Z-BOSS

I got an option on buying either one used. Just curious.

Chuck Everly

The 23* head is more like a stock replacement. The G2 twisted wedge is a higher performance head.

At least that is the way I understand it.

You may want to stay away from the early Twisted Wedge heads, they had a lot of quality problems.


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88 IROC convertible
-=ICON Motorsports=-

89ProchargedROC

do you know who preston smith is?

305
stock TPI
T-trim
Trickflow 23*

9.90s

Z-BOSS

No, who........

89ProchargedROC

that was his old setup....what you quoted. he ran those heads and went 9.90s. his car was the one advertised in the vortech ads

MikeH

iTrader: (10)

Dont forget...There are two versions of the 23* head now. They are offering a 215cc 23* head also. I havent seen any flow or power numbers from them. 215cc runner should work well with the larger smallblocks like the 400.



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Black 90 IROC, L98, A4, 323 gear. SuperRamed 406 in the works!

89ProchargedROC

actually that is a toatally different head all together. that is there "R" series head for small block chevy

LIFORM383

You would want to buy the 23 degree head. The intake volume is right around 200cfm and the cc size is relatively close to stock.

89ProchargedROC

i'm a little confused by what you mean here.

the stock intake port cc on a l98 head is 165cc or 170cc if i remember right and both the twisted wedge and 23* have 195cc intake ports and the cfm on the 23* heads on the intake i .500 lift is close to 220 not far behind the AFR's

Z-BOSS

Well I still running the long runner set up. Except with slp runners and ported the hell out of everthing except the heads.
The heads have been bowl ported though.

By the way I choose the twisted wedge heads.
I kinda wanted to try something different. We'll see how every thing goes in a week.

GregWestphal

iTrader: (1)

What LIFORM383 meant by "cc size" is combustion chamber size. The TF 23* heads have the same comb. chamber size (64 cc, as in cubic centimeters) as the stock L98 iron heads. Yes, the intake port size is 195 cc as 89ProchargedROC stated.

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Greg Westphal
'87 IROC 305TPI/A4

jimbo

I've run both heads on my '91. The twisted wedge heads were also available in a 64cc version. The downside to the TFS TW centerbolt heads is that you have to gut your valve covers to clear the rockers properly, and you're seriously limited on aftermaket rocker selection. With the 23 degree heads and the Crane Gold 1.6 roller rockers the stock valve covers work without modification, and you can also order them CNC ported, if you don't want to mess with them yourself.

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jimbo

Mosquito Coast F-Body Association (MCFBA)

1991 Formula SLP350
1999 Trans Am Firehawk

IrocStan

Did you notice a performance difference between the 2 heads? Which ones did you like better? What kind of mods do you have?
thanks


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87 IROC 350
13.94@103mph
Check out my new web page.
http://austinsiroc.homestead.com/Home1.html

jimbo

...I haven't dyno'd my car with the new heads yet, and to be honest, when I changed the heads I changed the cam and rockers too. so I really wouldn't be able to give you a viable comparative hp analysis between the two versions, but as far as the installation of the two, including the adjunct work that needs to be performed to complete the installation of the heads and aftermarket rockers, I would definitely recommend you go with the 23 degree heads. IMHO they are a cut above the twisted wedge version...especially the CNC ported ones...



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jimbo

Mosquito Coast F-Body Association (MCFBA)

1991 Formula SLP350
1999 Trans Am Firehawk

Z-BOSS

is there a special tool needed to bolt down the head bolts for the twisted wedge heads.

I had to make one for mine. Very tight spaces.

Artie@TFS

Here are some specs for you on the 23* head:
Intake runner: 195cc
Combustion chamber: 64cc or optional 72cc
Valve angles: 23* (Same as stock)
Sparkplugs:

Artie@TFS

Here are some specs on the 23* heads:
Intake Runner: 195cc.
Combustion chambers: 64cc or optional 72cc.
Valve angles: 23* (same as astock).
Sparkplugs: Angled.
Valves: 2.02" Intake / 1.60" Exhaust, SST.
Guides: Manganese Bronze.
Seals: Viton.
Flowbench Data:
Intake valve Exhaust valve
.100 = 51 .100 = 58
.200 = 136 .200 = 98
.300 = 191 .300 = 136
.400 = 230 .400 = 163
.500 = 253 .500 = 177
.600 = 254 .600 = 189
tests done at 28" water psi

Here are some specs on the G2 TW:
Intake runner: 190cc.
Combustion chamber: 67cc.
Valve Angles: 16* Intake & 18* Exhaust.
Sparkplugs: Angled.
Valves: 2.02" Intake & 1.60" Exhaust, SST.
Guides: Powdered Metal, Smooth bore.
Seals: Viton.
Flowbench Data:
Intake Valve Exhaust Valve
.100 = 68 .100 = 53
.200 = 144 .200 = 106
.300 = 206 .300 = 144
.400 = 242 .400 = 173
.500 = 253 .500 = 195
.600 = 257 .600 = 205
Tests done @ 28" water psi

Give me a call @ 330-630-1555 Ext 6324 if you need any questions answered regarding our products......