Verdict on Vortec TPI?
Thread Starter
Instructor
Joined: Aug 2002
Posts: 131
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From: Camarillo CA
Verdict on Vortec TPI?
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Verdict on Vortec TPI? (sunrise.cm)
The only difference between the Vortec TPI baseplate and the OEM baseplate is the Vortec plate has the bolt holes properly located and angled for the Vortec heads. So basically what you're looking at there is what kind of power can be had from adding the Vortec heads to the motor, as that is what is effectively changing.
The stock L98 heads suck, but there is a lot of good work that can be done to them by a good port job (with access to a flowbench) When I ported my heads a few weeks ago, I dropped 0.7 second and gained 8 mph in the 1/4 (on a track that doesn't hook as well) The only other mod I had done to the car since it's previous best was a ZF swap, and the ZF has taller gears than the 4+3 which would have hurt the car's acceleration. I will be doing a gear swap this weekend to bring the net gear ratios back to stock, as well as putting in a stronger clutch. Then we'll see what the head porting really did to the car's power.
The stock L98 heads suck, but there is a lot of good work that can be done to them by a good port job (with access to a flowbench) When I ported my heads a few weeks ago, I dropped 0.7 second and gained 8 mph in the 1/4 (on a track that doesn't hook as well) The only other mod I had done to the car since it's previous best was a ZF swap, and the ZF has taller gears than the 4+3 which would have hurt the car's acceleration. I will be doing a gear swap this weekend to bring the net gear ratios back to stock, as well as putting in a stronger clutch. Then we'll see what the head porting really did to the car's power.
Racer
Joined: Oct 2001
Posts: 481
Likes: 0
From: Surrey BC
Re: Verdict on Vortec TPI? (CorvetteZ51Racer)
hey z51racer, by those numbers it looked like oyu gained ~75 hp by porting those heads (.1 sec or 1 MPH is worth about 10hp) I didn't think that these dport heads could get that good. :confused:
Drifting
Joined: Dec 2002
Posts: 1,861
Likes: 4
From: Houston TX
Re: Verdict on Vortec TPI? (Chief Muktar)
the estimates are that I did gain about 60-75 hp and about 60-75 lb-ft at the wheels from the port job. When I get the new clutch and gears (and rear tires :D ) installed, I plan on getting the car dynoed and will let you know what the gain was. Previous numbers were 228 rwhp and 336 rwtq on MSR's old dyno.
