SPAL FANS and 2 ROW DEWITT'S TECH Notes - Page 4 - ZR-1 Net Registry Forums

GOLDCYLON · 07-18-2013

May know soon as Dom and I have here close to a final tune.

Billy Mild · 06-02-2015

Quote:

Originally Posted by A26B

I have the Ron Davis in my ZR-1

The Ron Davis is a racing radiator that has 5 cores as compared to the stock 2 core. As a "racing radiator" it performs best at racing speeds where air velocity is high. Being thicker, actually makes it more resistant to air flow than the 2 core radiator.

A simple but effective modification that yields significant results, is to drill 3 or 4 holes in the thermostat flange, just inside of the seal contact area. This modification reduces back-pressure for coolant passing through the radiator & thermostat and therefore allows more flow coolant through the radiator, instead of the bypass. Bypassed coolant means hotter temps.

I strongly suggest you perform the t-stat modification before spending a lot of time & money on expensive radiators and fans.

As a side note, the only way to insure the stock radiator is as effective as it can be.... is to remove it and insure all the gravel & debris is removed and the vanes are reasonably straight.

What is this Thermostat mod that can be done?

Thanks,

Jeff

secondchance · 06-03-2015

Quote:

Originally Posted by Billy Mild

What is this Thermostat mod that can be done?

Thanks,

Jeff

I think the thermostat mod mentioned is drilling 1/8" hole/holes on the thermostat flange. I drilled three 1/8" holes at first. This worked fine during the summer months. However, once it got cold coolant temp wouldn't go above 150. So, I switched to another thermostat with just one 1/8" hole. This reduced interstate cruising coolant temp in summer from 208 to 213 (depending on 5th or 6th gear) down to 196 plus/minus and during the winter around 180 to 185.

07-18-2013	#31
GOLDCYLON Join Date: May 2007 Location: Peoria, AZ Posts: 9,155	Re: SPAL FANS and 2 ROW DEWITT'S TECH Notes May know soon as Dom and I have here close to a final tune. __________________ GOLDCYLON - 91 ZR-1 #2014 GOLDCYLON - 90 ZR-1 #2794, 4L60e (Formerly Schrade's) GOLDCYLON - 11 CTS-V Arizona State Director 91 WHITE/BLACK #2014. 380 P&P&PCed,Ported Heads, Jeal Long tubes, Corsa Exhaust/FIKSE FM-5s /LED TLs, LED Headlights, Front Wilwood 6 piston narrowlite calipers and rear Wilwood caliper street shop mod,CNCed Coolant Pipes,TPI Cvr,Filter cover,Stainless Bolts, DRM/DOM PROM /ZFDOC mod build #102,DRLs,BMAD with stainless Debris Screen,Coplan Air Blaster, Pioneer APP Radio 4,Brey-Krause HB,Sub Bar,Fire extinguisher seat mount,DRM Coilovers,LEDs everywhere,Compass mirror (orange),V1 DIC hidden display, Homelink sun visor, Carbon Fiber top x3 and APSIS Carbon Fiber interior, APSIS CF Steering Wheel/NAPA Leather, Banski trailing arms, Guldstrand front suspension,urethane bushings from Prothane (total suspension) ZFDoc drive shaft safety loop, raptor shift light (orange),AO engineering louver front plate, Console seat cushion, 96CE seats with black custom Sheepskins, ss billet catch can,Viper remote entry/alarm,Cragar Rear Louvers,LED side louver lights, Dewitts Radiator with SPAL fans and a Woods 160 T-Stat 90 RED/BLACK #2794. 4L60e Automatic Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless Headers, Corsa Exhaust, SAN Secondaries and Haibeck PROM, Exotic Muscle Coil overs, LED Interior Lights, LED Tail Lights, LED Headlights, 94 Sport seats with black custom Sheepskins , Cragar rear louvers, GS Front calipers, Banski Trailing arms, APSIS Carbon Fiber steering wheel, Front and Rear Baer Eradispeeds, DRLs, Guldstrand front suspension,urethane bushings from Prothane (total suspension), Dewitt's Raditor with Dual SPAL fans and a Haibeck 170 T-Stat 11 RED/GREY CTS-V