He didn't mention that the Cooper Cobras on the YJ8 Corvette wheels are brand new.
Martin
Martin
CK5
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1970 Chevelle Malibu "400" Clone
- Thread starter 80' 427
- Start date
Those.
Martin
Martin
absolutely. 289s are some if the thickest but the early to mid 70s are thicker than the late 70s to 80-90. Since the 959 is already .060, if it isn't thick enough to go .100 it is probably iron. I would rather use it up. I compared a 73 289 to a 85 445 once, things like the starter pad thickness , around the lifters etc were noticeably thicker. Still my Camaro has a .060 88 445 block making 1050hp with no problems so even the light blocks are still reasonably thick.
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Of all the rims shown on your car, I like these the best.
Ordered AFR 265 heads for the 520 build. Said they were in stock. Shows current delievry on 11-1-21. Not sure if I should cancel or just wait. I realized they were hard to come by but "2 left in stock" is misleading.
Zim, A few reasons. I looked at larger heads, but these flow more down low than nearly every head, and even up top they still flow pretty great. Below is the a comparison with a 305 rectangle port. Yes at .600 and .650 the 305 flows more, but look at the flow advantages below .600". Also, look at the exhaust flow vs the intake flow. Flowing similar with a smaller port should make the streetability awesome. Plus 335-340cfm is enough to make 670-680hp which should be plenty for a street engine and the torque should be eye bleeding.
Finally they are some of the cheapest heads they make. The goal of this engine is to be a great street engine that will lug along at idle in first gear and pull like a freight train to 5500 or so. I also want it to look stockish with a dual plane and all will be orange.
Guys are using these on 496s and are making awesome budget power.
Finally they are some of the cheapest heads they make. The goal of this engine is to be a great street engine that will lug along at idle in first gear and pull like a freight train to 5500 or so. I also want it to look stockish with a dual plane and all will be orange.
| 265cc w/ 100% CNC Chamber Flow Chart | |||||||
| .200 | .300 | .400 | .500 | .550 | .600 | .650 | |
| Int | 164 | 236 | 291 | 326 | 330 | 335 | 340 |
| Exh | 135 | 190 | 230 | 258 | 265 | 274 | 280 |
| 305cc w/ 100% CNC Chamber Flow Chart | ||||||
| .200 | .300 | .400 | .500 | .600 | .650 | |
| Int | 154 | 225 | 280 | 316 | 345 | 362 |
| Exh | 133 | 187 | 223 | 249 | 259 | 264 |
Guys are using these on 496s and are making awesome budget power.
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Sonic checked the block after work. I put on the numbers in the wrong location so the top of the page it actually the top of the cylinder (closest to the lifter valley) should go .040 more. Plenty thick on the thrust sides.
I know right! Probably the last overbore but meh, it is a 2 bolt '75 pickup block.
I hope it will work great. The other thing is a mildish street rollers are almost all under .650 lift so the flow at those higher lifts doesn't really help. It may be silly to go this big but so far the cost is the same as a 506 build (.100 over 454 with 4.25 stroke crank).
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Yesterday the head ship date changed to 11/29/21, now it says "ready to ship". If they come next week I will be super happy that I left the order alone and didn't cancel. Now to find a roller cam somewhere. Probably going to have my cam made on a gen 6 core, simply because I prefer the retention plate and like that the timing gear rubs on the plate and not the block. My Camaro 427 had a gear eat the front of the block and I had to have it repaired and add a thrust roller bearing.
That's how my heads went. 3 month lead time, showed up 2 weeks later.
I am really have an time trying to find and or decide on a camshaft. Of course a 520 with compression will turn a hot 454 cam into a RV cam. Still I it needs to pull air and idle in first gear with 3.55 rear axle so I am trying to find the happy medium. Not sure if I should be in the 23?/24? or the 24?/2(4-5) camshafts. It probably can stand to loose a bit of torque for some more top end.
