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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
I’ve been trying to find ways to make more power without tearing into the motor but I kept coming back to swapping cams. After a lot of back and forth research, I decided on the new TSP 4.2 grind. It’s one of the most aggressive OTS grinds out there, under .660 lift. I had Pat G spec me a custom cam and still, ultimately, landed on the TSP cam.
Unfortunately, I don’t have a true back-to-back comparison. I changed to a vararam Intake after my initial tune and never put it back on the dyno to see the difference. From everything I’ve seen, the vararam dynos 10-15whp less, on average.
Lost a little torque down low over the last setup but carried power further up.
Here’s the SAE graph
Overall, I’m happy with the swap. Drivability suffered a little bit. I can probably have it smoothed out a little more but it’s not a huge deal. Idle sounds pretty damn good compared to the last cam.
Gained about 1.5 cars in Mexico against a comparable, consistent car. Can’t complain with those results.
Very cool! I have a custom cam from performance hq in San Antonio that shares a very similar grind as tsp 4.2. I made 585 without milled heads and on 93 octane with 75% humidity. Hope to get over 600 with e85 and better weather. I didn't know you could mill heads .50 I thought the most you could go it .30
Very cool! I have a custom cam from performance hq in San Antonio that shares a very similar grind as tsp 4.2. I made 585 without milled heads and on 93 octane with 75% humidity. Hope to get over 600 with e85 and better weather. I didn't know you could mill heads .50 I thought the most you could go it .30
Are you from SA?
I don’t think you’ll gain 15whp on e85 unless, for whatever reason, your timing table was not maxed out for pump gas.
From what I’ve read, you can go .060”, flat mill, without having issues with the intake manifold lining up. You can angle mill the heads up to 13.8 compression, maybe even more.
You can but it hurts flow and is of diminishing returns. The best way to bump compression that high is with different piston profile.
Aftermarket heads are the next step, if you want to go there.
Mamo TFS are on the list. Just not “next”. I’ll likely try a 2” header, different axle-back, and more weight reduction. Still waiting on the release of the gearsets and trying to decide between a 3.90 and 4.10.
I don’t think you’ll gain 15whp on e85 unless, for whatever reason, your timing table was not maxed out for pump gas.
From what I’ve read, you can go .060”, flat mill, without having issues with the intake manifold lining up. You can angle mill the heads up to 13.8 compression, maybe even more.
I don’t think you’ll gain 15whp on e85 unless, for whatever reason, your timing table was not maxed out for pump gas.
From what I’ve read, you can go .060”, flat mill, without having issues with the intake manifold lining up. You can angle mill the heads up to 13.8 compression, maybe even more.
I gained 14 rwhp/ 17 rwtq on an NA 500 hp LS3 pretty much across the entire rev range, FYI. It's a BIG 14/ 17 too as the motor runs much 'sharper' on the E85 it's very noticeable.
I gained 14 rwhp/ 17 rwtq on an NA 500 hp LS3 pretty much across the entire rev range, FYI. It's a BIG 14/ 17 too as the motor runs much 'sharper' on the E85 it's very noticeable.
Was your pump gas timing maxed out? Heads milled at all? There are plenty other benefits to e85 than just power.
I’ve been trying to find ways to make more power without tearing into the motor but I kept coming back to swapping cams. After a lot of back and forth research, I decided on the new TSP 4.2 grind. It’s one of the most aggressive OTS grinds out there, under .660 lift. I had Pat G spec me a custom cam and still, ultimately, landed on the TSP cam.
Unfortunately, I don’t have a true back-to-back comparison. I changed to a vararam Intake after my initial tune and never put it back on the dyno to see the difference. From everything I’ve seen, the vararam dynos 10-15whp less, on average.
Lost a little torque down low over the last setup but carried power further up.
Here’s the SAE graph
Overall, I’m happy with the swap. Drivability suffered a little bit. I can probably have it smoothed out a little more but it’s not a huge deal. Idle sounds pretty damn good compared to the last cam.
Gained about 1.5 cars in Mexico against a comparable, consistent car. Can’t complain with those results.
Not sure what to do next.
just installed the 4.2 TSP. Curious what pushrod length you went with?
10-22-2017, 02:35 PM
Texas Speed 4.2 cam results
