Thread: 305 pushin 480HP?

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I'm in the proccess of a 383 build and there's a 305 in the car so just out of curiosity I cam quested it and it's producing unbelivable specs. I added HP pocket port stock valve heads, 750 cfm carb, a single plane max flow intake and it's making 10.5/1comp. with a 237 483 cam. Stock stroke bore and rods Can this be true? Has anybody used the program with accuall results? With a little cam tweaking I was getting 518 I think was the top end HP. I couldn't get these numbers on my 383 with out extensive bottom end $ not to mention the heads. I wouldn't put money it would last long with out replacing every part with new but still that's a damn site cheaper than where I'm heading. My name says it all I don't care how i get there. Here's the 305 in the car now.


http://i470.photobucket.com/albums/r...t/PIC_0034.jpg

If I could get those numers out of that thing I would never shut my mouth about it at the track. If I ever get there again.

you can always build a 335 its a 305 with a 400 crank ju stlike a 350. because the 305 has the same stroke its ju stlike making a 383 just with a smaller bore

Sounds kinda crazy to me, this is what my desk top dyno says on the link below.

http://i154.photobucket.com/albums/s...g?t=1223119682

Those are the exact specs I pun on camquest Mooney, with of coarse a drastic differance in results. Where did you get that program? And have you used it with real world results?

I have a 350 block that's in great shape I bet not 10 k mi. on it, and the 305 is in the car now, so I don't want to pull it. I Like what the camquest told me But I don't belive it . Mooneys results are more realistic.

Does anyone know about nickel content? I used to help my uncle build motors when I was, well-from 15 to 18 and he wouldn't build a race motor with out the number 10 in the block numbers, stating "If it doesn't have nickel in it it wont last" Then I read from David Vizard it has to have 10 or 20 and some other confusing things. Can any body help me with this?

camquest is free software, where as desktop dyno is a pay for program. $50 I think, so it has more development and accuracy

Originally Posted by like2gofast

Those are the exact specs I pun on camquest Mooney, with of coarse a drastic differance in results. Where did you get that program? And have you used it with real world results?

I used the desktop dyno, its a purchased program. I find it to be a little on the high side on the #s, but it gives you a real close ballpark for sure. And also tells you if you are going in the right direction with your ideas or not.

as far as building a race motor from a 305 baseline, I personally would not and would throw my money into that 350. I always considered 305's to be a good reliable cruising motor with a stroke that is hard to make real strong power from like you are wanting.

I'm using DynoSim Pro Tools and so far it looks to be low by about 2 1/2%. If I track 400, actual from dyno results is 410. This software was regularly $250, but is currently on sale for 99 bucks. I'm using 0.006" tappet lift for the seat-to-seat figures, so maybe if I stretched it out a couple of degrees on each side to cover the seat to seat figures, I might be right on the money.

Mooneye hit the nail on the head. Even if the software is off a bit, it will tell you which way to go with changes. Like I said on another thread here, I picked up 55 ft/lbs of torque and 90 hp for a fellow on another forum with a manifold and header change.

Here's a 10.0:1 355 Chevy with AFR Street 180 heads, 750 carb on RPM intake, 1 3/4" headers and a 276*/282* hydraulic roller cam with 0.502"/0.510" lift....
rpm tq hp
2000 375 145
2500 380 180
3000 410 235
3500 450 300
4000 480 360
4500 500 430
5000 500 470
5500 485 505
6000 450 515
6500 410 510
7000 360 485

So, it's not really that big of a deal to make 500 hp with a SBC if you use the right combination of parts. Further tweaking this combo by retarding cam timing by 3* resulted in 525 hp. Using a 2800-3000 stall converter and a rear gear around 3.90-4.10 would make this a good, strong street combination in my opinion. Engineering the squish to 0.035" to 0.045" should allow the use of pump gas and fully optimized ignition timing with no problems.

Like mooneye said, there's nothing wrong with a 305 as a cruising motor, but if you're going to try to move up to some serious horsepower, at least start with a 355 or bigger. The 305's have that tiny little 3.736" bore which precludes using heads with large valves. The largest valves you can get in there will still be shrouded next to the bore.

Yeah tech they're running a special on the program you suggested, so all I have to do now is wait for it. Thanks
I was kndq leary of that softwear anyway, but I'm always like that with free stuff.
So nothing on the nickel content scenario? Sorry guys I havn't built a motor in a while and my brain is kinda worn out, just on one side though so it wabbles. I can't remember a lot of stuff anymore like I used to could.

camquest is ment for cam choice, does not have to be accurate in the HP.. you just use it to match the peak hp in the RPM you want.. I used Desktop dyno to choose the cam for my Turbo 200 I6.. there was a 30% diffrence between diffrent cams.. I had a custom cam made that matched the 1 on desktop dyno I made that produced the best results

Not sure what block numbers are high nickel content. In the past, I have used mostly 010 blocks and they have worked out ok. Any subsequent builds I do on a SBC will start out with a Gen I roller block or short block. I don't know all the applications for these motors, but do know they were used in '89 to '93 Caprice and can be identified by block numbers 148, 548 and 638.

Starting with a roller block and one-piece seal just makes way more sense than spending big dough to convert an earlier flat tappet block to roller cam.

Now, I might change my mind if I came across a good 400 high-nickel block.....
http://albuquerque.craigslist.org/pts/867256265.html

I accually found out that 010 = 1% tin and 020 = 2% nickel. I have a 3970010 and the numbers 010 under and to the right of the timing chain cover indicate that it contains 10% tin that makes for a good casting as it allows the metal to flow adaquately and the nickel adds strength. I just recieved this information from a trustworthy source. Thanks for the craigs listing I'll check on that tommarow. Will I have to have work done on the lifter cyinders if I decide on a roller cam?

I don't think that's quite correct: almost all blocks you'll find to be in really good shape today will have "010" under the timing cover. If they haven't they're probably junk already. 010 means 1% nickel, 020 means 2% nickel. 010/020 means 1% tin, 2% nickel. The tin allows for better flowing and the iron will fill the mold better. Nickel adds hardness, so wear will be lower, especially on the cylinder walls. But nickel also makes for a more brittle block, so when power is going to go into the region where the block flexes noticeably, high nickel isn't an option. If you're thinking of doing a lot of drilling or grinding work on the block (oil galleys, boring, splayed caps, clearancing) remember: nickel is a tool killer. Some Motown blocks have as much as 5% nickel in them, but along with other additives to counteract the brittleness and there's no need to detail them.
If you're going for serious horsepower and longivity, go aftermarket. But up to 500hp you should be OK with a 1% nickel block, best bet would be to sonic test cylinder walls for equal thickness all round and put on splayed main caps. Then you're OK and cheap.
As I said, that is my information, without guarantee of correctness.
Max

hi just a slight side track but tech you have some figures for a 350 producing 500 horses and you suggest a stall of 2800 whan i look at the figs i see it makes 375 ilbs of torque at 2000 surely thats enough to launch quickly if you have a 2000 stall and wouldnt it make for a more street freindly ride? im not saying im right i just looked at the figs and put them in a drag race simulator and changing thew stall to 2000 made less than a tenth difference,surely undetectable in evryday street driving?
the reason im asking is i have a set up that will make good torque at 2000 but the cam card suggests a 3000 stall ??????