I have been very interested in the 4200 vortec motor that's in the Trailblazer. I like the fact that it makes a decent power right out of the box, that it's a 6 in-a-row, it's proven itself to be reliable, and it has potential for either big power, or decent MPG. Now for me, the reliability, and MPG would be the goal. I've tried googling other people's swaps to get a feel for whats involved, but it seems like this just isn't done very often, and when it is, it's for high hp, or wheeling. EFI DIY seems to be the pioneer of the swap, and the truck makes me jealous! I would like to install this in an AD truck that I have on an S-10 frame, use a colorado 5 speed, and run it with megasquirt. problems I already see are DBW, oil pan, VVT, megasquirt selection/setup and possibly the transmission. Anyone doing this right now? Or does anyone know of any good links to people that are? Any help would be great, Thanks!

To my knowledge, Efi is the only one using megasquirt. There are a few swaps using stock engine management and a handful of carbed setups.
I highly recommend using the stock control system if you are not going for big power.

See my thread for a complete step-by-step:
http://forums.trailvoy.com/showthread.php?t=51636

I also put together a wiring how-to that's floating around here somewhere.

Good luck.

ECM usage will depend on:

a)If the engine is going to remain stock then the GM electronics if you can tolerate DBW is less painful.

b) how good you are with wires and computers.

If building a harness and tuning is not a problem for you then MS can work. It does take time and reading to be successful.

I am in the process of getting the sequential megasquirt (MS3) with VVT working - this is a work in process and I do not know yet what the final result will be.

Oil pan - I have a solution.

Well I'm not even going to pretend I'm good with tuning, but I've had an interest in megasquirt for a long time, but for other projects. This is something I would like to learn on and I don't expect it to be done overnight.

When it comes to using the stock PCM, what are options as far as tuning go? Cost? User Freindly?

The reason I thought megasquirt would be the best, was the fact that it's so versatile. I could change manifolds, delete emissions, port, or whatever and still tune it to stoic, or a little leaner (looking for MPG). And the initial cost of megasquirt seems fairly reasonable. I think I would be able to handle the wiring, and just take it one connection at a time, asking questions as I go.

For tuning the stock ECU you can use HPTuners or EFILive. A copy will run you $500-$800. Either will be able to handle what you're looking for and are very user friendly. You can download a demo copy of EFILive for free. HPTuners is similar.

Look at MS if you want: a cabled throttle, boost, custom VVT timing, etc.

I think efi might have some comments on mileage versus a 292 if you ask nicely

If you decide to go with MS2 (at least to start - easier to implement) I have a reasonable base tune which will get you started. Would need to know the engine year.. ( you are getting an 06 or later engine right... )

Limequat does HP or EFIlive let you mess with the VVT tuning?

I would like to get the newer model '06 and up motor. It seems counter productive to start with the earlier model.

The HPtuners and EFIlive sound pretty good as far as being user freindly, and it would be the easiest route to have the VVT working. Is this similar to megasquirt as far as tuneability? What would be the downside to this route (if there is one)?

EFI, you say that the Megasquirt 2 would be the one to start with. Would I be able to control VVT? You deleted the VVT on your engine correct? Did this hurt MPG or power? Like Limequat said... How does the mileage compare between a 292 and a 4200? And the ultimate question... If you did it over again, would you still go with Megasquirt? I appreciate all the good feedback!

This is awesome stuff.... not to hijack the thread, but I see a lot of damage being done to moderate mileage newer engines from lean fuel (exhaust valve damage and cracked combustion chambers in newer vortecs, hemi's and LS style) and low octane fuel. It goes without saying that hardened seats are a must in older engines, and now that zinc is not widely available in motor oil (Brad Penn still does.... at almost 7 bucks a quart) is it wise to intentionally run an engine lean? The last 235 head (second gen) I had in the shop looked like it had been pounded to death. I asked the guy about his fuel purchasing habits and he said he bought whatever was cheapest. AUUUGGHHH!!! If it wasn't bad for business I ask them if they want to pay a little more at the pump or pay me a bunch of money later for valve jobs or buy new heads. Believe it or not the rotating assmblies are lasting easily 200k without a problem. Lean engines and low octane will kill your valve train. JMHO

EFI, you say that the Megasquirt 2 would be the one to start with.

Depending on your time frame to get this running - MS2 has many installs and the s/w is stable. It does not run VVT. MS3 with VVT operation is under development now. I never had VVT in operation so its hard for me to comment now.... ask in 8 weeks.

My 292 got 14 MPG highway. The stock 4200 got 25-27 MPG highway. My built motor gets 16-18 MPG but its also making 300HP at part throttle.

I was already using MS on another vehicle so it was a natural.

Starting from scratch.. don't know - I'd have to see and use HP tuners / EFI live before making a choice. There is something to be said for OEM electronics if the engine is staying near stock.
On the other hand folks on trailvoy are starting to run into limits on the stock tune.

Depends on the year.
02-05 there is a base cam angle versus fuel trim cell.
06-07 you cannot adjust the commanded angle
08-09 hardcore 3d maps

They say hindsight is 20/20 ... my rearview is foggy.

Getting the engine running was so easy using the stock controls. Just wired, add fuel and go.

However, I come from hacking late 80s to early 90s GM injection where we could do whatever the hardware would support (I have a mazda running a chevy v6 on a sunbird ECM with corvette software). I remember manually coding s/w patches directly in hex. That's flexibility.

The commercial s/w packages don't have that flexibility and it's really tough to be at the mercy of a third party hacker. You're best bet is to know what you want to change in advance and see if the commercial packages can do it. Looks like this is already done.

If I had to start over...I probably would skip the VGT turbo! And I would have definitely have bought Efi's pan (if only it were done when I needed it).

I'm rambling. The point of this post is to say that even though I'm pretty happy with the stock controls, I'm going to be running both! Stock efi for the injectors, coils, and VVT. MS for my bizarre turbo. Best laid plans and all that jazz.

Any chance you have the stock 08-09 VVT maps ? Would be a good starting point.

This is for medium baro pressure. Surprisingly, they actually pull a lot of caming timing for low baro.

Let move this to its own thread - kind of did a hijack.

So, with your guys' input, I think the best route for me would be to run with the stock electronics at first. I will be able to get this with the engine, and if it seems limited for me, I can always try something else.

Where would be a good place to find an engine? Again, I would like to find the '06+ model, and I want something with the electronics, and I won't need the 4L60E. I glanced at ebay and didn't see anything in the Portland area, and I tried craigslist...

To use the colorado 5 spd, can I just use the I5 flyweel, clutch, pressure plate, bellhousing and transmission? Do you think the shifter would interfere with a bench seat in an AD truck? Would there be a problem with using the trailblazer computer, and a colorado trans?

EFI, will that oil pan you offer be a bolt-on deal? Or does it require any additional work? Price? Ordering info?

Look on http://www.car-part.com for an engine. Good deals come up on eBay too if you're patient. For the manual, all colorado stuff will work except the flywheel. You need a custom piece from Jerry Weigt.
I can help you with the calibration to make the manual work in the PCM.
Can't help you on fitment, I drive a Supra.

You need to modify a colorado pickup and drill the oil dip stick hole to suit your exhaust.

details are on http://www.emtechmotorsports.com email from there and I'll help.

Any idea on gear ratios in the Colorado 5 speed? OR, can the supra trans be used in this (55-57 chevy passenger car)?

Subscribed. I've got a 56 with a 235 and a glide and eventually I want a Vortec 4200 and a manual trans.

Colorado Ratios:
3.75
2.26
1.37
1.00
0.73
3.67 (reverse)

The Supra trans will also bolt to the colorado bellhousing. The ratios are better, but you give up the triple cone synchros.
Supra ratios:
First Gear: 3.250:1
Second Gear: 1.955:1
Third Gear: 1.310:1
Fourth Gear: 1.00:1
Fifth Gear: 0.753:1