Late Model 6 Swap? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

DirtyLarry · 10-16-2008, 07:56 PM

Man, as much as I embrace straight 6’s….. I have mixed emotions about the 4.2L. I have driven many rental TrailBlazers with that engine and have not been impressed. Personally, it feels like a gutless slug unless you drive it like you stole it and leave your toenail marks in the floor board every time you get out of it. I don’t feel like it would be worth the hassle of swapping in a 4.2L into anything when a Gen III small block has much more aftermarket support for swapping. Plus you would have to majorly rework the oil pan to work in an older GM truck.

The SAE Certified Power is 285 HP at 6,000 RPM’s! 6,000 RPM’s!!! You have to rat the hell out of this engine to get any power out of it. It is like driving a Mazda rotary engine. Not a good truck engine, which is why it was never offered in the GMT800 or 900 Silverado truck plateform.

The 4.2L engine controller is actually a nice Delphi MEFI-5 that has plenty of provisions for custom tuning providing you can find a tuner to remap it for you or unless you purchase software and learn how to do it your self which is a real PITA as I learned on my 8.1L swap.

The Delphi MEFI-5 is the same engine controller the new marine engines and GM Performance Part LS engine controller kit.

It would be a cool swap but not worth the hassle in my opinion. The entire GMT360 TrailBlazer and Envoy plateform was a heavy and low powered ill conceived package to begin with. The good news is production of the plateform and powertrain are done 12-23-08.

LuckyHenriksen · 10-16-2008, 09:05 PM

Thats too bad. I guess there was a reason that no one was doing it. BTW my Envoy Denali has the 5.3 and runs like a bat outta hell. Almost as fast as my GLI

Chris in Idaho · 12-28-2008, 11:11 PM

When people put TBI on their sixes, what intake are they using? I make adapter plates and am planning one for the sixes and am wondering what people would want. I can make one for the monojet, but I think the varajet would work out better. What do you guys think?

10-16-2008, 07:56 PM	#1
DirtyLarry Windy Corner of a Dirty Street Join Date: Jun 2003 Location: Pueblo West, Colorado Posts: 2,926	Re: Late Model 6 Swap? Man, as much as I embrace straight 6’s….. I have mixed emotions about the 4.2L. I have driven many rental TrailBlazers with that engine and have not been impressed. Personally, it feels like a gutless slug unless you drive it like you stole it and leave your toenail marks in the floor board every time you get out of it. I don’t feel like it would be worth the hassle of swapping in a 4.2L into anything when a Gen III small block has much more aftermarket support for swapping. Plus you would have to majorly rework the oil pan to work in an older GM truck. The SAE Certified Power is 285 HP at 6,000 RPM’s! 6,000 RPM’s!!! You have to rat the hell out of this engine to get any power out of it. It is like driving a Mazda rotary engine. Not a good truck engine, which is why it was never offered in the GMT800 or 900 Silverado truck plateform. The 4.2L engine controller is actually a nice Delphi MEFI-5 that has plenty of provisions for custom tuning providing you can find a tuner to remap it for you or unless you purchase software and learn how to do it your self which is a real PITA as I learned on my 8.1L swap. The Delphi MEFI-5 is the same engine controller the new marine engines and GM Performance Part LS engine controller kit. It would be a cool swap but not worth the hassle in my opinion. The entire GMT360 TrailBlazer and Envoy plateform was a heavy and low powered ill conceived package to begin with. The good news is production of the plateform and powertrain are done 12-23-08. __________________ Current vehicle collection: 1978 Chevrolet K10, 8.1L, NV4500, NP205 1989 Chevrolet Suburban, 8.1L, NV4500, NP241 1993 Chevrolet C1500 Sportside, TBI 7.4L, 4L60E 2001 Chevrolet K2500HD, Ext Cab, SWB, 8.1L, ZF 6 speed 2014 Chevrolet Impala LTZ 3.6L Vortec 8.1L because life is too short to tolerate underpowered vehicles Instagram Last edited by DirtyLarry; 10-16-2008 at 08:23 PM.

10-16-2008, 09:05 PM	#2
LuckyHenriksen Registered User Join Date: Oct 2007 Location: Sherwood Oregon Posts: 1,908	Re: Late Model 6 Swap? Thats too bad. I guess there was a reason that no one was doing it. BTW my Envoy Denali has the 5.3 and runs like a bat outta hell. Almost as fast as my GLI __________________ 1968 Yenko Chevy LWB 6.0L/TH400 3/4 Drop Senior Project Build Thread Here

12-28-2008, 11:11 PM	#3
Chris in Idaho Registered User Join Date: Nov 2008 Location: North, Idaho Posts: 68	Re: Late Model 6 Swap? When people put TBI on their sixes, what intake are they using? I make adapter plates and am planning one for the sixes and am wondering what people would want. I can make one for the monojet, but I think the varajet would work out better. What do you guys think?



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