11-2011, 01:46 PM
OK so long story short, I bought back my first truck (83' C-10) and before I sold it, i put a newly rebuilt 350 out of a 69' vette. Apparently he let it sit for a year or so and tryed to run it, without changing any of the fluids :bang: so now it has rod knock and has to be rebuilt anyway. so my question is what is important for me to replace? I have seen several different types of kits. Everything from almost a complete motor to pistons and heads. Or in other words what do I need to do a complete 383 swap? Thanks for any and all tips and advice!

dkcoleman01
12-11-2011, 02:42 PM
Get your block bored .30 over with a 3.750 in. stroke crank with 5.7 rods or 6inch rods get new cam bearing, freeze plugs. You can also go the easy way and buy a 383 kit, (pistons, crank, rods, flexplate, balancer, rings, bearings, already balanced) if you look on the internet (summitracing.com, jegsperformance.com)you can get them for about 900 bucks...

Ztwo8
12-17-2011, 07:33 AM
Get your block bored .30 over with a 3.750 in. stroke crank with 5.7 rods or 6inch rods get new cam bearing, freeze plugs. You can also go the easy way and buy a 383 kit, (pistons, crank, rods, flexplate, balancer, rings, bearings, already balanced) if you look on the internet (summitracing.com, jegsperformance.com)you can get them for about 900 bucks...

Why should I or why do i need to bore it out? (inexperienced) Yeah I have seen some kits which is what I was planing on doing but now that you say to bore .030" over, I am not sure if the kits are for a stock 350 block or one bored out. I will have to look extra careful now. In your opinion would it be wise to swap cams? I don't plan on racing at the strip with it. just have a weekend truck that has a little backbone :)

newschool72
12-17-2011, 07:54 AM
If u buy from a reputable company, u can let them know what u have , stock bore or .030 or .040 or .060. They will sell u the proper pistons. The main reason for boring the engine would be to clean up an old bore to get the right tolerances for proper ring seal and piston to cylinder wall clearance. It also ups the total cubic displacement of the engine.

MikeFSKSpeed
12-17-2011, 08:02 AM
If u buy from a reputable company, u can let them know what u have , stock bore or .030 or .040 or .060. They will sell u the proper pistons. The main reason for boring the engine would be to clean up an old bore to get the right tolerances for proper ring seal and piston to cylinder wall clearance. It also ups the total cubic displacement of the engine.


I just built a nice lil 383 myself. You really have to get the right rotating assembly because when you up the stroke, the pin height moves up higher on the piston. I mixed and match with an Eagle Triple Lightweight Crank, Manley Rods and SRP Pistons.

The two area that most often need to be looked at for clearence are the oil pan rails (which are pretty much always notched) and the cam. With my setup the Manley rods were very large around the bottom end so I went with a smaller base circle cam to give clearance from the rods.

All in all they are very easy to build nowadays. With a solid roller and a set of AFR 210's I dynoed it at 578hp with 93 octane.

PM me if you have any questions, we build a lot of 383s in our shop.

dkcoleman01
12-17-2011, 09:13 AM
Why should I or why do i need to bore it out? (inexperienced) Yeah I have seen some kits which is what I was planing on doing but now that you say to bore .030" over, I am not sure if the kits are for a stock 350 block or one bored out. I will have to look extra careful now. In your opinion would it be wise to swap cams? I don't plan on racing at the strip with it. just have a weekend truck that has a little backbone :)

To make a 383 stroker you would have to bore it .30 over to make it a 383...If the kit is for a 383 stroker then it's either going to come with the pistons in .30 over making it a 383.. they can come .40 over which would be a 385 stroker, also last .60 over and that is a 388 stroker. You want an 383 stroker so you would get the kit that has the .30 over pistons. As far as the cam swap If it was me doing it, I would go with all new parts so yes I would change the cam. There are several companies on here that will custom built you a great 383 stroker if you want to go that route...

Ztwo8
12-17-2011, 09:17 AM
I just built a nice lil 383 myself. You really have to get the right rotating assembly because when you up the stroke, the pin height moves up higher on the piston. I mixed and match with an Eagle Triple Lightweight Crank, Manley Rods and SRP Pistons.

The two area that most often need to be looked at for clearence are the oil pan rails (which are pretty much always notched) and the cam. With my setup the Manley rods were very large around the bottom end so I went with a smaller base circle cam to give clearance from the rods.

All in all they are very easy to build nowadays. With a solid roller and a set of AFR 210's I dynoed it at 578hp with 93 octane.

PM me if you have any questions, we build a lot of 383s in our shop.

Thanks for the information! on a side note what would you guys charge for me to ship you my LS1 out of my 00' maro to make it a 383?

FowlerMotorsports
12-17-2011, 09:22 AM
Like Mike stated you must watch your clearances, we had cam clearance issues and it didnt agree with us at all.

And always be sure to run the right octane with your compression ratios!


http://a7.sphotos.ak.fbcdn.net/hphotos-ak-snc6/179851_1414303416161_1789842661_768596_2333312_n.j pg
http://a2.sphotos.ak.fbcdn.net/hphotos-ak-ash2/181594_1414303656167_1789842661_768598_4813608_n.j pg

Ztwo8
12-17-2011, 09:24 AM
To make a 383 stroker you would have to bore it .30 over to make it a 383...If the kit is for a 383 stroker then it's either going to come with the pistons in .30 over making it a 383.. they can come .40 over which would be a 385 stroker, also last .60 over and that is a 388 stroker. You want an 383 stroker so you would get the kit that has the .30 over pistons. As far as the cam swap If it was me doing it, I would go with all new parts so yes I would change the cam. There are several companies on here that will custom built you a great 383 stroker if you want to go that route...

Oh ok I get it thanks a lot! I would have some one build me one but I rather not spend a whole lot of cash. Plus I want the experience of doing it myself. i have a garage full of tools. And equipment to pull a motor which I was able to borrow from a friend. I just want to get my ducks in a row before I went all out and bought stuff that is inferior or wrong altogether.

Ztwo8
12-17-2011, 09:30 AM
Like Mike stated you must watch your clearances, we had cam clearance issues and it didnt agree with us at all.

And always be sure to run the right octane with your compression ratios!



:shocked: damn...I will double, no TRIPLE check everything!

FowlerMotorsports
12-17-2011, 09:54 AM
My next 383 will be gone over with a fine tooth comb! You will love the power and torque they put out. We decided to have a 377 built, 400 block with 350 crank, and it will out run anyone on the top end, but bottom end is where its at! For sure go with a 383, you will never want anything else! (Unless you have a big budget)

Ztwo8
12-17-2011, 10:08 AM
Yeah I helped my step dad back in high school build a 377 for his 55' bel air. IDK if it was him (he was a master tech) or what but it ran rough and didnt seem right. lol that scared me away from 377's! lol oh well. And no my budget isnt that big but I wont skimp out on putting lamer parts in to save money. I want my truck to run for a long time!

newschool72
12-17-2011, 10:16 AM
The last 383 i built for a buddy had a clearance issue on the camshaft. we put short block together and rotated the crank a couple times and noticed a hard spot. found the culprit in the connecting rod bolts. a little dremel work and the problem was fixed. we ground the bolts till we had about .040 clearance. He has about 2000 mls on it now and everything is doing well. in a full bodied 3rd gen camaro he has gone a best of 11.74 at 114. Its his daily driver.

FowlerMotorsports
12-17-2011, 11:42 AM
A 383 is my next build, I am about to go to the shop and finish up my 362 considering my .60 over rings finally came in!