Found this 120kmi 305tpi/5spd car May 2005 in the San Francisco Bay area:



Set up a web page for it here:

'91 Formula WS6

Some of you here know about the project, probably most don't so here are some details. When I picked the car up it did not run well, surged and ran rich. Got that all handled, needed new injectors, radiator and a bunch of stuff under the hood. The 305 dynoed at about 200hp at that point, car competely stock. Since that time I had a March "street car" underdrive and 1.6rr put on it, that perked it up some rpms. Also had the front end rebuilt with a Spohn kit to get rid of the drunk 3rd gen sway! Put on the mandatory Global West Del-Alum bushings. I had some SLP 1-5/8 headers for it and small pile of goodies, some suspension pieces from Jason, some Konis from Sam, and Blaine Fab plans for an exhaust and subframes. Found a great deal on barely used Edelbrock TPI base and runners (from a forum member here), and staying 305 was the way to go..until... a 383 stroker was found in the CMC forum! Turns out this L98 stroker actually ran CMC in an '89 Firebird in the early early days when they were just trying to get bodies! Needless to say this CMCer was kicked out pretty quickly after the class got going and did not put many miles on the motor.

So, 383 and T-56 and Superram it is! I am hoping to do some autox (for fun) with this car if they ever get any venues back in my area. It has pretty much been eliminated with out an hour or more drive since 9-11. Also an occasional lap at Thunderhill. I want the car to stay stock looking, even using the stock wheels. Ed Miller over at TGO has an interesting Wilwood set-up for the front brakes which should fit.

I replaced the stock rear which interestingly enough had an aluminum drum rear. Due to some production issues GM "ran out" of the '91 4 wheel discs which normally come with the WS6 option. I found a '90s disc rear for it, THEN I decided to put a 383 in it!

SWEET 'Bird I love the 3rd GENS !!!

Great looking car and a very nice project

You'll love the 383... with a VERY, VERY! mild 388 I've got over 300 HP and 360 ft/lb TQ to the wheels with 300+ ft/lb from 2000-5000 rpm... it's fun to drive out of the corners

So what's going to happen to all those misc. 305 engine parts you bolted on the 5.0?

Thanks! After consulting with some local 3rd gen nuts and also Jeff Creech I decided on the LPE 219 cam. Jeff will be doing the tune.



The Edelbrock TPI base and runners are available! I will post some pics very soon and put them up in the classifieds section!

A guy who lives on my street has a blue '91 or '92 305/5-speed Trans-Am that looks good and seems to run well. Probably stock or nearly so. It does have black GTA wheels that look great. I keep waiting for a for sale sign to be slapped on it.

I wish you luck on that one! I looked a long time for this car in particular. I decided on it after the price on Firehawk #026 was not negotiable at all when I looked at it in person a couple years back.

I would probably be interested. Might help the B4C perform a little better. I will be hanging on to the original parts, though, for sure.

Gene, I'll be putting the Edelbrock stuff up for sale in a few days. There are a few extras in the box like a spare plenum you can port.

Nice toy, Julie! BTW, that fence in the background looks strangely familiar...

LOL Rob, Blaine Fab indeed!

Ok, the '91 Formula is "on deck" at Blaine Fab! Time to resurrect the thread!!! Alan has some SFC and exhaust wizardry planned, stay tuned!

Finally some cool Blaine 3rd gen SFC pics coming soon!

Interestingly enough I have a similar combo. I have an LPE 383 with 219 cam and the super ram. It sends punishment through a TKO600. I autocrossed this summer for the first time with the big motor, (ran 2 years before with the 305) and needless to say traction was a huge problem. I've got slicks now, just waiting for spring.... I'll also say the car is a blast to drive on the street. It is nasty at any RPM. The engine has a weak cylinder with about 70% blowby on #7, but it still put 330hp and 401tq to the wheels on a lean tune in 95* heat. I'm re-ringing it this winter and i'ts already been re-tuned, so this spring I'm sure it will be easily over 350hp and 430tp at the wheels, yours should be similar. Its a great street motor.

Alan has the specifics on the motor - it doesn't have the best flowing heads, but built to the hilt for what it is. The gentleman I bought it from, for a GRAND(!), produced receipts for $7500.00 worth of work and parts done at the local machine shop. I was very pleased it is an L-98 from a '91 F-body which helps keep it somewhat authentic.

I do realize traction will be a huge problem and am in a quandry as to what to do with the rear end of the car. Right now it still has the 3.42 stock rear in it. I would really like to put a Dana 44 in it with an LSD, but we know those are common as hen's teeth as our CMC Champ Jeff Burch likes to say. So I am thinking maybe a Strange 12 bolt or Currie 9" in the future. Whaddya guys think?

Moser 9" with Truetrack and order everything BUT the axles from them?

I'm running my original '86 rear with 3.23 gears which I converted to run PBR rear discs. I also swapped in stock 28 spline axles and a stock Zexel Torsen diff. I don't get enought traction even with my 315s on the back to damage the rear end. We'll see how autocross slicks do, but I still don't think I'll break the rear end. I KNOW it would not hold up to drag radials, but I think for road race/autocross use its plenty strong. I guess I'll find out for sure this spring.

Moser's axle problems are on the shafts where the shaft is also the inner race. Moser's 9" and 12 bolt both use the 9" ford wheel bearings so they won't have that issue.

Moser has lost my business due to their lack of customer support of their faulty axles they sent me. After talking to Alan Blaine I am going to try going with the stock 10 bolt, some Superior axles, a T2R and 3.73s. Since I am not a drag racer that may just hold up. If not, then plan B. Might as well see if this lower budget plan will work! I have some nice alloy 16x9.5 wheels for autox I have Kumhos on, we'll see! American Autox Series here we go!

It'll probably hold up just nice with slicks. You'll just get very good at repacking the clutches. I got good at replacing the clutch packs in our 86 SVO, even running in stock classes. The 9-bolt in our 85, I think, is just plain worn out.

<Diff Nazi> "No posi for you!"</Diff Nazi>

Nine bolt! Now there's an antique!

Whats wrong with 9-bolts, except for the fact that you can't get a decent diff for it? I love the fact that it doesn't use c-clips.

Well I hope I don't have to repack clutches, my Zexel Torsen diff is a torque biasing diff with gears in stead of clutches. Either way, I'm afraid with slicks I'll still be spinning the inside tire, I can sometimes spin one wheel now.... The fact is, I don't have $3000 to spend on a rear axle right now so the good 'ol 7.5 is just gonna have to work for now.

I think you answered your own question! I did own a 9bolt equipped car, an '89 Formula 350 (bought new). No complaints!

There's absolutely nothing wrong with a 9-bolt. It has served us very well. They are lightweight and strong. We have a 3.73 in ours. Trouble is getting parts. I think we have completely worn ours out. I'd rebuild it if I could get parts.

Yeah, by contemporary standards, it's an antique. But that's not a big deal for someone who keeps a '68 Cadillac running. ;-)

Project update - just about to get on the lift at Blaine Fab. Since then I made a couple decisions - decided LS1 brakes are fine for a mostly street app., going with an EB Miller kit and what is left from my LS1 brake set-up from my 4th gen CMC car. Late *braking* (ha!) news, I was able to obtain my old 3rd gen CMC car's rear end, a nice GM parts Dana 44 with a Detroit Locker. Hasn't been touched since I last raced it! A hearty thank you to my past and present CMC cars for their contributions!

Can't wait to drive this sucker! I'm gonna see how long I can lay down rubber marks on my neighbor's driveway (don't worry, we around here consider that a right of passage. Pretty kewl 'hood!).

I could give you a OD and ID on the shims needed to shim out the posi cones. When they get tired the cones sit lower and lower in the carrier until you've got less gear mesh on the spider gears and less preload, not a good combination. The cones may require machining to keep the faces from bottoming out on the outside of the carrier if they're pretty worn. Pretty easy to go through after you've done it a few times. I need to go through my spare, I've got a line on a fourth one with pbr's but I know I'll have to go to something stronger eventually. I'd like to play around with using a beefier spring on them to get some more preload out of it, I threw a washer under the springs, but I'm not sure how much that helped.



Congrats on finding a dana 44!

I'm interested in more 9 bolt diff info.