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Alright I want to know something. Lets say I wanted a built 351 no more than .30 over, and not stroked. What is the maximum amount of torque it can have if my peak is between 2500 and 3500 RPM?
Whatever you think man. Hypathetical situation. So I will say Carburated in a truck. I'm just saying what is the maximun torque on a built up 351 with the torque peak at no lower than 2500 RPM, and no higher than 3500 RPM. The motor can be built up as much as possible as long as torque peak is no more than 3500 RPM, and the motor is not stroked. This is one of those theoretical think tank questions, because I'm curious, bored, and I know some people here will want to talk about it.
A 10:1 357 with good heads(AFR 185), RV cam, 650cfm 4bbl, and longtubes will make over 400 ft/lbs from 2000rpm and up. A Dyno sim of this combo reports peaks of 422TQ at 3500rpm and 362hp at 5000rpm.
Thats pretty impressive, better than I was thinking. Does it get any better, can you get 450-500 at 3500 RPM without stroking.
you would be hard pressed,
I think around 380-400 ft at 32-3500 if the peak power was say 320ish at 5000rpm.
As a rule of thumb,the more power an engine makes they higher the power band moves up. The best way to make low rpm torque is cubic inches, best in your questions, great heads with a generous amount of lift with fast lobes and mild duration. Headers, duals 2 inch pipe.
A lot of things are possible depending on how much money you have to spend. Supercharge it and a will make 500+ pdft no worries. Normally aspirated, maybe if you pumped the compression up to 13.1. Good luck finding gas you could run it on though.
But you could easily get ~400+ pdft from 2,000 - 5,000 rpm and spin it to 7,000 if you wanted to with the right parts. Easily being ~$4-10,000...
Stock 351w roller short block w/flat top pistons - ~$1,700
AFR 165 heads - $1,500
Performer RPM manifold, 650 cfm carb, headers, exhaust, dizzy, etc. - ~$1,000
A Comp XE256HR cam would be another $250 if you wanted.
Add $1-3K for a stroker short block and get AFR 185 heads.
So to make 400 TQ from low rpm on up I am going to have to spend at least $3k on my engine, and more likley around $5k. I thought you could make a lot more power for much less money with a 351W.
So to make 400 TQ from low rpm on up I am going to have to spend at least $3k on my engine, .
Yes that's about right.. buying all new parts and paying advertised prices for everything. All this stuff is available used to so you could potentially do it for half as much.
Originally Posted by dwrestle
I thought you could make a lot more power for much less money with a 351W.
The motor can make lots more power.. it just won't be at 3500rpm. And there are lots of heads available that don't cost $1500 a pair though they don't all perform the same, but good options start at about $600 for CNC ported E7's for example.
Exactly. What are you building, a boat engine? Building an engine around a desired powerband is one thing, saying I only want to look at the 1,000 rpm range from 2,500 to 3,500 is another.
Maybe this article on building a 400hp 302 for ~$1,000 will help too.