A COUPLE WEEKS AGO I POSTED A MESSAGE ABOUT A '75 VETTE THAT I JUST BOUGHT, BUT HAVEN'T BEEN BACK TO SEE IF ANYONE ELSE HAD ANY INPUT.  I REALLY DIG THE BODY STYLE, BUT I TOTALLY ADMIT ITS A DOG.  THE ENGINE IS SOUND HOWEVER (CONSISTENT COMPRESSION, GOOD OIL PRESSURE) SO I'D LIKE TO START WITH WHAT'S THERE.  ASSUMING MY AREA HAS LAX EMMISSION STANDARDS, WHAT DO YOU SUPPOSE I NEED TO DO TO RUN 13'S WITH MY STOCK, DISHED PISTON SHORT-BLOCK?  THE ONLY AFTERMARKET PARTS ARE  NO-CAT DUAL EXHAUST, A TORKER INTAKE (NOT TORKER II) AND AN EDELBROCK CARB (I ONLY ASSUME A 650-BY THE WAY HOW DO I I.D. IT?)  BEING THAT THIS IS A SINGLE PLANE INTAKE, I'M SURE THE ENGINE CURRENTLY DOESN'T BENEFIT FROM IT, BUT I AM ON A BUDGET, SO I'D LIKE TO RE-USE IT IF IT WORKS WITH THE RIGHT CAM, HEADS, EXHAUST, ETC. THE CAR ALSO HAS A REBUILD TH400 AND THE STOCK 3.08 POSI, WHICH I'D RATHER MESS WITH LATER, OR MUST I UPGRADE GEARS JUST TO GET IT TO RUN 13'S? THESE CARS ARE HEAVIER THAN THEY LOOK, I THINK.  ANYONE WITH INPUT? THANKS.  

big block  

AFR 64 cc aluminum heads (increaese compression and flow), comp XE284 xtreme energy cam (It'll build cylinder pressure) , headers, 3.73 gears, 2400 rpm stall converter. Tune it up fine.

This should get you into the 13's without taking out short block and also be driveable everyday.

I would agree...I'd think that would be a nice ride.  I can vouch for gears and converter making a HUGE difference as I switched from a stock converter and 3.08's to a 2400 rpm stall converter and 3.73's and it made a world of difference.  

For the cost of aluminum heads you could probably switch to a set of vortec cast iron heads and have enough left over to purchase a new intake to match them...but I'm not sure which will be better...its just an idea...someone else can debate that.

YEAH I KIND OF FIGURED THAT'D BE ABOUT WHAT IT'D TAKE.  AS FOR VORTEC HEADS AND HAVING TO BUY A NEW INTAKE, THAT WAS ACTUALLY WHY I ALWAYS THOUGHT BUYING ALUMINUM HEADS WAS A BETTER BET.  DO YOU GUYS THINK MY TORKER INTAKE IS WORTH KEEPING?  AND WHAT KIND NUMBERS DOES THAT CAM HAVE?  IF THEY'RE SIMILAR TO WHATS BEEN OUT THERE FOR YEARS, I COULD OPT FOR A DIFFERENT BRAND THATS AS REPUTABLE BUT MAYBE CHEAPER?  

Comps xtreme XE 284, dur 240/ 246 at .050. lift 507/510, 110 degree lobe sep.

Your Torker will work great this cam. These Xtreme cams have very agressive opening ramps on their lobes. Good springs and retainers and push rods are a must. Any good aluminum heads will come with these though.

Your vacuum will be low. It may be a problem for your brakes and headlight openers.

If this is so you can go down one to two steps smaller cams then use 1.6 rockers to bring the lift up. Go with the XE 268 224/230 @.050, 477/ 480. With 1.6 rockers it will have 508/512. This should produce 16-17 hg of vacuum to operate everything and give you tons of torque.

Edited 8/31/2006 9:18 pm by rebldryvr

THANKS.  I FIGURED I'D GO WITH THE MILDER CAM YOU SUGGESTED.  INSTEAD OF SWITCHING REAR GEARS, DO YOU THINK SWITCHING TO A 700R4 TRANNY WITH THE LOWER FIRST GEAR WOULD WORK?  I'M NOT SURE HOW THE GEARING VARIED DEPENDING ON APPLICATION WITH THESE TRANNYS, BUT I'VE READ THAT FIRST GEAR IS TYPICALLY LOWER THAN SAY, A TH350 OR 400.  ITS OUT OF A 1/2 TON '84 CHEVY VAN. I KNOW ITS ONE OF THE LESS DESIRABLE YEARS, BUT IT IS ACTUALLY A GM GOODWRENCH REBUILT, IF THAT MEANS ANYTHING AS FAR AS UPGRADING ITS DOWN POINTS.  WHATDYA THINK?  

First gear is like 3.06 in 700r4, Th350 is 2.76, so you will get out the hole faster. The rest of gears are 1.82, 1.0, and I think .70 overdrive. If you get this tranny, you will still need at least 2200 stall to work with the cam. I believe their are companies that make lock up converters with stall now.

I have a New Process 440 manual trans in my 65 which has the same gear ratio as the 700r4. I have 3.36 rear gears. It comes out off the line like a monster, lots of tire spin, but the wide ratio between first and second drops the rpm down a little below what I want for maximum performance. In the end, steeper gears would still be better for both of us. Obviously, the it cruises at freeway speeds, 1900 at 70 mph. 3100 at 100 mph.

If you keep your Th350 and go with 3.73 gears and use 28 in tires, freeway cruising at 70 will be around 3000 to 3200 rpm which is very livable.

There are other issues when changing the trannys such as moving the crossmember back for the 700r4 and shortening the driveshaft (700r4's are 3 inches longer). It could be the thing to leave to last to change.

ACTUALLY I ALREADY HAVE THE 700R TRANNY--I GOT IT FOR FREE OUT OF A VAN THAT HAD LOTS OF PROBLEMS BUT A FRESH TRANNY.  IT WAS ACTUALLY OUT OF AN '85, NOT AN '84 AS I FIRST STATED.  I'M ALSO PRETTY SURE ITS A 400 TRANNY THATS CURRENTLY IN THE VETTE.  I DIDN'T REALLY I.D. IT WHEN I WAS UNDERNEATH, SINCE I DON'T HAVE A PAVED DRIVEWAY AND I LIKE TO LAY IN THE DIRT AS LITTLE AS POSSIBLE, BUT I'M PRETTY SURE THATS WHAT CAME IN THESE THINGS FOR THE MOST PART, ASIDE FROM A STICK.  EITHER WAY, ITS CURRENTLY A TOTAL PIG OFF THE LINE, AND I THINK MUCH OF THAT NON EXISTANT LOW RPM TORQUE IS DUE TO THERE BEING A SINGLE PLANE INTAKE ON AN OTHERWISE STOCK ENGINE (NOT THAT A TORKER INTAKE IS LIKE A SUPER HIGH RPM SCREAMER PIECE OR ANYTHING).  BY THE WAY, WHAT KIND OF VEHICLE IS YOUR SET-UP IN?  AND DO YOU HAVE ANY IDEA WHAT THIS TYPE OF VETTE USUALLY WEIGHS?  FIBERGLASS OR NOT, I THINK ITS HEAVIER THAN ONE MIGHT THINK, BUT MAYBE I THINK THAT 'CAUSE ITS SUCH A SLUG.  I STILL REALLY DIG IT, POOCH OR NOT.  

My car is a 65 Impala SS. It weighs about 4100 with me and my crap (Tools etc) in the trunk. Your vette weighs about the same. They are very heavy. Heavy duty frames.

Your car could slow off the line do to tuning not being optimum. That's easy to change. My buddy who has a frame resto 65 Impala SS with a 396 couldn't get it to do a burnout. Pathetic. It turns out it was tuning. He was reading a 1965 repair manual talking about points and such when he was running a HEI. He gapped the plugs wrong, timing was off, alot of stuff. It was a dog. All I did was retune it without buying any new parts and now it hauls butt.

If your car is has the stock smog low compression 350 you can pick up quite a bit of power by giving more lead timing. The intitial timing should be around 12-14 degrees. You can get a spring and weight kit for the HEI distibutor that will allow the centrifigal advance to open faster. Do these two things to start to see if this helps.

 I THINK I'M ALSO GONNA NEED TO GET SOME INFO ON TUNING EDELBROCK CARBS, SINCE I'VE GOT A LIGHT PING AT HIGH RPM. NOT AT CRUISING SPEED, JUST WHEN THE SECONDARIES ARE OPEN.  I KNOW ITS NOT BECAUSE OF LOW OCTANE GAS, BECAUSE THIS IS A 8.5 TO 1 COMP. MOTOR. ITS ALSO THE "J" CODE MOTOR, WHICH I'VE READ IS THE 165 HP MUTT.  DO YOU THINK I JUST HAVE TO EXPERIMENT WITH SPRINGS AND WEIGHTS TO GET THE ADVANCE RIGHT? OR DO I NEED TO GET THE CARB RIGHT FIRST?  I THINK I PROBABLY JUST NEED TO RICHEN THE SECONDARY SIDE, BUT SINCE I DON'T KNOW WHAT I'M DOING I'VE JUST BEEN GOING EASY ON THE THROTTLE UNTIL I DO.  AND I LOOKED UP SOME SPECS AND FOUND THAT THE CURB WEIGHT IS A TICK OVER 3500 LBS. WITHOUT DRIVER OF COURSE.  

13.9s aren't all that tough to get, even draggin' some weight.  I'll assume you're runnign street tires at the strip, which means steeper gears aren't going to do much but make you spin worse.

Against a stock-stall converter the XE274 or 282 are going to be pigs.  A converter change is in order if you're going to go that big.

First order of business, as you have correctly identified, is better heads.  Better heads make a world of difference.  Obviously, you need smaller chamber 64cc heads if you're going to build any compression, but even with them your compression is barely going to crack into the 9s.  Use a thin head gasket like the GMPP .028" compressed thickness composite head gasket ($33/set from Scoggin #### and other places and they work- I've used them several times).  Thinner steel shim gaskets would raise compression further but they ain't easy to seal up against an old block that may not be perfectly flat on the deck.

Choice of heads for a small block is about limitless but AFRs would be the top-shelf choice, out of the box (180cc intake, 64cc chambers, 2.02/1.60 valves).  A set of Trick Flow 23* heads would also work well, etc, etc.  Something in that general range of specs and whatever fits your wallet.  Aluminum is more money but probably worth it for the weight savings.

Cam..... your stock cam is a pathetic pig.  Anything you shove in there would be "big" comprard to a stock 1975 cam.  With the modest compression and stock stall converter figure 220* duration @ .050 is about the upper limit of what you can run.  There are many choices for a small block but I'll give you one.... The Comp XE262.  Sounds tiny compared to what others have suggested but it's GIGANTIC compared to your stock cam.  At 218/224* duration it's almost 20* bigger than stock.  And the 110* LSA is a bunch tighter than stock with will help build much-needed cylinder pressure.  Much bigger and you're likely to go slower.  This is one of those areas where smaller is better.  You've heard stories about people who over-cam their motor, right?  Don't be one of them.

Intake.... if you can find a swap-meet or ebay Performer RPM I'd use it.  A single plane is a bit much for this combo.  You're building for TORQUE here, not so much for peak HP, and the RPM has proven itself over and over again in applications like this.  With he mild gearing and stock converter you need torque to get it out of the hole.

Exhaust... if you can possibly spring for a set of shorty headers along with those duals it would be well worth it.  Factory manifolds are like giving away horsepower and torque for no reason.  The cam I have suggested will work with factory manifolds but any performance cam will definitely give better results with some tube headers, even shorties.

Converter.... if you need to pull the motor out for any reason you might as well upgrade the torque converter since you can remove/reinstall almost effortlessly at that point.  Even stock motors will act a lot stronger than they are with a mild ~2500 stall in them.  Lauching is both easier to modulate and stronger.  The cam I have suggested with worth with a stock converter but it'll be happier with about 2500 stall behind it.  Go with a bigger cam than that and a higher stall converter should be considered mandatory.  FYI- your trans ias probably a TH-350 automatic.  If so, the pan with look like a square with one corver cut off at 45*.

For comparison, I had a mild carb'ed 350 in my wife's 92 Camaro (full weight including A/C) that was ABOUT AS STRONG AS WHAT I OUTLINED ABOVE that ran 13.6 @ 104.5 with a stock stall converter, and a stock 2.73 peg-leg open diff on street tires, running a 2.2 60-foot time.  Switching to 4.10s, posi and DRs netted 13.3s at the same MPH, still using the stock stall converter.  With a 2500-3000 stall I might have been able to crack a 12.99999999, but I sold the car before that.

Look at the new packages from edelbrock.sell off your stock 350.that year vette won't suffer any from not having the original smog 350.take your cash and get yourself a 400 small block,add the edelbrock kit,roller cam preferably and the torque you'll be making will band-aid the crappy 3.08 gears untill you can step up the rear set up.just make sure you include the matching torque converter for the cam.don't factor in the 3.08 gears when you pick a converter if your sure you will change them at some point.so most likely a 2000-2700 stall speed would be great.besides with the torque of a hot 400 you may not want to bother with gears.you should get decent off line pull and a sweet top end.good luck.p.s i would still change the gears to at least 3:55's.look for a wrecked vette with a better differential.there are so many abandoned projects in the papers.search the bargainnews.com.  

After reading all of the advise, it looks like most people have given you good advise. Your vette is pretty heavy and should be around 3800 lbs full of fuel. I agree that you need to let that motor breath a little better with a better intake , heads and headers. The mid 70's choked engines down considerably in the name of fuel economy and smog emmissions.

A higher stall converter is definetly important to get the revs up at launch. As for rear gears, stepping up to 3.55 or more will help more in accelleration than anything else. Be careful choosing rear gears. Most people recommend big gears like 4.11 because they think bigger is better. Gear selection should be a combination of RPM, Trans gear ratio, rear gear ratio, tire size,  torgue and power. Consider all of these before you make a decision.

Too much gear with too much torque will hurt you with tire spin. Put on some slicks and you may bog the engine with the same power. Decide what you want the car for the most. If you are building a race car you will want a close gear ratio trans, high stall converter, high rpm intake setup and a tall rear gear. If you are focusing on a daily driver, the previous combination may not be the best set up. Too many people build race cars for the street and cannot drive them and they are not happy.

THANKS YOU GUYS FOR THE ADVICE.  WHILE I WOULD LIKE TO PUT A BIGGER MOTOR IN, LIKE A 400, I KIND OF NEED TO WORK WITH WHAT I HAVE FOR THE MOST PART, AT LEAST THE SHORT BLOCK.  OTHER CAR PAYMENTS (THE VETTE IS PAYED FOR AT LEAST) HOUSE PAYMENTS, HEALTH INSURANCE, CHILD SUPPORT AND TUITION SAVINGS FOR SAID KID'S FUTURE USE ARE REALITIES WE ALL CAN RELATE TO.  OF COURSE HEADERS ARE A MUST. AND AT LEAST A CAM UPGRADE, WITHOUT GOING TOO OVERLY ZEALOUS ARE PLANS AS WELL.  TO FIT HEADERS I'M SURE I'LL HAVE TO UNBOLT THE MOTOR AND AT LEAST JACK IT UP, SO I MAY AS WELL GO THE EXTRA STEP AND TOSS A CONVERTER IN TOO.  I WOULD LIKE SOME GOOD HEADS, BUT I'LL HAVE TO SEE WHAT'S AVAILABLE USED (ANYONE IN WISCONSIN HAVE SOME? I DRIVE TRUCK ALL OVER THE STATE IF SO).  AS FOR THE INTAKE, IS THE "TORKER" A TORKER IN NAME ONLY? I THOUGHT IT WAS A DESIGN FOR MID RANGE POWER.  IF ITS OK FOR MIDRANGE I'LL KEEP IT, AS IT SEEMS LIKE THE CAMS THAT I LIKE ARE ALL KIND OF MIDRANGE ANYWAY, AND A CONVERTER WILL MAKE THAT WORK, RIGHT?  AND ABOUT GEARS, I SEE GEARS LISTED FOR 12 BOLTS ETC, ARE THESE WHATS GOING TO WORK, OR IS THIS A DIFFERENT CARRIER ALL TOGETHER, WITH THE IRS?  THE POSI SEEMS TO WORK OK, SO THATS WHY I'M RELUCTANT TO MESS WITH IT RIGHT NOW.