Ok, so they sell a reluctor wheel for the 3500 to run it as a 3100/3400, as far as I understand it is a, take out the old 31/3400 and drop in a 3500 with the new crank sensor set up and you are good to go, or atleast that is how they seam to be selling it. Well I was thinking that if it is truely that simple, and the 3500s and 3900s are so similar can you just go ahead and throw the reluctor wheel on the 3900, "lock" the cam in one position, and hook everything up and go with it?

I know the 3900 intake has the variable link thing, is there any chance the 3500 or 3400 intake can take it's place? I guess the ported 3500s flow pretty well.

Reason for asking, is I just bought a 3100 swapped car, and the engine has 150k+ miles on it, and is leaking water, would love to replace it with a lower mileage engine, and thought $150 for a crank sensor set up, maybe I can just jump up to a 3900 instead of a 3500, also this is being run with a 7727 with a bereatta 3100 5 speed chip, I want to get a custom one programmed anyway, but would the obd1 with the 7727 be able to run the 3900 with the harness I already have?

Thanks

quote Originally posted by eph_kay: Ok, so they sell a reluctor wheel for the 3500 to run it as a 3100/3400, as far as I understand it is a, take out the old 31/3400 and drop in a 3500 with the new crank sensor set up and you are good to go, or atleast that is how they seam to be selling it. Well I was thinking that if it is truely that simple, and the 3500s and 3900s are so similar can you just go ahead and throw the reluctor wheel on the 3900, "lock" the cam in one position, and hook everything up and go with it? I know the 3900 intake has the variable link thing, is there any chance the 3500 or 3400 intake can take it's place? I guess the ported 3500s flow pretty well. Reason for asking, is I just bought a 3100 swapped car, and the engine has 150k+ miles on it, and is leaking water, would love to replace it with a lower mileage engine, and thought $150 for a crank sensor set up, maybe I can just jump up to a 3900 instead of a 3500, also this is being run with a 7727 with a bereatta 3100 5 speed chip, I want to get a custom one programmed anyway, but would the obd1 with the 7727 be able to run the 3900 with the harness I already have? Thanks

Anything other than a 3100 in place of a 3100 will require tuning

The 3400 is the next in line for a direct swap as is.

The 3500 will require an adaptor plate for the throttlebody and the external crank trigger you referenced.

The 3900 is available without the variable intake, and will require a throttlebody adaptor plate for starters. The cam can be left as is for bottom end performance, locked at full retard for highe end performance, or the cam can be left alone altogether and the cam sprocket lined up with the crank sprocket in a retarded position to get as close as possible to the cam being installed straight-up, as long as you are careful never to activate the module in that configuration, which would almost certainly result in exhaust valve contact with the piston.

You can also have the journals resized on an earlier cam for a retrofit of the smaller journal 3x00 cam and timing chain set, or acquire the cam bearing sleeves about to be made available to accomodate the earlier cam as is. Due to a difference in the block mounting bosses on the 3900 and other possible issues, the external crank trigger offered for the 3500 will not bolt up properly and would have to be modified in some fashion.

I had custom 7x trigger rings made for internal use which is what is installed on my engine, unfortunately the company that made them for me is being very slow to respond to a request to have additional pieces made.

Your current computer will control any of those engines with proper tuning.

awesome, thanks for the fast reply, it was exactly what I want to hear.

So on the tuning side of it, because the 3500 is seaming to be the path I should take, 200 hp is enough when it will be the back up car, can I get somebody to get a good enough tune since the engine will be an obvious change, that I could buy a preburnt chip?

Also will all the sensors plug in to my harness or will I need to change stuff on the motor?

Chris

quote Originally posted by eph_kay: awesome, thanks for the fast reply, it was exactly what I want to hear. So on the tuning side of it, because the 3500 is seaming to be the path I should take, 200 hp is enough when it will be the back up car, can I get somebody to get a good enough tune since the engine will be an obvious change, that I could buy a preburnt chip? Also will all the sensors plug in to my harness or will I need to change stuff on the motor? Chris

Sensor adaptation is up to you where necessary, you will have to source someone for tuning if you don't have the equipment to do it yourself. It really shouldn't be to hard for some of the mail order tuners using the stock 3100 tune as a base and the cylinder head flow numbers and camshaft specs found on the 60 degree V6 forum. The head flow numbers are available for both engines I believe including the 3400.

Thank you again, now all I have to do is luck out and find a good deal on 3500 before I find one on a 3400, and hopefully I do one of those before the engine dies

Chris

good luck with the 3500 tuning. shouldnt be hard to get one for stock paremiters. mine is a bit off from stock, and tuning it right now is a PITA.

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