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Posted

This is the block/transmission for the AWB Chevy II Nova Streetfreaks kit. I've got it aligned as best I can, but , one side (right side in photo) is further forward than the other, which means the heads will be the same, which means the headers will be the same. How do I correct this, or , can I? Is this the way AMT expects you to build the engine? Thanks, any input is welcome.

IMG_0986_zpsaogzqlrt.jpg

Posted

there are a lot of V-type (V12, V10, V8,etc) engines that have the heads offset...I'd guess by the width of a piston connecting rod.

I suggest aligning the engine halves so that the ridges of the bell housing line up then make any corrections to the other parts of the block that don't appear correct.

Posted

there are a lot of V-type (V12, V10, V8,etc) engines that have the heads offset...I'd guess by the width of a piston connecting rod.

I suggest aligning the engine halves so that the ridges of the bell housing line up then make any corrections to the other parts of the block that don't appear correct.

About the only Vee engines that didn't have their cylinders and heads staggered at least a little bit were those very early V8's which used a rather strange "fork and blade" connecting rod setup. With that style of connecting rod, the rod on one side of each crank throw journal was shaped very much like a right-angled "fork" with bearings in each leg of that fork. The opposite rod big end looked very much like any modern V8 connecting rod, it's big end going in between the two legs of the forked rod. That worked for those relatively low-hp per cubic inch engines of 90-100 yrs ago, but was replaced pretty much by at least 1930 by the more modern (and better) side-by-side placement of connecting rods two to the crank throw, just like is seen today.

Art

Posted

Okay, thanks you guys. So, then the headers (because the heads will be offset) are going to compensate for this and be of equal length on each side, or , they too will be staggered slightly?

Posted (edited)

we

Okay, thanks you guys. So, then the headers (because the heads will be offset) are going to compensate for this and be of equal length on each side, or , they too will be staggered slightly?

well, that's a little hard to answer but in an exhaust system designed to have the same amount of exhaust scavenging for each cylinder, the headers would be staggered also.

to have them end at the same point (mirrored) would change performance seen from each head/cylinder.

there's a whole lot of science behind engine performance and how an engine "breathes"... what comes in must get out but there are many factors to consider to get the performance out of an engine for the purpose intended.

Edited by blunc
Posted (edited)

I always cut the locating pins off the engine halves. I then sand each half flat on a piece of fine sand paper. Lay the sand paper on something flat and slide the engine half across it. I have a piece of 3/8" glass on top of my work bench that works great. I then wet the edge of each half with liquid cement (I like Testors) and line up the halves up as best I can. With no locating pins I can shift the halves in any direction to get a better alignment. After the glue sets up I cleanup all the edges and offsets.

Edited by afx
Posted

I always cut the locating pins off the engine halves. I then sand each half flat on a piece of fine sand paper. Lay the sand paper on something flat and slide the engine half across it. I have a piece of 3/8" glass on top of my work bench that works great. I then wet the edge of each half with liquid cement (I like Testors) and line up the halves up as best I can. With no locating pins I can shift the halves in any direction to get a better alignment. After the glue sets up I cleanup all the edges and offsets.

That's almost exactly what I do, too. Only minor difference is that instead of wetting each half with the liquid cement, I hold the halves together and then touch the brush to the joint. Capillary action sucks the cement into the crack instantly. I usually have to do this in three places for full coverage but the whole process takes less than a minute.

Posted (edited)

This is the block/transmission for the AWB Chevy II Nova Streetfreaks kit. I've got it aligned as best I can, but , one side (right side in photo) is further forward than the other, which means the heads will be the same, which means the headers will be the same.

It looks like everything else but the very end is out of alignment... when this happens to me, I treat the small extension as a piece of flash and sand it even with the other side. Haven't noticed any other problems related to it, but then again, I haven't really been looking for them... ;)

Edited by fseva
Posted

Mike, thanks for the info, It will be interesting to see how the headers line up lengthwise when I put them on. I'm learning a lot about engine because I'm a modeler!

JC, and Richard, I've done the flat sanding thing before, not sure why I didn't on this block, maybe I'll make it a regular practice.

Frank, I used other facets of the engine to line things up (well I tried, lol), sometimes the tranny ends are uneven, I fixed that.

Thanks you guys, I appreciate all the great info, and , help. Sometimes I feel like I'm on my first build. :P My next goal is to not have the seams show, which is always a challenge for me on engine blocks.

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