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[Superdave]

I'm right in the middle of a 3500 swap into a Jbody, mounting is the easy part...

you'll have to swap over to larger injectors (atleast #19, preferably #24) and use the old 3100 fuel rail. your old exhaust manifolds will bolt back on the 3500 heads just fine. The Cam sensor may have to be spliced into.. no biggie there. then there is the external CPS. Hopefully it clears the subframe (dosen't in Jbody). you'll need a 65mm TB and adapter from the store here and that should be about it.

it will run horribly lean on the 3100 code, tuning is a must. but youre looking at a jump from 175 Crank HP to over 200.. and more torque too.

If you want more power then you'll be looking at a bigger cam, port work, headers and upgrading a few other things.. I'm expecting over 300 HP @ the crank with mine.. of course it's a 5 speed and won't be very streetable due to the cam. but it's not a DD so it dosen't bother me.

[Tdunk]

I'm not looking at it any other way i was planning on upgrading the 3500 lol. I didnt expect it to produce that much stock. I was planning on buying one then getting a regrinded cam, then ported UIM,LIM, and 65mm tb. I'll install a CAI to the TB. Then i'll put on a CBE just to make sure air flow is nice. Perhaps a new set of heads all though that would be expensive. I just need to know if the 3500 will be the engine of choice over a 3400?

[gectek]

3500 FTW!!!

[El_Diablo]

I'm not looking at it any other way i was planning on upgrading the 3500 lol. I didnt expect it to produce that much stock. I was planning on buying one then getting a regrinded cam, then ported UIM,LIM, and 65mm tb. I'll install a CAI to the TB. Then i'll put on a CBE just to make sure air flow is nice. Perhaps a new set of heads all though that would be expensive. I just need to know if the 3500 will be the engine of choice over a 3400?

yes but to get to your goal you'll still want to get a nice set of heads... the heads have a huge effect on power production

[Tdunk]

yea i know but arent heads like twice the price i'm going to pay for the entire engine. Ive found a couple of nice 3500's here for 950. The 3400's for some weird reason are really expensive around here.

Also i guess what ive read is incorrect. Umm the main prob i see with the 3500 is getting it running with a 3100 code to get to get it in there to be tuned. What i thought the problem was is that the 3100 computer injected a certain fuel ratio into the 3100 FOR the 3100 thats already been calculated. Thus why those calculations are much smaller since the 3500 will require more fuel. So if this is incorrect please someone correct me because i'm getting ticked at someone telling me i dont know crap and i dont know where else to look for this stuff. Its not like the manual explains this.

[gectek]

the injectors dont work on a certain duty cycle and thats it, they work off pulse width modulation. they dont have a certain on off time and thats it. they supply fuel based on the computers demand for it, and the computer does that by sending a letter in to the US Govt and asking them if the CARB/EPA regulations say its ok to use x fuel with y air to keep the ozone from depleting over the LA area and some parts of Mexico City, itll expect a reply the day before the world comes to an end.

If you use the MAF it should clean most of the driveability up, but it wont be at peak performance probably and wont run magnificent

[Tdunk]

lol uh well i live in ohio which has no regulations so i dont need to worry about it haha. I do use a MAF, but i dont think the fuel injector on the bu will work correctly. Its probably to small and if i do get a tune for the normal fuel injector i'd probably wear it out pushing it to much if i can get it to work properly. So with a 3500 i would have to get an upgraded fuel injector.

[gectek]

someone else can tell u about the fuel inj rating for your 3100, but if you have smaller than the 3400, use those, they will more than likely be a stock replacement, or the 4.2L inline 6 from the trailblazer, they are 28lb injectors and will work for better tuning if the other injectors are not enough

[Tdunk]

I believe its the same size as the 3400's but i'm not sure. Right now to ensure dont run into problems i'm looking into another 3100 and i'll build that one up. Then i'll put together a turbo setup. Not sure of the turbo i'd use or weather i'd use a single or twin setup. Still not sure once someone else does a 3500 swap in an N-body i'll look into it.

[gectek]

if you already got the 3500, dont waffle now, get to it. youll have plenty of help off here, and you could be the first to do it, then you wouldnt have to worry about anything.

just read the other threads on the 3500 and ull get more than enough info

also on the turbo, use a single

[Tdunk]

Uh well i didnt get it yet but around here the 3500 is cheaper than the 3400 thats why i was going to use that as a base. Still i just don't know i just got the money for the rims and tires which should help. Itll take 20lbs off the wheels. With a turbo setup i was wondering if i should build a case and use twin one right after the exhaust to help with air flow restriction and another right before the intake. Then again if single will work better i'll go with that... although its gonna be a bitch figuring out how to mount one and get a fully working cooling system to it.

[gectek]

not that hard at all, u said u had a malibu right, just go to the malibu forums and see what they have for pics, get ideas, and yah a twin turbo wouldnt be any good, nice novelty, but not as good as a single well designed turbo, and the routing isnt a prob really, and the oil lines and piping isnt too bad either. i would use the 3500 cuz you really wont need a turbo to get your hp goal really, and it is better designed for a turbo n e way, also itll have better power for just everyday

IMO i wouldnt use another 3100 and soak more $ into it, and there is no need to get diff rims even yet, they really wont do n e thing, but thats just my opinion

[El_Diablo]

single is best and is all thats needed, its easier too because you can just use a crossover pipe as a turbo manifold.. oh and BTW, most turbos still only use oil and all you have to do for that is tap into a source and then tap a return into the oil pan at a downward angle above the oil level

as far as the twin setup your talking about... what the hell are you talking about? lol

[Tdunk]

Oh uh well i havent bought them yet i just figured that they would help hmm..... Oh diablo well for a twin turbo setup umm well i'll talk to you in chat later i put alot of thinking into it but still wasnt sure weather a single or twin design would be better. Plus well i get the rest of my money here soon and my gas mileage from my CAI went up about 13% so i'll have a little more money in my pocket. I'll continue to save for the 3500. Hey ben or anyone any idea's on the price of heads that are ready for about... say i think the 3100 can take a max of 8psi safely so head to take 12 by any chance?

[El_Diablo]

i'll let ben talk about his heads but the head gasket is the weakest assembly around the heads and honestly, a stock head gasket should take around 15psi if not more... rarely will you see a head crack due to boost