The 4200 enigne has a lot of potential for engine swaps and some folks like myself are starting to do them.
Well I don't have a trailblazer but I do have a 4200 in a '51 GMC running NO GM electronics ( megasquirt and FORD EDIS wasted spark). This winter its getting a GT42 turbo along with a stout bottom end (pistons, rods, darton sleves) and custom cam shafts. <<< doing the design for the CNC cam blanks this weekend.
Once we have the cam blanks ($500) then we'll send them to a cam grinder to get them ground into cams (another $700). The prototype turbo manifold is getting done at www.steedspeed.com. The CNC intake flange is enroute to start the build.
Im interested in this, before i even bought the TB i was thinking of boosting it, mainly a SC. But the more i look at it a turbo might be pretty good. Looking good so far :thumbsup:
Ive been looking for an engine for my s-10 blazer and this will put out pretty close to a carb SBC. Not the mention the 4200 is lighter than a 350, and it would mate to my 700r4 with no problems. I want to see some more info on your fuel and ignition setup as i dont want to run the electronics.n
Well the 4200 does not have a dist. so you will need to run electronics for spark control. You could build a custom intake and run carbs - but why? It a lot less work to hookup a megasquirt than fabricate an intake. But thats just my take on things. If you do decide to go with a megasquirt I can send you the calibration file so the tuning will be real close.
Well the cam cores are designed and ready to goto the machine shop. We're getting them cut from 8620 round bar. GM does not sell cam cores for this engine and the aftermarket doesn't have them either - so the only way to get non-stock cams for this engine is to design and machine cam cores then send them to a cam grinder.
Well the cam cores are designed and ready to goto the machine shop. We're getting them cut from 8620 round bar. GM does not sell cam cores for this engine and the aftermarket doesn't have them either - so the only way to get non-stock cams for this engine is to design and machine cam cores then send them to a cam grinder.
MEGASQUIRT huh?? Buddy of mine has been running that in his VW Scirocco and Rabbit for a year or so now. Swears by it, and hes NA.
Glad to see someone who uses this engine in a hot rod is actually posting up here for us! Good luck with the build, and if you have questions about the engine feel free to ask anyone (or me)!
What have you done with the exhaust cam VVT, nothing or have you swapped the cam already?
Turbo manifold design is 99% complete - just waiting for the wastegate to show up.
This manifold design has a dual outlet top and bottom - when installed in my 51 GMC the turbo will sit on top of the manifold with the wastegate underneath. For a trailblazer application it would be REAL easy to reduce the top outlet height to mount the wastegate and then mount a turbo on the bottom outlet.
Great work!!! Love the wooden oil pan. Is that the stock TB header in pic #24? Looks like you can fab almost anything. Can you do a rear spoiler like what was on the concept TBSS?
First of all I love these engines and plan on picking one up very soon. Glad to see GM bringing back the inline engines.
If you could pick up an engine complete with harness and ECU could you just let the factory ecu control everything instead of doing it with megasquirt? I understand that you are wanting to go beyond the factory setup, but would a straight swap like I mentioned work?
I love the idea of putting these in older chevy trucks, because the inline 6 is what alot of them had originally. That's my plan - to swap one of these into a 67-72 chevy p/u.
I've also registered at inliners.org because I heard some guys there have information regarding these engines, but I haven't gotten a confirmation back from them yet. It's been a week. Are you involved at inliners.org?
BTW here's a picture of a twin turbo 4200 in a concept Trailblazer that I ran across.
what is the length of the block of this 4.2 I6? I am looking for a swap candidate besides an LS1,2,4,6 for my Porsche 944...Also what is the height from center crank to top of intake manifold....thanks in advance...BTW this 4.2l motor is definitely a cool motor...thanks
efi-diy, Im continually impressed by your work. Cant wait to see that final header, going to be a bunch of guys lining up for one once we figure out the GM electronics aspect for the regular GMT360s.:thumbsup:
I'd like to see if this manifold will "as is" in the trailblazer. Could you take some measurements please.
The manifold is 9 1/8" wide measured from the exhaust port surface on the far outside vertical surface of the turbo flange.
From the top of the exhaust flange to the top of the turbo flange its 2".
Add another 9" from the top of the turbo flange to the underside of the hood ( this is for a Garrett GT4088 turbo).
The wastegate flange is 8 below the top of the exhaust head flange ( easier to measure with the stock exhaust manifold installed.. ). The Tial wastegate is 5 3/4" tall and bolts directly to the wastegate flange. I suspect we'll get interference here and the lower flange will need to be tweaked with is not hard to do.
I'd like to see if this manifold will "as is" in the trailblazer. Could you take some measurements please.
The manifold is 9 1/8" wide measured from the exhaust port surface on the far outside vertical surface of the turbo flange.
From the top of the exhaust flange to the top of the turbo flange its 2".
Add another 9" from the top of the turbo flange to the underside of the hood ( this is for a Garrett GT4088 turbo).
The wastegate flange is 8 below the top of the exhaust head flange ( easier to measure with the stock exhaust manifold installed.. ). The Tial wastegate is 5 3/4" tall and bolts directly to the wastegate flange. I suspect we'll get interference here and the lower flange will need to be tweaked with is not hard to do.
On another note I'm working on a turbo intake manifold that will allow the stock fuel rail/injectors to be maintained and add 1 or 2 more injectors per runner with separate feeds for each injector. The ideal here is to be able to run either <100% methonal, or a mix of 100 octane unleaded and methonal or just 100 octane unleaded. I'll be set up for a LS1 cable type TB but with an adapter plate the stock 4.2 TB can be bolted on. If running 100 methonal under boost the turbo could blow directly into the intake as the methonal would cool the charge enough to keep detonation away. Might be an easier install rather than trying to find a home for an intercooler and plumbing...
This might be an alternative to trying to get the GM PCM to accept boost. If the GM electronics keeps the spark going and keeps the throttle open under boost conditions (maybe you know the answer).. Then a supplemental controller could take over the fueling under boost conditions e.g. start adding fuel @ 120 Kpa, then the GM pcm can shut its injectors off and the engine would keep going and not go into limp mode if the ignition is kept alive.
For my 4.2 build I also have spec out the custom Darton sleeves, Crower rods and J&E pistons. Also the block is getting main and head studs. The head is getting O ringed to prevent gasket issues.
On another note I'm working on a turbo intake manifold that will allow the stock fuel rail/injectors to be maintained and add 1 or 2 more injectors per runner with separate feeds for each injector. The ideal here is to be able to run either <100% methonal, or a mix of 100 octane unleaded and methonal or just 100 octane unleaded. I'll be set up for a LS1 cable type TB but with an adapter plate the stock 4.2 TB can be bolted on. If running 100 methonal under boost the turbo could blow directly into the intake as the methonal would cool the charge enough to keep detonation away. Might be an easier install rather than trying to find a home for an intercooler and plumbing...
:iagree:
I've heard lots of guys swear by this. It's the way I'm going when I build my turbo small block:thumbsup:
Keep us updated on this!!:yes: Very interesting!
Marc, Id love to run out and grab measurements for ya but my TB is 300mi away from me in Seattle at my parents house. Wont let me take it to college my frosh year, so its t-minus 20 days and counting till I get it back.
And right when I get home I fly to Denver, so I cant get you measurements for about a month. Someone else please step in here and grab them??:hail:
And you can trick the P10 PCM from 02-05 to not go into REP mode, just have to run a voltage clamp on the MAP sensor then run a standalone spark control module (plus whatever extra fueling stuff). My issue is I want a 100% factory setup, run a stock GM PCM and have it control everything. I could probably make it work a lot easier with standalone stuff, but I dont wanna. :laugh::dielaugh::bonk:
I like the meth idea, these engine bays are small enough already (look at the heatsoak issues the SS guys have stock, let along MagnaCharged) that if we could bypass an I/C it would be nice. Or have to go liquid to air instead, air to air is way to big (but Travis made it fit on his TB I6).
Ive just got my summer living situation setup, and Im going to be living in N Idaho, not Seattle so I dont know if my FI plans will pan out this summer or not. Im still looking to make it work, problem is if I rip my TB apart and need something Im screwed as I cant run 5min to a store, its a 15-20min drive and I only have my TB...
Only problem is being a poor college kid (as Im looking to buy rims, a new drop, and "other" performance mods:duh is gas costs a TON. Plus Im doing summer school Mon-Thurs and work Fri-Sun, so I dont have time to take vacation.
Coeur 'd Alene is about an hour south of Sandpoint, I ski at Schweitzer all the time.
Been talking to the 'rents and they are warming up to the idea of more performance oriented mods (as long as I pay for anything that breaks), so now its just a matter of funding and trying to find a backup car in case something happens and I cant drive my TB.
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