Pure Stock Drag Racing tips & tricks

[MotownMadman]

Marlin,
Years ago I had a BB 69 Nova I pounded the streets with, I had problems with a straight launch, after trying many different cures several things worked well and cured the problem. I fixed the wheel hop by adjusting the pinion angle which worked best between four to six degrees. I managed to get a straight launch by adding a extra leaf to the right side of the rear. That side always squats down farther then the left, I took the idea from a 69 Hemi Charger RT I had owned that came that way from the factory. If you want to retain stock appearence you can get a stonger set of leafs for the right side that look nearly the same as stock, it will make the car ride a bit different during normal operation but makes a world of difference with a good launch. I dont think this is needed running stock polyglass, but if you ever bolt on some weekend traction you could have an extra right spring set and U-bolts ready to go on. Now dont laugh, but a good old set of cable operated cut outs on the exhaust dont hurt either. [img]/ubbthreads/images/graemlins/grin.gif[/img] Another old street trick is to run your windshield washer hoses to the front of your rear inner fender wells and put bleach in the washer bucket. These ideas may not be for a original Deuce as yours, but if you ever build a ground pounder for the street they come in handy. Some might say it is cheating, but I have never seen a rule book for street racing. [img]/ubbthreads/images/graemlins/grin.gif[/img] [img]/ubbthreads/images/graemlins/naughty.gif[/img] The body mounts Pete mentioned is a big plus, also a cable tie down or solid motor mount on the drivers side also helps to put the torque to the rear wheels without losing a lot along the way with twisting and body motions first. The 292 angle plug Chevy heads mentioned work well while maintaining a stock appearance, not only are the plugs angled but they have no heat riser channel which makes for even exhaust flow. I have a set of these heads I may part with. Just buying the gaskets that block the heat riser to the intake will help. While it wont cure the exhaust flow being even, it will keep the air/fuel mixture a cooler temperature which does help. Removing the engine cooling fan and running an electric gives more power as your engine works less not turning the fan. For a street driven car you can set up a quick install electric fan for weekend fun, tie staps and a couple of electrical connections and youre in business. Coiling your fuel line through a coffee can packed with dry ice helps to keep your fuel cool, this makes a noticable difference and is something else that can be set up with a couple of quick connect fittings and some tie staps. Having these nifty tricks ready to install it only takes a few hours to prep a car for drag duty, then a couple of hours back to stock apperance. Just remember, no matter what, it's never fast enough and it can always go faster! [img]/ubbthreads/images/graemlins/burnout.gif[/img]
Motown [img]/ubbthreads/images/graemlins/beers.gif[/img]

[Rowdy Rat]

Marlin,

First time in this particular section of the forum... Interesting information posted here... Have to check in here more often!

I have a lot of data that you might be interested in. I have always been an early LT-1 nut although the ones that I've owned have always been installed in Corvettes, not Novas. Still, there are many similarities between the two so I think that I might have something useful for you.

First off, I agree with Pete... Your current camshaft is overkill and may actually be costing you some power. I've flow tested several sets of "186" castings and can tell you that even with a great three angle valve job, an unported "186" head starts to run out of flow around .450" lift on the intake port and .475" on the exhaust (compare this to the lift figures of .458" and .485"... the engineers knew what they were doing). There is absolutely no need to lift the valve any higher on an unported head... There just isn't any gain in flow to be had through the intake or exhaust ports.

Regarding the camshaft itself, the LT-1 cam has been discontinued for about a year now. Prior to that, Crane made these under license for GM, so what you were actually getting was a Crane camshaft in GM packaging. Regardless, they were absolutely identical to the original. I had two original LT-1 cams (the first removed from a 1970 Corvette at 1,600 miles, the other at 67,000 miles) as well as a new Crane manufactured GM cam checked on a Cam Doctor at Jere Stahl's shop in York, PA. With the exception of some wear related lift reduction on the 67,000 mile cam (as you would expect), there were no differences in the acceleration or lift curves. The exhaust lobe is identical to exhaust on the old "30-30" cam, but the intake is quite a bit different and accelerates off the base circle at a much faster rate (GM was able to do this because of the use of screw in rocker studs)... There is also quite a bit of overlap designed into the camshaft to make it work with the stock exhaust manifolds... There was a considerable amount of engineering work put into the LT-1 engine.

If you send me your new address Marlin, I will be happy to forward copies of the "186" flow data, the camshaft plots/data as well as some tuning/engineering data that was offered up on another forum by Duke Williams and John Hinckley.

Regards,

Stan Falenski

[Chevy454]

Great info, Stan! You really should stop by more often! If you wouldn't mind, I'd like to check out the LT-1 info you have...I'd gladly reimburse you for your time! And while you're at it, send Pete a copy to get him back into "small block mode". Then, maybe he'll get that silver Nova of his out and go find a certain Green W-31...(hi Casey!)

So, got any of that "hi-tech" info on any big block stuff? Like maybe some flow numbers? Or how about some cam doctor info on the 143 unit?

[JoeC]

One of the Corvette magazines this month did some flow teasting on original Chevy alu head vs modern aftermarket alu head. Big difference in flow numbers.

[Rowdy Rat]

Rob,

I'd be happy to send the information along to you and Pete as well... Just let me know where to send it!

I always got a real kick following the "pure stock" threads over on the Buick board... I didn't realize that similar threads existed here. I will definitely check in here from now on.

As far as "143" information, that's next. I currently have three big block cars that use that camshaft and I'm quite interested in getting some baseline data before proceding any further on the restoration process(es) for those cars. I have to track down a known, original "143" camshaft or two... When I do, I'll run them out to Jere Stahl's shop and have him do his thing. He actually has two different camshaft checking devices... The previously mentioned Cam Doctor as well as one of his own design that is much more precise (overkill for what I want done). In any case, when I eventually get the info back, I'll let you know.

Regards,

Stan Falenski

[Chevy454]

Stan:

I may have a couple of original "143" cams that came out of running (well!) engines...would you be interested in checking them out?

[YENKO DEUCE REGISTRY]

Stan,
I'll definitely take you up on your offer, and PM you my address. What you said is very interesting, and supports what the others have said.

So, is Crane still offering the blueprinted LT1 cam?

[Salvatore]

Hey Marlin, I bet the Crane cam in my Z/28 is probably the same one they offer for the LT1. What do you think? Standardized Crane spec job. [img]/ubbthreads/images/graemlins/dunno.gif[/img] Sam

[Zedder]

There's a lengthy and informative discussion on the 30/30 cam etc. on the NCRS board under "302 Chevy".

[Chevy454]

Hey, Marlin: Is THIS your card?! [img]/ubbthreads/images/graemlins/naughty.gif[/img]

Sam: that cam card above is for the Crane blueprinted LT-1 cam, and became GM's replacement (service) cam after the 3849346 cam was discontinued in December of '71 (info via NCRS). So, it was essentially GM who "standardized" the cams before Crane ever came along. But, don't worry, they have PLENTY of different blueprint grinds for everyone!