3100/3400 top swap

[ShaneLT(ShaneZ26)]

Just wondering would I have to remove my 3100 to do a 3400 top swap on it? Or can leave the engine in? What is all in involved in this swap? Any write up on it?

[Barry]

No, you can ea silly do it in the car. I just support the engine with a peice of wood and a floor jack, remove upper motor mount, P/S pump, maybe alternator, then start pulling everything off. Start with coilpack bracket then valve covers then UIM then fuel rail(just pop injectors out of LIM, no need to disconnect lines), then pull the upper rad hose and the LIM.

Are you doing heads too? If so, start soaking exhaust bolts with wd40/pb blaster.

[ShaneLT(ShaneZ26)]

Yea I'm thinking bout it.

[Chad91GTZ]

Seafoam Deep Creep has WD-40 and PB Blaster beat all to hell.

[ShaneLT(ShaneZ26)]

Would I benefit from it? What would my HP/torque gain be?

[Barry]

You will probably be able to feel it I suppose. I did the swap a few years back. That same car ran a best of 17.0x at beaver springs dragway haha. But its getting tired now I suppose.

[Chad91GTZ]

Its going to breathe better for sure If you use the right parts.

[ShaneLT(ShaneZ26)]

What do you mean by right parts? And don't I need the 2000+ egr adapter? Also could I use an AC compressor from a 3400 on my 3100?

[Money pit Beretta]

Yes you need the adapter from WOT-Tech. That way you don't have to try and swap the tube that goes from the manifold to the EGR(when using a newer EGR). By the way watch out for the fresh air PCV tube. It will sit on one of the bolts for the EGR and melt. Ask me how I know(lol). Last I remembered you can use a 3500 PCV tube to counter act this. I had to use a zip tie because I couldn't find one.

[Money pit Beretta]

Oh and it's a 10hp gain, 20hp with a tune that you can't do with the stock computer. Pulls a hell of alot better I can tell you that for sure even without the tune. If you have the money 99 Venture van injectors will work with you computer. In other words you will be far from maxing the injectors out and they are better injectors.
I think the chambers are better for the newer heads. I know that the port size is the same as your stock ones though. It's just the upper part of the lower that's bigger, not at the head. I'm still running my stock 95 3100 heads and 3400 uppers.

[ShaneLT(ShaneZ26)]

Well would 02 venture injectors work? I have the whole van. I plan on taking the comp from it. The only reason I'm gonna do top end only Cuz I'm gonna do a 3500 swap eventually. What else should I grab from it? Harness? I dunno like I said I have a complete 02 venture. I'm gonna sell whatever I don't want the sell the body and whatever else don't sell to the jy.

[Money pit Beretta]

I'm out on that. You will have to wait for 3X00 to reply. My 99 Venture info was from him. Not to say that he is the only one that knows about this, just that he is where I got my info.
Not sure if the Venture is supported by HPT. I don't think it is. The computer would be worthless if it's not.

[beretta]

quick question... will a 3400 lower and upper bolt onto a 3.1 not 3100 ? i have both pieces of the intake and was going to put it on the 96 but doing a full 3400 swap now, i still have the 88 3.1 to play with

[3X00-Modified]

You need all 3400 parts from the block up on a 3.1 L including custom length pushrods. The head design is totally different but it can be hybridized.

Shane, you need
-Heads (if you want them)
-Lower Intake (03+ Best but others ok)
-Upper Intake (2000+ best)
-EGR adapter
-3400 TB (swap over your linkage rod from 3100 one)
-96-02 roller rockers for clearance, You can only use those on the new 3400 head, or if your current ones have notches where the rockers mount, you would remove the stud for the ball pivot rockers that are currently there as well as the pushrod guides. If you don't use the 3400 heads with rockers or if they wont fit on your 3100 heads then you need to clearance the corner of the rocker and the lower intake, the stamped steel ones will rub the larger ports on the 3400 intake.

No harness is needed, but you will have to re-wire your coolant temp sensor. You have two choices IF you swap out heads... Put a 2 pin sensor where your current one is and the sensor thats in the back head you can install in the rear block drain port, or you can re-route that wire and make the 2 pin sensor a 3 pin one like on a 96+ beretta.

Stock injectors on a 95 will run fine. I used the 99 3400 Venture injectors when I did mine since 3100 ones are 17lb and the 3400 ones pre 00 are 19lb Slight safety net since I was spraying.

97 Venture is NOT supported by HPT. You would need to use a 97 Monte Carlo ECM... Granted the are both the same ECM but HPT will not let you fully overwrite an OSID to my knowledge so you need to start with the right platform. I can take any one and flash it to the DHP supported venture file I'm using since I can do a full write. But the HPT needs to be linked to a vin or specific ECM IIRC. Cliff can verify that more.

You cant use larger injectors as your planning due to not being able to tune... the 19lb ones the ECM can compensate, and larger and the computer will over fuel the engine and not be able to adjust for it. 02 venture is 22lb injectors.

If you want to do any harness swap to gain tuning support, your best bet is still to find a 96 beretta or corsica and do that engine bay harness and follow my OBDII upgrade thread. Any other harness and your just asking for re-wiring nightmares.

[ShaneLT(ShaneZ26)]

OK so where do I get custom pushrods or roller rockers? And on here
http://www.hptuners.com/forum/showthread.php?t=32677
it says they support 02 venture. So I would just need a 96 Beretta harness for the obd II swap?
And how do I re-wire the sensors. Like I'm not gonna do the comp swap till later when I do the full 3500 swap. So will my ecm work OK with a 3400 top end swap?