some new 3500 specs...

[v6h.o.]

i think we all know these first few specs, im just going to post them anyways, but there have been changes internally to crank/ conrod, and piston pin specs. here's what i found checking out our online service manuals:
Displacement
3.5L
214 cu in

RPO
LX9
VIN
8

Bore
94 mm
3.70 in

Stroke
84 mm
3.31 in

Compression Ratio
9.8:1

cams are the same lift:
Camshaft Lobe Lift - Exhaust
0.2727 in
Camshaft Lobe Lift - Intake
0.2727 in

Connecting Rod Bore Diameter
60.322-60.338 mm
2.375-2.376 in ( up from 53.962-53.978 mm /2.124-2.125 old spec)

Connecting Rod Length - Center to Center
150 mm
5.9 in (old spec 5.7inch)

5.9 INCH RODS! thats a 1.78 ROD STROKE Ratio!
up from the 5.7inch 1.72 rod/stroke ratio. not much of change but still better ratio than before.


Piston Pin Bore Diameter
24.008-24.013 mm 0.9452-0.9454 in
(old spec 23.005-23.010 mm / 0.9057-0.9059 in)

Piston Pin Diameter
23.997-24.000 mm 0.9447-0.9448 in (same pin diameter as the New LS_ GENIII small block engines)
(old spec 22.994-22.997 mm / 0.9053-0.9054 in)

just thought i'd post this for those inquiring minds. as i know a few of us are watching this engine with feavered antisipation to get our hands on one for a base to start an all out high performance build from. (i know i am)

[robby1870]

huh, longer rods. Thats good, brings that rod/stroke ratio up, closer to 1.8 (I think 1.8 is ideal, right?) That ratio has something to do with some term, dwell, I think, hell I cant remember. Wonder why the made the lifts on intake/exhaust the same?

[bszopi]

The cam profile has been the same since the 3100 debuted in 1994...

[robby1870]

The cam profile has been the same since the 3100 debuted in 1994...

Yeah, sorry, I was thinking about my 3.1L.

[Sorin]

Hmmm. That compression ratio just keep getting higher and higher. Wonder if we are going to see LS1-like compression (10.1:1) in the next displacement or generation

[Guest]

Cool, I want to see the insides of one of these, to just how "impossible" it is to use that rotating assembly in an older block.

[Blackrider]

I'm really looking into The problems that would come with swaping the 3500 into my 2001 Grand Am GT.


First off, some different sensors IE Cam sensor witch was changed on the 3400 in 03.

Second, Power steering... Might be able to just swap over the 3400 Pully system.

Therd Trottle Linkage... Does anyone know if the 3400 upper/lower intakes are simmaler to he 3500?

Forth Fuel rails... once again does anyone know if the 3500 and 3400 share simmaler upper and lower intakes?

Does anyone know the Diff in the heads?

If the exhaust side of the head is the same I could just slap on my current S&S headers.

Keeping in mind i have no problems cannibaliseing my 3400 I'm going to still be using the stock PCM, There might be some diff in fuel tables but the computer will be reprogramed nextyear anyways.

Anyone have any imput solutions more possible problems?

[v6h.o.]

First off, some different sensors IE Cam sensor witch was changed on the 3400 in 03.

swapping out your cam to use in the new block is easy enough.

Second, Power steering... Might be able to just swap over the 3400 Pully system.

the P/S pump simply bolts onto the 3500. its just the malibu is now using a non hydraulic steering assist system. the flange still has the 3 p/s bolt holes for the p/s pump, its just not used.

Therd Trottle Linkage... Does anyone know if the 3400 upper/lower intakes are simmaler to he 3500?

the lower intake manifold looks right now like its identical to the regular 3100/3400 intakes. the upper is different in a way. the pysical dimensions are different but if its to bolt to the old style lower it seems like its the same port size and configuration.
i'll have to look again and see but i think the 3400 throttle body should bolt up to the plenum. but then i dont think it has provisions for the throttle cable bracktry.
if the lowers are the same however you could simply use the 3400 plenum on it. which would be nice and steathy... 3400 badging,.. larger displacement. no-one needs to know.

Forth Fuel rails... once again does anyone know if the 3500 and 3400 share simmaler upper and lower intakes?

the fuel rails are different due to the new upper plenum. again if you went with using the old 3400 plenum, you could use the old 3400 fuel rail. but again this is not 100% known, im wanting to tear into a 3500 sometime soon, at work to find all these questions out.

Does anyone know the Diff in the heads?

looks like so far the addition of the coolant sensor threaded holes in the sides of the heads is the only exterior physical addition, interior changes, not sure yet.

If the exhaust side of the head is the same I could just slap on my current S&S headers.

yes. they should be identical, i cant see GM changing the exhaust port. the S&S headers are really large on the exh flange opening as you wont have any worries as per if the port is slightly bigger.

[Blackrider]

Well Colin When i get you all payed off Would you like to asist me in a 3500 swap next year if i can find one, i might have to fight you for the engine though