Stroke vs Head(s) turbo application
Thread Starter
7 Second Club
iTrader: (11)
Joined: Jul 2002
Posts: 8,758
Likes: 9
From: Port Tobacco, MD
Stroke vs Head(s) turbo application Which one is more important in the final power output of a turbocharged application? If you could go with only one or the other which one would you choose?
1)
Stroker with mild heads
2)
Standard stroke with the best heads on the market.
1)
Stroker with mild heads
2)
Standard stroke with the best heads on the market.
Good question. I would like to hear many answers on this.
It's obvious that stroker + the best heads would be nice, but to what degree and in what way would one change have impact compared to the other?
It's obvious that stroker + the best heads would be nice, but to what degree and in what way would one change have impact compared to the other?
Bore has a significant impact on power. If I had a bunch of money I would be building a 4" bore 3" stroke 302ci LS2 block engine with L92 heads. Rev it to 8000RPM.
Andrew
Andrew
Originally Posted by cablebandit
i would guess neither is BEST...just kinda equal....pick your poison
Originally Posted by Project GatTagO
Bore has a significant impact on power. If I had a bunch of money I would be building a 4" bore 3" stroke 302ci LS2 block engine with L92 heads. Rev it to 8000RPM.
Andrew
Andrew
Trending Topics
Teching In
Joined: Dec 2006
Posts: 32
Likes: 0
The way i look at it is, Big bore, you are going to get the maximum out of a given set of heads. as the valve shrouding will be much less than with a smaller bore. All of your top level motorsports use the largest bore they can and then use whatever stroke they need to get to the cubic inch limit allowed by rules. Ex. NHRA Pro Stock 4.680" bore and around 3.62" stroke. NASCAR 4.190" bore and 3.25" stroke. And IHRA Pro Stock uses bores up to 4.800". So I quess these types of teams put more value in bore. But, you cant beat Bore and Stroke. So me Personally, I would use the largest bore possiible then choose crank stroke to determine cubic inch and what the final Comp ratio will be, so it will be low enough to be able to be turbocharged.
To give you an idea of what im talking about, Im building a TT500+ inch BBC, with less stroke Than what you guys use in a 402 LS1.
To give you an idea of what im talking about, Im building a TT500+ inch BBC, with less stroke Than what you guys use in a 402 LS1.
Last edited by 509TURBOFIREHAWK; Jan 16, 2007 at 06:16 PM.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
if your gonna use the turbo to make power, the path of least resistance I would think would be your heads...
From what I understand, you can make similar power with different CI motors, but the area under the curve is different.
Id say stick with smaller bore, put on some bad *** heads and max that turbo out.
From what I understand, you can make similar power with different CI motors, but the area under the curve is different.
Id say stick with smaller bore, put on some bad *** heads and max that turbo out.
TECH Addict
Joined: Jul 2005
Posts: 2,153
Likes: 3
Originally Posted by DrTurbo
Will depend on the turbo........to many variables left unanswered.
Turbo selection
Intended use
Intended boost level / fuel
...just to name a few.
Mike
Originally Posted by 427
The whole package must work, but if I had to answer it would be better heads everytime.
Kurt
Kurt
And whats up with this smily?
I like it 
TECH Fanatic
Joined: Mar 2002
Posts: 1,169
Likes: 0
I too would say it is the whole combo. When you look at some of the record setter's combos, nothing stands out. Wolfes motor was a 4.030 bore, 3.75 stroke with some TW R heads that flowed around 330. None of that is special...just a good cam, converter and tune is what really matters IMO. Job Jr ran high 7's with heads that barely flowed over 300....it was the combo.
I would say better heads. I'm always reading how these relativly small motor Mustangs (Mid 300 and lower cubes) are having no problem going into the 8's and 7's. That tells me its in the rest of the combo thats making it work. Look at Kempfs Camaro. Bottom 8's on a 370 cube iron block and no trouble spooling a 101. Not bad if you ask me!
TECH Addict
Joined: Jul 2005
Posts: 2,153
Likes: 3
Originally Posted by F8LWS6
I would say better heads. I'm always reading how these relativly small motor Mustangs (Mid 300 and lower cubes) are having no problem going into the 8's and 7's.
It's pretty well known, that for max absolute power, some turbo's do better on smaller cid but with more boost. So, the 331 cid mustangs running T-76 turbo's have an advantage, but keep in mind they're running 25+ psi boost and race gas.
Err.....Well I meant more along the lines of this :
http://www.candcmotorsport.com/index.html
331 with 96 MM turbo making well over 1200 horse running 7.71@188mph on drag radials.
http://www.candcmotorsport.com/index.html
331 with 96 MM turbo making well over 1200 horse running 7.71@188mph on drag radials.
Originally Posted by engineermike
That's where the goals, gas, and turbo selection come in.
It's pretty well known, that for max absolute power, some turbo's do better on smaller cid but with more boost. So, the 331 cid mustangs running T-76 turbo's have an advantage, but keep in mind they're running 25+ psi boost and race gas.
It's pretty well known, that for max absolute power, some turbo's do better on smaller cid but with more boost. So, the 331 cid mustangs running T-76 turbo's have an advantage, but keep in mind they're running 25+ psi boost and race gas.
If you have a stocker and a stroker pumping the same air through them, (smaller cubes would need a little more boost to acheive the same airflow as larger cubes) I would assume the stocker would be better. A de-stroker I think would be better than a stroker in boost applications, less rotating mass and I dont think you really need a stroker for torque in a boost app either. Max bore would be best and minimum stroke.
Just my opinion.
Just my opinion.