383 advice

[ttjordan25]

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Hello every one!

Its been a while since Ive been on here, but I decided to turn to you guys for suggestions on my task at hand. I have an 86c10 fleetside, and I'm wanting to replace the 350 with a 383 stroker. I am struggling with which route to go, meaning forged or non forged, Flat top or dished pistons. Should I go with a stroker kit or buy piece by piece... Im really wanting to get into the 500+hp range, but would like to stay on 93 octane , so im guess 10.5:1 cp?

Here's what the c10 has on it already
Early model 350 SB
Comp XE274 flat tapped cam ( thinking of moving to a retro roller)
Comp Ultra Gold 1.5 roller rockers
Edelbrock E series Alum. Heads 210cc ( part number 8085) I think
EdelBrock RPM Air gap intake
Holley 650CFM
700r4 Trans ( TCI TB and Shift Kit)
Eaton Tru-track Diff
Motive 3.73 gears

I know with those head If I move to a retro roller the springs will need to be changed. Will I have a problem with fitting the new springs? I kind of clueless on what deck height I need to go, or piston cc to stay within. Sorry I need some hand holding as this is my first stroker motor, and I want to build it to accommodate the heads I already have.

Any suggestion would be greatly appreciated! Please let me know if more infor is needed

[aotte1]

At your requested H.P. you are looking at around 1.3 HP per cubic inch. At this ratio you are above typical street HP levels. Therefor their will also be effects that will likely need to be covered in the drivetrain. Their are several books on SBCs that describe builds with dyno results, often available at the big book stores. Good luck.

[68c10owner]

For 500+hp you will want a forged rotating assembly and no more than 10.5:1 if you want to run pump gas. Then contact Chris Straub, http://www.straubtechnologies.com/ for a custom roller cam to work with those heads and it should be well over your goal.

[RUN GMC]

another good place to look is here for engine kits.....................

https://www.enginekits.com/stroker-k...ock-chevy.html

[68c10owner]

Originally Posted by RUN GMC

another good place to look is here for engine kits.....................

https://www.enginekits.com/stroker-k...ock-chevy.html

Be carefull with some of their kits. The cheaper kits use cast pistons which won't hold a lot of compression or high HP.

[ttjordan25]

Thanks guys. I've been looking at some of the Eagle and Scat kits on Summit

[cableguy0]

At a legit 500hp the factory block comes into question as well. At a minimum you will want a 2 bolt block with 4 bolt splayed caps added. You will want the block sonic checked for thickness and all machine work needs to be right. The other option is an aftermarket block which isn't terribly expensive once you factor in the work your block will need to hold the power reliably. The xe274 isn't going to get you near 500hp. You will want to go roller and in the rpm range you will be operating in you will be pushing it with using a hydraulic roller. A solid roller is probably the best option. You need a forged rotating assembly. Forged crank, Forged rods and Forged pistons. You will need a GOOD machine shop to do the balancing work to make sure its perfect. You will also want to go to that shop before you start buying stuff. You should also probably be looking at Afr or Brodix heads especially if you have any intention on the + after the 500hp. A true 500hp build that will actually stay together isn't cheap. You wont get to that power level by throwing a bunch of parts together.

[ttjordan25]

I thought about just ordering am aftermarket block, but I started reading some reviews of people complain about there being so much surface rust that it had to be machined again once they got it. Also some were saying they weren't within the spec... IDK maybe these were referbs.

I started mentally comparing the price of a aftermarket block vs the money I would have to put into the block I already have. I was afraid I was going to be told the heads I have weren't set up to handle or get me close to the 500 mark...

[DMT]

You would be better off concentrating on torque rather than HP for your street driven truck with a small block, even if its a stroker. A BBC could get away with that amount of HP and have the torque to get the heavy truck moving on the street without swapping in numerically larger gears.Plus with a dual plane intake you're limited on RPM to get to your HP goal.

A 400-460 max HP with the max torque being close or even more than the HP goal would be a whole lot more funner to drive on the street with the RPM range lower than what a sbc 383 would need to spin to get to 500 HP with it in a heavy truck.

I have a very mild Comps cam XFI hyd. roller grind in my 4,400 lb '65 Chevy Impala with a sbc 383 in it that runs 13.2s in the QM. The cam has 206* intake and 212* exhaust duration @ .050" with .550" intake lift and .546" exhaust lift with the called for 1.6:1 rocker ratio. The car has a 700R4 with a 3.07 rear gear in it with 28 inch tall tires and a 60 ft time in the 1.8s with a 101 mph trap speed. The car weighs 4,620 lbs with me in it. That calculates to over 400 HP and has 22 in hg at idle that is very smooth. When I was researching cams I looked for the highest lift with the smallest duration @ .050" I could find and the Comp Cams XFI fit that bill and worked out really well with 9.8:1 static compression that I run 89 mid grade with no pinging. It makes power to 6,000 RPM maybe more if I had the right springs on it?(I have the springs that came with the heads on it)

The car gets over 20 mpg on the highway with the 700R4 overdrive trans and that cam with the 3.07:1 rear gear. With the 28" tall drag radials on the car with the 3.07:1 rear gears its still very hard to get traction from a dead stop with the 1st gear of the 700R4 on the street with cold tires that have 32 psi in them. At the track with around 18 psi and the drag radials warmed up is a bit easier to get traction, but even then some times the tires will break loose at the track. Your gearing will factor in how your truck runs as well.

Torque is king on the street, the above car is VERY fun to drive on the street and will get up to the speed limit in no time flat. I think my aluminum Patriot Performance heads are 185cc intake runners so with your 210 cc intake runner heads the same cam would make even more HP than what mine does with possibly a slight penalty down low. TORQUE! GL

[ttjordan25]

DMT that seem like the more reasonable route. I honestly looked for just a little street beast to drive around town and to the track on occasions.

[Marv D]

Originally Posted by ttjordan25

I thought about just ordering am aftermarket block, but I started reading some reviews of people complain about there being so much surface rust that it had to be machined again once they got it. Also some were saying they weren't within the spec... IDK maybe these were referbs.

I started mentally comparing the price of a aftermarket block vs the money I would have to put into the block I already have. I was afraid I was going to be told the heads I have weren't set up to handle or get me close to the 500 mark...

Aftermarket blocks like the World/Motown or Dart do not come 'ready to assemble'. The bores are left small at the factory so they can be finished to YOUR piston configuration. It would be foolish of them to finish hone the bore to a 'one size fits all' forcing you to use cast or forged or some predetermined piston wouldn't it??? Before assembly the aftermarket block WILL spend time at your machinist, so the 'surface rust' (which I personally have never seen except in one old Motown block that was on the shelf at my machinist for many months) is a moot point.

In selecting your block and components,, just keep in mind the old saying about building a castle on sand. Wise men just don't do it!

500+ HP unboosted on pump gas with those heads and only a 4" bore is going to be a tricky deal. Absolutely possible, but is not going to be a fun worry free low maintenance motor. IMO you would be much better off forgetting about the magical mystical HP numbers and build a nice hydraulic roller motor with torque from 3000-6000 and enjoy it. A cam with something like the Crane/Comp XR 294, 1.6 rockers to make all the lift possible to get those heads working, build for ~ 9.6:1 static and let it eat.

[68c10owner]

A stock block will handle 500hp pretty easy. 4 bolt main with studs if your worried about it. No need to spend the extra money for a aftermarket block at this power level unless you are wanting to build something over 400 cubic inches.

Your heads will support 500hp. You will need a roller cam and a custom cam matched to the heads is what you need which is why I suggested Straub. Give him a call, knows his camshafts and he will tell you what the HP should be given the specs of the engine. He usually under estimates them so I think you would be happy.