1/4 mile gearing for turbo

horndog

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Gday guys, Im running a GT2860 on a Gen1 Busa with 9"over arm and Hays clutch. So far Im only tunning 9psi but intend to go to 15psi.

I currently run 18/45 gearing and am getting 1.55 60'. I am getting mixed feedback on whether or not to change the gearing. Some say the turbos like the load and I should stick with current gearing and cross the line in 5th gear. Others say to run something like 17/48 and run it out to 6th gear.

My best ET so far is only a 9.42 @ 144mph as I am still working out the Hays clutch and am a heavy boy.

Could I get some feedback on gearing from guys who have experience with this on the 1/4 please? Not interested in street performance or what you heard or read. Cold hard facts only thanks.
 
How much do you weigh?
I've had friends running stock gearing that have had success, but have heard 16/40 works well too. If your a heavier guy (over 220 or so) the extra gear may help.
Its all a ratio.
16/40 is 2.5
18/45 is 2.5
17/40 is 2.35
For a 1.55 60' I think the et and mph are low. I'd try stock gearing and see how that works, but that's gonna be a little tougher on your clutch. Hopefully you have heavy springs. It could be possible your clutch is slipping a little which could explain the mph being low.
Its just my .02 but it's likely you'll get 6 people saying I'm wrong. (Oh well) Experiment and see what works for you.
 
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Thanks Blake I weigh 275 in gear. The clutch was definitely slipping up top. I am adding some extra weight to the arms to try and stop it. I have been reading that guys are running 1.3 60' with the Hays clutch but maybe with my weight thats a pipe dream.

Perhaps I should try 17/45 and see how I go. That will give me 2.64.
 
Everybody rides a little different what works for me may not work for you. Try going up and if that doesnt work go down. We can talk all day about what worked for other people but at best thats just a baseline.
 
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Gear it like you would a motor bike. It will ride so much better. All that nonsense about turbo needing load is the stupidest stuff ever
 
I can honestly say the the Turbo does need some load to help with the spooling. Now with your weight and Turbo size you shouldn't have to worry much about spooling up. You should be able to run a little lower ratio like a 46, 47, or 48 on the back if it doesn't cause it to spin. For now make sure your leaving the line with some boost. Don't be scared like I was at first to twist it a lot on the take off. Also fix the clutch issue and se how it does too.
 
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