My 400 SBC VORTECPRO Build

[cage2592]

Jan 2020 I talked with Mark Jones, AKA VORTECPRO to build a 406ci to replace my aging 406 that wiped a lobe with a COMPCAM. This is the build.


VORTECPRO:
Build a mild 406 for a 70 Chevelle, I thought I would post some pictures. I had a very nice thick 817 production block, bore and stroke 4.155 X 3.750, with a 7/16 6 inch rod and a Mahle piston, we ended up with 10.3 compression. The cam is hyd roller, 234/238 @ .050 .560/.530 lift on a 110. We used a AFR 195 head with modifications and a performer RPM air gap intake with a 1 inch open spacer. Carb is a AED 750 CFM. We plan on testing different distributers, locked and with a timing curve. Gas will be 91 octane from 7-11. Should be a interesting build. I should mention the valve job from AFR was a disaster. Run out on the center ex seats, has to sink .010 too fix. Hand Porting resulted in 275 CFM @ .500 lift @ 28 inches 4.155 bore SF 600.

Balance sheet ? 1728 grams
All ARP ? Yes
4 bolt mains added ? No GM 2 bolt
Pistons ? Mahle
Crank ? Scat Remachined
Rods ? Scat. Remachined
VE 101.9

 

[cage2592]

As Mark finished dyno runs. I think this will surprise some. He's put a lot of time and own custom touches into this build and its been highly educational for me as well. Those that have talked to him know he's a perfectionist. I cant thank him enough for taking this build on.

Current setup:
CPP full Pro-Tour kit
Viking coilovers all around
dropped 2" Front / 3" rear (2" rake)
18x8 front / 20x10 (28" tall) Rear AR Torq Thrust II's
TH350 w/Vigilante 2800 Converter.
3" stainless exhaust (no X or H) through Dynomax Ultras (turn downs before rear).
Gear selection is still considering.

This is a daily with power brakes and A/C, with a request that its street-able for PB, AC and 500+hp.


Some may have read that my old 406 wiped the #5 INT lobe and I was originally going to upgrade to a roller. By the time I ran the numbers on a roller change from FT and AFR's, It made sense for a rework. By then I was into a new build cost. Thought about a Crate and looked at all of them but didnt find one worth much. So I called Mark.

Old 406 Engine:
750 Holley DP
Edel Perf RPM (Non Air-Gap).
Moroso 1" Carb Spacer.
Eagle Street/Strip balanced rotating Assembly (ESP-13008030).
Cast 3.75 crank.
Forged I-Beam 6" Rods.
KB Hypereutectic Pistons (9.6:1 Comp).
Sportsman S/R Iron Heads
CC XE274H FT (230 INT/236 EXH, .490/.490 (@ .050) w/12"vac.
Harlan Sharp 1.6 rockers (Brings lift to .525)
Timing 36* all in by 2800rpm.

 

[cage2592]

35.5 total timing

 

[cage2592]

 

[bikeron]

Nice.. why run so rich? Curious as to what torque is at 2000 RPM..

 

[cage2592]

VORTECPRO:
I used my locked MSD ready to run dist first, then changed to the customers MSD street fire with mech advance, very little difference between the two. Not sure about the dip, probably from testing at such a low RPM, when tested from 4000-6100 no dip.

 

[cage2592]

VORTECPRO:
The cam was made to my specification by Spirro Jennings @ Redline on his Landis CNC cam grinder, a master grinder I might add, on a steel core with a cast gear. 234/238/110.

 

[cage2592]

I thought hard about asking Mark for this SB. My dilemma was a 550HP SB (I asked for 500+) or his 650HP 496ci. What swayed me first toward the SB was Marks quick availability of a 400. He's rightly so, picky about his cores and good 400s are getting harder to find. Had Mark said there was going to be an issue finding one and or driving up the cost significantly of a DART block, I would have went 496. Second was the fact that the car was already set up for a SB. Front springs were already matched to the weight and handling and the car is as low as it can be without avoiding certain roads for hazards. Third was all my parts I'm reusing, A/C, PS Brackets, water pump, etc... was all small block. Yes it cost me more but by the time you figure in collecting BB parts and suspension I would have been at the same price or more. Even going with a lower HP BB. Which if I was upgrading, why go low? Lastly, this SB HP/TQ/Weight ratios is outstanding and Mark delivered !

It’s my opinion that Mark made the best SB street combination that you’ll find for a fully dressed street car with accessories. It’s the details Mark contributes that make this motor and all parts compliment to get those numbers.

My old 406 fit under the hood with a 1" open spacer this AED 750, flat bottom air filter base and 3" tall K&N.

I'm thinking of trying a "Blow-through" Style carb hat with 4" silicone smooth tube that goes to an air scoop under the bumper and mounted in the air dam.

One thing at a time though.

 

[cage2592]

VORTECPRO:
I think if you take my 467 and put Mahle pistons in there with the same cam specs and a 781 head you can be looking at 650 HP/600TQ with some detail work. So lets look at the numbers, we will use my NHRA stock Buick for a comparison.

Buick run @ 3500 pounds 8000 DA 4800 feet elevation 11.45 @ 114 MPH 24.70 baro
370 observed dyno HP @ 6400 feet elevation 23.70 baro
512 corrected HP/558 TQ

406 small block dyno
394-401 observed dyno HP @ 6400 feet elevation, 23.31 baro
555 corrected HP/540 TQ

So the 406 in the Buick considering it would weigh 3350 and makes 20 observed HP more, carries the power much better, means at least 11.20s in my Buick, but thats at 8000 DA, so your probably looking at 10.60 in low altitude, but thats with a 800 RPM idle

Might have to try that test....hmmmm Buick 406 dyno / drag test?

 

[cage2592]

I'll be setting it all up on the engine stand to check the alignments, install brackets and accessories. Plus I’m going to bolt a spare TH350 to it while on the hoist and fit the headers. I’ve had headers hit the Trans converter/flywheel cover mounting lip before due to changes in heads. May have to shave the lip down some.

It currently has a disc/drum but after this engine is installed, the Quick Performance rear is going in with disk. Reason for not changing the rear first was to install the engine and see how the car drove with current gear in town and HWY and help decide which gear to go with. I don’t mind the Gearing Calculators but I want to see how it reacts to the converter as well.

 

[bikeron]

Why a carb and not FI?

 

[kmakar]

If it's a daily, why not go FI?

 

[cage2592]

VORTECPRO:
What I charge to set up a Dart SHP

200.00 Block prep
350.00 to bore and hone with plate
275.00 to line hone, if it needs it

For whats it worth I charged the customer 300.00 for my very thick sonic checked 817 block. Usually when some one needs block work done I send them to CNC Carl, I knew Carl would have a field day with my production 400 block build

 

[cage2592]

Few issues I had during mockup was even though my Power Master (PM) Starter is very small compared to the production size, it was hitting the inside 1 ¾ exhaust tube and had to be dimpled. The next real issue I had and was unprepared for was the starter pinion hitting the flywheel. I already had installed the starters set it came with for my previous engine and didn’t have another. Looking on PM’s website didn’t help for a PN# and found an old post about Tilton Starter shims fitting PM’s. Ordered one from Summit and had it overnighted. Didn’t need a top shim. I had to make and powdered some brackets and bushings to mid mount the ALT and align to the crank pulley. When mounting the mech. fuel pump I used a Straub pump rod which was well made. I wanted to weigh it against the Comp Cam lightweight but couldn’t find it.

Finally got the engine installed about 3pm Thursday and everything connected up around 8pm. Before startup I made sure the oil filter was full, drained some oil out of the pan (shipped with oil and filter), poured a qt. over each valve train and installed the valve covers. Checked oil, connected vac. gauge and timing light, disconnected the coil wire and cranked the engine over a few times. Connected the coil, a snort of starter fluid and it started first crank. Immediately it idled at 1300 and with vac. at 17”! Sounded awesome and not a single hesitation or burble. Oil pressure at 70psi. Brought idle down to 1000 with vacuum coming in at 15”. After warmup (170*) checked timing to ensure 35* which came in at around 2700rpm with no change on up. Re-verified vac. at 1000rpm, turned on A/C (w/condenser Elec. pusher fan), all electrical and large Elec. SPAL fan. Idle dropped to 920rpm and 14” of vac. Put in gear and idle went down to 760rpm and 13” vac. . Reset carb to 830rpm and the engine idled super smooth and holds a steady 13.6” (+/- a tenth).

Went for a low RPM 4 mile country road test drive (open headers) stopping slow brake pressure and holding brakes with all great. Got it home into the shop and still 170* engine temp.

Friday morning got up early and drove it the 28mi. country roads to a friend’s muffler/brake shop in town. to bend and weld the 3” Stainless exhaust through the Dynomax Ulta’s. We were all surprised that this engine was actually quieter than the older non-professionally built motor. I would have thought flowing more exhaust and a touch more cam would be louder.

So, at 2pm yesterday (Friday) on a gorgeous day in the smack middle of Tallahassee on the main road about 3/4 a mile from the State Capital I eased out of the muffler shop, hammered the go pedal and laid down about 6oo yds. of dark rubber with a HUGE smile. (Thank you MADMANMARK and BLUE_69_MALIBU) and It was beautiful!

The 28mi. home drive was great holding steady at different RPMs without a hesitation. Every stop the engine idled super smooth. We have a country HWY 4 lane with never any traffic on it so with no others around I got on it at about 40mph taking it to XXX (Blurred for the speed haters). I was amazed at how fast the RPMs climbed then. Like no effort at all.

Got home and not a drop or hint of any leaks. Drove it the 25mi. on I-10 to work this morning. Still all the same.

I still have some small items to do. I threw what long AN -6 fuel lines I had and just connected the vac. Lines. So make up proper length and routing of lines, hoses and wiring. Just running a Fram high flow PCV and need to install and adjust the Wagner PCV.

 

[cage2592]

I'm running a solid driver, poly pass. and poly trans mount. Still the smoothest engine I've ever had or rode with. And I hate squeaks and rattles!

Ill be calling them on Monday though to see about scheduling the dyno. Talking to Mark last night and as you know, this wasn't built to run the 1/4 but I think it should just to get some times and data for everyone. I pretty much had the carb dialed in when I sent it for Mark for the dyno run. I'm running it straight off the dyno settings other than changing from 71 to 75 on the mains. The collectors we welded in both have O2 bungs in both sides and will be installing the gauge and sensors soon. Ill tweak it more then.

Valve covers are Canton Racing 65-201. I like them over others because they were a heavier ga. Alum, solid bolt stems all the way down (not just holes on the top and bottom, a rolled flat bottom and a fill cap with o-ring. Not just a cheap flimsy build. The only thing I didn't like about them are that they don't have a welded internal baffle in the breather holes. I used Moroso breather grommets and opened them up a little more.



Installed a Wagner PCV this weekend to try and see what VAC numbers I could get. I originally bought this a few weeks prior to engine arriving as there was a group buy going on and wanted to have an option in case vacuum was low. My original numbers were from a FRAM FV178. At idle of 850rpm I'm now getting about 15" (from 13"), and 1000rpm about 17" (from 15"). Just wanted to put this out there incase someone is contemplating a cam that's right on the line of VAC with P/B. Like I previously posted, my original numbers are good for my P/B setup, but I wanted to see what the results of the Wagner were.

Nothing else on the motor has changed.

This next weekend is adding a TRANS temp and Wideband 02 gauge.

 

[cage2592]

Nice.. why run so rich? Curious as to what torque is at 2000 RPM..

bikeron,

Not much carb work was done while on the dyno. only changing the primaries to account for the Colorado altitude. Once I got it installed and the 02 sensor, I drove it around here in the country, changing plugs and dialing in the carb. It now idles at 830rpm and 13.4 AFR. Cruise is 13.8-14.2 AFR. WOT is 12.8. we knew it would run better on 93octane at sea level and a better Carb dial-in.

 

[cage2592]

Gents,

It is a daily. I drive it 60mi round trip on the HWY (I-10) on days it doesn't rain. Getting at a min of two days driving a work week. 9 months later and I'm at about 12K miles on it. I have put several FI cars together, with several being this year. Its just not for me. I really like tuning Carbs and have been since I can remember. There is no chance of me changing this out for FI. There isn't a flat spot in it and the throttle response is super crisp. Though we just did a friends Camaro and we did a belt driven mechanical Fuel Pump for his FI and it is amazing. I'm not having any fuel issues but Id love to swap it over.

 

[cage2592]

So this brings us to today.

Changes made in the last few months:
1. Took out the Magner PCV and replaced with an open breather like the driver-side for dual breathers.
2. Rebuilt TH350 Trans with Precision Vigilante 3000 Converter
3. Changed out more CPP parts for UMI and lowered the rear anther 1" for about a 3-4" rear drop.
4. Quick Performance 9" with 3.00 rear gear. Added full UMI ROTO-JOINTs
5. 275 rear, to 295, to now 305 rear tire.
6. Added Idle Stop Solenoid to Carb throttle for AC RPM bump.
7. Different AC compressor bracket.

Whats Next:
1. Still need to finish the outside air scoop fiber glassed in the chin spoiler for the Carb hat and intake pipe.
2. Waiting for the Carbon Fiber Driveshaft from Precision Shaft Technologies in Tampa.

 

[kmakar]

I've decided to go with Edlebrock multi port FI with distributor for the '68 GTO convertible (455 .30 over with TH400) from a standpoint of ease and smooth running on E10.

The Starfire is staying completely original (with the exception of a 3 row aluminum rad and 160 tstat) to keep it cool. Completely bone stock engine is a 394 Ultra high compression 10.5:1.

I'm deep into pulling the front off the motor to replace a seized water pump and I figured if I was that far into it, I might as well replace the timing chain and gears (some models came with a nylon gear), since I had to replace the timing cover (snapped bolts when I was pulling the water pump and it was very pitted from it sitting for so many years).

 

[cage2592]

Multi Port is definitely the way to go if going in that deep.

I always like the 'While I'm in there I might as well..."

Its gonna be a sweet ride for sure !