Street Rodder is doing a Crate Engine Build up and started with a 290 HP Crate. They changed cams right away, then put on Edlebrock Heads. It made decent power but why would you spend a extra 4-500 dollars to get the 290 motor if your going to change heads and Cam right away. Am I missing something ?
. My question exactly... and more... why buy a crate engine that you have to throw 3/4's of it away...?
. As far as I know, 260 and 290 HP are same Mexico 350" with dished pistons and big 76cc chamber heads... "8.5:1" (actually ~7.6:1) compression ratio... base 194/202 durations, .390"/.410" lift cam for 260 and 224/224 durations, .450"/.460" lift cam for 290 HP... too low and way too low compression ratio for those cams...
. I'd suggest having a short block rebuilt with flat top hyperute pistons and cam of choice and add some good flowing heads like these for best bang for the buck... like up to 450 HP depending on cam...
The cam is the only difference adding approx $400 to $500 to the price tag & the cam they use is poor suited to the engine & it's compression ratio.For only slightly more,you can buy the L31 Vortec & have more power,better heads,roller lifter/cam setup.W pc rear seal.It just makes no sense.
The camshaft, the 290 has a big cam combined with the same low compression of the 260 horse engine. That of course reduces bottom end torque against the 260 engine and increases top end horsepower at the expense of a bit more fuel consumption to cover the loss of efficency with a "big" cam running against insufficient compression.
So you're not missing anything. The basic 260 horse engine is a good deal especilly if you hunt for a discounted price which doesn't take too much energy. Then put a decent cam in it, put some good heads on it and you're looking at something more like 350-370 hp for the same money as the 290 horse engine.
Here's a cost estimate I put together a while back on this subject:
Low cost 350 using the Goodwrench 10067353 260 hp long block
Basic engine is 4 bolt main, 2 piece rear seal, nodular iron crank, PM rods, hyper pistons, mild cam, low compression heads. Cost as of 02/10/2015 is $1510 from Summit. This is the same basic engine as the hotter cammed 290 horse version that otherwise uses the 222/222 350 horse 350 engine cam but these engines use 8 to 1 compression and poor burning heads.
The answer in both cases is replace the heads with modern fast burn chambers and higher compression. In the case of the 260 HP engine it also need the hotter cam. The 290 engine P/N 12499529 is $2073 long block equipped as the above 10067353.
- 260 version hop up
Long block $1510
Summit Vortec heads increase compression to 9.2 $679 or with Speedway FloTek heads at $740
Summit K100132 cam @222/222; .450/.460 $134
Total is $2323 with Summit iron Vortec heads or is $2384 with the Aluminum FloTek head
This easily makes 350 horse engine with an Edlebrock Performer RPM intake and 750 cfm Holley
- 290 version hop up
Long block $2073
Summit Vortec heads increase compression to 9.2 $679
Total is $2752 with the Summit iron Vortec or is $2813 with the Aluminum FloTek head.
This is equivalent to the hopped up 10067353 above but costs $429 more for no difference in parts.
- Analysis
In comparison the 350 HO with GM iron Vortec heads and the 222/222 cam is $2829 where starting with the 260 hp version is $506 less than the 350 HO for equivalent to 20 hp more power.
( Actually, about every hot rod type magazine has already done some version of that same article years ago and they're available on line... do a search for GoodWrench Build... (was called a TargetMaster engine earlier) )
. Notice by end of Part One of that article, the engine is still making less HP and less torque than a stock 1968 L46 350 HP 350" engine or 1970 LT1 360 HP 350" engine...
I did see that. It seemed to me they went a long way around to gain 35-45 HP. For what it would cost us to buy and change I would go ahead and buy a Complete 330 HP 383 for$3395
I wonder why GM doesn't sell the 260 HP version as a short block... seems a waste to buy the long block, then replace the heads right out of the crate?
I think GM does.At least they did awhile back.Haven't ckd lately,but,IIRC,the short block,minus cam & lifters was $799 thru GM.The L31 shortblock was approx $1100.It may not be offered anymore.
Best I can tell GM got out of the new short block business. The crate engines the OP refers to are built on the 12605117 short block, haven't seen these for sale in a while. Pace lists it as no longer available. That does leave the OP a range of rebuilder short blocks. To which it's likey the cost will not include the pan, timing cover, oil pump, camshaft, timing set lifters, etc., and related fastners gaskets and seals that usually are present on a long block.
Still it goes go back to if my choices were the 260 hp or 290 hp long block which would I pick? It would be the 260 LB and build from there with a flat tappet cam for which I have new lifters for from the LB. With older long ramp cams like that which comes in the 290 LB unusual wear on lobes and lifters is not much of a problem as it is with shorter ramped faster lifting aftermarket cams. So using good diesel oil and a ZDDP additive should give satisfactory wear. Then sell the original heads and cam on Ebay to recapture some of the cost of the LB.
This is a perfect example of why I let almost all my magazine subscriptions run out years ago. I found myself questioning the credentials of the writers when they did stupid stuff like this. They could have built up a short block, or bought a short block. But to start with spending more money, and then toss half of what they bought is just stupidity.
I agree for less than $1500 you could build a real good short block with Quality pieces. Then you would have a good base for the heads and cam to really make HP.
It has been awhile since I saw the shortblocks for sale.They were available thru GM Parts Depot,but,I don't see any listed now.I agree tho,the 260 would be a better buy.Your basically paying almost $500 for a flat tappet cam when purchasing the 290.
. I think the really nice short block for the ZZX-ZZ4 engines used to be available... was a better starting point for a performance build...
. There are numerous rebuilders who will sell you a rebuilt shortblock for a reasonable price and many will use the parts you spec. out for slight additional cost...
. One of the magazines did a build up on a rebuilt 350 shortblock with dished pistons from Coast Engines... in the next issue, they admitted they didn't realize they could have had it with flat top pistons for the same price and much better power results... (and prolly choice of compression heights, as well)
. About an identical wimpy 350" engine was available in vehicles from 1971 to 1995... in boats even later... and still available new from GM... most of these crate engines just get bought and tossed in a vehicle... so there are millions of them out there and a lot of interest yet in building them up... but to buy one with the intention of immediately building it up, of course, makes no sense...
.
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Hot Rod Forum
2.2M posts
175.7K members
Since 2001
A forum community dedicated to hot rod owners and enthusiasts. Come join the discussion about restoration, builds, performance, modifications, classifieds, troubleshooting, maintenance, and more!