Dynra Rockets

I will need to build another engine sometime in the distant future. In my quest to save some weight I am thinking of using a 207 block as internet lore says they weigh about 14-15 lbs lighter than my 1969 vintage SBC block but is still a "high nickel content" block. GM introduced "light weight casting" SBC1 blocks in 1980 and used them though 1986 when the roller lifter blocks came out in 1987 (there might be some later truck uses too)

It will not be built to more than 350 crank hp. Other than the dipstick on the other side, any downsides to this plan? Maybe just jump right to a roller block?

Internet searching has been inconclusive. Any other SBC1 "light weight casting" blocks to consider for weight loss?

R

L88Plus

Find a roller block with fuel pump drilled. Or build with the -207 block and cringe every time you stand on it because waaaay back in the cobwebbed recesses of your mind, a little voice screams "but it's a lightweight block!". Peace of mind is worth a lot, particularly when thousands of dollars are invested.

jackson

https://www.ebay.com/itm/GM-OEM-NEW-...p2056016.l4276

read the discounts & details … today it's $1730 delivered … brand new not reman … roller lifters-cam, iron Vortec heads, 4-bolt main. Pay local machine shop $100 to finish fuel pump mount. Swap to bigger cam & springs under $500 to make 350-400 crank hp. You can't build a motor for that$. And this is all new not rebuilt.

FYI … those trucks' advertised with 245-255 horsepower … same motor as above but with varied ECM tuning per application

Dynra Rockets

Appreciate the suggestion. For me its less about cost and more about the joy of building it. Also, one of my primary goals is to reduce weight so an iron head engine is not something I will consider. I will however look more closely at the short block version of this.

cv67

Think olds diesels in the 80s had some type of lighter block not sure about GM? Interesting

Dynra Rockets

As part of the general weight loss program starting with the 1980 Corvette, Chevy also redesigned the SBC block to be lighter. The -207 was generally in Corvettes and were classic SBC1 design (two piece rear seal, flat tappet lifters, etc) and were made from 1980 through 1985 for the Corvette. According to www searches it is about 14-15lbs lighter than a comparable earlier block castings.

jackson

understood … although someone else w/ AL heads could easily sell the desirable new iron Vortecs, valve covers etc for $400-$600

fyi … the suggested motor has -880 block

Dynra Rockets

I hear ya, but the -207 was also in a 1985 Corvette and lots of people punish those regularly without incident. I personally know of a guy with a 400+ hp naturally aspirated 85 using the stock block. I'm still researching and looking into it. Just wondering if anyone can confirm the 14-15 lb weight loss of the -207?

Buccaneer

Nothing wrong with a 207 block IMO. I ran one for 12 years as a 385 with no issues until (by my fault) I broke two hypereutectic pistons and damaged the block and didn't want to bore it another .020 to .060 over to repair it and have it become a heater and found a nice 010 block with my new current .030 over 383. If you are concerned, get a roller block or SHP etc...

80-Vette

Is 14 -15 pounds worth it to you? If you want to go with a lightweight block do an LSx upgrade you would be so much better off.

Fredtoo

Go big, or go home

https://www.chevrolet.com/performanc...um-race-blocks

sstonebreaker

How much of your old stuff are you planning to reuse? The LS blocks are 110 lbs lighter than the SBC roller blocks, never mind a piddling 15 lbs. Plus they'll support way more horsepower.

Jebbysan

Not sure who started the "high nickle content" block deal, but it is absolute BS.
And if ANY block is lighter than the old 010 block.......there is a reason why......throw it in the trash.

Jebby

Dynra Rockets

In short, yes. My short block will eventually need to be replaced anyway so might as well look for a lighter one. A quick search on FB marketplace shows there are several in the $75 range. $75 for 14# drop is about $5/lb, I have paid a lot more than that when I replaced other failed parts... $500 for Wilwood aluminum brake calipers with a 26# drop, $75 for an aluminum master cylinder when it died for a 5# drop, etc.

I have not ruled out a LSx swap. I'm just researching at this point, so far my spend is about an hour sending a few electrons through the internet. I would prefer to keep the SBC accessories and ancillary items I already have so that leans me more towards a SBC solution. The internet wisdom is all over the place but generally says my 618 bare block weighs around 175-180lbs and a 207 bare block weighs around 155-160 lbs.

I am just collecting data at this point so anyone that can verify weights would be welcomed.

R

Dynra Rockets

Drool. Love it, but afraid out of my price range though. :-)