Boosted 350 vortec, or stock 8.1?

[Christian Steffen]

Thats whats so great about America you have the right to disagree. I have spent hundreds of hours on engine dynos all the way back to the early 80's Have several NHRA records and was on the cover of Hot Rod Magazine in 2005. I know for a fact a header does not do hardly anything at 2500rpm to 3000 rpm. I only mention these things because I have been around awhile. Even if headers would work they need primary tubes to be extreme in length 36"38" which you cannot buy and very small in diameter 1 3/4 with a very small collector 2 1/2 in dia and bout 18 inches or longer in length. That's a custom hand built header at a cost of around $3000.00 dollars or more and I doubt you could find anybody to even want to build them for that. Any knowledgeable header guru would agree with this. Headers By Ed, Jack Davis Headers/Belanger headers.......These are the leaders in header tech. I own at least 5 NHRA records and in our day we ran 2 & 3 step headers before anybody even heard of them. I doubt you would even be familiar with any of this.........Mass produced shorty or store bought headers are worthless below 3000 RPM period. Now add to that fact that anything you can buy in a box are all junk. The flanges crack .pipes at welds crack and the bolts come loose, ignition wires are an issue and they wont last to long besides the ring and ting your going to hear as the torque of the engine is hummig. Pulling a trailer all day long will be a maintenance nightmare with the cooling and heating that happens. Your going to have issues and who wants to chase the problems. You wont see a 1/3 mpg increase.
Too finish this rebuttal to a guy who knows not to much.. every drag racer in the 70"s tried cams/headers/carbs/intake manifolds etc. Some of the best minds in engine building like Rehr Morrison etc tried everything. We pulled 40ft gooseneck trailers with 454 chevy duallys.....stock they got 6MPG and with thousands of dollars poured into research we all still got 6 MPG no matter what we did.
Most who had headers went back to Cast Iron manifolds and took the PIA headers off and got some peace and quiet as we got white line fever. It takes years of experience to learn these things and when we were all young the first thing we would say is lets put some headers on our trucks and after some experience with the headaches and non performance....they all came off. I have been building engines for 50 years and that has taught me some valuable lessons.

I will say that ~500-$600 will get you headers that seem to be pretty reliable, at least so far my JBA's have been completely trouble free, and the ceramic coating does a decent job at keeping heat on the inside.

 

[Tinman]

Personally if you're not towing a lot I would stay away from the 81 I have one but I put in my pickup they have a lot of lifter issues mine I put a new cam lifters rocker arms in and I cannot get the valve train to quiet down which jacks with the computer which is giving me trouble. I would go with a vortec and a tuned port system switch over to the 4:11 computer Make sure you got a 4L80 behind that thing and you're going to be knocking on 400 foot pounds of torque and be very nice better fuel mileage than that 81 when you're running empty

Look this over http://www.gmtruckcentral.com/articles/lt1swap.html

That was mine before the 81. When i get the $$$ together, the LT1 will get stroked to 383 and go in my 2001, and 81 will be sold. Yes i kept the motor ;-)

Just my 2 cents

 

[Tinman]

P.s SB's are cheaper to maintain $1300 in the cam swap for the 8.1 stock parts

 

[busaben]

Get a Junkyard 5.3 for less than $700, vs racing turbo kit for $1000, holley terminator efi to run it all $1000. $2700 would get you roughly 500 hp and 600+torque at the wheels, keep the 400 trans and sell the existing motor to recoup some funds. Add a cam and your up to roughly 600hp, 700ftlb

 

[sbctt]

Get a Junkyard 5.3 for less than $700, vs racing turbo kit for $1000, holley terminator efi to run it all $1000. $2700 would get you roughly 500 hp and 600+torque at the wheels, keep the 400 trans and sell the existing motor to recoup some funds. Add a cam and your up to roughly 600hp, 700ftlb

Agree with the LS Turbo. My current setup is a 98 Sub 2500 with a twin turbo LS6 from a Cadillac CTS-V backed by a Hughes built 4L80E. Small turbos and a torque biased cam delivers boosted power starting at 2000 rpm with a very flat torque curve. Has been very reliable and with the aluminum block is so much lighter than the factory big block. Expensive build though. Lots of tuning effort required. Before that I built a turbo charged 454 in a 98 sub 2500. Used a remote mounted turbo from a dodge cummins. That made great power too, was much less expensive and arguably more durable. The turbo solves the sluggish feel of the 454. Any boosted solution will require premium fuel so that is another consideration.

 

[letitsnow]

Thanks for the advice, guys. I am just dreaming for now, but am learning quite a bit.

 

[L31MaxExpress]

I love the cammed 8.1 in my Tahoe. I used the GM performance parts 454/502 HO cam in it. Nowhere near $1300 to cam swap.

 

[Sideburnz]

Go with a diesel with an upgraded the turbo system. A friend of mine has a 2010 Crew Cab Denali 4DR 4WD putting out 1135lbs. of torque @ 2200 RPM. He's had his entire setup bully Dogged though!

 

[letitsnow]

The only diesel swap that I would be willing to do would be a 12 valve cummins with a 5 or 6 speed manual. Not really interested in that though - would rather have an 8.1.

 

[Supercharged111]

The only diesel swap that I would be willing to do would be a 12 valve cummins with a 5 or 6 speed manual. Not really interested in that though - would rather have an 8.1.

2003 was an ideal year for Cummins motor and transmission pairing as far as donors are concerned. I believe it was a 24V, but the only year with a 6 speed and no emissions BS. A basic tune has you at over 700 ft/lb of torque and less rattly than a 12V. Marginally.