I dug out an old version of desktop dyno, actually forgot I had it.

I remember punching in a bunch of info in the past but figured Id do it again.

I used stock head flow.

400cfm efi/4bbl

dual plane

small headers with muffler.

the crane 500511 made the best average numbers with this setup vs mellings and isky and other crane camshafts.

but

the stock camshaft advanced 4 degrees (stock is retarded 4), was an extremely close second....negligible difference. I added an equivalent lift at the valve of using 1.7/1.75 rockers, minimal difference, the difference was in the upper rpms where most wouldnt see under normal driving conditions, the torque remained the same in the lower rpm using the higher ratio.


I couldnt find the specs on crower or comp cam @ .050..but Id say they are simillar to the others.


Anyone with a newer version of desktop dyno get simillar results?

 

Im having brain freeze.


When I tinker with this desktop dyno, when I punch in the camspecs, and set the advance to 8, it loses overall power over advancing it 4.

My question, and something Im still puzzed about, is where the 4 degree retard is, cam or cam gears?

On this simulation program, the ideal specs are as follows:

IVO(BTDC)-18 IVC(ABDC)30 IVO -14 IVC 26
EVO(BBDC)22 EVC(ATDC)-10 EVO 26 EVC -14
ICA(ATDC)114 ECA(BTDC)106 ICA 110 ECA 110

int duration 192
exh duration 192
timing@advance 4


Does this reflect, stock cam, adjustable gear set, set to four advance or eight (given camshaft is ground correctly)? Im thinking four, basically taking the 4 retard built into the camshaft out and basically installing the camshaft "straight up"..yea, nay?


Its suprising just how well the stock cam advanced 4 compared to the other aftermarket camshafts. I like the idea of a modified stock engine, so advancing the timing a little is right up my alley.







This question is aimed at more experienced engine builders, what would you consider a safe cylinder wall thickness in the 300? If you see things the way I do, you might be suprised just how much of an over bore you can achieve with these engines.

 

MH, query the "figures"topic over on the Ford Six forum. IIRC, Bill has most of your questions covered someplace in it.

 

http://www.compcams.com/technical/Ca.../56-61_230.pdf

Comp specs are on that page.

IIRC Col Flashman has a 60 over on his engine.

Probably have to use "FIGURES" in all caps to find Bill's thread on FSP.

 

DD2K sucks on the 300, and is marginally accurate on other engines. I've had it spit out numbers within 1% of what the engine actually did on several occasions, and I've had it be over 200 hp off on others and those are both small block Chevy's. The further you wander from the typical SBC the more questionable the results become.

 

I cant get the comp cams pdf file to open, my reader works, I just installed it yesterday to open up crowers camshaft files.

I read the fordsix articles on the camshaft retard when it came up...in the cam is what they said.
I saw the FIGURES thread yesterday, what program was he using?


Reason I ask about the cylinder wall thickness...
someone once suggest to me that they sonic tested a 300 block...
in their mind, 4.125 was safely obtainable. Can you imagine 320 on a stock stroke.


I used to have all the 300 cam specs in this program, then I realize when I uploaded it to my email due to needed computer repair, they be gone when I re-opened it.

 

when i use DD2K i can get within 1 hp and 2 torque with stock specs. i have found the 503901/5 cam mimics the stock power band quite impressivly and raises useable rpm by 500. add in headers and the torque curve is flat as can be.

if u want u can try to send u all the DD2K files i have on the 300.

 

They ain't that thick! I've been looking into resleeving one with 400 sbc sleeves so I could build a 351 stroker, but other than that it won't go that big.

 

Really....the fella that told me....isnt exactly uncredible....I thought it was alot though. You know which year block you examined?



Sure.

 

One of them came out of a 74 F-100, don't know if it was original or not, the other two are EFI. For a block with a bore center of the 302 and 300 you have to siamese the cylinders to safely go to a 4.125" bore. They aren't even close to each other on a stock block. I have no doubt that you can more them to 4.125" and put the engine together, but it would be a miracle if it ran properly. Most blocks are very questionable at .060 over. There might be a HD truck block out there that will take it, but I doubt you'll find a standard block that will.

 

i wonder how much the SVO block can handle and dammit, where can i get one.

 

At .60 over I've never had any problems (so far so good) I was toying with the idea of tearin it back down and going .70 over so I could use .20 over 390 flat top pistons. My heart jumped when you said you could go all the way to .125 over and all I wanted was another .10, but now I'm still a little weary. I have a block outta a 74 and 78, the one in my truck is an 86, but I always assumed they were all the same (blockwise). I did hear you could get .80 over pistons at the time I was gettin my .60 over pistons but the price jump was nuts. I may just end up taking another head I have and porting it out, using the bigger valves, chevy rockers and shaving it way down to put me at about 10:1 comp. How do you advance the cam on the 300? You'd have to fab a speacial gear wouldn't you?

 

For the record, Im not saying you can bore it out .125, I guess it depends on what you consider safe wall thickness, which is why I asked that first. I just know a fella sonic tested a block and based on what he and his buddies considered safe wall thickness for the SBF, they saw it in their block. It may have been a fluke I dont know. If you know a engine builder with the right toys, maybe you could test a few and determine a safe max overbore.

It would seem, in a dream world, theres some torque to be had if you can stick a big *** piston on top that 3.98 stroke. Usually an overbore is for cleanup as power gain is minimal but I think in this scenario, theys power to be made.




You advance the timing with an adjustable gear set, cloyes sells them.




I figued a hypothetical, using the stroker crank throw from the crank clifford used to sell, along with a hypothetical 4.125 bore, it put the old inline right around 350 cubes, talk about crazy low end torque.





Ill have to ask the fella which block he used to test out....maybe theres a mexican block for the 300's like the 302's

 

Comp 252H @50 206-206 .433-.433 110*

260H @50 212-212 .447-.447 110*

268H @50 218-218 .456-.456 110*

 

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300/49 bored 30 over (304 cid?)
Comp Cam 260H grind & lifter/spring kit
Intake/Exhaust Duration @ 050 212
Intake/Exhaust Lift 0.447
Lobe Seperation 110
Stock rockers
.010 off head & block, Federal Mogul 8.3 hyper pistons W/coated skirts (Est. 8.65 cr)
3 angle valve job W/30 degree back-cut
Holley 0-1848 4v, vac secondaries rated @465 cfm
K & N Extreme air filter
Offy DP manifold, P/P with port match head/manifolds
EFI exhaust singled out through high-flow Cat & generic turbo muffler 2 1/2" throughout.
Mallory HyFire 6a, MSD 2 Blaster, Stock plugs gapped @ 50
Recurved DS2 dizzy

With those specs he showed 208 hp @ 4500 rpm and 299 tq at 3000 rpm
With 450 cfm carb 214 282
With 600 cfm carb 222 291
With Chebby Rockers 211 300 on the 465 cfm carb. I thought it a bit odd that the smaller 450 cfm carb showed more hp and less torque than the larger 465 cfm carb.

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