Don Terrill’s Speed-Talk

Have a pair of EQ heads hybrid vortec heads , 194/150 valves, has traditional intake ports(not tall Vortec type) and according to them it’s 240 cfm at .550. They say they are an air speed head, does respond well with light work but they've had the best success with the 1.94 valve. What port, and bowl work would you recommend?

3/8 dirt track on 9.5” wide tire tread
780 cam Holley mech secondary
244/248 @.050"
.352"/.359" lobe Lift
105 LSA
Victor jr 2975 (Would a super Vic make sense on this combo?)
3.48 stroke 45 lbs crank Honda rod journal size
370gm pistons on 6.125 rods low tension rings
Possible 1 5/8 header with open exhaust

What size bore are you using (cubic inches)? What kind of power and top rpms are you setting on the track? What is the cc on the intake port? Is this an iron head rule book spec. engine?

Newold1 wrote: ↑Fri Dec 07, 2018 7:33 pm What size bore are you using (cubic inches)? What kind of power and top rpms are you setting on the track? What is the cc on the intake port? Is this an iron head rule book spec. engine?

Most of the classes that run that head require a 350 stock block usually no more than .060 over

Newold1 wrote: ↑Fri Dec 07, 2018 7:33 pm What size bore are you using (cubic inches)? What kind of power and top rpms are you setting on the track? What is the cc on the intake port? Is this an iron head rule book spec. engine?

4.030x3.480 355cid
9.85:1 compression max
3500-7000 range
They say out of box is 176cc runners
Cast iron head rules,23 degree valve angle

Spend time to work with the Header collector length to get the best average power in a 3200 to 6800 rpm range .

My limited iron head rules knowledge tells me those heads probably only flow about 220-225cfm at .500 and they start to choke cfm at +.500" lift.

Most iron head experts like Brzezinsky will probably confirm that.

I think this set of heads even with this profile camshaft will choke on power and rpms at about 6200-6300 rpms.

A cam with more lift probably won't help overcome the rpm choke and an increase in duration will help slightly.

I think if you really want to pull hard to 7000rpms you are going to need more head on the intake side and a better camshaft design. JMO

With your iron head class rules I don't know what you are limited to with respect to camshaft lift and duration if any but there are obviously a lot of camshaft builders who have dealt with this type of iron head class rules and know how to maximise what your set of heads can produce with the best spec.

I think it becomes obvious why the iron head rule short track racers who win a lot with their engine builds really use a lot of special selection and tweaking to get to the trophy wins.

I have made a couple of sets 2.055/1.60. With Porting they were badass. 520hp 355 dual plane flat tappet cam 650cfm carb. Circle track engine.

Not sure what iron head rules the OP is racing under but a lot of these rules restrict porting and major changes to stock like valve size specs and such?

The OP needs to let us know what the restrictions are on his iron heads as he already has purchased them and has them in his possession.

i also have a pair of EQ heads hybrid vortec heads sitting on my Shop floor

ran only 1 Mud Truck season and won the yearly local Championship
2.055/1.600 Valve no Porting, not even Port matching allowed
just any creative Valve Job only with Cutters allowed , no blending ridges left by Cutters
had to pull 14" inches Plenum vacuum Rule, + 750 CFM stock Holley Rule,
Hydraulic Flat Tappet Lifter Rule + Dual-Plane
362cid SBC = 500 HP at 6200-6400 RPM

the Customer let his Machine Shop Buddy do refreshen-up Valve Job
and plunged cut a deep 75deg Blade on both Intake and Exhaust sides
killing all the Flow numbers, razor sharp bridge between Intake and Exhaust Bowls
its a miracle there's no breakthru to the waterjacket in that area,
the Machinist totally ruined the Heads

i'd give them away , just for the UPS freight charges ( No guarantees of any kind on these Heads )
and i'm postive they will easily get a crack right across the Intake/Exhaust bridge
and they are paper thin next to waterjackets .

We replaced those Heads with a new pair of ProMaxx Vortec Heads
and made 525.9 to 526.0 Peak HP and won 2 more Championships

maxracesoftware wrote: ↑Sat Dec 08, 2018 1:24 pm i also have a pair of EQ heads hybrid vortec heads sitting on my Shop floor

ran only 1 Mud Truck season and won the yearly local Championship
2.055/1.600 Valve no Porting, not even Port matching allowed
just any creative Valve Job only with Cutters allowed , no blending ridges left by Cutters
had to pull 14" inches Plenum vacuum Rule, + 750 CFM stock Holley Rule,
Hydraulic Flat Tappet Lifter Rule + Dual-Plane
362cid SBC = 500 HP at 6200-6400 RPM

the Customer let his Machine Shop Buddy do refreshen-up Valve Job
and plunged cut a deep 75deg Blade on both Intake and Exhaust sides
killing all the Flow numbers, razor sharp bridge between Intake and Exhaust Bowls
its a miracle there's no breakthru to the waterjacket in that area,
the Machinist totally ruined the Heads

i'd give them away , just for the UPS freight charges ( No guarantees of any kind on these Heads )
and i'm postive they will easily get a crack right across the Intake/Exhaust bridge
and they are paper thin next to waterjackets .

We replaced those Heads with a new pair of ProMaxx Vortec Heads
and made 525.9 to 526.0 Peak HP and won 2 more Championships

Yea, but it was "My Buddy" ... you know; that person who just knows about EVERYTHING.

by Walter R. Malik
Yea, but it was "My Buddy" ... you know; that person who just knows about EVERYTHING.

i would need to look at them again to be very sure ,
but it could be even an 80degree or 85 degree large deep bottom cut .

and one thing i'm certain is that large blade bottom cut is right under the 45deg Seat angle
no other bottom cuts like a 60deg on either Intake or Exhaust sides

just straight off the 45deg seat with that Bowl-Hog or Blade

Maxracesoftware

On those EQ heads before your "buddy" worked his "magic" on them what rpms would they pull to on the high end?

Newold1 wrote: ↑Sat Dec 08, 2018 4:40 pm Maxracesoftware

On those EQ heads before your "buddy" worked his "magic" on them what rpms would they pull to on the high end?

i just looked at all the Pictures plus the Dyno Sheets
we made 501.0 Peak with #062 Vortecs 2.055/1.600
and 499.9 to 500.0 with EQ Vortecs 2.055/1.600
and 525.9 and 526.0 with ProMaxx Vortecs 2.055/1.600

basically all times Engine's Peak HP RPM were between 6200 to as high as 6500 RPM
no matter which Heads were on the Shortblock

i'll create a separate Thread with Dyno Sheets + a bunch of Pictures + Flow Numbers
of #062 Vortec , ProMaxx Heads , EQ Heads

originally started out with out-the-box #062 Vortecs and aluminum GM Dual-Plane
SBC Mud Truck Engine
GM Chevy OEM cast iron Vortec Heads
Edelbrock GMPP Vortec Air Gap dual-plane
Original 461 short block with Cam Motion Hyd Flat Tappet
1.52 Rockers
33 btdc
.035 valve lash
Rhodes Lifters VMax
12.4 CR
VP C45 .729 SPG Oxygenated Race Fuel
Vaccum Pump
------------------------
90/92 from 86/86 jets
raise float levels
93.5/96 from 90/92
.018 from .035 valve lash across hot

made : Peak HP all over the place .... Note: this is from one single Dyno test run
426.1 @ 5200 RPM
426.4 at 5400 RPM
426.7 at 6000 RPM
426.4 at 6200 RPM
some of that is results of Rhoades Bleed-off Hydraulic Lifters


next series of Dyno tests were those very same #062 Vortecs maxed-out only with custom modified Goodson 3d Cutter Bodies/Cutters
and with a 6-Angle Valve Job, along with more Engine Mods, etc.
made 501.0 Peak HP from 426.7 Peak HP

PS: as a side Note :
we Dyno tested + Flow tested a pair of Illegally Bowl Ported #062 Vortecs 2.055/1.600 by Head Porter up north
and it made best of 489 Peak HP illegally ported

this was our 1st effort
to see if the Customer's Son would like racing a Mud Truck ??

he went from finishing almost last place with this Engine
to winning 3 Championships as we built better Engines/Cyl Head/Cam combos
and also as he became a better Driver !

i'll start a separate Thread as soon as i can with more Info on Vortec Heads

made : Peak HP all over the place .... Note: this is from one single Dyno test run
426.1 @ 5200 RPM
426.4 at 5400 RPM
426.7 at 6000 RPM
426.4 at 6200 RPM
some of that is results of Rhoades Bleed-off Hydraulic Lifters

Sorry I had omitted to post other rules. 9.85:1 comp max,360 max cid .540/.560 lift rule solid cam and lifters(stock diameter,no mushroom type face), 7000 rpm pill. Any header, any muffler(most use inserts at the end of exhaust tubes to be legal lol. Any intake,Intake rule is max 7” from block top to carb surface. I was told by EQ rep that HVH had done testing with them and best result was with the 1.94/1.50 valves(not sure if this was specific to a certain sanction rule) but with what I assume was light work and specific valve job. I’m not one to hack away on ports etc, just want to match as close to what I can with the rules. The reason I got these heads was because of a sponsorship deal, so can’t complain about that. I realize horsepower wise they might not be the most perfect but with my recent experience with to big of a head I know I’d prefer a good strong torque curve more than hp numbers. The cam numbers I got from Mike Jones based on what I currently have engine wise and these heads. Porting is allowed. Have been using 93 non ethanol pump gas.
Might also add that my previous top end was the large runner Vortec bowtie heads/ bow tie raised runner intake, with a 252/255 @.050 duration and required a lot of gearing and still wasn’t strong lower on the track. Most run a 6.20-6.33, I had a 7.00. Tire sizes being near the same and car handles good so not a chassis/handling issue. 3000 lbs car.