Don Terrill’s Speed-Talk

have a engine that has these heads onit ,they were ported and flow 317 at .700 was wondering whats the best flow numbers and hp you have seen these heads make and who did the work? thanks

How close is a Pro 1 to an Iron Eagle? Ive taken the Iron Eagle to 340cfm and 2 horse per cube with a Super Vic and a 4150 on gas. It took lots of trial and error over several years racing in one class and continually fine tuning the combo. Looking at the port shape and numbers on the flow bench it doesnt really make sense that these heads can make that kind of power. I dont understand it all myself.

Denis

Which castings are these pro1s? Are they recent? by that i mean purchased within the last 2years? The newer ones i found to be a better foundation to work with, but never the less, with good effort, (welded pinch, larger intake valve and heavy porting) you CAN achieve an honest 340-345cfm @.750-.800"
230-235cfm on exh.. (same lifts)

HP production? well say on a 406-440" deal, with a well ported intake and enough cam, and great bottom end you could make 780HP all day long.....

Mike Theroux
www.mikesportingservice.com

slow stang wrote:have a engine that has these heads onit ,they were ported and flow 317 at .700 was wondering whats the best flow numbers and hp you have seen these heads make and who did the work? thanks

it depends on if a particular FlowBench reads high or low,
...and more importantly Flow Numbers don't tell the entire story !

the Dart Pro 1 aluminum 215 or 235 CC Heads
can be made to make "honest" 750+ HP , it just depends on combo.

i posted a 434cid Combo with 756 HP long time ago on SpeedTalk



it ran 9.44 ET on motor only !



that Engines been together now for almost 3 years
..well almost...the ShortBlock is almost 3 years
its still making around 740's Peak HP

i had an update from Danny
he purchased a new Race Car,
Danny Durand's new 1996 Beretta

Motor only Run

2450 Lbs w/Driver
4.56 gears
32x14x15 Tires
14x15 Rims
4400 NOS Converter ( but no NOS was used )
7700 Shift
1.80 1st Gear
Hood Scoop

Feb 24, 2009 State Capitol Mardi Gras Race
11:55 AM Run
1.296
3.600
5.538
126.61
7.223
8.655
156.95

316 Ft DA
30.27 Barometer
64.9 degF
44.1 Dewpoint
47.0 % RH
SSE 8.1 MPH Winds

Simulation Pic in the 3200 Lbs Blazer




Dyno Test

I agree 100%, it's all in the combo. A Induction system that is perfect will help for sure if the combo is not perfect. Tunning as well as other factors come in to play with making power and ET.

Those heads can make some stem if done correct thats for sure.

Good Luck, T

another Dyno test of Dart Pro-1 alum Heads

these Heads make serious HP !!

no problem running 9.50's to 9.60' in 3200 lbs Car on 93 Pump Gas


Exxon 93 Prem Pump Gas 711.3 Peak @ 7600

July 15, 2008 Chris and Eric Vardnou 4.155x3.875=420.4 CID

ProSystems 1300 w/Power Valve
Dart Little-M Block std Cam location + size
Callies Magnum Crank
BME 5.850 alum rods
Diamond flat-top w/Gas ports 11:1 CR
Jesel Belt
Moroso 4-Vane enhanced
Chris Dyno Headers 2.000/2.125 4.000 Collector
36 BTDC Exxon 93 Prem
.025 hot lash
Royal Purple 5W/20 6 qts Hamburger no-kickout
-----------------------------------------
154 cranking psi
38 btdc from 36
83/93 from 86/96
40 btdc from 38
81/91 from 83/93
put on Meaux open hole carb spacer in place of Clover-Leaf spacer

Larry
Was that pump gas build one of yours or did you only dyno it?
Can you share any details on the heads? Must be rather large to peak at 7600rpm on 420".

where did you get the water pump plates from in the picture?

dat383 wrote:where did you get the water pump plates from in the picture?

those are from CSI, although i've made a few pairs in my Shop

Fatman

Larry
Was that pump gas build one of yours or did you only dyno it?
Can you share any details on the heads? Must be rather large to peak at 7600rpm on 420".

C and S Performance built the shortblock + assembly
i just Ported the Heads + Manifold and Dyno testing

i port both the 215 and 230cc to same Port Shape which is 240CC final
Entry matches FelPro # 1206

the Pump Gas 420cid 711.3 HP engine
was built for a Customer who didn't want to buy Race Gas
..sort of like see how much HP you can get me on Exxon 93 prem deal.

____________________________


another update on Danny's 756HP 434SBC

in the 1996 Beretta
Danny used a new A-1 Converter 6200 Stall
instead of the 4400 NOS Converter out of the Blazer

_____________________________


here's info on another pair of Dart Pro-1's
on a 432cid SBC made 726.0 Peak HP 566.4 Peak TQ
JE + 3 CC Domes 12.2:1 CompRatio
ProSystems Carb
Edelbrock# 2925

1987 Camaro 2900 Lbs w/Driver

9.17 ET at 147 MPH

will have ET Slip and more Info from Customer Friday afternoon


these are the mostly the older style Dart castings,
not the newer Platnium Series

either the old or the Platnium Dart Pro-1's have a great Port shape
potential to make 700+ HP
on an all out effort i don't see why you couldn't get
770+ HP out of those Heads
at 434cid or under ..even more with larger CID engine

larry

thanks again for the info. In the pic, what intake is used? is it the Edelbrock 4500 super vic, 2970 i think ?

Are you able to get the required area through the pushrod pinch with the dart casting or do you weld/epoxy?

Any issues hitting water under the ssr? I heard the darts can get thin when the ssr is shaped correctly.

Fatman wrote:larry

thanks again for the info. In the pic, what intake is used? is it the Edelbrock 4500 super vic, 2970 i think ?

Are you able to get the required area through the pushrod pinch with the dart casting or do you weld/epoxy?

Any issues hitting water under the ssr? I heard the darts can get thin when the ssr is shaped correctly.

Are you able to get the required area through the pushrod pinch with the dart casting or do you weld/epoxy?

i made a few Tools to checkout Pushrod wall thickness as i Port
so i don't break thru.... i don't need to use Epoxy or welding there.

i maxout the pushrod area as much as possible without welding or epoxy

same with porting the Short Turn Curve,
the Dart Pro-1's have very large deck openings
that you can go in there and measure how thick it is while trying to max
that area out... i have 1 Tool set at .080"

________________________________________

In the pic, what intake is used? is it the Edelbrock 4500 super vic, 2970 i think ?

yes, it should be a 2970
i need to write more Notes when i Dyno


basically the #2925 or the #2970 are pretty close in HP once they
are both highly modified

i take the #2925 along with Moroso #65000 Dominator adapter
and turn it into a #2970 on the Runner Dividers

and i'll take out the #2970 further by milling out the Plenum area
and clover-leaf for hi RPM HP on a good pair of Heads

Pics

Larry

With regards to the 4500 flange of the 2970, why not leave the cloverleaf shape at the face but then blend it out as you radius into the tops of the intake runners?

I thought the cloverleaf would take up some dead space in the plenum, maybe making it more suitable for a 700-750hp small block.

My question is why not start with the 2970?
It looks like the runners are straighter (coming into the head),
and the csa is 3.2" on the 2970 compared to 2.8" on the 2925 (per edelbrock)
Also looks like the 2970 would need less work in the plenum.

Would it be a bad idea to run the 2970 (less porting for me) with a 4150 carb, on a 600+hp 420sbc?