90’ Corvette (L98) Modifications (285 HorsePower)

New SW Headers
New Magnaflow Exhaust
New TPiS Air pump delete kit
New 180 deg thermostat
New Plug wires
New C4 Beam Plates
New Differential oil drain plug (drilled and tapped)
New Differential oil drain plug
New Billet Aluminum oil cap
Fluids Mobile 1 75W-90 Differential oil (limited slip)
Fluids Mobile 1 5W-30 synthetic Engine oil
Fluids Castrol TWS 10W-60 Transmission oil
Eliminated Air Induction system
Eliminated CATS
Eliminated EGR
Modified Oil Cooler Use NAPA 8020 and 9808 hoses cut to length
Modified Marc Haibeck Chips
....87 octane calibration.
....OE spark timing 23 + 6 = 29 degs. @ 4400 rpm. 24 + 6 = 30degs. @ 5000 rpm.
....Enabled manual transmission.
....Both fans to go on at 195 and both off at 190 degs.
....Added +5% at WOT fuel to support +20 hp.
....Disabled deceleration fuel cut off.
....Disabled EGR.
....Idle speed is OE at 600 rpm.
....91 octane calibration.
....OE spark timing 23 + 6 = 29 degs. @ 4400 rpm. 24 + 6 = 30degs. @ 5000 rpm.
....Enabled manual transmission.
....Both fans to go on at 195 and both off at 190 degs.
....Added +10% at WOT fuel to support +40 hp.
....Disabled deceleration fuel cut off.
....Disabled EGR.
....Idle speed is OE at 600 rpm.
....Knock retard reduced by 50%.


This is a 1990 (L98) with SW Headers, Magnaflow exhaust and ZF S6-40 Transmission. The modifications include eliminated air pump, eliminated EGR, Haibeck Chip and some other stuff (over 100 mph in the quarter). http://vexer.com/automotive-tools/1-...MPH-calculator

Had to modify the oil cooler a bit so it could be rotated. The oil cooler coolant hoses then cleared the SW headers with sufficient air gap.

 

 

Never heard of the "Disabled deceleration fuel cut off." Could you explain what this does (aside from the obvious) and the benefits?

 

(DFCO) Deceleration Fuel Cut Off is intended as catalytic converter protection during long decelerations from speed as well as fuel economy (Obvious). The ECM does this by shutting the injectors off which cuts off the supply of fuel to the engine with foot off throttle. I have NO CATS.

Disabling DFCO will help prevent engine stalling on deceleration and maintain the nice rumble like the BIG boys.

On vehicles with standard transmissions (ZF S6 40 for example) with modified engines DFCO can be rather harsh during shifting. In these cases disabling DFCO is Obvious as you suggest.

 

Nice car. Just a suggestion. You seem to be interested in obtaining the best possible performance from your setup. Why not tune for 91 octane, bump up the advance a couple or 3 degrees and gain some free horsepower? Willie

 

Good point.......I added a Marc Haibeck 91 Octane calibration chip

 

Is this possible with an 84? If so exactly how is it done?

 

Marc Haibeck is doing a 91 Octane chip for me as we speak for my 1990 (L98). I am not sure about an 1984 but Marc would know

http://www.zr1specialist.com/

Just like Willie suggests below. Marc bumps up the timing a few degrees on the chip but you then burn 91 Octane.

 

Nice work.