C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
Sponsored by:
Sponsored by:

Would it be worth it

Thread Tools
 
Search this Thread
 
Old Jul 16, 2017 | 06:11 PM
  #1  
mvette76's Avatar
mvette76
Thread Starter
Racer
15 Year Member
 
Joined: Nov 2007
Posts: 350
Likes: 0
From: coon rapids mn
Default Would it be worth it

Right now I have a 454 in my vette that has been worked over a little bit and made 570hp on the engine Dyno and runs pretty strong but as always I want more! The engine has kb hyperpereutectic pistons that have a small dome for the 290 casting chevy heads I was thinking of pulling the motor out new forged pistons and upgrading to a 265 Cnc afr heads while in the motor put arp studs in the rods and arp studs or bolts in the mains (2 bolt) I have a roller valve train with a Straub hydraulic roller cam with .620 lift my heads flow a little over 300 cfms don't remember exactly plus the weight saving going aluminum head
Reply
Old Jul 16, 2017 | 06:53 PM
  #2  
cv67's Avatar
cv67
Team Owner
15 Year Member
 
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Default

if youre changing pistons put a bigger arm in it, little more head too
heads will help for sure but if youre really wanting more that stroke will do it (combined)!

Last edited by cv67; Jul 16, 2017 at 06:53 PM.
Reply
Old Jul 16, 2017 | 07:33 PM
  #3  
mvette76's Avatar
mvette76
Thread Starter
Racer
15 Year Member
 
Joined: Nov 2007
Posts: 350
Likes: 0
From: coon rapids mn
Default

Originally Posted by cuisinartvette
if youre changing pistons put a bigger arm in it, little more head too
heads will help for sure but if youre really wanting more that stroke will do it (combined)!
I really want to change as little as possible $ is tight that's why I only want to change pistons to get me the compression I would loose going from the small chambers to the afrs
Reply
Old Jul 16, 2017 | 07:43 PM
  #4  
Pop Chevy's Avatar
Pop Chevy
Le Mans Master
Supporting Lifetime
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Apr 2001
Posts: 5,436
Likes: 1,253
From: Sarver Pa
2021 C1 of the Year Finalist - Modified
Default

I don't know that I would want to go to 600 hp with a 2 bolt main block. If anything I would put a set of alum heads on it and not too big. 265's sound too big to me unless you want to turn a lot of rpm. What rods are in it ?

Last edited by Pop Chevy; Jul 16, 2017 at 07:43 PM.
Reply
Old Jul 16, 2017 | 07:52 PM
  #5  
dmaxx3500's Avatar
dmaxx3500
Team Owner
15 Year Member
Liked
Loved
Community Favorite
 
Joined: Jan 2008
Posts: 30,894
Likes: 1,189
From: chicago
Default

ive got a couple 588'' bbc's,alum heads,1250 dom carbs,roller cams,,10-1 run on pump gas,,made 750hp,you need these,dyno/break-in time only


and you can buy these cheaper then going thru you motor

Last edited by dmaxx3500; Jul 16, 2017 at 07:53 PM.
Reply
Old Jul 16, 2017 | 08:52 PM
  #6  
mvette76's Avatar
mvette76
Thread Starter
Racer
15 Year Member
 
Joined: Nov 2007
Posts: 350
Likes: 0
From: coon rapids mn
Default

Originally Posted by dmaxx3500
ive got a couple 588'' bbc's,alum heads,1250 dom carbs,roller cams,,10-1 run on pump gas,,made 750hp,you need these,dyno/break-in time only


and you can buy these cheaper then going thru you motor
This is something I would puts on over the winter and spread the cash flow over a few months even though your offer is tempting just not in the cards
Reply
Old Jul 17, 2017 | 08:06 AM
  #7  
Tiger Joe's Avatar
Tiger Joe
Drifting
Liked
Loved
Community Favorite
Top Answer: 1
 
Joined: Nov 2016
Posts: 1,960
Likes: 579
From: Pittsburgh PA
Default

you can't just change out main bolts for studs. you need to have the mains checked and then likely line honed.


weight savings of aluminum heads would be pretty decent. if I remember correctly I think a set of bbc aluminum heads weigh the same as 1 iron head.


most people will say 600 is as far as you want to push a 2 bolt block. but you could have drilled for 4 bolt mains.


you don't mention what kind of rods you have?


I did a quick search and looks like both the 290 heads you have now and the 265 AFRs have 100cc chambers, you could probably just throw a set of heads on, pick up some power, plus weight savings. other than that, everything else you mention well you're basically doing a full engine rebuild. Once you get bigger heads then you are gonna want a bigger cam, yada, yada, yada.


not trying to be an *** here, but how much of that 570 are you actually putting to the pavement? you already mentioned money twice in this thread, and everything you mentioned in your first post is NOT cheap. Your $$$ would probably be better spent on getting that power to the ground.
Reply
Old Jul 17, 2017 | 08:22 AM
  #8  
gungatim's Avatar
gungatim
Burning Brakes
15 Year Member
All Eyes On Me
Liked
Loved
 
Joined: Apr 2008
Posts: 1,222
Likes: 93
From: shelbyville West Michigan
Default

tight on money, and want to do all that work for a 30hp gain?

I would just learn to be happy with 570 hp and put any money toward traction as stated above.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-1

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-2

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-3

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-4

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-5

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-6

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-7

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-8

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-9

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
Old Jul 17, 2017 | 11:29 AM
  #9  
Les's Avatar
Les
Race Director
25 Year Member
Liked
Loved
Community Favorite
 
Joined: Dec 1999
Posts: 11,096
Likes: 990
From: Sierra Foothills CA
Default

What kind of tires are you running out back?
Reply
Old Jul 17, 2017 | 11:51 AM
  #10  
Kacyc3's Avatar
Kacyc3
Drifting
10 Year Member
Liked
Loved
 
Joined: Jun 2012
Posts: 1,990
Likes: 183
From: Port St. Lucie Fl
Default

Seems like alot of work for a little gain. Have you looked at what it would cost to add a supercharger?
Reply
Old Jul 17, 2017 | 12:22 PM
  #11  
mvette76's Avatar
mvette76
Thread Starter
Racer
15 Year Member
 
Joined: Nov 2007
Posts: 350
Likes: 0
From: coon rapids mn
Default

Originally Posted by Tiger Joe
you can't just change out main bolts for studs. you need to have the mains checked and then likely line honed.


weight savings of aluminum heads would be pretty decent. if I remember correctly I think a set of bbc aluminum heads weigh the same as 1 iron head.


most people will say 600 is as far as you want to push a 2 bolt block. but you could have drilled for 4 bolt mains.


you don't mention what kind of rods you have?


I did a quick search and looks like both the 290 heads you have now and the 265 AFRs have 100cc chambers, you could probably just throw a set of heads on, pick up some power, plus weight savings. other than that, everything else you mention well you're basically doing a full engine rebuild. Once you get bigger heads then you are gonna want a bigger cam, yada, yada, yada.


not trying to be an *** here, but how much of that 570 are you actually putting to the pavement? you already mentioned money twice in this thread, and everything you mentioned in your first post is NOT cheap. Your $$$ would probably be better spent on getting that power to the ground.
I was trying to simplify the rebuild I know it will need to bring it to machine shop for work and I mentioned the money because I know how these threads go! I thought the afrs had 112cc chambers
Reply
Old Jul 17, 2017 | 02:09 PM
  #12  
Tiger Joe's Avatar
Tiger Joe
Drifting
Liked
Loved
Community Favorite
Top Answer: 1
 
Joined: Nov 2016
Posts: 1,960
Likes: 579
From: Pittsburgh PA
Default

i had a big long reply typed out and then it wouldn't let me post so here is a shorter version


you are correct its 110cc i read the wrong line.


You are basically talking about a complete engine rebuild. going to have the block stripped for a line hone. all new gaskets, check all the bearings for wear. then you'll likely want a bigger cam after you get the heads. you haven't said what crank and rods you have now, can they handle any more power?


I saw an old thread where you said ran a 8.0 in the 1/8. you aren't using the power you have at that speed, so have you done anything to improve traction since then?


if you just want a high hp number on paper then yes afr heads are the way to go. if you want to go faster, I would put some $$$ into suspension/drivetrain to make what you have more usable, otherwise you might just make it easier to do burnouts
Reply
Old Jul 17, 2017 | 02:35 PM
  #13  
Richard Daugird's Avatar
Richard Daugird
Melting Slicks
Liked
Loved
Community Favorite
Top Answer: 1
 
Joined: Dec 2015
Posts: 3,181
Likes: 732
From: Texas City, TX Texas
Default

Seems to me 570 H.P. would surely blow the rear tires out...
Reply
Old Jul 17, 2017 | 03:27 PM
  #14  
mvette76's Avatar
mvette76
Thread Starter
Racer
15 Year Member
 
Joined: Nov 2007
Posts: 350
Likes: 0
From: coon rapids mn
Default

It's more about loosing the weight of the cast iron head and maybe a little more hp when I ran the 8.0 it had a 3310 Holley on it no spacer and the hood was right on top of the carb also I was using a borrowed m20 from my dads 66 vette so I didn't want break it it now has a 850 ultra hp and a tko 600
Reply
Old Jul 17, 2017 | 06:22 PM
  #15  
suprspooky's Avatar
suprspooky
Burning Brakes
 
Joined: Jul 2016
Posts: 767
Likes: 74
From: Blaine MN
Default

I'm in the midst of a similar build, 427 L71 stroked to 460. I don't have Dyno numbers yet (waiting on Icon -18cc pistons). I'm also using a Straub Hyd. roller (.620/233). I already have the 265 AFR's (didn't weigh them yet, but soon). My 68 rect. port heads weighed 71 Lbs each. I'm in Blaine, MN, we're almost neighbors. I'd like to chat sometime soon about your experience with the TKO.
Reply
Old Jul 17, 2017 | 07:49 PM
  #16  
mvette76's Avatar
mvette76
Thread Starter
Racer
15 Year Member
 
Joined: Nov 2007
Posts: 350
Likes: 0
From: coon rapids mn
Default

Originally Posted by suprspooky
I'm in the midst of a similar build, 427 L71 stroked to 460. I don't have Dyno numbers yet (waiting on Icon -18cc pistons). I'm also using a Straub Hyd. roller (.620/233). I already have the 265 AFR's (didn't weigh them yet, but soon). My 68 rect. port heads weighed 71 Lbs each. I'm in Blaine, MN, we're almost neighbors. I'd like to chat sometime soon about your experience with the TKO.
anytime you want chat about cars I'm in! I go to the anoka car show a lot if I'm not there my old man is and he has a 427 rally red 66 with a tko500
Reply
Old Jul 17, 2017 | 08:40 PM
  #17  
TimAT's Avatar
TimAT
Le Mans Master
15 Year Member
Liked
Loved
 
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
Default

I went with Brodix Race-Rite heads- 294cc intake and 115cc chambers. No hassle with exhaust ports either. Stock location. I did have to grind a bit on the headers to clear the head bolts. Compression works out to 10.5 so it's pump gas day.
Reply

Get notified of new replies

To Would it be worth it





All times are GMT -4. The time now is 06:24 PM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE