[Danimal]

Hey All,

I no longer have my '69 GTO, but thankfully it's in the hands of someone with the time and resources to take it to the level it deserves.

What I *DO* have is the 283 from my '64 impala (the later I no longer have), which I am preparing to replace the 4.3 V-6 in my '97 S-10 2wd. I've gotten some good information about the swap itself (not an original idea at all =) ) from the s-10 forums, however what I need is some input on how the engine should be set-up to run optimally in the S-10. The engine ran very well in my '64, despite the cars size, even with the factory Powerglide and standard rearend, ratio unknown.

I rebuilt it myself back in '92 and here's the details of what it had:
-bored .030, cast flat top (4 brow pistons). Bore = 3.905"
-.010/.010 (3" stroke) steel crank, factory rods/bolts.
- rebuilt (but not planed) 60cc power pack heads with factory 1.72/1.5 valves (it was originally a 195hp/2-bbl engine, but I guess the put PP heads on everything by '64).
- edelbrock performer cam (204/214 @ .050 lift 0.420 int./0.442 exh)/matching, roller time chain.
-edelbrock performer intake, quadrajet off of a '70's 350/untouched
-stock point distributor with Moroso wires and MSD blaster 2 coil.

It's not been run since fall of '94 and only had 4K miles on it, but it's been in storage since it was removed and I'm preparing a plan to convert the top end to vortec from a 305 (Heads/intake/TB/injector/ignition, ect) in preparation for the swap since I want to preserve the fuel injection. The 305 vortec heads are much better flowers than the power pack, + they have hardened seats and 1.84/1.5 valves, and more efficient 56cc chamber.

Despite this being a Pontiac forum, I am hoping that some of the members on here have some old school experience with 283's, what worked, what didn't, and their thoughts.

Is the vortec top end a good plan?

The S-10's an auto (4L60) with a 3:08 rear if that helps.

Thanks and yes, I am doing what I can to keep the Pontiac brand alive with my '09 G8 GT, although it's heart is standard GM, LS-engine fare.

Thanks in advance everyone!

[Cammer-6]

buy the swap book from JTR
its money well spent

[justincampbell]

I vaguely recall reading something on another site about bigger valve heads on 283s being bad news. That particular group indicated that you really didn't want to use anything with much bigger valves than your current power pack heads. I may be wrong, but it's something to consider. I hope the swap works out. 283s are great little engines.

[Cliff R]

The Vortec top end is a good plan, but only to get accessory bolt holes and the later/revised intake manifold bolt pattern to use the TBI top end.

The early Power Pack heads are excellent, and worked very well on 283 engines from that period. They had very small/efficient runners, small valves, and tiny combustion chambers, making them very well suited to the little 3" stroke 283's in low performance applications.

It wasn't uncommon at all to see them knocking down excellent fuel economy (some over 20mpg's) in full size Impala's with PG transmissions and low (numerical) axle ratios.

The 283 crank in the 327 block has always been one of my favorite small block Chevy engines. They LOVE to rev, and don't even really start sounding good till they get past 6000rpm's!.....Cliff

[salem1912]

Speaking of 283's one of our members had this for sale a few weeks ago; http://forums.maxperformanceinc.com/...&highlight=283

[Formulabruce]

Originally Posted by Cliff R

The 283 crank in the 327 block has always been one of my favorite small block Chevy engines. They LOVE to rev, and don't even really start sounding good till they get past 6000rpm's!.....Cliff

You speak of the Famous 302 Z-28 engine....... (4X3)

Have had 2, and your right after 6 grand the motor finally sounds like its "in sync' and just getting going..


I think you can get a vortec intake for a older style head now... Thats what I would do, and get some mystery oil in those bores!

[moparcolt]

I've done the swap into a 92 S-10. made my own mounts and used the short water pump from the early motor. the accessories on the front were the biggest pain, because the alternator in the S-10 is on the opposite side so the wire wouldn't reach to the drivers side.
any ways back to your question. The 305 heads should work fine. check your compression though going from the 64CC power pak heads to the 58cc 305 heads is going to up your compression a bit. you may have to run 92 octane gas? just check I m not sure on that.

The one thing I would make sure you do is get rid of those points, get a HEI or similar distributor, that's what I used.

are you using manifolds or headers? I used a set of shorty headers from sanderson! they worked real well.

The overdrive trans should help the 283 out a bit by giving it a better gear ratio on the bottom end, the 700R4 has a low 1st gear.

I've run the performer cam in a 307 which is similar to a 283 in a truck with a 3 speed and it worked real good. your torque converter should be a little looser than stock, this will really help. it will let the 283 spin a little to get it into it's power range, if you use a lock-up converter it will be very streetable with a looser converter, like 2500 stall or so! this will be the thing that makes or breaks how you are going to like the motor in the truck I think, if you load it up with too tight of a converter it will be a pig. you need to let it spin up a bit!

I have the book on S-10 conversions if you need any info I would be glad to let you borrow it. It didn't help me alot but I do this kind of thing enough that I already kind of knew what I was getting into.

Chris

[Danimal]

Thanks, Chris!

Good information and yes, having a modern 4 speed auto w/OD, with the deeper first gears, will be a night and day improvement compared to the 2 speed PG, especially given the ~1,000 lb less that the s-10 weighs, lol.

I'm imaging that the vortec 305's front accessories/serpentine system will bolt right onto the 283 with the 305's heads in place. I was warned that the my timing chain/cover won't work as the 305 vortec's had a reluctor ring on it, but I have yet to verify that.

I believe the 58cc chambers of the L30's heads will bump the compression of the 283 up from the 60cc PP heads, but I'll measure it and determine what gaskets to use to get as close to the 9.1:1 that the L30 had factory, maybe a .2-.3 points higher if I can.

As for ignition, I'll be using the 305's vortec distributor, but replacing the gear to work with the iron Performer flat tappet cam.

Headers are a sure thing, but I've yet to decide which style to get. I want to preserve the quieter exhaust, so I'll likely use 2 1/2 Y-pipe, 3" cat, and the 3" summit cat-back exhaust.

I'm planning to improve a bit on the the 220 net HP and 290 lb-ft of torque that the L30 305 put out.

Again, thank you for the input.

[Sirrotica]

Pontiac Dude has done V8 swaps in S10 with both a Pontiac and a chevy and said the Pontiac was easier to install, just some food for thought.