JayZ28

I picked up CHP Oct issue and in there they had a 350 build up I was a little sceptical of. Basically it GM perf. parts HOT cam (218/228 @ .050 and 112 degrees sep.), vortec heads, vortec duel plane and 9.6:1 compression. After reading the engine buildup post below I was wondering if they would really get 400hp from it or it was just good reading.
Thanx

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speed is a good thing,
more speed is a better thing
86' SLOW LG4 bone stock
except for a K&N
Future Mods: T56
350-383
miniram

RB83L69

Looks pretty believable to me... think of that combo as basically a ZZ430 with inferior heads.

Also, don't forget that to build that motor, THEY DID NOT USE A SET OF VORTEC HEADS OUT OF THE BOX. They had to have done enough machine work to them that if they had been buying their machine work at real-world rates at the local speed shop like the rest of us, those heads would have cost as much as several other aftermarket ones that are considerably superior to the Vortecs. I haven't seen the article, so I don't know whether they changed out the crappy replacement truck valves for something good. In other words, that's a pretty typical magazine buildup article: it's designed to illustrate a particualr point, but does NOT represent a real-world best-choice scenario.

In order to do what they did, at a bare minimum they had to have had the valve guides cut down. In order for somebody out in reader land to build that and actually get any kind of long-term reliability out of it, the heads would also have to have screw-in studs installed, and the pockets cut for larger valve springs. Plus, to max them out, it would take $200 more for some undercut valves. So... you've got $450 of heads, plus $200 of valves, plus $75 of studs, plus $100 of springs, plus $80 of retainers, plus $15 of keepers, plus $40 of guide plates; plus machine work for guide cutting, stud pulling, milling, drilling, & tapping, which is all together about $175-$200. That means you now have a set of $450 heads that cost you a good $1100. Hmmm..... cheap heads aren't so cheap after all.

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"So many Mustangs, so little time..."
ICON Motorsports

jcb999

You can come close to that hp using a comp XE268 cam and vortecs. No guide problems

Vader

You can make almost 425HP with a 355 and a .447"/.447" lift cam. You need to consider the valve sizes and port design, not just the lobe lift.

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Later,
Vader
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"Click - Click - BOOM!"
Adobe Acrobat Reader

94-6spd

I have a set of vortec heads that have all of the same things done to them as the article states. Screw in studs, guide plates, 5 angle valve job, back cut valves 30 degrees, and they're ported. They were still inexpensive compared to what I could have spent. I might have $680 in them.

See, the trick is to get a good deal on them from E-bay. I bought mine for about $300.00.

The article sounds legit to me. If you can get 400hp from a Comp XE268 you can surely get it from a "Hot Cam" since it is roller and it has more lift.

I put the "Hot Cam" into the desktop dyno and the horsepower is over 400 and torque is way up there also. I think that it is over 400 from 2000 RPM and up. This would be a 12 second motor for sure.