# Engine Build Photos



## lars (Sep 28, 2004)

Here are a few shots of the latest 463 build-up I just finished. It's a mild street/strip engine with a solid flat tappet cam, ported iron heads with Ferrea valve components, Pontiac H-O aluminum intake, forged TRW pistons running compression at 10:1, Hooker SuperComp headers, and a curved HEI distributor. Carb in these photos was a Demon 750, but it has since been swapped out for a Mighty Demon 825 Annular Booster mechanical sec.









This is the installation in the Formula Firebird in process. Tranny is a Hurst-shifted worked-over M-40 with a 3500 stall converter putting power to a 3.73:1 limited slip rear. Car runs very strong.


----------



## 05GTO (Oct 6, 2004)

Sweet!


----------



## lars (Sep 28, 2004)

And just for fun, here are some of my other GTO toys:


----------



## tetonchef (Apr 22, 2007)

*interested*

lars- i am thinking of using a similiar rear end set up in my 67' G.T.O, i believe it is stock right now w/ 3.08 gears. what kind of posi unit did you go with? i run a 60 over 400 c.i.d. block w/ a 455 crank, it is very strong but definately a street driven car. ive heard that 3.73 gears are very good on the street. what do you think? thanx -scott


----------



## lars (Sep 28, 2004)

I used the stock factory posi unit. The aftermarket units are very good, and drop right in place. Keep in mind that your 3.08 carrier cannot take a gearset steeper than 3.73:1 without the use of a spacer or another carrier (I prefer not using the spacers).

The 3.73 setup is nice for drag racing and a little "stoplight grand prix" action. But you do get some pretty elevated rpm out on the highway, so they're not good freeway cruising gears. This particular car redlines at around 115mph since I don't have overdrive with the M-40 tranny. We're thinking about doing a Kiesler 5-speed setup on it to get the cruising rpm down a bit and going with a 3.23:1 rear. If you don't do any serious racing, the 3.55:1 is a very nice setup. For street driven 455s, I have had very good luck using 3.23's due to the torque of the big engine.


----------



## BobG (Dec 20, 2006)

Nice collection, Lars.

Now ... what do I do with a 3.90 Non Safe-T Track ??? any way to turn it into a Limited slip?


----------



## lars (Sep 28, 2004)

Very easy to make that 3.90 open perfrom like a limited slip. Simply install an airbag in the passenger side rear spring and run about 15 to 20 psi of pressure in it. This will pre-load the right rear spring, and it will prevent torque from pulling that side of the axle off the ground. You will get the same traction on both wheels, and the car will act and launch exactly as if it were a limited slip - you will spin both rear tires exactly the same. It will dramatically decrease your 60-foot times.  The only drawback is that the car will ride "crooked" when you have the air in the bag, so just pump the bag up when you're racing or when you go looking for trouble on Saturday night. ...and here's a tip if you're into street racing: Watch out for the guys who have cars with the right rear riding higher than the left.... that's the guy who has done some suspension work to plant that right rear tire during launch, so he's a serious racer...


----------



## jpdog357 (Feb 27, 2006)

Lars,

How difficult is it to put a whole new limited slip diff in, like an Eaton or something similar?

I am thinking this route and probably will get my local shop to do it but I am wondering if there are any major pit-falls.

Thanks,

Jason


----------



## Twizted (May 23, 2007)

Nice Goats man. Have ya took tha Formula to tha track yet? What it run if so?


----------



## lars (Sep 28, 2004)

jpdog357 said:


> Lars,
> How difficult is it to put a whole new limited slip diff in, like an Eaton or something similar?
> 
> I am thinking this route and probably will get my local shop to do it but I am wondering if there are any major pit-falls.


The aftermarket units work well and go in nice. With new gears, you do need to set up the pinion depth with a pinion gear depth gauge, and a lot of shops don't have one... they set it up in the ballpark using Dykem on the gears and trying to read the pattern. Find someone who actually has a depth gauge and knows how to use it in order to get a good setup that will run quiet and reliably.


----------



## lars (Sep 28, 2004)

Twizted said:


> Nice Goats man. Have ya took tha Formula to tha track yet? What it run if so?


The car weighs 4200 pounds with driver, and runs consistent 12.6's. The engine dyno'd at 539.4 hp at 5800 rpm, and put out 583.7 ft/lbs of torque at 4300 rpm.


----------

