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| | | Forums66 Topics128,052 Posts1,055,729 Members48,426 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Dec 2004 Posts: 128 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 128 | I'm in the process of building parts to bolt a late model vortec 4200 DOHC inline 6 into my '51 GMC replacing a just broken in 292 that for sale.
The vortec makes 275hp in full emmision trim from the factory! So in hot rod trim its closer to 300HP.
The work packages to do the installation are: - Custom ford EDIS wasted spark crank trigger brackets and timing wheel designed to bolt onto the vortec with no mods. - Modified oil pan and pick up - change the throttle body from drive by wire to cable - exhaust system - engine wiring harness for the megasquirt EFI system. - custom engine mounts
IF anyone else is doing a swap and wants to get rid of the GM electronics I can add extra EDIS parts to my machine shop order. | | | | | Joined: Jan 2005 Posts: 164 Shop Shark | | Shop Shark Joined: Jan 2005 Posts: 164 | Oh my! My hat's off to you. I briefly considered this swap and decided it was electronically too complex for me.
Aren't there also issues with how the front suspension bolted to the engine? | | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | The only components that bolt to the engine is the front axle center section on the 4x4 versions. Shouldn't be an issue using the engine with the 2wd oil pan. You're gonna have to post some pix of the conversion, I know I'd like to see it installed. GM had talked about producing a crate version of this engine, similar to their Ramjet efi engines. They were supposed to have a self contained computer, only needing power and fuel to run. Never have heard the reason why it was never produced. 
Bill Burmeister | | | | | Joined: Jul 2006 Posts: 23 Junior Member | | Junior Member Joined: Jul 2006 Posts: 23 | How hard is it to find a bellhousing for this engine that will bolt to a T5 or 700R4? I know they make them but all of the 4.2's I have seen are mounted east-west and not north-south. | | | | | Joined: May 2006 Posts: 8,351 'Bolter | | 'Bolter Joined: May 2006 Posts: 8,351 | East-west north south? Do you mean front drive opposed to rear drive? The 4200 currently is only used in the Trailblazer and it's assorted clones. It's strictly a rear/4 wheel drive engine, longitudinally installed, no transverse. I don't know about the bellhousing pattern, but all the current versions are using the 4L60E trans, so I'd think it would be the same as the current smallblock.
Bill Burmeister | | | | | Joined: Jul 2006 Posts: 23 Junior Member | | Junior Member Joined: Jul 2006 Posts: 23 | I went to the dealer to look at one of these engines and the only thing they had was a Arcadia,New GMC Transverse mounted 4.2. All of the Older models had the 5.3 upgrade. If the standard trans used behind this engine is 4L60E then a 700R4 or any trans that will hook up to a sbc will hookup. All I need to find is flywheel and I will be able to use a T5. | | | | | Joined: May 2005 Posts: 145 Wrench Fetcher | | Wrench Fetcher Joined: May 2005 Posts: 145 | The 5.3 V8 was an upgrade from the 4.8, not to be confuse with the 4.2 IIRC. The Vortec 4200 (er, 4.2) is an all aluminum 24 valve I6 that has been available in the Trailblazer for a few years now. Part of the story with the good power number is in the variable timing exhaust cam. Lots of great info on inliners. http://www.inliners.org/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=3;t=000538 The bellhousing bolt pattern is unique to the engine family which includes an I4 and I5 engine. It is an impressive six. mv | | | | | Joined: Jul 2006 Posts: 187 Shop Shark | | Shop Shark Joined: Jul 2006 Posts: 187 | All '02 Trailblazers had the longitudinal 4.2...ALL. In '03 they offered the 5.3 in the EXT or extended Trailblazer. They sold so many that they're a dime a dozen now. I had an '02. Ran good but the power band was in the higher rpm's. Without emissions, it should scream and get decent mileage. Let us know how it works out. | | | | | Joined: May 2005 Posts: 145 Wrench Fetcher | | Wrench Fetcher Joined: May 2005 Posts: 145 | EFI-DIY, I'm curious why to went to the darkside for an engine management system. GM has some fully hacked 89-92 ECMs that give you reliabilty, DIS ignition, room for turbocharging if the future warrants it, etc. MV | | | | | Joined: Dec 2004 Posts: 128 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 128 | | | | | | Joined: Dec 2004 Posts: 128 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 128 | Darkside ....???
Hmm well for 1 I didn't have a factory harness or ecm. 2) I don't have the s/w to tune a GM ecm. 3) I've been using meagasquirt for 4 years now and know how to tune it. If it breaks I can fix it since the complete design is open on the web including s/w. | | | | | Joined: Dec 2004 Posts: 128 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 128 |
Last edited by KCMongo; 08/08/2008 4:21 PM. Reason: Switching Image to Link - http://www.stovebolt.com/news/2007/december2007/index.html#forum
| | | | | Joined: Jan 2019 Posts: 19 New Guy | | New Guy Joined: Jan 2019 Posts: 19 | In for update! What a bump back. Just started looking at the 4200's and wondering how much work it would be. was there actually a 2wd version? If so can you swap a 2wd pan on and that's that?
'49 3/4 Ton "It's hard to make a comeback when you haven't been anywhere" | | | | | Joined: Apr 2005 Posts: 7,440 Bolter | | Bolter Joined: Apr 2005 Posts: 7,440 | Well, the OP hasn’t posted in 4 years but he is still checking in on us. Maybe he can give us an update.
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
| | | | | Joined: Mar 2008 Posts: 1,775 'Bolter | | 'Bolter Joined: Mar 2008 Posts: 1,775 | The 4200 only has a front sump pan. Doesn’t matter if it’s 2 or 4wd. Mark, AKA, EFI-DIY has fabricated a rear sump pan and has them for sale. He is also working on getting flywheels machined. You can go to his website, emtechmotorsports.com for more info. | | | | | Joined: Jan 2019 Posts: 19 New Guy | | New Guy Joined: Jan 2019 Posts: 19 | Thanks Whitedog! Found the website and reached out. Awesome that he has this stuff. He mentioned he has one in his '51, sounds like it's up and running as well. I especially like the transmission conversion plate he has so we can run a more 'standard' transmission. I think the stock ones mated to the 4200 were a little iffy, seen quite a few Trailblazers, etc for sale with blown transmissions.
'49 3/4 Ton "It's hard to make a comeback when you haven't been anywhere" | | | | | Joined: Mar 2008 Posts: 1,775 'Bolter | | 'Bolter Joined: Mar 2008 Posts: 1,775 | I don't necessarily think the transmissions are the weak link. Most seem to go over 200K. When you compare that to the earlier 700R4's that may have went 50k, I'd say the 4L60E is pretty good. I want to say the 05 and later transmissions had some upgrades for more torque capability. One of the issues I have is actually finding a 2WD trans. Here in the midwest, I bet 90 percent of them are 4wd. | | |
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