HAS ANYONE USED THE OFFY DUAL QUAD INTAKE? IS IT AS GOOD AS THE SP1. IM AM BUILDING MY FIRST BUICK,I HAVE BUILT CHEVY 350'S. I FOUND OUT THE BUICKS ARE TOTALLY DIFFERENT. I HAVE A 70 SKYLARK CUSTOM 350/350. I AM GOING TODAY TO LOOK AT A 455/400 IN A 73 LIMITED. I WANT TO BUILD A 12 SEC. STREETABLE CAR,WITH DUAL QUADS STICKING OUT THE HOOD. ANY ADVICE IS GREATFULLY APPRECIATED. I HAVE BEEN READING UP ON 455s. I KNOW THIS CAN BE DONE. I AM NEW TO THE SITE ,FIRST TIME ON . ANY COMOS WOULD HELP. AND CAN I DO THIS WITH THE 73 HEADS.
Offy 2x4 If you want 2x4 for looks ok, but don't look for any performance from it. Getting a BBB in the 12's is fairly easy to do on pump gas. There are lots of combinations out there doing this, none (that I have heard) of which are dual quads.
Get the book "Guide to Buick Performance Engines", and check out the websites of TA Performance, Jim Weise, and the other engine builders. Save your money on the dual quad, spend it on TA's heads instead. If you can't afford them, then get a set of earlier 455 heads for a little better compression. Really, all you need to get in the 12s is compression, cam, heads, and decent exhaust (ignoring chassis issues). The TA heads will probably make the biggest difference. They will allow you to run a milder cam, allowing decent street characteristics, but still give you enough flow at higher RPM.
Dual Quads. I recently put a dual quad set up on my 74 455 Skylark. Jim B AT PAE Enterprises reworked the dual quad intake for me. I run 2 - 600 edelbrocks on it with a mild cam. about 9.2 compression. The change from a stock intake and a 800 cfm QJET, redone by John Osborne. to the dual qual set up netted me 3 tenths on my first outting. 13.05 at 105mph There is more in this but I have not had time to go back to the track. The car is responsive even when driving around town. Granted I was going for the look but it might as well be functional as well. I have been pleased with the results so far, but I do not believe that I would have picked up anything without having it reworked. Joe
The problem with the Offy is that it does not have a commom plenum between the two carbs thus making tuning a real PITA. You would basically need to tune both carburators seperatly and I would assume that neither carb would be exactly the same. I would think that if you are looking for the most performance potential I would go with a single card setup on a quality manifold and with a properly sized carb. You will need to also remember that the BBB (Big Block Buick) likes lots of air so you will need a bigger carb than you would put on simalary built big block chevy.
SORRY IT TOOK SO LONG TO REPLY I JUST FIGURED OUT HOW. I AM NEW AT THE BUICK I JUST WANTED TO LEARN FROM SOMEONE WHO HAS WORKED WITH THEM. I CAN FIND CHEVY,FORD MOPAR GUYS ALL DAY LONG,BUT WHEN YOU SAY BUICK THEY LOOK AT YOU LIKE YOU ARE FROM ANOTHER PLANET. THATS WHY I WANT TO BUILD IT,THER IS NOT MANY BUIK GUYS WHERE I AM FROM AND I WANT TO SHOW THEM A LESSON.ENOUGH ABOUT ME BACK TO THE QUESTONS. I DID BUY THE BUICK BOOK AND I HAVED LEARNED ALOT,BUT I LIKE TO TALK TO SOMEONE WITH EXPERINCE. THIS IS WANT I WANT TO DO TELL ME WHAT YOU THINK. 1970 SKYLARK CUSTOM350/350,SWAPING OUT A 455/400 FROM A 73 LIMITED. HAVE A 72 OLDS REAREND WITH THE 8.5 GEAR, WANT TO RUN AOUT 3.42 OR 3.55 TO RETAIN HWY SPEED. GOING TO YOUS A LOCKER, DETROIT SAYS THERES IS QUITER KNOW. I WOULD JUST LIKE TO KNOW SOME COMBOS TO GET ME IN THE 11'S OR 12'S AND BE STREETABLE.I KNOW CHEVYS AND IT IS ALL HI RPM HORSEPOWER, SO EVERYTHING IS SET AT HI RPMS HI STALL TALL GEARS.BUT BUICKS ARE DIFFERENT. LIKE THE DUAL QUAD I CAN RUN IT ON A SBC WITH TO 500CFM CARBS AND HAVE GOOD HP. WETHER I RUN SINGAL OR DUAL I AM GOING TO CUT A HOLE IN A" FIBERGLASS HOOD " AND HAVE A BUG CATCHER STICKING OUT TO GET THAT RAM AIR,ALONG WITH THE LOOKS. MY BIGEST PROBLEM IS WHAT COMP RATIO,WHAT CAM, WHAT HEADS PLEASE HELP AN OLD CHEVY GUY.
Excuse me? No common plenum between the 2 carbs? Have you actually looked at one of theses? The front and back of the manifold are connected together and open. The problem with the dual quad intake is in the angle of the floor to the head, there is a pretty major mismatch here, it can however be corrected with some welding and reshaping of the port floor. I have done this on several manifolds and had good results. Out of the box with no mod, the manifold does not work well. Don't get me wrong here, the thing flows an incredidle amount of air, but the flow going into the head is disrupted with a "v" shape in the floor, this is not good. Jim Burek P.A.E. ENTERPRISES
Bigblock Go back and edit your profile at the bottom and add your name to your signature. Everybody's on a first name basis here like old friends. On your combination, Buick are easy to get into the 11's just got to buy the right stuff. First you'll want 10.0:1 FORGED pistons and a good set of moly rings. Get your rods resized and everything balanced. You'll need to zero deck your block after boring to make sure the pistons are flush with the top of the block and it'll give you true 10.0:1 and pump gas friendly. Buy the pistons with valve reliefs. If you can, find a set of "68-'69 430 heads or '70 455 heads. They have smaller chambers and flow better and again will get you closer to 10.0:1. You may have to do some light porting and get the stage 1 valves. TA SP1 intake manifold. Headers. MSD. Camshaft-look for something in the *234-*238 range at .050. Although pricey, you may need TA roller rockers. 3000 stall convertor. 3.73 posi. 28" Mickey Thompson ET streets. And last but not least, Buick breath hard and heavy. You'll need 850-950 cfm carb. Don't get a high vol/pressure oil pump. Get a oil pump rebuild kit, booster plate and pressure kit. Hi vol/press pumps wear out cam bearings in the first few minutes of start up. Also, TA sells a grooved cam bearing. Definately get those and follow directions. Oil is Buick's down fall. Pay close attention to that.
http://www.trishieldperf.com/ http://www.paeenterprises.com/ Read and learn:TU: Check out some other sites I've bookmarked regarding engines... http://www.buickpartsdirectory.com/engine.htm
BigBlock, First of all, please turn off your caps lock. It makes it seem like you're shouting, and I don't think that was your intent. It doesn't take much to get a 455 Buick in the 12s, after all - NHRA stockers and the factory stock muscle car racers run faster than that. Its all in the details, and selecting a package that works well together, and a package that works well on the street isn't necessarily a package that works well with dual quads and a giant hood scoop ( which aren't necessary to run 12s). A recomendation from a BB poster as to a "streetable" cam (reasonable idle and strong mid-range) may be completely different from what you may be looking for. Some of your statements are somewhat vague and contradictory, so its hard to tell what you want. Again, I would suggest you read the web-sites of some of the Buick suppliers and professional engine builders - TA Performance, Tri-Sheild Performance, PAE, Postons, and others - and read the Buick Performance book. The more informed and better planned you are, the better people will be able to assist you. If you are serious about a street "go" car (vs. street "show" car), and are on a fairly modest budget - I would build a fairly rugged short-block; 9.5:1 forged pistons, ARP rod-bolts, and do the oiling system modifications (but NOT a high pressure pump-just the booster plate). Top it off with a set of bowl-ported early heads, fairly mild cam (maybe 230deg @ 050?), and either a Edlebrock Performer or B4B dual plane manifold with a re-worked Q-Jet , a hood scoop isn't necessary. Either headers, or stock manifolds, dumping into 2.5 or 3 in exhausts. I've heard the X-pipes seems to work well. Use about a 2500 - 3000 stall converter in your TH350, with a shift kit. Your 3.55 rear should be about right, but you may need some heavier duty axles. This should get you in the 12s, with some fine-tuning maybe the low 12s, and run smooth enough to be a reliable daily driver. Mileage would be about average, about 12mpg? It would take a fairly stout ($) SBC to run with you.
Thanks for correcting me Jim. I thought that I had read that somewhere. And no I have not actually looked at one.o No:
