jfmoore79

New guy here...and new to LS builds in general.

I'm on the fence with whether I want to go LS in my 72 Buick or stick with a big block build. My goal is a driver that will run in the 11.5-11.7 range on motor. If I go LS I will more than likely install a nitrous setup. The biggest concern I have is how well I can overcome a heavy car with a motor that specializes in top in power. I don't want the car to die out of the hole. I also don't want such a large cam that I can cruise. Also, Im pretty sure that I can make more power and be more reliable for less money than the Buick build.

My first thoughts were to go all forged 408 cubes with LS3 heads. Obviously with an intake (Victor Jr?) and carb (750 HP?)

Am I even on the right track? Any suggestions? Realistically how much should this cost?

Thanks guys!

ZONES89RS

iTrader: (25)

If you have the cash for a 408 build, it will get the job done. But a custom cam from Martin with some ported 317 heads would do you well for low end power in the cruise department and low end torque.

streetknight2

iTrader: (10)

I'm not in any way trying to discourage you from a LS build, I love them and have a few.

BUT, in the ET range you're wanting, I think you may be better off with a 455 Buick. I ran them for years. Stock bottom end, Stage 1 heads, C113 cam, B4B intake and decent converter I ran 11.50's in a full weight (3800 #) 72' Skylark

I've got a call into a buddy now, he has a Skylark with a 6.0 in it that ran 10's in a Mustang, not sure if he's taken it to the track with the LS setup. I'll report back lol

streetknight2

iTrader: (10)

His ran 7.50's 1/8 mile so it was real close to my Buick motor.

ZONES89RS

iTrader: (25)

My buddies Malibu with. I weight removed(79 model) went 7.3 with his tune and a 670 vac sec carb. So there is plenty left in it with a larger carb and my tuning.

jfmoore79

This is why I'm still on the fence! If I stick with a similar 455 build I can probably get close for the same cost to build an LS BUT if I want anything faster such as low 11s or the ability to use nitrous I really have to build the Buick up. Using forged bottom end, block and lifter girdles, and aluminum heads gets the cost over $10K+!

Decisions, decisions...

newschool72

iTrader: (12)

That's a tough one. What do you weigh? My set up works fantastic in a 3500lbs car, running mid 11s at 118mph with a tire spinning 1.875 60 ft. It also makes enough torque to blow the tires off at a well prepped track with a 2800rpm stall on drag radials. Im sure in my 3485lbs car, its a low, low 11 sec setup with traction w the 2800 stall and 3.42 rear gears.
Im running a crate LS3 with a cam that me and Tim at Bullet Racing speced out w 220-230 at .050 on a 108+4 w 629 lift on both sides. That and a GMPP dual plane intake and 1 7/8" long tubes rounds out the setup.
The biggie for me on this engine is, I can cruise easily at 55mph and 1750rpms with the converter locked ,up and down the rolling hills where I live. It pulls down at that RPM without a hint of lugging. It also pulls enough vacuum to run my big power brakes that need 16" of vacuum to run right. It will buzz straight to 7000rpms without any seat of the pants drop off.
With more cubes, in your Buick, That formula should easily get you to mid 11s performance, without taking any low rpm cruising ability away.
Its not the popular choice on cam design or the intake choice, either, But the numbers don't lie. This combo will give you a cake and let you eat it too, period.

6D9

iTrader: (1)

Another option is a 489-496 stroker BBC. Tons of torque and a set of factory cleaned up large oval ports heads cheap. No aftermarket heads needed. Here is my buddies combo that has only been to the track once. Its a all steel 68 chevelle that tips the scales at over 4100lbs with driver. Here is the combo:

496 bbc....10 to 1
781 large ovals...mild port work...2.19/1.88 valves
RPM air gap dual plane
Holley HP950 street
241/249...625/625...110 hyd roller
1 3/4" mid length headers (needs larger+longtubes)
3" exhaust
TH400....2400 stall
3.73...28" DR
Mech fan/power steering/power brakes

Only at track once went 11.8 at 117.9

jfmoore79

Im guessing the car withme in it is close to 3800 pounds. Probably using a 2004R tranny and i have 3:42 gears. I like what im hearing about the LS3

No offense but putting any non buick engine is heresy in the buick world....and a BBC is the greatest sin! I just couldnt do it

fly442

if you got the money a big block will work but a 496 is not a cheap motor.But ls3 also is not a cheap motor.

6D9

iTrader: (1)

Lol...its ok for a LS but no BBC?? I love LS stuff but for heavy rides like yours you gotta love big cubes. Mild gears and mild stall...low rpms...still run hard.

fly442

yes i love big cubes.My old 1966 442 had a 496 bbc and went 6.40 in eight.But i sold the big block as it was hard on driveshaft,s and now I am getting older and not racing just going to put it on the street.

newschool72

iTrader: (12)

Its a bad a$$ engine for how mild it is. A year ago , I would have called someone crazy to make the claims I made above, but its the real deal. I cant find the link, but surf up D&A on the engine masters challenge and check out the 409 (stroked 6.0) they built. Its one of the biggest influences on the way I put mine together. 525ft lbs at 2500rpms! 575 ft lbs at 3500 ! and peak power at 5900.....595 HP !
The formula is pretty simple on paper and I proved the formula doesn't have any real tricks to work. I went with the same IDEA on camshaft and used the stellar GMPP dual plane intake and LS3 heads. Power is always right there, from off idle to 7000rpms. If you have the funds, I would do a 416 with the same formula of low 220s at .050, aggressive lobes w lifts in the 600 range to take advantage of the flow on the LS3 heads. D&As cam in the 409 had 224 at .050 on a 108+6 LSA. I didn't want to get that aggressive on lead, so I did 108+4 and it works great. The GMPP dual plane can move all the air you will need at upper RPM, BUT the long runners make for some great torque down low, as you can see from D&As TQ #s.
I hope you go this route because I think it will fly in your Buford and not take away a bit of street drive ability. Good Luck !!

jfmoore79

When I search D&A and pull up the specs for their build the numbers are different...458 ft-lbs at 2500rpm, 487 at 3500rpm, and peak of 522hp at 5700....

Maybe Im looking at the wrong build of theirs

newschool72

iTrader: (12)

Yes , wrong build. The one that's on LS1 tech is their odd ball small cube build. The build Im talking about is on their 409 build that was in the engine masters challenge. It also had a feature in Popular Hot Rodding mag. That build you are looking at is some weird 334 cid build they did. That build was the only one Andy could find the #s on a while back when we were discussing the GMPP intake.

newschool72

iTrader: (12)

http://www.popularhotrodding.com/tec...s/viewall.html
Here you go. Enjoy!! My numbers were off slightly, but my memory isn't what it use to be and its been a couple years since I looked at it. They are 533 at 2500rpms and 581 ft lbs at 3200 max TQ. HP was 588 at 5800rpms. Look at the torque curve. I feel at same thing with my abbreviated , much simpler build. Over 500ft lbs from below 2500 to 6000rpms !!! That's a special engine combo ! The secret is short duration, a lot of lead with aggressive lobe profiles to get high lift numbers, LS3 heads to carry the HP and TQ at the upper RPM range and the GMPP dual plane to flatten the torque curve. Also notice the peak HP is at 5800rpms , BUT it still has 564 HP at 6400 rpms ,where the pull stopped. It just keeps on going in the TQ and HP curve. No need for deep gears , high stalls, or a super light car to make power you can use everywhere.

jfmoore79

Thanks! Ill do some more research and let you know what route I decide to take.

speedtigger

iTrader: (16)

I know a thing or two about heavy Buicks. You can see what I chose. I am quite happy with the results.

jfmoore79

Speedtigger, Ive been following your progress for some time on here and on V8Buick...you were one of the main reasons I started down this path.

My ultimate goal is mid 11's on motor and anything on the bottle is a bonus.

Like I said before, Im still planning out my build and doing research on things but I really appreciate all the help Ive found on here. The idea of a dual plane intake is something I had never thought of since most magazine builds are strictly after peak HP numbers. Flattening the curve should really help the car be more streetable.

fast89stang

iTrader: (2)

6.0 and never look back. I know even a LS3 here just sold to a customer for 5 grand, brand new. I gave 400 for my 6.0 with L92 heads, and I love it.