Will 3400 cam work in non VVT 3500 block.

[Younggun88]

Basically can you you all of the 3400 Valve train parts on a non-vvt 3500 engine and if not why.

[SappySE107]

You can use any 3400 parts you want.

[Superdave]

the 3500 LX9 cam is identical to the 3100/3400 cam. Lifters, lifter guides and pushrods are all the same, i forget what year but i'm thinking it's '03+ 3400 and 3500 use 8mm rocker studs instead of 10mm.

[Younggun88]

I heard that you can swap the VVT-3500 crank in for the non VVT Crank. Is this true and also what would the new compression be. I am looking for a nice 8.0 to 8.5 for a turbo setup. If not is there any way of destroking the 3500 or lowering compression.

[Superdave]

I heard that you can swap the VVT-3500 crank in for the non VVT Crank. Is this true and also what would the new compression be. I am looking for a nice 8.0 to 8.5 for a turbo setup. If not is there any way of destroking the 3500 or lowering compression.

you could swap in a 2.8 MPFI crank and de-stroke it to around 3.1L.. custom pistons would be needed.


you don't need that low of a SCR to boost it, the stock 9.8:1 is fine. Lots of people are boosting 3400's with the stock 9.5:1.


IIRC the gen4 cranks have different size mains and won't fit the older blocks.

[Younggun88]

Well that sucks. I like the steel crank. guess custom pistons are the only choice. I know 9.8cr is ok but i am looking big boost. I have a 3800SC Fiero right now and with the 8.5cr you get a lot of safety. I am going OBD1 so my security is not as high. Do you think the engine with custom pistons can take 10lbs of boost while revving to 7,000rpms.

[Superdave]

i bet it could take 3x that with forged pistons... all depends on how good your tune is.

if you go with custom pistons, also look at upgrading the rods. the 3500 rods aren't the same forged pieces as the older '660 engines had.

[Younggun88]

Really 3x you say well i guess i know what my next swap is. Would 3.4 Camaro rods work because i know there is aftermarket there. also does the 3500 have return less fuel lines like the VVT has. Also would fiero headers work. BTW thanks for all the help.

[SappySE107]

If you grind the rod bearings down, yes. They are 2.25" vs the 2" of the older 60V6s. They are also 5.9" long vs 5.7". There is more custom work involved to make the 3500 engine forged rod and piston than a 3400 would be.

I think the 4.3 connecting rods modified are what were discussed last time, since they are 2.25" already.

Same returnless fuel rail as the VVT engines. I don't think headers for an iron head will fit aluminum head.

[Younggun88]

So now i have custom heads and rods. Can i use the 3400 fuel rail instead of the returnless. What are the largest injectors that would work. Can L67 injectors be used. That would be nice being that i have some already.

[bszopi]

Yes, you can use the 3400 fuel rail. As far as injectors, it all depends if you have the ability to tune the ECM or not. I'm hoping so, since you are talking about boosting the engine in the future. Any time you bump up the injector size, the tuning much change to account for the size change. If not, you will either end up dumping too much fuel at idle, resulting in a rich condition, or not dumping enough fuel at higher RPMs, resulting in a lean condition.

With tuning, you can adjust the fuel injector constant, and then adjust the fueling tables to work with the larger injectors.

[Younggun88]

Yes i can tune. I tune my Supercharged L67 right now. I would never do any engine swap without the ability to tune it in.

[ForcedFirebird]

If you grind the rod bearings down, yes. They are 2.25" vs the 2" of the older 60V6s. They are also 5.9" long vs 5.7". There is more custom work involved to make the 3500 engine forged rod and piston than a 3400 would be.

I think the 4.3 connecting rods modified are what were discussed last time, since they are 2.25" already.

Same returnless fuel rail as the VVT engines. I don't think headers for an iron head will fit aluminum head.

There was a thread at the 60* website that stated the possible use of LG9 4300 conrods with the 3500 crank. I went ahead and researched and found that the 4.3l chevy v6 con-rod have closely sized rod bores.

(2005 3.5 lx9 connecting rod rod main bore 60.322-60.338mm)
(2000 4.3 LG9 connecting rod main bore ....57.116-57.148mm)

I research and also found that the LB9 "305 cid" chevy v8 and 3500 v6 have a similar main bore

(2005 3.5 LX9 cyl bore ............................94mm)
(1990 5.0L LB9 (305 ci.V ......94.869-94.958mm)

It would be possible to buy aftermarket 4.3l rods and 305 forged pistons ,with aslight overbore for use in the 3500 motor. It may even be possible to modify a 3.4l block to accept the 3.5l crank and use 4300 rods.

3500+forged 4.3l rods+305 pistons equal bullit-proof 60*.

Driver just brought this up.

.........

[ForcedFirebird]

I heard that you can swap the VVT-3500 crank in for the non VVT Crank. Is this true and also what would the new compression be. I am looking for a nice 8.0 to 8.5 for a turbo setup. If not is there any way of destroking the 3500 or lowering compression.

9.6:1 with boost has been proven.



Does the VVT crank have the same bore spacing? I thought the 3500 VVT was a destroked 3900?

[Younggun88]

So if you overbore the block it can accept the 305 pistons? just making sure i understand correctly