Battle of the Engines.

[Tailssideup]

Hey all, long time lurker, first time poster. I have recently been offered a Chevy Small block to put in my 1980 Pontaic Sunbird. I am looking towards road course racing, and I was wondering if the Buick 231 V6 I have in it now would be a better choice or not. And if anyone can give me suggestions on helping with the swap or making the car handle better I am open to any suggestions.

[Bacchus]

It depends on what you want to do and what class you want to run. Most sanctioning bodies will put you in full modified if you switch from the stock V6 to a V8, and then you are running against vettes, vipers, 911s, and such. If you want to keep it to a more competitive class, I suggest keeping the V6 in. Some people here that have a lot more road racing experience than I can chime in.

[bugdewde]

Typical Autocrossing rules will put any engine swap vehicle in the modified class..........
You'd be competeing with tube buggies and purpose built vehicles and it would be very difficult to compete with a relatively heavy stock bodied vehicle such as ours.

My all aluminum Buick 215 V8 (320 lbs) ..... the only mod I have except for the 5 speed tranny.... puts me in the modified category. No way to compete in that group. I hope to just do it for the fun of it......... knowing I have no chance of ever placing or winning.

[cosvega76]

I would agree. I was in the A Race class with my Vega, I didn't have a chance to be competitive. I did have fun running it, though! It's fun having people come and check out your car in the paddock. An H-body is an unusual sight.

I now have a '92 Corvette for autocrossing. Maybe the Vega could have done this well with some more tweaking, but the Vette is incredible right out of the box. I won my class championship last year.

Keep the V6 - the car will have better balance, and you'll have a chance at being competitive in your class.

Chuck

[monzamess]

If you plan on doing official SCCA events, you can find their rules online:
Road racing: http://www.scca.com/Club/Index.asp?reference=gcr
Autocross:
http://www.scca.com/Solo/Index.asp?IdS= ... 050|070&~=

One school of thought, which I respect, is to make your car safe but otherwise leave it stock. Then drive the crap out of it and focus on improving your skills.

With that in mind, if you look at the rulebooks (and someone can correct me, PLEASE) you might come to the conclusion that it won't matter much if you mod your car because you won't be competitive with a stock or close-to-stock h-body.

For example, in Solo2 stock, V8 isn't classified, and other h-bodies are in HS. Stock h-bodies probably aren't competitive in HS--tiny cars that turn and accelerate better dominate this class. Next, to the prepared classes--the V8 and V6 are in "E prepared" while the others are in "F prepared." In the prepared class you can generally mod your car with factory options (i.e. you can turn a V6 Monza into a V8 ). In EP you'll compete against the Camaro SS among others. In FP you'll compete against tiny, nimble cars that accelerate at least as well as a 4-cyl h-body.

For road racing in SCCA, any cars older than 10 years can't compete in the stock class, so again, you would expect to have some mods on your car to compete in one of the non-stock classes.

My advice is to do what you want with your car, make it safe, and go practice and have fun--even if you lose to Corvettes and purpose-built tube-frame cars, you can still track your own progress and improve.

If you really want to be competitive in the SCCA you'll wind up buying a different car. Someone please prove me wrong.

[rpoz-29]

According to the 2006 rule book, a V-8 powered H-body would be in F/Stock under the "V-8 sedans, pick-ups, and sedan derived convertibles NOC" catch all. The V-6 and 4's (including the Cosworth), are listed in H/Stock. The V-8, and V-6 both run E/Street Prepared, while the 4bangers run in F/SP. The V-8 and V-6 run in C/Prepared, while the 4's run in E/P. I'm in a similiar position with an Olds Starfire road racer I bought a year ago. It has an even fire V-6 (machined, and ready for re-assembly), in the hatch. I want to autocross it, and am looking at C/P, or E/Modified. I know it won't be nationally competitive, but it should be fun locally.

[rpoz-29]

If I were going to use the car for Open Track type events, I would prefer the V-8 to the V-6 if only because the parts are more plentiful. The V-6 had a serious oiling problem under hard cornering. If you intend to autocross this car, as monzamess said, make it safe, keep it stock and learn to drive it. In stock, you can install a larger front sway-bar, aftermarket shocks, a cat-back exhaust, and any "R" compound tire you can get on your stock sized (+/- .025 " offset), wheels. I ran a '73 Vega from 1975 until 2003 in a variety of classes. I managed to win a couple of state championships with it in H/S, but once the Civic si, and then the Mini were dropped to H, the party was over. What specifically do you plan to do with the car? I'll be glad to offer any advice/share any experiences I can.

[NixVegaGT]

The SBC is heavy by comparison to the v6. You'd have to think about weight distribution in your equation. If I was going to use a SBC I'd want to mount it as far back as possible to help this and get aluminum heads and intake to reduce it's girthy qualities.

The v6 on the other hand has better possibilities for moving weigh distribution to more 50/50-55/45.

Just something to think about.

[rpoz-29]

Although it is a concern, I wouldn't worry too much about the weight difference of the engines, (about 190 pounds). In SCCA Showroom Stock racing years ago, the 305 V-8 Monza's did very well. As long as the suspension is engineered for the additional weight, you should be okay.

[marco_1978_spyder]

the solo II state champion in florida in around 1979/80 was
a 79 sunbird coupe with a 305.

[Fastmax32168]

When my buddy and i autocrossed back in the late 70s he had a 4 cyl monza and I had a 305 powered spyder. His car was consistently faster than mine no matter which one of us drove which car. Autocross is definitely not all about motor.
Roy

[cammerjeff]

You can make the V-6 go with some basic modes, the good news for you is you have an 80 so you aleady have the High port heads (79 & later) & matching exaust manifolds that flow much better than the 75-78 manifolds.
I don't know exactly what mods the sactioning body would allow in class, but a rear gear change to 3.42 or 3.73, and a higher stall torque converter, will make an imediate performance boost, if you are allowed to up the CR to 9.5 add a 4 bbl intake, either after market or from a 4.1 buick V-6 (or add a 4.1 V-6 with the same modes) get a modified Q-jet for the stock look, a came change and if allowed
ported heads, and you should be lookin at 230 to 250 HP.

I have done most of those mods with the exeption of the CR boost, and added headers to my 78 Sunbird wagon and have managed to get the 1/4 ET down to 14.6 from 18.2 (the 14.6 was according to a friends G-tech, the 18.2 was at the track) I am planning on building a 4.1 V-6 short block for the car this winter as the stock 3.8 is getting alittle tired with 88,000 miles on it.

But remember if you do plan on moding your buick engine, a MUST DO is the oil system modes, high pressure? high volume kit to the pump, and if you rebuild the engine you should have the main oil gally passages enlarged, and a baffle installed in the pan. There are several good books on moding a 3.8 most dating from the early to late 80's, The GN croud can help with the low end info, but there top end mods won't really do the best job on a NA engine.

A off topic Question on your 80 sunbird, does it have pwr steering? And if so, does it have a quick ratio box? I was
amazed that my 78 wagon came with a 3 turn lock to lock box, the same box that came in a standard T/A, and the 3 parts wagons I have had, 76 Astre, 78 Sunbird & now a 79 Sunbird all have had the same box!

If you have any questions feel free to PM me.

[Tailssideup]

My car has power steering, just to let you all know. But now I have the V8 in my hands and have decided to use it. I have already drove the literal crap out of this thing, I put about 12000 miles on it in the year and a half I had it. I really learned how it reacted in cornering and other such conditions. I plan to mildly build this V8 and put it in the car and learn how it reacts then. I would not mind at all being in a class with corvettes or mustangs, personally it would make me feel as the underdog and try harder to win. Thank you all for the suggestion though. I am also thinking of upgrading the suspension to all around QA1 coil overs. Does anyone have input on these? Would it be a good modifacation? Also I have a Buick Skyhawk as a parts car (Then giving it to my buddy who is putting a 400 Cubic inch Pontiac in it and racing it so it wont go to waste) I am taking the rear sway bar from it given that mine did not come with one. So hopefully I will greatly improve handling. I like the SBC because it is actually much cheaper to build that the V6 though I am keeping the V6 because I would love to put it back in once I am done with the V8. If anyone here as any suggestions at all on modifying this car to make it handle better and go faster please, I am open to anything. I am also on a tighter budget so junkyard diving is not at all out of the question. Also I am looking into a manual transmission to use with this car, does anyone have any suggestions?

Thank you for anyone who replies to this and to all the ones that replied to my original posts. I will keep you all updated with my progress.

[res0o7eb]

Also I have a Buick Skyhawk as a parts car (Then giving it to my buddy who is putting a 400 Cubic inch Pontiac in it and racing it so it wont go to waste)

Cool. We've discussed that Pontiac swap here: http://forums.h-body.org/viewtopic.php?t=195.
I've still got that in mind, but I have too many other projects, right now. Please post to this thread any detailed information and pictures of this swap. And/or get your buddy to join this forum and do it. Lot's of knowledgeable people here to answer questions.

You should also put a Pontiac engine in your Pontiac Sunbird.':lol:'

[Tailssideup]

I WANT to put a Pontiac in my car. But I got this engine for free and he wont sell his, which is the only one that I know of in the area. Ill see if I cant get him to join when he does it.