Proven Power Adders - Single Item - Bolt Ons
Thread Starter
Melting Slicks
Joined: Aug 2004
Posts: 2,165
Likes: 950
From: Keizer Oregon
Proven Power Adders - Single Item - Bolt Ons
I've filtered through multiple threads and watched many Youtube videos and it's not clear if ANY C8 bolt ons or combinations of bolt-ons (obviously without a tune) actually "bolt on" proven repeatable extra power. I have seen examples of a few combos that cost many thousands of dollars, but after extensive dyno and field testing show little to no gains.
I am not new to Corvettes (My C8 HTC Z51 is my 4th after trading in my 2019 GS Manual) but previous generations were easy to add "bolt on and tune" components.
So: tell me about your personal experience (dyno proven would be ideal) with C8 bolt ons and if any of them have been significant additions to your C8 given no ability to tune the car.
My ideal goal with my HTC would be Exhaust/Intake type mods that hopefully gain back enough power to be equal to coupe performance (given the extra weight of the HTC- 77lbs)- perhaps REAL rear wheel 20-30hp
I can't find that this thread is exactly redundant to previous threads...If it is - please close this and provide links
I am not new to Corvettes (My C8 HTC Z51 is my 4th after trading in my 2019 GS Manual) but previous generations were easy to add "bolt on and tune" components.
So: tell me about your personal experience (dyno proven would be ideal) with C8 bolt ons and if any of them have been significant additions to your C8 given no ability to tune the car.
My ideal goal with my HTC would be Exhaust/Intake type mods that hopefully gain back enough power to be equal to coupe performance (given the extra weight of the HTC- 77lbs)- perhaps REAL rear wheel 20-30hp
I can't find that this thread is exactly redundant to previous threads...If it is - please close this and provide links
Last edited by oregonsharkman; Apr 9, 2022 at 11:41 PM.
What’s Next
Joined: Dec 2020
Posts: 1,293
Likes: 834
From: Reality
You are correct. The best bet is simply adding a good exhaust. It will free up decent power (maybe 10 whp), get some great sound, and save a lot of weight pending which one you get. If cats are up your ally you MIGHT net a few more whp but save some more weight. Anything after that is pure luxury until a tune ever presents itself.
Unless you want to drop 6-7K to drop the motor and have the heads ported which has proven to add 50-60whp we’re all pretty much waiting.
Unless you want to drop 6-7K to drop the motor and have the heads ported which has proven to add 50-60whp we’re all pretty much waiting.
Le Mans Master
Joined: Oct 2005
Posts: 5,053
Likes: 889
From: Tampa Florida
Hey Oregonsharkman, take a look at my post in the sticky section (Unofficial C8 Fast List). Well the only difference is that you have a Z51 HTC. I am not too keen about dyno results but mostly drag strip results. Having said that, I had only one occasion to take my base model HTC to the drag strip and was impressed for the first time out. I pretty much follow the guys with C8s at my track. There is one guy that I talk to and pretty much familiar with his bolt-ons. Not a HTC Z51 but just a Z51 with a high spoiler. His C8 with numerous runs at the in stock form best was 11.21@118. He later did the following mods.......ported intake manifold, 91 ported TB , Attack Blue Filter and AWE Exhaust system which resulted to a 10.93@122.51. The tires in use at the time was the Michilen 4S which probably gave him a better 60ft time. And yes I am aware that your car is the heaviest of the C8s. This info is only to give you an idea. My mods will probably be similar but with the 95 TB and without the AWE Exhaust system.
Thread Starter
Melting Slicks
Joined: Aug 2004
Posts: 2,165
Likes: 950
From: Keizer Oregon
Hey Oregonsharkman, take a look at my post in the sticky section (Unofficial C8 Fast List). Well the only difference is that you have a Z51 HTC. I am not too keen about dyno results but mostly drag strip results. Having said that, I had only one occasion to take my base model HTC to the drag strip and was impressed for the first time out. I pretty much follow the guys with C8s at my track. There is one guy that I talk to and pretty much familiar with his bolt-ons. Not a HTC Z51 but just a Z51 with a high spoiler. His C8 with numerous runs at the in stock form best was 11.21@118. He later did the following mods.......ported intake manifold, 91 ported TB , Attack Blue Filter and AWE Exhaust system which resulted to a 10.93@122.51. The tires in use at the time was the Michilen 4S which probably gave him a better 60ft time. And yes I am aware that your car is the heaviest of the C8s. This info is only to give you an idea. My mods will probably be similar but with the 95 TB and without the AWE Exhaust system.
Race Director
Joined: Sep 2016
Posts: 13,180
Likes: 10,528
Saw a post by one owner who did before and after dyno tests. He did an intake, exhaust and, IIRC, sport cats. Ended up gaining about 25 hp, which really isn't very much considering the effort involved.
Every mod company claims. it seems, 15-20 hp. But the mods aren't additive. You don't get 60 hp by adding three mods that each [claim to] deliver 20 HP.
Every mod company claims. it seems, 15-20 hp. But the mods aren't additive. You don't get 60 hp by adding three mods that each [claim to] deliver 20 HP.
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,102
From: Fulshear, TX
I'd agree with the full round of bolt-ons being worth approximately 20-25whp gains vs. stock.
I'm personally @ 450whp and think it's pretty well maxed out on the stock tune. I could maybe squeeze out a few more ponies with a catback system but I'm quite happy with the sound as-is (headers + cats w/NPP).
Sure, it was a lot of money considering, but I'm very happy with the results, the sound, and how it all looks. I also like just doing it! No regrets and would do it all over again and probably wouldn't change a thing
I'm personally @ 450whp and think it's pretty well maxed out on the stock tune. I could maybe squeeze out a few more ponies with a catback system but I'm quite happy with the sound as-is (headers + cats w/NPP).
Sure, it was a lot of money considering, but I'm very happy with the results, the sound, and how it all looks. I also like just doing it! No regrets and would do it all over again and probably wouldn't change a thing
Le Mans Master
Joined: Oct 2005
Posts: 5,053
Likes: 889
From: Tampa Florida
Right......each mod compliments the other. It just doesn't work that way by adding gains per mod. And actually 25 rwph does make a difference from stock. I don't rely on dyno numbers because to me it's just only very good tool to use. Example: The C8 I mentioned above only made 434 rwhp with basic mods.......same day and condition completely stock C8 made 423. The mods on the C8 were AWE Exhaust system, attack blue filter and 91mm ported TB. That was a 11 rwhp difference between the two C8's and both Z51's. When the modded c8 added the ported throttle body it picked up two tenths and two mph trap speed through the quarter mile. Those numbers definitely translated to a certain amount of horsepower in order to accomplish that feat. Having said that it was obvious that particular combo worked very well.
Note: So that same c8 completely stock went 11.30@118......modded it went 10.93@122.51.
I am willing to bet that those mods together were no more than 25 rwhp.
Note: So that same c8 completely stock went 11.30@118......modded it went 10.93@122.51.
I am willing to bet that those mods together were no more than 25 rwhp.
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Melting Slicks
Joined: Aug 2000
Posts: 2,431
Likes: 1,203
From: Early 2020 Z51 Coupe, Original Owner, Ahwatukee Foothills, AZ
I'd agree with the full round of bolt-ons being worth approximately 20-25whp gains vs. stock.
I'm personally @ 450whp and think it's pretty well maxed out on the stock tune. I could maybe squeeze out a few more ponies with a catback system but I'm quite happy with the sound as-is (headers + cats w/NPP).
Sure, it was a lot of money considering, but I'm very happy with the results, the sound, and how it all looks. I also like just doing it! No regrets and would do it all over again and probably wouldn't change a thing
I'm personally @ 450whp and think it's pretty well maxed out on the stock tune. I could maybe squeeze out a few more ponies with a catback system but I'm quite happy with the sound as-is (headers + cats w/NPP).
Sure, it was a lot of money considering, but I'm very happy with the results, the sound, and how it all looks. I also like just doing it! No regrets and would do it all over again and probably wouldn't change a thing
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,102
From: Fulshear, TX
What would be great is to line the cars up and see how they compare on a highway pull! Similar dyno results but totally different recipe to get there.
Melting Slicks
Joined: Aug 2000
Posts: 2,431
Likes: 1,203
From: Early 2020 Z51 Coupe, Original Owner, Ahwatukee Foothills, AZ
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,102
From: Fulshear, TX
Paragon's independent intake system testing:
Quick summary of peak numbers with gains, in order of appearance, so we have it documented:
Brand / WHP / WTQ (gains)
Brand / WHP / WTQ (gains)
- stock / 436 / 428
- K&N / 441 / 430 (+5/+2)
- aFe Pro5R / 441 / 429 (+5/+1)
- aFe ProDryS / 444 / 435 (+8/+7)
- Halltech / 443 / 428 (+7/+0)
- Corsa / 448 / 431 (+12/+3)
Racer
Joined: Feb 2020
Posts: 377
Likes: 435
I have every performance mod you can put on a C8 except for ported heads and can say that none have really done much of anything with regards to track results. The stock cats actually flow incredibly well because of their size, the sport cats end up just being about getting the sound right.
Some mods have increased throttle response slightly, some have made the car sound different, but from a seat of the pants perspective nothing has made a real impressive difference. However I'm confident my car is set up well for when tuning is available which is nice
Some mods have increased throttle response slightly, some have made the car sound different, but from a seat of the pants perspective nothing has made a real impressive difference. However I'm confident my car is set up well for when tuning is available which is nice
Instructor
Joined: Aug 2021
Posts: 200
Likes: 72
According to Lingenfelter, this will add 25 WHP...
Performance Design C8 Corvette Carbon pTR Intake Manifold LT2 (lingenfelter.com)
Performance Design C8 Corvette Carbon pTR Intake Manifold LT2 (lingenfelter.com)
Melting Slicks
Joined: Jun 2001
Posts: 2,266
Likes: 549
My dyno is 660 ft long ,up hill @ 6000+ DA. MPH is what I base my gains on. First test&tune 5/15/22 will see what a soler-socal port job added. Keep testing, dynos don't race & cars don't read magazines. As a group we will all make gains, and share results, And Learn.
Racer
Joined: Feb 2020
Posts: 377
Likes: 435
According to Lingenfelter, this will add 25 WHP...
Performance Design C8 Corvette Carbon pTR Intake Manifold LT2 (lingenfelter.com)
Performance Design C8 Corvette Carbon pTR Intake Manifold LT2 (lingenfelter.com)
Race Director
Joined: Jan 2014
Posts: 10,709
Likes: 7,102
From: Fulshear, TX
According to Lingenfelter, this will add 25 WHP...
Performance Design C8 Corvette Carbon pTR Intake Manifold LT2 (lingenfelter.com)
Performance Design C8 Corvette Carbon pTR Intake Manifold LT2 (lingenfelter.com)
This person independently dynod his. He saw between 0 and 5hp gains..
https://www.midenginecorvetteforum.c...tq-gains/page5
https://www.midenginecorvetteforum.c...tq-gains/page5
Le Mans Master
Joined: Oct 2005
Posts: 5,053
Likes: 889
From: Tampa Florida
I agree Kracka. What you are referring is where I want to start......ported intake manifold, the 87 mm ported throttle body to 91mm and the blue attack filter. Surprisingly those mods didn't show that much on the dyno but on the track almost 2 tenths and 2 mph in good air. Since you cannot tune this car, favorable air is your friend. Horrible air will kill your added horsepower mods in almost all instances.
