Difference in 3400 and 3500 Camshaft Housing Bore?

[sprucegagt]

I've been checking out Dura-bond's new 2010 catalog and noticed what may be a problem. I was under the impression that 3400 and 3500 cam bearings were the same diameter. But appearently they're not.

3400 Camshaft Housing Bore
Position 1: 2.0100"
Positions 2 & 3: 1.9995"
Position 4: 2.0095"

3500 Camshaft Housing Bore
Position 1: 2.1766"
Position 2 & 3: 2.1565"
Position 4: 2.1766"

Now where this may be a problem is if you wanted to use SBC cam bearings in your 3500.

5.7L/350 Chevy Small Block Gen I
Camshaft Housing Bore
Position 1: 2.0200"
Position 2 & 5: 2.0100"
Position 3 & 4: 2.0000"

As you can see SBC bearings are ~0.14" undersized for the bore, thus they won't fit properly.

[Weatheralls Auto]

I have not checked myself, but are you sure you were looking at a Non VVT 3500?

Just curious.

[sprucegagt]

Yes, verified against this site by VIN code. Dura-Bond doesn't go by RPO code.

I also should note that the #1 position cam bearing is wider for 3500 than 3400.

3400 Position 1 Cam Bearing Width: 0.625"

3500 Position 1 Cam Bearing Width: 0.905"

All other positions had the same width between 3400 and 3500.

[SappySE107]

sounds like a VVT 3500 to me.

[Superdave]

3400
Camshaft Bearing Bore Diameter-Front and Rear 2.009-2.011 in
Camshaft Bearing Bore Diameter-Middle #2 and #3 1.999-2.001 in


3500 LX9
Camshaft Bearing Bore Diameter - Front and Rear 2.009-2.011 in
Camshaft Bearing Bore Diameter - Middle #2, #3 1.999-2.001 in


3900
Camshaft Bearing Bore Diameter - Front and Rear 2.175-2.177 in
Camshaft Bearing Bore Diameter - Middle #2, #3 2.155-2.157 in



that's the info that's on this site... i can check my 3500 block tomorrow though.

[sprucegagt]

What's the VIN for a VVT 3500?

[Weatheralls Auto]

I beleive in 07 it would be a Vin 1 LZ4 or LZE

[bszopi]

I guess I could go measure mine... Will do after dinner.

[bszopi]

I just measured 2.010" on the the first hole.

[Superdave]

that must have been a quick dinner...

[sprucegagt]

I just measured 2.010" on the the first hole.

<- Brad's dinner

I guess their catalog is wrong. But they do call out a 3.5 L VIN 8 with those characteristics. Oh well.

[bszopi]

I squeezed it in before dinner. I did knock over my 3500 crank trying to pull the engine out as well...

[3400-95-Modified]

I sold a 3500 cam to someone to put in a 3400... never heard about any issues with it so I would assume this is wrong.

[sprucegagt]

The cam isn't the issue, just cam bearings, or well they were.

[3400-95-Modified]

Ok, wasn't sure if you were trying to say that the .14 difference also carried over to the cam or not.