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Ok, so my 98 ta (non tcs car) with fast 78 and factory ported tb, I never had issues and have used for last 15+ years. Went to a FAST 90 since a did another cam swap (too cheap to pass up) and with the tb, there's slack in the cable on the top hole on linkage and on wot, cable sometimes jumps the linkage. Cable in the bottom hole of linkage, no slack, but gas pedal height changes. I'm at the point of trying a 1/2in spacer or drilling another hole in the middle of the current 2 holes on the linkage (which I'm assuming those 2 holes are for if your factory dbc tb was a 3in or 3.5in cam TB...? Besides needing to upgrade my pump and injectors cuz I'm too lean even under 5k, I'm almost to the point of rather putting my FAST 78 back on. Be nice to have that extra top end, but the pedal feel, cable crap going on is driving me nuts!
Also, why is the peg for the cruise control so tiny on the linkage to where the cable barely stays on the peg? I have 2 90mm tb's and both have same smaller peg. Is there a special clip that secures it on these aftermarket TB's? Besides that new $700-800 tb i seen from Holley having a larger peg on the linkage, I haven't seen any others. But I really don't even want to spend more than $300 on another tb either, let alone $700+.
Thanks in advance
Last edited by FU_I_AM_UltraZ; Dec 19, 2025 at 06:50 PM.
The factory cable on a 4th gen? Not to my knowledge unless you mount the bract on the fuel rail bolt to another location...? Maybe that's my issue? Hmm
I don't have tcs/asr. Which the thread states for the tcs style could be adjusted. Unfortunately, just a cable, peg end and sleeve for me. Worst case, i lose some top end and go back to my fast 78 and factory tb. Sucks but rather not have the added bs for a daily beater car just for extra 10whp up top. I'm just that frustrated with this issue. I'm sure I'm not the 1st person with a non tcs car to deal with this lol
That's what I'm thinking. But after looking at hawks, I think I figured out the issue. Gonna contact them to confirm, but.. seems like all aftermarket 90mm+ TB's are based off the 2000-02 LS1 cars with the 3.5in cam tb. Those years uses a 51.75in cable vs the 98-99 only uses a 51.00in cable. That .75in is why my pedal height decreases when i put it in the proper bottom hole of the aftermarket TB's. So i guess i do have to change out my 51in cable to the 51.75in cable. Also, the peg for cruise control is smaller from the factory on the 2000+ cars. So, that cable would have to be changed out or just remove. Idt I've ever used cruise control on my 98 and not just cus its t56 car, my 02 is also, but I've owned my 02 since new) and maybe used cruise a handful of times. I can't believe all this headache is cuz linkage being based off 2000+ LS1 cars. Why not changeable linkage depending on year of a customer's car? If this is truly my headache, that's really fk-up! Cuz long tubes are made for 98-00 cars with emissions or 01-02 with emissions or race version 98-02. Why not TB's? SMH
Its the length of the throttle cable being my car is a 98 and seems the linkage on aftermarket TB's are designed off of 00-02 cars. I wouldn't tear into an aftermarket tb and potentially cause more issues until its my last resort.
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FAST 90/92 intake throttle body cable issue 
