4v auto trans?
Thread Starter
2nd Gear Member
Joined: Mar 2007
Posts: 401
From: pa
4v auto trans?
What’s up guys, I recently had a 4v head swap done to my 98 gt. The car is different at a high rpm but almost seams sluggish for the first few thousand rpm’s. I have a auto trans with a shift kit and 3.73 gears, short tube headers with high flow cats 2 ½” exhaust and other stuff. The shop said im putting 264 hp on the ground but doesn’t feel much quicker then before. I don’t have pre swap #’s but my best old 2v npi ¼ mile time was 14.2 and haven’t made it to the track yet. I am looking for suggestions to get this thing jumping up to speed quicker. Thanks for any help
5th Gear Member
Joined: Dec 2004
Posts: 2,821
From: The Great Northwest
what 4v heads did you get? and by the first few thousand is that from 1-3 or like 3-5?
because most 4 valves dont have a great out ammount of bottom end, my car doesnt have much below 3 grand, i believe its just truly the cams and gearing. a lightweight flywheel and driveshaft will give you a lot of bottom end and make the car really responsive. i did that to my 01 gt 5spd car.
because most 4 valves dont have a great out ammount of bottom end, my car doesnt have much below 3 grand, i believe its just truly the cams and gearing. a lightweight flywheel and driveshaft will give you a lot of bottom end and make the car really responsive. i did that to my 01 gt 5spd car.
Last edited by I G Joe; Jun 20, 2009 at 11:45 AM.
Thread Starter
2nd Gear Member
Joined: Mar 2007
Posts: 401
From: pa
The trans is still stock, and all of the swap was from a 98 cobra “b” heads he still needs to send the dyno chart to me and I got the shortys put on parts and labor for $250 and am thinking of turbo charging.
It is sluggish before 3k, and will the lightweight flywheel and drive shaft really help that much for 0-100 mph speeds? What kind of ¼ mile times are you at before and after?
thanks
It is sluggish before 3k, and will the lightweight flywheel and drive shaft really help that much for 0-100 mph speeds? What kind of ¼ mile times are you at before and after?
thanks
2nd Gear Member
Joined: May 2003
Posts: 389
From: New Castle, Delaware
Just curious, what kind of tune was loaded into the car after the swap? Was the ECU changed out, or is it still the stock GT unit with a 4V tune? Sometimes just getting the computer matched up to the motor can take considerable tweaking on the tuners part. You also might want to shop around for an automatic tranny out of an 03/04 Mach 1, Marauder, or Aviator. Their stronger, and I think the gearing is different in them compared to the stock GT.
Last edited by Mach1man; Jun 22, 2009 at 09:27 AM.
Thread
Thread Starter
Forum
Replies
Last Post
Matt's 95 Stang
5.0L (1979-1995) Mustang
2
Oct 5, 2015 07:16 AM