What was the difference between the 88 and 89 L98 engines? The 89 had like 15 more HP, was it because of a bigger cam? Larger Intake? Better Exhaust? ect...

88 L98 230
89 L98 245 (I think)

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88 Formula 350 WS6
Upper and Lower SuperRam, 1000 CFM Accel Throttle Body, ZZ4 cam, 24# Motorsport Injectors, Larger Gutted Mass Sensor, Homemade Cold Air induction, PROM by performance resources, MSD 6a box, MSD Distributor, Accel SuperCoil, Taylor 8mm wires, TB Bypass, B&M shift Kit, 160* Thermostat, Flowmaster Muffler

Headers in the mail soon to be installed

 

ttt

 

Two cats on the 89. More power.

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"Restore decency in America. Ban rice!!"

 

not all 89's got the dual cat. I think the cam was different

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*89 Trans Am GTA
*Moderator at www.transamgta.com

To hell with the GM vs Ford war. We must unite, as brothers to fight the plague that is overtaking the world...RICE

Tony

 

According to the information that I have (summarized in <A REF="https://www.thirdgen.org/messgboard/Forum12/HTML/005622.html">this posting</A>) the '88 and '89 cams are the same.

 

Between 88 and 89 they did a lot of changes for example they switched to serpentine belts, started using VATS, and got rid of the cold start injector. I know this does not answer your question but they made a lot of modifications between those 2 years. I think they made a few minor tweaks to the engine and computer, which could have done it.

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1989 Iroc-Z 5.7 350, Blue, T-Tops

Lightly Moded:
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-- Blue LED Bakelite Dash & Climate Control
- I am just some 17 Year old spending every dollar I make on my car.

 

Actually, 88 was the first year of the serpentine belt system. The extra horse power and torque was the result of the G92 option if the car came equipped with it (only could be gotten with a 5.7 TPI motor (B2L) or 5.0 TPI motor (LB9) with 5 speed (MM5) manual). The G92 option included the N10 performance exhaust system (dual catalytic converters) which increased power output by 13%. The cam was the same for all 350s in 1988 and 1989.

[This message has been edited by CamaroRS (edited December 12, 2001).]

 

Dual cats

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89 TransAmGTA L98/Auto Grey/Grey T-Tops
Best 1/8th: 9.02 @ 76
89 TransAmGTA LB9/5speed FlameRed/GreyLeather Hard Top

 

I agree with those that say "dual cats" Both 88 and 89 engines are EXACTLY the same as far as power, belt systems, etc. Maybe slightly different ECM cals.

Both L98's put out 230HP@4800 RPM and 330HP@3200 FT/LBS ... HOWEVER, in 1989 the G92 "performance" option was available, boosting the L98 to 240HP@4400 RPM and 345@3200 FT/LBS (due to the dual cat G92 option).