Thread: Kind Of A Drag

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I just took our heavy Chevy Monte Carlo to the track for the first time and averaged in the 15's (Boo Hiss) and that's even with using nos.

Ok how can I tune the car for optimum acceleration? What carb is best, Holley or Edelbrock (both are 600's) Do I pull the vacuum
advance hose? How rich a mixture for gas? What gear do I apply the nos? Should I use a cool can? What static timing is best? 8 or 12 BTDC? What tire pressures? (Street tires 205/70r/15, fronts 235/70r/15s back) How much air in air shocks? Do I loosen the front stabilizer bar? Do I use the lightest centrifugal springs in distributor?
Or is 15s all I can get out of a street Monte Carlo?

I see from your other post that it has some really lazy highway gears.... Might want to correct that situation before you get too concerned about the horsepower.... What engine, trans, rear gears do you have now? Not much too go on from your post.....

Hiya,
It's a 350 four bolt studded with flat top pistons and 71cc 2.02 World heads.
Ceramic headers with 3" stainless pipe with dynaflow knockoffs. Weiand dual plane with a re jetted 600 Edelbrock carter type. Re-curved distributor with a street-Fire ignition module. Nos hotshot adding 125-130 hp and a K & N filter.
Lunati 400 with flat hydraulic lifters and roller rockers. Hi volume oil pump with 8 qt Milodon pan and everything I could do has been beefed up.

Transmission THM 350 with B &M stage 1 shift kit and transmission cooler. Stock 2200 torque converter.

Rear is 8.5 10 bolt chevy with 2.76 stock gears with a lockrite posi.

I'da thought it would do better.

Ordered 3.76 gears for the ring and pinion replacement.
All I could think of.

The gears will help a bunch!!! Once you get it to move off the line, tuning becomes possible anyway.... Got some cam specs? what size tubes and collectors do the headers have? With flat tops and big heads, doubt you have a whole lot of compression.

There are a number of formula's on this links you will find helpful.I suggest you bookmark it.

http://www.wallaceracing.com/Calculators.htm

and

http://www.csgnetwork.com/automotiveconverters.html


Best dyno is the the ET slips in hand and understanding how to read them.

A 1976 Monte weighs 3900 pounds -plus driver and fuel you're probably in the neighborhood of 42-4300 pounds. Should probably look for low 14's when you get some lower gears. Higher stall (2800+/-) may shave a tenth or two as well..

Have Fun!

Originally Posted by 1gary

There are a number of formula's on this links you will find helpful.I suggest you bookmark it.

Wallace Racing - Automotive Calculators

and

Automotive Converters and Calculators


Best dyno is the the ET slips in hand and understanding how to read them.

Just want to add to this,it is somewhat a sensitive subject to me to say "well you can just add a 10th" by...............when in real life, short of power adders like spraying,it isn't that easy.More often than not the changes are in increments.All I am saying is consider a 10th huge.I suggest you don't do wholesale changes,rather do one change at a time so you can see the net gain or in fact the net loss.

In a round about way:

Torque is = to ET

HP is = to mph

That is especially true when considering a heavy car,torque that is.It takes a ton of torque to move a ton of car.

I can't believe this stupid page timed out on me twice! Testing, testing...

Hiyall,

Man, there's more calculators on those links to choke a mule! Thanks! They didn't have one that converts your pocket money into divorce papers by way of race parts.

My 6 ET slips show that my reaction time and launch were bad at first but my ETs were the best. As low as 15.2

As my RT and launch improved my ETs got slower. As bad as 16.8

Wheel hop at the burnout was devastating. Could have shattered the windows.

Nos in second gear lit up the tires and I slowed down on the strip to donate some tire rubber. So, Nos only in third gear.

Even feathering the throttle at launch couldn't keep the tires from smoking.

At the other end of the strip the car seemed to bog down even with Nos. Low RPM. MPH ranged from 91 to 96 MPH.

Static timing was moved from 8 BTDC to 12. Then settled on 10.

Used 92 octane pump gas. No detonation anytime even with Nos.

Seems like I got both a gear and tire problem.

I can't afford racing slicks at 200 a piece and since the economy slowed down the car has been promoted to dailey driver, grocery getter and work car as well. I'm dragging it on Wednesday and driving it to work the next day. So, I gotta compromise. It's our only car now. So, the gears can't be too low, the mileage too crappy but I would like to get in the low 14s and get that tower announcer to quit calling our car a "Hoopdee"

I suggest you go around the water box with street tires.When you get street tires hot they provide less traction not more.So no burnouts.Just a short hop to clean the tires off before you stage.

A gear change is going to help straying(ya-not a big fan of getting hook on the bottle)the engine in third.If you look at one of the formulas with your current gear ratio in third and the mph,you will see the rpm of the engine going threw the traps at the top end.The engine is saying I think it doesn't like straying at that low of a rpm.

If you go to any of the sites-Jegs,Summit,etc-you will find trailing arms for your rear end that are for traction.They do work and really are not that expensive.

Even for a street ET car.Keep a log of those times,what you changed and the effect it had.Fall into a routine you follow on every run.Develop that log that includes the time of the day and if you deep staged or shallowed staged by just bumping the stage light.Some tracks get tighter as the sun goes down and others get loose.

Years ago everyone used to pick on Peter Magel and his bullet nose Studebaker he drove to the track.Telling him he should build something faster.Peter watched guys spend tons and be breaking things some missing the rest of the season because they couldn't afford to fix what they blew up.Every wk Peter at the end of the day was at the win window to pick up his cash.Quietly under the radar making more money than anyone else.What I am telling you is from yrs ago from what I learned for him.Giant killers don't brag.They just go about their business getting the job done.

Thanks!

I didn't know about street tires OK no burnout then. cold tires. Good thing too. I got tire dust all over the rear quarters anyway.If I could get a grab that would help. Trailing arms too. I'll check the race shop on Monday when i'm off work.
Definitely changing the gears before I go out again. No sense wasting money.
Would the ET slips serve as a log? My wife's got em all in order. They should have date and time. She's also videoing some of my runs too.
Right now i'm just staging however I can just keeping the four lights lit. I'll try to space if just when the second lights come on.
Still trying for a launch routine. One racer told me to hold the brake and rev the engine to 1500 before launch. Is this a good idea? Then just kinda roll the throttle.
Once the Nos is applied there is a definite improvement in pickup. I'd probably be in the 18s if I didn't use it I guess.

I was thinking of anti pump up lifters too. I was thinking the engine capable of 6000 RPM. Or is that too much? I got a rev limiter on the spark module.
Like I said, I hafta drive it to work the next day.

I'll have the cam specs tomorrow.

Headers are Flowtech ceramics with 3" collectors reduced to 2.5 stainless pipes with 2 dynaflow type mufflers with a crossover pipe.

Carb is an Edelbrock 1406 with cruise and power set 1.5 stage richer from stock. Secondary jets changed from .065 to .068. springs are the "purple" ones that are the second stiffest I got opening at 8 degrees vacuum I think.
Vacuum idles at 16 degrees at 10 degrees BTDC. Best runs were with the timing at 8 degrees stock. Best launches were at 12 BTDC. Might be wheel slip messing with the ETs. AF ratio smells rich but no smoke. Still have water coming out the tailpipes.
However, this carb stumbles and stalls during raid lateral movement and sometimes during burnouts. Float level is perfect too, I checked.

Pistons are TRW with four valve reliefs per slug. Molybdenum barrel rings mated to what used to be a .600 crosshatch. Dang things never really broke in I still use oil but I don't see it and no leaks. Eventual fouling of the plugs I just clean and change em.

Plugs are Accell header plugs gaped at .040. Wires are Taylor 8mm.

Intake is a Weiand dual plane Hi rise with Quadrajet spread. I have a sandwich plate covering the extra hole area It was a closed plenum until I put in the sandwich plate and the Nos spacer. Now there's a gap. The carb don't like spacers. I got the exhaust crossover restricted but not blocked.

What about tearing up the vintage hood and putting on an air scoop ?
Or ram air piping?

I got a K&N filter with a plastic horn shaped air diverter in the middle. Noticeable 500 extra RPM with that thing installed. I was told I was getting enough air but its all hot air.

Well, every little bit helps I guess. They should have a drag racing school or something. With extra credit for lab time.
I sure appreciate the help!

Yikes , thats a big car. Drag tires, suspension tunning, losing weight and moving weight and learning the christmas tree ( and how to manipulate it), just to name a few. Theres no magic answer but these guys here will help you get her dailed in. Just dont go in head over heals, try and understand what and why different changes are helping and hurting so you spend money where its needed.

Yeah,true. We don't have a pile to spend. We're going for the gear ratio first. I can set that up myself. Then perhaps a torque converter. Wife says we can get drag slicks and change em at the track but.... pricey those are.

i can't find any trailing arms other than stock. no parts for this car sheesh!

You are talking about a gear change,but I don't recall you saying anything about a posti.

One other thing to consider.Daily driver heavy street cars are only as good as their weakest link once you start to go faster and start to hook the car hard.In general without corrections for those weakest links might get ya in trouble with the wifely and a standard "I told you so"!!.

From personal experience many years back, I'd like to suggest you find yourself a cheap daily driver to keep in reserve for getting to work.... Nothing worse then kickin' the rods (or other such malady) out of your daily driver when playing at the track, then having to look for other means to get to work on Monday...... Don't ask me how I learned this lesson!!!!