The engine is a 1959 283 with a 4.00" bore and a 3.75" stroke 4340 forged crank turned down to fit small mains (377 C.I.), with a 6.00" I beam rod, light-wieght dished forged Probe piston. Compression will be approximately 9.5:1. Quench will be optimized, the block was decked to .005", taking care not to hit the stampings.

The heads are 1959 #550 castings with 1.90" I and 1.60" E valves. The intake ports have been opened from 150cc to 170cc. The combustion chamber has been opened to 66cc. In stock trim, cut for the larger valves (before porting), the heads had a peak flow of 158 cfm I and 127 cfm E.

Ported, the flow is as follows:
Lift I E
.100 60 53
.200 125 103
.300 176 136
.400 204 156
.500 225 170
.600 229 188

The porter will be doing a little more work on the floor and in the short turn area and expects to gain a few more cfm.

The car will weigh about 3200 with me in it. The engine will be backed with an aluminum flywheel, a cast iron T-10, and a 3.25 Ford rear. Ultimately, I'll be running a wide ratio 4 spd or aftermarket 5 spd. The rear gearing will most likely fall in the 3.50-3.70 range. The headers are 1 5/8", with a 3" collector. I may add a 2.5" merge collector. The pipes will be 2.5", mandrel bent, with an H or X cross-over. The tails may have to be reduced, after the mufflers, to 2 1/4" or even possibly 2 1/8" to fit the bumper exits.

I'm leaning towards a solid flat tappet, but would consider a HR if there would be an appreciable difference. Also, I would prefer a cam with a "4/7" swap, on a 110 or 112 LC. I'd like to limit duration @ .050" to 240, less if it is a HR. The cam must provide 3" of vacuum during cranking, because I may run a modified Rochester FI that I have after engine break-in. The other induction choice would be a ported and highly modified factory dual quad intake. My goal is a streetable, stock-looking car that can break-in to the high 12s in the 1/4 mile.

I currently have an Engle EP22 cam, which was recommended to work with the FI. Its specs are .491" I/E, 274* adv I/E, 238* I/E @ .050", on a 110 LC. Any recommendations that will out-perform the existing cam, possibly one with a slightly larger intake lobe than exhaust? Thanks in advance.

I guess you wanted to go stealth b/c it would have been a whole lot easier on the little motor to have put it away and started with either a good 350 block or a 400.

And I do mouth about the old 4x4, 400", 283 motors of old too..

BTW, Sure, please look over at Isky's site at their solid cams b/c I figure either a Z-25 or a Z-27 should be about right for your application, imho.. (Or go with an Isky 280 Mega hy- cam..)

See if the Fel-pro #1094 .015" thick shim headgasket won't get you up to about 10 to 1 CR. b/c at 9.5, you will be a liitle on the low side, imho..

And lastly, please consider using a heavier fly wheel b/c it helps the launch from what guy's that have switched say.. If that is a concern??

pdq67

PDQ, thanks for the reply. The Z-25 cam is similar to the one I have, except it is on a 108 LC. I sent Isky a long email seeking a cam recommendation and am hoping for a response; they are only a few minutes from my work.

I decided to build the 283 after a 400 and a 350 that I had both needed block work (beyond boring). I think my engine is a good example of what some of these guys can do with their 283s and 307s. The 283/307 blocks could take a 350 or a 400 crank and make good torque. With similar mods, they should also be able to get some good numbers out of re-worked stock heads, if original appearance is important. Then, they could send their ekhaust and intake manifolds to Bryzynski for their re-work.

I know it would have been much cheaper to build an engine from a 350 or another 400 block. You got to admit though, there is a certain appeal to dumping the clutch and powershifting an original vette engine and trans... I grenaded the T-10 3 weeks after I got the car, and figure it won't be long before I do it again, at which point I'll step-up to a wide ratio 4 spd, or aftermarket 5 spd.

According to CHP's flow numbers, my heads outflow the 180 Iron Eagle castings with 2.02 and 1.60 valves, but I'm sure more power definitely could have been made with some aftermarket heads or even some similarly worked camel hump heads (larger valves and ports to begin with). However, I figured that since I was using the stock block, I would go ahead and try the stock heads.

If I had to do it over, I would have used Speed-O-Motive's small journal stroker kit. Also, I would have just bored my block .060" over and ordered a custom piston.

Anyways, does anyone have a cam recommendation... flat tappet or HR, 110-112* LC, "4/7" swap, and under 240* @ .050"? Thanks again, Wes

First, at 9.5 to 1 CR., a 268 to 272 cam will be best due to DCR thing, imho...

Second, it is small but the Little Duntov, -097 solid cam is a dandy but you might want to add 1.6 ratio rockers to up it's low lift??

I posted why I thought my nephew ended up with the stock, short block, except for a '67 forged Z-28 crank, 283 I ended up with and it is b/c it had a 308 duration hy- cam in it and 66 cc, -291 big valve heads along with stock, flat-top pistons and thick headgaskets.. SCR is like 8.1 or so and DCR about 5.2!!!!!!!

I advise making sure your DCR is right at 8, maybe 8.2??, by matching head chamber size, quench and piston type and down in the hole to achieve it..

AND please come back and tell us how she runs..

pdq67

The Isky cams PDQ mentioned look good to me. Your heads I/E flow ratio is good enough (I calculated 82% @ .500" lift) that the motor will make good power with a single pattern cam.

pdq67, I just got off the phone with Isky. They recommended a grind "S 652", and told me to ask for it on a 110 LC and they said I could get it on a "4/7" swap. With a 1.5 rocker, lift is .528, 270* adv, 242 @ .050". It's a single pattern cam, with some pretty intense ramps. With 1.6 rockers, the lift would be .563". Given my light weight valvetrain, the Isky rep didn't think there would be any problems with that cam. With my engine's 377 CI displacement, the lowend shouldn't be hurt too bad. Isky also said that the cam would meet the vacuum requirements of the Rochester FI, if I were to run it.

I'll be posting again once I have it running. The 'vette, since it is still driveable will have to wait until I get my Chevelle back on the road. I hope to complete the front end rebuild this weekend, and the 496 engine swap within one or two weeks from there. Hopefully, I'll be able to get the 'vette's new engine running by the first or second week of August, but there is a good chance I'll rebuild it's front end and do some detailing work before the swap, which will push it back a few weeks. Thanks again, Wes

Eric68, thank you for the reply. The Isky cams listed by pdq67 didn't look bad, but the Z-25 cam is quite similar to my existing Engle EP22, except it has a little less lift and it is on a 108LC, which wouldn't work with the FI. The Z-27 would probably be a little choppy for my application. I have run an Isky 280 Mega Cam in a 350 Chevy; it made great power, but the idle was a little choppier than I like.

I was surprised by the cam that Isky recommended, because the lobes seem pretty intense. It should build good torque and have a decent idle, though. I wasn't aware they were grinding SBC cams with so much lift for a given duration. I'll probably run lifters with an EDM hole if I use this cam.