426-Cube 318 Poly Can Outgun Hemis
- Thread starter Sedanman
- Start date
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That's badass. But no surprise.
X2 Polys aren't a bad design.
harrisonm
Well-Known Member
I'm not surprised either. I remember an article in Car Craft about 20 years ago that set a budget of (if I remember right) $2500 for a build of a 350 Chevy, 302 Ford and a LA 318. Guess which one made the most power.
diymirage
HP@idle > hondaHP@redline
impressive...but not a poly
not to be a jerk about it, and definitely not knocking their build, but thats a LA engine, with poly heads and a chevy intake, but still a LA engine
on the plus side, i like the adaption of the ford headers, that may be useful to someone building a poly engine
not to be a jerk about it, and definitely not knocking their build, but thats a LA engine, with poly heads and a chevy intake, but still a LA engine
on the plus side, i like the adaption of the ford headers, that may be useful to someone building a poly engine
Your splitting hairs on stupid things.
Poly heads on a LA block is demoting the build to a non poly?
Have you ever had the 2 blocks side by side?!?!?!
On a personal note on the build, I'm not exactly amused by it because it isn't something the average guy would do.
I can see it took some thinking and making one off parts and reworking other brand parts to fit and function which is a lot of work. Highly commendable but it doesn't give me warm fuzzy feeling of ever really seeing such a build or similar power build running the streets.
Bottom line, I'm not impressed with the impressive work.
Lustle
Well-Known Member
551 Hp and 563 TQ?
Yeah that's cool.
Yeah that's cool.
diymirage
HP@idle > hondaHP@redline
nope, i have never seen the two side by side
but what makes it an LA or a magnum or a poly or a B or RB ?
its not the heads, though each head is designed for each block, it is the block
if i were to make hemi heads fit a magnum would i have a hemi or a magnum?
if i were to bolt 340 heads to a 318, what would i have?
that was the way i was looking at it
stroked340
Well-Known Member
I think I'd take a hemi over that..I'll bet they got as much in that as the cost of a hemi..
DyiM, As mentioned in the article, the 2 blocks, the A and the LA are nearly identical and you would be hard pressed to tell the difference.
The difference between the LA & Magnum and the "A" are one small change each.
Fitting HEMI heads into a Magnum? There is a fella that makes small block HEMI heads. But I think you mean a set of Gen 2 or 3. If such was possible, I would call it a HEMI headed Magnum. That's what it would be. Not solely one or the other.
340 heads on a teen? Ether a 340 headed teen or just siamply, a small block that displaces 318 cid's. Yep! I'd call it a 318 due to its cubes. If asked, yep! I'd fess up to 340 heads.
The difference between the LA & Magnum and the "A" are one small change each.
Fitting HEMI heads into a Magnum? There is a fella that makes small block HEMI heads. But I think you mean a set of Gen 2 or 3. If such was possible, I would call it a HEMI headed Magnum. That's what it would be. Not solely one or the other.
340 heads on a teen? Ether a 340 headed teen or just siamply, a small block that displaces 318 cid's. Yep! I'd call it a 318 due to its cubes. If asked, yep! I'd fess up to 340 heads.
On that mention, I don't "Think" but I "Know" I'd take the HEMI.
And while I'm at it, I'll make mine a 528 or greater.
The "poly block", was not, it was the "A" block with polyspherical heads. The very term "poly" that defines the whole eng. in reference, is the design of the cylinder head.
W/o those heads, the block is just an "A" series block, and is simply the 1st step that led to the "LA" block(Lightened A series). If You've learned nothing being a member
by now,You should know that the performance potential and efficiency of an engine is completely dependent on the cylinder heads, and the appropriate choice of comp-
lementary components. Any engine with poly heads is a poly engine, the block below is just 8 holes in a "V", and can only offer reliability to handle whatever is on top can
dish out.
needsaresto
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An Edelbrock Victor Jr. manifold from a GM LS1 application happened to have ideal port spacing and provided the raw material. The injector bung bosses were machined from the mounting flanges, then the work of mating it to the W2-style intake ports began.
Interesting. Did Chevy rob the poly design for thier LS series?
Interesting. Did Chevy rob the poly design for thier LS series?
Looks like a couple of knowledgeable GM guys that made it happen.
My opinion probably ain't worth squat, but to be a poly to me, it should be a full poly.
Block and heads.
Jeff
Block and heads.
Jeff
stroked340
Well-Known Member
Hmm..same can be said for guys running 318's with 340/360 heads on them and claiming they're a 318..
Or strokers...???
Jeff
Heck, it has Honda bearings. Lol
It's a 318. If they claim 340/360 due to the head alone, a shrink is needed.
xLURKxDOGx
"An angel fat, at satan's feast"
The biggest plus to that "A" block is that it's about 30 pounds lighter, and will actually fit in an A-body. It would be nice to see some footage of it on the dyno.
Jake
Jake
I disagree, Heads are what makes an engine.
Especially the first 3 you quoted
The main difference between poly, LA and magnum are the heads that's what makes them block wise there very similar.
Even the new hemi is basically hemi heads on a very modified LA short block even though nothing is interchangeable it still has the basic dimensions of the LA's rotating ensemblely.
Of course R and RB engines are different cause it's a completely different engine but the main difference between 426 hemis and the later again is just the heads.
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