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Ekliptix · 09-10-2018, 08:58 AM

A sluggish 14.5 at 90mph. Something needs some adjusting.

If I left it in Drive, it'd do 14.7 at 88, shifting really early around 4000rpm. I tried tightening the TV cable to the 700R4. It didn't seem to make a difference.
Manually shifting from 1-2-3, I was able to make it shift around 5500rpm which netted the 14.5 at 90mph.

Traction was not an issue. I left as hard as I could which was at the 2,400rpm the converter would let me. 2.0 60' every time.

Possible reasons:
- engine is not making the claimed 430hp so some adjustments need to be made.
- trans is robbing the power somehow.

A fellow at the track said his friend has a TCI 700R4 and they had to change the 'module' to a corvette module and it solve the low rpm shift points. I'll look into it.

In case y'all think I need a 'driver mod', I've been drag racing for 20 years and am used to cutting 1.7# 60' times with manual transmission cars trapping 125mph.

09-10-2018, 08:58 AM	#122
Ekliptix Registered User Join Date: Aug 2013 Location: Calgary, Alberta Posts: 674	Re: Install thread- Holley EFI Sniper on '72 402 big block A sluggish 14.5 at 90mph. Something needs some adjusting. If I left it in Drive, it'd do 14.7 at 88, shifting really early around 4000rpm. I tried tightening the TV cable to the 700R4. It didn't seem to make a difference. Manually shifting from 1-2-3, I was able to make it shift around 5500rpm which netted the 14.5 at 90mph. Traction was not an issue. I left as hard as I could which was at the 2,400rpm the converter would let me. 2.0 60' every time. Possible reasons: - engine is not making the claimed 430hp so some adjustments need to be made. - trans is robbing the power somehow. A fellow at the track said his friend has a TCI 700R4 and they had to change the 'module' to a corvette module and it solve the low rpm shift points. I'll look into it. In case y'all think I need a 'driver mod', I've been drag racing for 20 years and am used to cutting 1.7# 60' times with manual transmission cars trapping 125mph. __________________ 1972 Cheyenne Super SWB PS, PB, Tach, A/C, Tilt. Drivetrain: Built 402BB, TCI Streetfighter 700R4, 2,500 stall, Eaton posi, 3.73. Suspension/Chassis: ECE 4.5/6.5 drop, CPP nitrogen shocks, CPP front and rear sway bar, CPP cross members. Exhaust: 3" exhaust with x-pipe, Spintech 3000 mufflers, Hooker ceramic coated headers. Best 1/4 mile time: TBD.