[TheGrudge]

Greetings all,
I'm a long time late night reader of this forum but this is one of few posts.
I've posted previously on another forum but found the responses a little too
"Now listen here, sonny..." for my liking.
You never know who you're condescending to. Ahem.

Due to the birth of my second child two weeks ago ( It's a boy! ) my long term (20+ yrs) 70 GTO project is once again on hold. It's during these times that
the cheap/free stuff keeps the dream alive.
So, I thought I might list where I'm at and fish for some opinions/guesses/predictions while my beautiful family
absorbs 99.99% of my time, energy and money
( and rightly so ).

I'm looking to drive to and from my local track ( 1/2 hr ) and click off some
low to mid 11s a couple of times a month and cruise to the
beach for a burger ( also 1/2 hr ) on occasion.

Combo is as follows:
455 - 4.25 x 4.181 (467) 6.8" rods etc
4 bolt mains with Program caps
Lifter bore brace ( overkill but one less thing to worry about )
87cc E heads ported by JBP approx 300cfm / approx 10.25:1
Torker 2 ( suggestions on spacers? )
Carb shop stage 3 750 vac sec Holley ( 926cfm )
Comp Cams 290b6 solid / crower lifters
Comp gold 1.65 roller rockers
MSD ignition
Not sure Dougs 1 7/8" or MadDog 2" headers
3" full exhaust
TH400 - will be built by very experienced local race trans guy
Converter - plan to dyno motor and weigh car first but open to suggestions
9" rear 3.89 Detroit locker 35 spline axles etc
28" rear tyres
Tube upper and lower control arms front & rear
Moroso drag springs
Competition engineering adjustable shocks

I guess the car will weight maybe 3500-3600 + 220 for me
Soooooo.....
How much power will it make?
What ET/trap speed will it run?

I look forward to speculation/advice/criticism. Thanks!
Jordan

[steve25]

Well your headers are on the big side and that un-ported Torker II will not flow even 270 CFM in stock form.
Your average intake cfm with the lift of that cam will be around 260 to 265 so you should make some 550 hp.
Also dependant on what the heads accutally have for a Exh to Intake ratio you might want to play aorund with just 1.5 rockers on the exh side!

[firechickenman]

That combo is pretty similar to mine. I've never had it on a dyno but track times tell me it should be around 560 hp. I'm at 3700 lbs with me in it. Typically, it will run low 11s at 118. Good luck with your project and congrats on your son!

[chuckies76ta]

Just my thoughts Jordan. You don't need 2" headers. 1-3/4" is lots. 3" full exhaust will be nice.
3.89 gear with 28" tire will be the pits on the street for cruising. (too tall a gear). I would think a 3.42 would be alot better.
We run port matched torker 2 and 950 quickfuel carbs and run great on the street or strip.

I run a Torker 2 on my wife's 68 firebird with a one inch spacer. Car weights 3700 lbs and best so far has been 10.90 at 122 mph at sea level. The thing is a beast on the street. lots of power.

Engine should make an easy 560 hp and 600 torque. Low to mid 11's all day long.

Charles

[TheGrudge]

Thanks guys, looks like I'm kinda on the right track. Haven't purchased headers yet, definitely looking for input there. More than likely will have to modify them either way as car is right hand drive ( converted as a new car ) - I thought the over the frame style may need fewer mods thus I have considered MadDogs.
I'm happy to use a taller tyre for street use if need be, diff is assembled and ready to run.

[mike leech]

Originally Posted by TheGrudge

Thanks guys, looks like I'm kinda on the right track. Haven't purchased headers yet, definitely looking for input there. More than likely will have to modify them either way as car is right hand drive ( converted as a new car ) - I thought the over the frame style may need fewer mods thus I have considered MadDogs.
I'm happy to use a taller tyre for street use if need be, diff is assembled and ready to run.

2" are too big.....1 3/4 ideal as stated. 1 7/8 max

[ta man]

Experiment with spacers on the torker 2 I'm using a one inch Wilson four hole tapered(worth about 2 tenths over none at all),gearing is a bit high for a street car,pick a custom made convertor,I use a Continental,my build is close ....with 3.08 gearing and a 3200 convertor at 3900 lbs I run 11.40's at 118 plus with a untouched torker 2.

[TheGrudge]

[QUOTE\] I run 11.40's at 118 plus with a untouched torker 2.[/QUOTE]

I was going to port match mine - worth the effort at my ( estimated ) power level?

[ta man]

Originally Posted by TheGrudge

[QUOTE\] I run 11.40's at 118 plus with a untouched torker 2.

I was going to port match mine - worth the effort at my ( estimated ) power level?[/QUOTE]

I believe its choking mine..how much I don't know until its opened up and tested.

[TheGrudge]

Originally Posted by mike leech

2" are too big.....1 3/4 ideal as stated. 1 7/8 max

Product Information
Part
35137
Pontiac GTO 1970
CID: 350, 400, 455, 428, 389
1 3/4" x 1 7/8" 400-455 3" Edelbrock Heads


Header Style Stepped Conventional
Exhaust Exit Under Chassis Exit
Collector Size 3"
Collector Attachment Weld-On Style Collectors. Headers also come with 3-Bolt Triangular flange Street Hook-ups
Head Flange Gasket 18074
FLANGE Thickness 3/8"
Contents Pair of Headers, Gaskets & Mounting Hardware
Head Flange Style Edelbrock Head
Header Port Shape Edelbrock Heads
Tube Design Stepped Conventional
Tube Size 1 3/4" x 1 7/8"

What about these from Hedman?

[BruceWilkie]

Originally Posted by TheGrudge

Product Information
Part
35137
Pontiac GTO 1970
CID: 350, 400, 455, 428, 389
1 3/4" x 1 7/8" 400-455 3" Edelbrock Heads


Header Style Stepped Conventional
Exhaust Exit Under Chassis Exit
Collector Size 3"
Collector Attachment Weld-On Style Collectors. Headers also come with 3-Bolt Triangular flange Street Hook-ups
Head Flange Gasket 18074
FLANGE Thickness 3/8"
Contents Pair of Headers, Gaskets & Mounting Hardware
Head Flange Style Edelbrock Head
Header Port Shape Edelbrock Heads
Tube Design Stepped Conventional
Tube Size 1 3/4" x 1 7/8"

What about these from Hedman?

Looks like a good place to start IMO

[TheGrudge]

Thanks Bruce. Has anyone used these in a similar application?

[Region Warrior]

"Exhaust exit under chassis"

1/2 hour one way?

Had full 3" with turn downs exit under rear seat.
Highly recommend at least out in front of rear tires.
Cruising is so much enjoyable.

[ta man]

Originally Posted by Region Warrior

"Exhaust exit under chassis"

1/2 hour one way?

Had full 3" with turn downs exit under rear seat.
Highly recommend at least out in front of rear tires.
Cruising is so much enjoyable.

x2
I drive almost 100 miles to the one dragstrip I frequent,my car is pretty quiet at 60 to 70 mph,3 inch x pipe,Ultraflows,2.5 inch tailpipes

[TheGrudge]

Originally Posted by Region Warrior

"Exhaust exit under chassis"

1/2 hour one way?

Had full 3" with turn downs exit under rear seat.
Highly recommend at least out in front of rear tires.
Cruising is so much enjoyable.

Yes, 1/2 hour one way. Unlikely to get to 70mph.
Unfortunately local regulations don't allow exhaust exiting
under an opening window unless factory fitted.
Seems it wouldn't be right not to have quad tips exiting
from the valance cutouts on a '70 GTO...

[TheGrudge]

Any header recommendations 68-72 A body 500-600hp range?