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351 Hp/value estimate

  • Thread starter Thread starter Randy'65
  • Start date Start date Jun 9, 2008
R

Randy'65

Founding Member
Feb 1, 2000
352
0
17
Richmond, VA
Jun 9, 2008
#1
  • Jun 9, 2008
  • #1
A buddy of mines brother is selling a 351W that he was building to put in his truck. Engine originally came out of a boat, and it's thought to be an 83-88 era block. It's got:
351 block bored .030 over, decked, dipped, and magnafluxed
Hypereutectic pistons, 9-1/2:1 compression
crank work done
mild cam installed
aluminum intake (sounds like it might be an off brand, not sure if single or dual plane, he just said it was similar to an edelbrock - name was like two letters or something)
CI heads, ported, polished, oversized valves, emission ports plugged
Edelbrock carb, 600 cfm

What do you think the horsepower would be? He's guessing 350-375, but I think that's pretty conservative

What do you think it's worth?

What other questions should I ask? I'm really not sure what else it would take to go in my '65. I've got a T-10 4speed behind the original 289 block, and an 8 in. rear. Which would break first?
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Jun 9, 2008
#2
  • Jun 9, 2008
  • #2
Randy'65 said:
A buddy of mines brother is selling a 351W that he was building to put in his truck. Engine originally came out of a boat, and it's thought to be an 83-88 era block. It's got:
351 block bored .030 over, decked, dipped, and magnafluxed
Hypereutectic pistons, 9-1/2:1 compression
crank work done
mild cam installed
aluminum intake (sounds like it might be an off brand, not sure if single or dual plane, he just said it was similar to an edelbrock - name was like two letters or something)
CI heads, ported, polished, oversized valves, emission ports plugged
Edelbrock carb, 600 cfm

What do you think the horsepower would be? He's guessing 350-375, but I think that's pretty conservative

What do you think it's worth?

What other questions should I ask? I'm really not sure what else it would take to go in my '65. I've got a T-10 4speed behind the original 289 block, and an 8 in. rear. Which would break first?
Click to expand...

Without better information on the cam, intake and heads its tough to say. CI (cast iron?) heads... are those stockers or a brand I'm not recognizing (possible, heh)? Try to get some specs on the cam.

If its basically a 351 with a performer intake, performer cam, and ported stock heads 300 hp might be pushing it. If the intake and cam are more aggressive, and especially if the heads are aftermarket and/or the port job is very aggressive, his guess might be accurate or even slightly conservative. I doubt its going to be substantially more than 375 hp in any event.

Also keep in mind 'crank work done' doesnt' mean a whole lot... could mean that the shop reconditioned the stock crank/rods or that they were replaced with high performance aftermarket parts. The fact that the pistons are hypereutectic suggests the former.
 

fvike

Member
Aug 24, 2004
335
0
16
Mosjøen, Norway
Jun 9, 2008
#3
  • Jun 9, 2008
  • #3
Wouldn't a '83-'88 era block have a roller camshaft? If so, it's a plus.
 
M

mr-fixit

Founding Member
Jul 19, 1999
466
0
17
Malvern,Pa.
Jun 9, 2008
#4
  • Jun 9, 2008
  • #4
fvike said:
Wouldn't a '83-'88 era block have a roller camshaft? If so, it's a plus.
Click to expand...

The 351 roller block came out in 94
 

Hack

15 Year Member
Mar 23, 2004
1,945
13
69
Minneapolis
Jun 10, 2008
#5
  • Jun 10, 2008
  • #5
What's it worth? The problem with selling a used engine is that there's a lot of trust involved. If a reputable shop did the work and there are receipts and the engine is covered by a warranty it's worth more than if not. It's all about if you can find someone willing to pay. I would think it's not worth more than $1,000, probably $500 or a little more. When I see a relatively fresh engine for sale, all kinds of alarms go off in my head. Something is wrong with the engine and he's trying to dump it - that's the first thing I think.

With stock cast iron heads it could make decent power if the porting was done by someone who's good at it and all the components are well matched... maybe as much as 350 if everything is done right. I expect it's probably less than 1 hp per cube unless an expert built it. Were the heads tested on a flow bench? What are the runner volumes? What I'm getting at is does he have positive proof that the engine is good or worth buying? edit. He should also have part numbers for every component, know what the compression ratio is, etc.
 
R

Randy'65

Founding Member
Feb 1, 2000
352
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17
Richmond, VA
Jun 10, 2008
#6
  • Jun 10, 2008
  • #6
Compression ratio tested at 9.5:1, work done by local machine shops that have been in business for some time. I personally don't have any experience with them. He says he has about $2200 in it, he's going to craigslist it for $1800. He's just in a pinch and is selling the truck that he was building it for. It's a non roller block, and yes, the CI heads are the cast irons stockers that have been ported/polished with oversized valves installed. And his little brother works for me, don't think he'd be looking to screw me;-)
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Jun 10, 2008
#7
  • Jun 10, 2008
  • #7
Randy'65 said:
Compression ratio tested at 9.5:1, work done by local machine shops that have been in business for some time. I personally don't have any experience with them. He says he has about $2200 in it, he's going to craigslist it for $1800. He's just in a pinch and is selling the truck that he was building it for. It's a non roller block, and yes, the CI heads are the cast irons stockers that have been ported/polished with oversized valves installed. And his little brother works for me, don't think he'd be looking to screw me;-)
Click to expand...


Doesn't sound like its worth $1800. As said before, you're probably looking at somethign between $500 to $1000.
 
R

Randy'65

Founding Member
Feb 1, 2000
352
0
17
Richmond, VA
Jun 10, 2008
#8
  • Jun 10, 2008
  • #8
Wow. How much was your Edelbrock 600 carb? I forgot to mention the included MSD box, seems like those two things alone would be $500 in new condition. And how much does it cost to get a block dipped and magnafluxed?
 

SadbutTrue

Founding Member
May 1, 2002
2,390
4
49
Granada Hills, California
Jun 10, 2008
#9
  • Jun 10, 2008
  • #9
Randy'65 said:
Wow. How much was your Edelbrock 600 carb? I forgot to mention the included MSD box, seems like those two things alone would be $500 in new condition. And how much does it cost to get a block dipped and magnafluxed?
Click to expand...

Used Edelbrock 600s will go for 150 on ebay... MSDs... don't know, maybe another $100 (remember used is used, these things haven't changed in decades).

You would definitely be advised (or your friend) to try and sell the MSD and Edelbrock carbs seperate (if you need to sell the engine as a complete unit, get a cheap rebuildable holley for $20-30 off ebay and sell it with that). The engine will probably go for about the same, and you'd have a few hundred extra in your pocket from the other stuff.

Engines (and cars in general) are definitely worth more in pieces than together, especially parts that detach easily like that. The rest of the engine will probably reach its optimal value complete (cams, ported stock heads, etc.. aren't the types of things that command great $$ individually on ebay but if advertised as part of a strong-running engine can).

For comparison, I was looking at a recently rebuilt 331 stroker a few months ago. Similar to what your friend was selling... it had hypereutectic pistons, 10:1, ported stock heads, a compcams 280h roller cam, performer intake (boo), etc. Probably made 350 horsepower, or could have if healthy.

But since it wasn't built with the real topend goodies (forged crank/rods/pistons, more elaborate intake, didn't have aluminum heads, etc).. it basically seemed to be a budget performance build that some dude had thrown together for cheap. I brought it up on here thinkign it was a great deal (he was asking $1500) and everyone told me to shy away. The message was if you're buying a used engine from someone you don't know, it better have high-end parts in it or there's far too high a chance you're getting dead weight. I decided it'd be better to keep my 351w and spend the money on the aluminum heads/cam/etc I wanted and knew would work well.
 
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