This is for my '68 Camaro street car which is currently running 14.3 at 5,500ft. above sea level. It's primarily a street car that can be driven anywere but recently been takin it to the dragstip and looking to improve my times a little. Don't have the money to do much modding (daughter going to college next year) but looking for a few tips that may help.

Car: ZZ383, TKO600, 12 bolt w/3.73s, 670 Avenger Vac 2ndry (jets lowered 2 sizes for high altitude, BFG TA 255-15s, MSD Ign, 30 deg. total, timing.

Here's a few ideas questons I'd appreciate feedback on:

1. Car curretnly burns the rubber if much RPM at take-off. Rear tires are at 30psi - What can I safely lower psi to for better take-off.
2. I've got a set of old-school Lakewood tractin bars that were on the car when I bought it - would it be worth it to put 'em back on (car has 5-leaf).
3. How much would I expect to gain from a 750 Double Pumper vs. the 670 Avenger?
4. Spec sheet on this engine says max RPM is 6,000. Max HP is 437 @ 5,500rpm and Max ft-lbs. is 460 @ 5,500rpm. All that said, what RPM should I be shifting at??

I'm not trying to make it a drag race car but for the most part just want to be more competitive with what I got. Any tips on take-off also appreciated.

Thanks!!

Small nitrous kit (100HP) and a set of drag radial tires should make a big difference.
That way you would have the extra power and traction that you need when at the track without taking away from the "driver" status of the car.

The problem isn't you needing more power, it's getting it to the ground and using what you have. With 430hp atc give 15 or so off for accessories and what not, there is no reason you shouldn't be in the mid to low 13's.

The 5-leafs are killing you and the traction bars would make the ride pretty stiff on top of it. You could sell the 5-leafs and fund a 3-leaf set up with slide-a-links or do the caltracs with their newer split mono springs.

What rpm are you launching at and how does the 60 foot look? It really helps to practice your launches and play around with what works best before competing.

Without putting the car on a dyno no one really knows where you should shift at, most shift at where the torque and hp lines intersect, other than that, use the seat of the pants feel, run it until you feel it nose down and stop pulling, right before that, you should shift.

Lose weight! And including the driver too.

A F/G hood and front bumper for starters, an aluminum rad too. An aluminum water pump, intake, heads, headers, etc., etc... No A/C or P/B's

Manual steering and drum brakes. Light weight rims and smaller, lighter front tires.

Then consider moving the bat. to the back.

pdq67

PS., and mono's w/ slappers can be ran deep into the 10's for more weight savings in the rear.

Sheeze John, I'd shift right after the horepower peak.

I lowered bfg radial t/as to 13 psi and they hooked alot better than higher air pressure, launch at 1500rpm w/ a muncie 4 speed and switched from a vac. sec. 780cfm Holley to 825 cfm mighty demon and took off 1/2 second.

Dan E.
69 SS396 4spd. 4.10posi. x66 coupe

Lose weight! And including the driver too.

A F/G hood and front bumper for starters, an aluminum rad too. An aluminum water pump, intake, heads, headers, etc., etc... No A/C or P/B's

Manual steering and drum brakes. Light weight rims and smaller, lighter front tires.

Then consider moving the bat. to the back.

pdq67

PS., and mono's w/ slappers can be ran deep into the 10's for more weight savings in the rear.

I am with paul..put her on a diet.

This is for my '68 Camaro street car which is currently running 14.3 at 5,500ft. above sea level. It's primarily a street car that can be driven anywere but recently been takin it to the dragstip and looking to improve my times a little. Don't have the money to do much modding (daughter going to college next year) but looking for a few tips that may help.

Car: ZZ383, TKO600, 12 bolt w/3.73s, 670 Avenger Vac 2ndry (jets lowered 2 sizes for high altitude, BFG TA 255-15s, MSD Ign, 30 deg. total, timing.

Here's a few ideas questons I'd appreciate feedback on:

1. Car curretnly burns the rubber if much RPM at take-off. Rear tires are at 30psi - What can I safely lower psi to for better take-off.
2. I've got a set of old-school Lakewood tractin bars that were on the car when I bought it - would it be worth it to put 'em back on (car has 5-leaf).
3. How much would I expect to gain from a 750 Double Pumper vs. the 670 Avenger?
4. Spec sheet on this engine says max RPM is 6,000. Max HP is 437 @ 5,500rpm and Max ft-lbs. is 460 @ 5,500rpm. All that said, what RPM should I be shifting at??

I'm not trying to make it a drag race car but for the most part just want to be more competitive with what I got. Any tips on take-off also appreciated.

Thanks!!
LOL maybe some of you guys missed this.
Just took out a loan for my schooling, I can empathize.

1.....get some drag radials to replace the BFG TA's
2.....Dump the 670SA and get a 750DP or 770SA
3.....Play with the timing..probably wants a few deg's more total
4.....get the car dyno tuned or buy a wideband and tune it for ideal A/F ratio.
5.....Practice getting 60 foots dialed in and shifting at WOT

Start keeping a log book and make small changes and keep record of what works and what does not...

1. Car curretnly burns the rubber if much RPM at take-off. Rear tires are at 30psi - What can I safely lower psi to for better take-off. If they are standard radial tires they will cup if you lower the pressure too much I would suggest you lower the pressure 2psi at a time and make a pass. Repeat untill you stop making progress

2. I've got a set of old-school Lakewood tractin bars that were on the car when I bought it - would it be worth it to put 'em back on (car has 5-leaf). Yes put them on

3. How much would I expect to gain from a 750 Double Pumper vs. the 670 Avenger? I believe you would gain a great deal going up in CFM With that engine I would even consider an 850 double pumper. However there may be more in tuning your 670 also

4. Spec sheet on this engine says max RPM is 6,000. Max HP is 437 @ 5,500rpm and Max ft-lbs. is 460 @ 5,500rpm. All that said, what RPM should I be shifting at?? start at 5000 and go up 200 rpm from there untill you lose progress

Most importantly enjoy the process.
Milan

I'd also say yes to putting the traction bars back on.

Recurve your distributor to get in full advace as soon as possible.

Tires are a big issue but quite mesh with your low budget approach. You need some Drag Radials of some sort. Problem is, they are not going to last long on the street. Trying to race with regular radial tires is like pushing a rope...you just aren't going to get anywhere.

There is a ton of e.t. to be gained in the 60' without much $$.

I had traction problems too.
I had lakewoods on my single leafs.
But the snubber wasn't in the spring eye and it was preloaded HARD against the spring. There was no give and it just broke loose immediately.

I switch the CE traction bars that have the J-bolts. They hit the snubber right into the spring eye.
I had to use wedges to get the snubber off the spring to allow for some spring wrap up.
Then I switched to an ET Street DOT slick.

I went from a 2.69 60' to a 1.62 with that change right there.

Are you getting wheel hop when it breaks them loose?

If you get new tires get a 275/60 drag radial.Run them at 20psi. If you have the means go with the 750dp carb.run 36* timing with 92 -93 gas.Put the bars on and adjust or shim so snubber has 1/4 to contact spring .if the bars are short of the spring eye dont worry about it at this performance level but they should still be the decent J-bolt type if you want them to work.start your launch at 1500-2000 and learn from there .If it bogs step it up 500 at atime.Shift at 5500. Get ready to spend alot of money if you like racing the car cause believe me , youll get used to it then want to go faster.

Bill, where in NM are you? Just curious.

What is your MPH in the 1/4?

At 5500ft a bigger carb will not help unless your mph is 110+, your 670 is plenty. You do need to tune your secondary opening rate though, they might not be opening all the way.

And like everyone said above, get some drag radials for the track.

Bill, where in NM are you? Just curious.

What is your MPH in the 1/4?

At 5500ft a bigger carb will not help unless your mph is 110+, your 670 is plenty. You do need to tune your secondary opening rate though, they might not be opening all the way.

And like everyone said above, get some drag radials for the track.

I work in Alb. but live in the East Mountains outside of town. My speed is right at 100mph. I'm also skeptical of the secondaries.

Just move on to a cheap pair of real slicks! Say an 8.00 or 8.50 here!

And right, the key to slappers is to make sure they hit right under the middle of the front spring eyes! Mine have 1/2" bolts and such so I can adjust them regardless of anything else! Noisy slapping, BUT DO THEY SLAP!!

Along w/ coil-over shock overload springs that I adjust for pre-load side to side.

pdq67

Wow - I really appreciate all the feedback and am encouraged that my times will benefit. Now I have some response and some more questions:

1. I've been shifting at or just under 6,000RPM which based on above comments tells me I'm pushing past the sweet spot to shift and wasting time. Hmmm....maybe a 1/10th or two to be gained right there!
2. Sounds like I really need some drag radials and could see at least several 1/10ths reduction with the added traction and RPM at launch.
3. I'll try upping the timing a couple degrees (according to GMPP fastburn heads are supposed to take less but not sure that's reality or not)
4. I'm going to order a wideband 02 sensor/gauge pkg - saw one on sale at Jegs for $215 My carb could be underjetted cause on one of my recent runs felt like the gas was cutting out at the last stretch of the 1/4 mile run.
5. For now will try and lower psi down to 25 or so - seemed like my car got better traction the first time I went to drags and had spare tire and 70lbs. of tools in the back. This last time I took it all out and really hurt the traction.
6. Will look at my advance curve again and try and pull it in quicker if possible.
7. To answer questions on wheel hop - not getting wheel hop - once car hooks it stays put and is steady w/o hop.

Here's a few more questions:

1. We can only get 91 octane premium out here (suppose due to high altitude) Would putting in some 104 octane help?
2. I have adjustable QA1 shocks in front and rear. Would setting rear shocks softer help or hurt traction on take-off.
3. Thinking about cutting the choke tower off of my 670 Avenger dont really like elec. chokes and thinking about just eliminating the entire contraption. Maybe better air flow?

Thanks again to all!!!

Real slicks, not drag radials, you will see the difference in them.

And you don't need any more octane than what your engine will tell you it need's.

pdq67

Bill, you never said what class you're trying to run because everything you do could change your class. One of the cheapest things that you can do is to pull your distributor and take it to someone who has a distributor machine. Let them set it up so that your total advance is all in at 23 or 2400 RPM. Then time your engine to a total advance of around 38°. Do not hook up your vacuum advance, plug the vacuum line off at the carb. Just before you make a run put in a new set of plugs. Just after the finish line chop the ignition and when you get on the return road pull couple of plugs and see what they say. The 104+ will help your octane somewhat but it will also add a reddish brown tinge to your plugs. I would suggest you just use the pump gas until you get a good plug color.

As far as the choke goes, I disconnected and wired mine wide open 40 years ago. Just start to turn it over pump a couple of times and it's running.
Back in the day I started with a full tank of gas, the spare tire where it belonged and about 50 pounds of tools set to the very back of the trunk. Remember traction is your friend. The added traction that you will get from this will overcome the extra weight that your carrying.
I'm assuming you have headers if not wire the heat riser wide-open.
Put a Mr. Gasket half-inch number[ 98a ]carburetor spacer under the carb to keep the gas cooler. Install a cool can in the line. The cooler the gas the denser it is.
These are just a few of the low-budget things that you can do and I hope this helps you.
Jim

Another vote for drag radials.

Based on ending last year with best of 13.2. First 2 runs this year ran 13.3 with BFG's radial's.

Put on MT Drag Radials.... 12.85.... Yeah they work.

Have fun...
Brian

O.k. - drag radials it - is 1 for Christmas and 1 for Birthday.

Jim - thanks for the feedback and to answer your question I'm not really in a class and not really looking to be in one. My track has what they call Street/Grudge racing on Friday nights and that's all I run in. One race I may be whooping up on a Honda and the next getting left in the dust by a 9 or 10 second car. Our local track staff doesn't put much effort into trying to pair cars up well during the "grudge racing" events so it can get interesting.

You aren't listening to me! Real old-fashioned slicks!

pdq67

You aren't listening to me! Real old-fashioned slicks!

pdq67

I'm with ya pdq and sure your right about true slicks having the advantage over the drag radials and will consider that route. I'm just thinkin there may be an advantage (since I don't race too often) to driving my car to work on the drag radials and then go right to the track and home w/o changing wheels.