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How to Build a Street/Strip Goodwrench 350

How To Run 11s With Stock Iron Heads And A Simple Shot Of Nitrous

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We arrived at Fontana during Street Legal Drags day, along with a thousand other cars, just a few days before deadline. Our first baseline pass netted a slower normally aspirated run with a 13.13 at 103 mph, nearly three-tenths and 2 mph slower than our first test. We attributed this to warmer weather with less atmospheric pressure, because our 60-foot times were the same. After waiting in line for two hours, we rolled into the bleach box only to lose fire with a dead fuel pump. A quick diagnosis revealed a blown fuse in the Chevelle’s fuse box that we were using to power the nitrous arming switch. This also turned out to be the switched power source to the relay for our fuel pump. With a new fuse and the fuel flowing again, we decided not to be stupid and try the nitrous, because if the fuse blew during the run with the nitrous engaged, the fuel pump would quit and the fuel bowls would run dry and burn up the engine. Arrrgh. We couldn’t take the risk, so it was back to the shop for a complete electrical rehash of the nitrous and fuel-pump relay circuits.

At the expense of a completely blown deadline, we took the time to install the nitrous bottle heater. This demanded its own dedicated, 30-amp power circuit. This is when we realized that with the 20-amp bottle heater circuit added to the 40-amp draw from the electric fans, added to 12 from both nitrous solenoids, 10 from the fuel pump, 10 for headlights, and roughly 3 amps for the ignition, we were looking at a total load of 90 amps. And all we had to feed that drain was a 63-amp alternator. This required us to juggle amp loads in the staging lanes to avoid overloading our seriously underpowered alternator. It felt like that scene in the movie Apollo 13. Later, we researched a higher-output alternator and decided on a 140-amp CS130 Powermaster that will take the place of our weak-kneed 12Si alternator.

By now we’d performed multiple changes to the Chevelle, adding a vacuum-secondary, 750-cfm Holley, the 150hp nitrous system, and the MSD Digital ignition box. We decided to go right to the nitrous for the final passes, which now had to be run at Irwindale’s eighth-mile track. Arming the nitrous, we launched the car on the engine and then triggered the nitrous about 30 feet out. We did this to allow the engine to gain some rpm before we hit the squeeze, which would prevent loading the engine with nitrous at a too-low rpm. We set the MSD 6AL-2 to retard the timing back to 24 degrees with the nitrous engaged. As expected, the small-block felt exactly like a 500hp motor, responding with an eighth-mile 7.82 at 94.56 mph, which equates to roughly a 12.12 at 114-mph quarter-mile pass. The tires spun hard, which is why the 60-foot times were slower. Though hard to do, on the next pass we waited longer to hit the button, improving the 60-foot time to a still-slow 1.94, but this produced a 7.68/95.08-mph pass that’s equal to an 11.90 at around 115 mph, which is almost exactly 1 second and 20 mph faster than our best normally aspirated pass. That’s cookin’ for a brown bag 350 small-block Chevy with stock iron heads. As a point of history, we learned the following Monday that Irwindale closed its doors forever, so the Orange Peel was among the last cars down the dragstrip. A moment of silence is probably in order.

Along the way, we learned that the hydraulic side of a typical nitrous system is relatively easy to control. Where we had problems was on the electrical side, partly because of our Chevelle’s terribly outdated wiring harness and partly due to our own haste. It’s also worth noting that our Chevelle only weighs 3,460 pounds with fuel and driver and has a very good California Performance Transmissions 200-4R trans, a decent Global West suspension system, and a set of dated Mickey Thompson ET Street tires that all contributed to helping this car pull down a budget 11-second pass. With some tuning and better traction, this combination is conservatively worth 11.60s at probably 120 mph. Even though the new generation of LS engines are certainly more horsepower efficient, it’s clear that the small-block Chevy isn’t ready for the museum just yet.

PARTS LIST

DESCRIPTIONPNSOURCEPRICE
Goodwrench 350 crate engine10067353Scoggin-Dickey$1,499.99*
SD Vortec modified iron heads (pair)SD8060A2Scoggin-Dickey779.9
Sealed Power forged pistons, standardZL2256FSummit Racing287.6
Sealed Power ringsZE251KSummit Racing38.95
ARP rod bolts134-6005Summit Racing69.16
F-M rod bearings8-7100CH stdSummit Racing56.95
Hedman headers68,299Summit Racing169.95*
Edelbrock Performer RPM Vortec7,116Summit Racing189.95
Fel-Pro gasket setKS2600Summit Racing46.95
Fel-Pro Vortec intake gasket1,255Summit Racing33.99
MSD programmable CD box6,530Summit Racing359.95
NOS bottle heater14164NOSSummit Racing149.95
Spectre dip stick4,255Summit Racing6.95
Resize rodsN/AJGM125
Balance rotating assemblyN/AJGM200
Comp 10W-30 oil (5)1,594Summit Racing39.75
N2O Bottle fill 10 pounds N/ALocal50
Powermaster 140 amp CS 130 alternator47,860Summit Racing161.95*
Total $2,435.05
*Not included in total price.

Sources

Automotive Racing Products (ARP); Oxnard, CA; 800/826-3045; ARP-Bolts.com

California Performance Transmissions; Huntington Beach, CA; 800/278-2277; CPTTransmission.com

Edelbrock; Torrance, CA; 310/781-2222; Edelbrock.com

GoJo Industries; Akron, OH; 800/321-9647; Gojo.com

Federal-Mogul; Southfield, MI; 248/354-7700; Federal-Mogul.com

Hedman Hedders; Whittier, CA; 562/921-0404; Hedman.com

Holley Performance Products; Bowling Green, KY; 270/781-9741; Holley.com

Jim Grubbs Motorsports (JGM); Valencia, CA; 661/257-0101

McMillan Speed & Fab; Oxnard, CA; 805/732-8293; SpeedAndFab.com

MSD Performance; El Paso, TX; 915/855-7123; MSDIgnition.com

Powermaster Electrical Systems; Chicago, IL; 630/957-4019; PowermasterMotorsports.com

Scoggin-Dickey Parts Center; Lubbock, TX; 800/456-0211; SDParts.com

Summit Racing; Akron, OH; 800/ 230-3030; SummitRacing.com

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