Poncho72

iTrader: (1)

I'll try to make my question as short as possible. i am trying to decide between these 3 engines and according to this production chart:

https://ls1tech.com/forums/conversio...ification.html

it seems that the L33 would make the most sense. i'm shooting for the 350 to 400 hp range, and the alum. block would free up quite a few pounds/dollars. on the other hand the the LQ4 or LQ9 would give me the same (stock) power, cost a little more on average, and are iron blocks=little more weight. i'm trying to strike a balance between power, weight, and gas mileage. i originally was set on a 6.0, but after doing a little more reading i'm torn.
this is a 72 Trans Am tribute build that will see mostly fair weather spirited driving, no plans for track time, and will be coupled to an 01 T56 that has a Stage II build. Pros? Cons?...all input would be appreciated.

cobalt964

l33; 310-330hp depending on the source you read. around 420lbs fully dressed. great potential for reliable 400chp build on the cheap. depending on miles likely $600.-1800.00 for stock engine usually.

lq4; 300-310hp gen 3 depending on years. around 510-520lbs fully dressed. easy reliable 400chp. likely a little more coin than the l33. good foundation for future upgrades. depending on miles and yr likely $1000.-2000. for stock engine usually.

lq9; 310-335hp gen 3 dependin on yr and model. around 510-520lbs fully dressed. easy reliable 400+hp. more coin than the l33 or lq4 but good foundation for future upgrades. depending on miles and yr likely $1400.-2500. for stock engine usually.

just ballpark guide. im sure others will chime in. modification prices will be similar for which ever motor you choose as they all share similar architecture. have fun in your build.

ls1nova71

iTrader: (4)

Since you're building a "fair weather, spirited driving" car, I wouldn't worry too much about gas mileage. My vote would be 6.0, since they are strong reliable, can make a lot of power, and fairly easy to come by. Not to mention when someone asks what's under the hood of your TA, 6.0 is going to sound better than saying its a 5.3.

Poncho72

iTrader: (1)

i knew the stats. on all of them, and i'm way past the bragging rights stage. i am trying to get a gauge on what the extra 100 lbs lost because of the alum block will gain me. i do want the 6.0, but what if..... maybe the L33 adds improved handling, being lighter, with about the same performance as a 6.0. i am thinking with the right cam swap, full length headers, and a good exhaust system, the L33 would be a very potent street powerplant, especially in front of an able 6 speed. any other thoughts?

JJR67

Any of the LS engines work. I did a 6.0 Lq9 topped with LS3 heads an intake. I have not had it to the track yet but it seems to pull harder and longer than the 406.

BigEd_72455

iTrader: (7)

Why not just get a 4.8 or 5.3 and toss in a cam/springs and a set of 799 heads?

Same power, but could amount to less cost, depending on the 4.8/5.3 mileage. Some folks just have 6.0 on the brain and it never goes away, despite the rising cost of them. There is not much power benefit, despite the significantly higher cost of the engine.

Local yard to me has 4.8 or 5.3 in the 4-500 range, where the 6.0 runs 1200+. That is including harness and computer. Lower mileage gets the numbers up in a hurry.

gofastwclass

iTrader: (2)

I agree with BigEd on this one except if you are swapping heads...

From the weight penalty angle... The things I've read / seen / experienced say the aluminum vs. iron block debate is closer to a 65 - 80 pound difference, all other variables being equal. Most of that could be gained by moving the battery, using a dry cell battery, removing the AC/heat and insulation, etc.. For this reason, it's hard for me to spend the money to buy an aluminum block just for weight savings in a street car unless I'm in an ultralight vehicle (MG, Miata, etc.). The other tipping point would be if I spent a lot of time at the track where weight is a larger disadvantage.

Part two of my weight challenge... I'm willing to bet money that ANY fully dressed Gen III / IV engine will weigh less than whatever came out of the car originally in the like condition. In my opinion that fact alone makes the whole engine weight debate moot.

Personally, I would look at upgrade paths for each engine and it's intended use. Are you going with a cam only, heads and cam, forced induction or spray? If you are buying aftermarket heads in the future, the 5.3 block's smaller bore size limits your choices substantially.

cobalt964

many built up l33 builds putting out 430-450chp so if agileness is your goal that could be a contender from that angle.

Poncho72

iTrader: (1)

thanks for the input guys. i know that most base the "weight loss" comparability to the SBC, but a fully prepped Pontiac can be 40-50 pounds heavier than that, closer to a decked out BBC. the A6 AC compressor alone is a log. i have totally stripped the front of unnecessary components such as the HVAC system, and the VA unit weighs a fraction of factory components. i know that all this is jibber jabber for a "spirited street car", but i'm shooting for all i can get without breaking the bank, and having a little fun planning and executing. still undecided, so it may come down to the best deal.

BigEd_72455

iTrader: (7)

here is my 5.3L LM7 engine at its current stage.

I plan to remove a few more things from the truck and finish swapping it over to carb'd. To me (this is my opinion) upgrades will be easier to do and not as costly.



This is the 750 DP that is going on it...

cobalt964

incidentally I have a third gen Camaro im planning on putting a hot l33 into. so power to ya.

Poncho72

iTrader: (1)

as stated before , i'm still undecided and wanted to pick brains of those that have been there and done that. i never saw such a detailed LSX breakdown before i ran across that chart. Sorry BigEd, i am way past carbs. i am an efi junky so much that i am working on a megasquirt unit for my 66 gto that looks like a quadrajet on the outside. i continue to read posts here, mostly builds and what members are brainstorming and problem solving about. that L33 sure has me swaying back and forth against the 6.0. i still have a lot of time as my tub is still bare on the rottiserie, blasted, and installing trunk pan and cowl section now. suspension, subframe, and body mock up with a few custom body tweeks are next. then i'll really need the engine.

1981TA

iTrader: (7)

2nd gen f-bodies are very nose-heavy to begin with, so almost anything can do to reduce weight up front would be a change for the better, especially if you are gonna try making your car handle well. I'm a bit biased (check my signature block), but I'd go the aluminum block route. The 5.3s can take a lot of abuse, and aluminum versions can be found way cheaper than their bigger displacement brethren.

Poncho72

iTrader: (1)

agreed 1981TA, i am trying to get the front to rear ratio a little closer. i have the Hotchkis Stage 1 package, thought about ridetechs 4-link with coilovers or air ride but i can't justify the cost for a street car.... YET.

cobalt964

famous last word "YET" lol

BigEd_72455

iTrader: (7)

hey Poncho72, what about just installing air shocks for now? Local napa priced a set to me for less than $100.

May not be all super fancy and all that crap, but you can then decide on which ride height you want to go with by looking at the different positions.

BigEd_72455

iTrader: (7)

IF you are trying to make it look like a carb, are you going to use one of the carb intakes? Like mine? I ask because I bought 2 sets of intake gaskets for these edelbrock manifolds in case someone needed a pair but forgot about the added $6 shipping to get it to them, when an oreilly's will get them the same gasket set for $23 plus tax.

Oh well, I have an extra set if I ever go to the super victor and the 4500 dominator which wont happen.

And yes, the megasquirt is sooo much easier to get tuned because all you need is a cable and a laptop and you can do it yourself with the included software, not to mention it can be swapped to another vehicle and tuned in a short while.

1981TA

iTrader: (7)

here's an early pic of my engine with the Holley Commander 950 on it before I switched over to carb. It ran pretty good, but I think the newer aftermarket EFIs are light years ahead of it now.

BigEd_72455

iTrader: (7)

Yeah, some of the stuff they have out now is just mind boggling for how they get that stuff done! but still yet, even using the LS3 intake and the holley system that is built right onto the fuel rails (I think its Holley) is just cool as hell. But the damn price tags are INSANELY HIGH

Poncho72

iTrader: (1)

this is NOT a poor mans arena, but if you are in the business a lot of horse trading happens. My Dad had an auto repair shop for 30 years so i have gotten a lot of cars/parts for cheap or free. he's been retired for many years now, i chose another profession, and reserve my wrench time to my own rides. i am telling my age , but i can remember paying less than $200 more than once for 1st gen Camaros (ok maybe 500 for an RS or SS maybe). The LS trend and paying the cost for technology is the car world today... oh well. that airshock idea would be great if not for the horse and buggy ride quality you get from it. i know cuz i had a 71 TA with air shocks, it either bottomed out and broke shocks with low pressure, or rode like a wagon with higher pressures, OR very bouncy. Dad had a Holley Projection setup on a 454HO crate engine (similar to your Commander 1981TA), but we never got it to be a consistent performer. Summit finally "bought it back" from him, and agreed that in 1997 aftermarket technology had not progressed as far as tunability and working the bugs out. it kept killing the chip and board.