Good evening Y'all new guy here......

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01-24-2017
DangerDanNH

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Good evening Y'all new guy here......

Im Dan, a 36 y/o Iraq Vet planning out my first motor swap/upgrade. My truck is a '97 K2500 ECSB with a VERY tired 5.7 and 4L80E (315k origional miles) and a curb weight of 6200lbs. All out HP isnt much of a concern to me but would like a torque monster on a somewhat reasonable budget. Being new to the efi stuff would you recommend a 411 pcm swap or an aftermarket setup like F.A.S.T.? Havent decided between building a SBC 383 stroker or a SBC 427stroker. What are some building standpoints to consider as limitations for the 411pcm as in like cam size/duration, etc? Thanks for your input!
01-24-2017
Fast355

Quote:

Originally Posted by DangerDanNH

Im Dan, a 36 y/o Iraq Vet planning out my first motor swap/upgrade. My truck is a '97 K2500 ECSB with a VERY tired 5.7 and 4L80E (315k origional miles) and a curb weight of 6200lbs. All out HP isnt much of a concern to me but would like a torque monster on a somewhat reasonable budget. Being new to the efi stuff would you recommend a 411 pcm swap or an aftermarket setup like F.A.S.T.? Havent decided between building a SBC 383 stroker or a SBC 427stroker. What are some building standpoints to consider as limitations for the 411pcm as in like cam size/duration, etc? Thanks for your input!

As cheap as you can get one, find you an 8.1 out of an Express/Savanna van or a GMT400 HD truck and go big block. I picked up one from an Express cutaway party bus with 80K on it to swap into my Express van in place of the small block but it won't fit without cutting the floor and firewall. Putting it into a G-van instead. Was going with a SAS 4x4 conversion on the Express but doing the G-van instead. A big truck like that needs big torque numbers and a big block is the cheapest/easiest way to get it. I doubt you could build a 383 or 427 short block for what you could find a complete running 8.1 swap for. The Vans/Avalanche and Suburban 8.1s were all backed to a 4L85E. I am building an aluminum head, roller cam 406 with coil per cylinder ignition, marine intake, and drive by wire for the Express. Overall the 406 is going to cost me 2-3x what the 8.1 swap will cost me in the G-van. 8.1 is getting a GM performance parts 502HO cam or a 425 HP Mercruiser cam. I actually have both cams. Really thinking of going with the 502HO cam so that I have the traditional big block firing order and sound.
01-24-2017
DangerDanNH

Re:

Ya the 8.1 was something else I had considered which is basically a 496bbc. Dont get me wrong even with the tired 350 she still moves with pep considering my compression sucks due to.TERRIBLE leak down lol. As far as the 411 goes how much cam can the pcm handle (looking for noticable off idle) but not race lope type sound in the build.
01-24-2017
Fast355

Quote:

Originally Posted by DangerDanNH

Ya the 8.1 was something else I had considered which is basically a 496bbc. Dont get me wrong even with the tired 350 she still moves with pep considering my compression sucks due to.TERRIBLE leak down lol. As far as the 411 goes how much cam can the pcm handle (looking for noticable off idle) but not race lope type sound in the build.

I had a 215/220 @ .050 on a 114° LSA in my Express with Etec 170 heads and it fired right up and ran on the stock tune.I put an 0411 in my brothers 1999 Tahoe that has a 218/218 @ .050 flat tappet cam on a 110° LSA in a 305. The black box took a ton of work just to get it to idle and run decent. It started right up on a nearly stock 305 Express tune for the 0411 and actually ran fairly well.I ran a TPI 383 engine in my old G-van with a 232/240 @ .050 roller cam cut on a 110° LSA and the 0411 ran it very well. My buddy has a big cam in his 6.0L running an 0411 and it also ran well after some tuning.If you even considered the 8.1 go for it. The GM 502HO cam is a very nice cam upgrade and just about any long tube header for a 454 in your truck will work on the 8.1. The 8.1 has the same exhaust ports and bolt pattern as a 454 only difference is it is a tall deck block vs a short deck on the 454.
01-24-2017
lionelhutz

The '0411 will handle a cam much larger than you'd ever want to use if you're truly after building a low end torque monster. Also, cams big enough to start producing a noticeable idle lope will start to hurt the low end torque you posted you want.
01-24-2017
DangerDanNH

Ya I know. Just want a noticable ile difference but not the barely able to idle lope lol
01-24-2017
Fast355

Quote:

Originally Posted by lionelhutz

The '0411 will handle a cam much larger than you'd ever want to use if you're truly after building a low end torque monster. Also, cams big enough to start producing a noticeable idle lope will start to hurt the low end torque you posted you want.

Not really true....You can cut a cam on a 106 or 108 lsa and it will have a choppy idle but the intake valve will close earlier helping keep the cylinder pressure you need for torque. I have run the old Crane 274H06 cam in a fairly stock 8:1 350 goodwrench motor and it still made very good torque down low. The 395' marine cam is cut on a 109° lsa and has noticeably more chop than the stock Vortec cams.