Need 8.1L info

[rs74]

I was doing some reading about the 8.1L's specs. In what years and what vehicles did the high horse 8.1's come out. It is said that they were built up to 550hp from the factory. I am assuming this was in the U-Haul trucks. There were marine applications that made 600hp.

What should I be looking at for the 550hp 690 ft.lbs torque engines. Did they really produce that much power?

[Clyde65]

From what I can gather and understand, the 8.1 is just a 7.4 with better heads.

read here..http://en.wikipedia.org/wiki/GM_Vortec_engine

also, even though it says LSX, it really isnt an LS motor.but it is a Vortech since the new heads ( I guess)

http://en.wikipedia.org/wiki/GM_LS_engine



8100
[edit]Generation
[edit]L18
The Vortec 8100 L18 is a V8 truck engine. It is a redesigned Chevrolet Big-Block engine and was introduced with the 2001 full-size pickup trucks. It is an all-iron engine (block and heads) with two valves per cylinder. It retains the same bore centers as the old 7.4 L big-blocks, but stroke was upped by 9.4 mm (0.4 in) to reach 8.1L (496cuin) for a total of 107.95 mm (4.3 in) bore and 111 mm (4.4 in) stroke. Power output ranges from 325 hp (242 kW) to 550 hp (410 kW) and torque from 455 lb·ft (617 N·m) to 690 lb·ft (936 N·m). Vortec 8100s were built in Tonawanda, New York. The Vortec 8100 is the engine used in the largest Uhaul, their 26-foot (7.9 m) truck. GM also sold the Vortec 8100 to Workhorse (now a division of Navistar) making it one of the most popular engine choices in gas powered Class A motorhomes during the first decade of this century. GM stopped installing big block V-8's in the Silverado HD trucks, when the GMT-800 series was discontinued in 2007. 8100 marine engines range from 400 to 600 hp (447 kW) and come with a stand-alone Engine Control Module (ECM). The last L18 was manufactured in December 2009.
Important differences between the Vortec 8100 and older big blocks include a changed firing order (1-8-7-2-6-5-4-3), a new 18-bolt head bolt pattern, different symmetrical intake ports, different oil pan rails and the use of metric threads throughout the engine. The fuel-injection system for the Vortec 8100 is nearly identical to that used on Gen III engines, right down to the fuel and spark tables in the ECU.[25]

[496bb]

I have an 05 2500 Burb with 8.1

As with any big block, it likes gas But I like the power it produces for a big heavy truck. A good tune (mine is Blackbear) really wakes it up too. They also were used extensively in RV chassis'.

Haven't really heard about "high-horse" versions. It would be very expensive to add heads and such to build a performance version, there is a company - Raylar I think is the name - that was making heads and such, but they are $$$$.

If you are just looking for a good FI BB to translplant, I think it's a good engine. But if I was trying to build a performance engine, I would look elsewhere - can do it cheaper with other blocks.....

[rs74]

Clyde, that is where I got my information that they have a 550hp engine. I am trying to figure out what they come in. If a guy could come across one of these it would be a pretty cool addition to a truck. I am playing with the thought of building a 67-72 one ton 4x4 dually.

[rs74]

I have a FI 454 out of a square body 91 one ton 2wd but they are lacking compared to todays LS and Vortec engines.

[bohmankid]

If I were to do a F.I. big block swap, I would grab a 454 vortec out of the 96-98 (99?) trucks. 8.1 are too expensive and hard to find. Not to mention expensive to build.
An 8.1 swap would be a lot cooler than a 454 vortec though