Holley Avenger EFI on Budget 532 lbs-ft 383

[David Vizard]

While this build is not a really low buck build it is a budget orientated long block assembly with a Holley Avenger self-learning EFI on it.
The money saved on the long block went some way toward leveling the difference in the cost of a carb versus the EFI.
My point for posting this is that I have been getting some good results with the Avenger EFI system – but I have only used it on four builds. What I want to know is whether or not these results are representative of other builds being done out there.

Here is the low down on the engine:-

Scat 9000 cast steel crank and Scat pro series I beam rods, 10.5/ Icon pistons, Rotating assembly internally balanced. Damper from PRW.
Block machining and crank balancing and dyno testing at Terry Walters engines in Roanoke.
This build was a joint project between Terry Walters Jack Sain and I. Thanks guys for the help.

Cam was a Comp single pattern Hyd QXI roller series 285/233 delivering a measured 0.630 lift with high ratio Scorpion rockers. Incidentally my 128 LCA formula, when applied to this engine, came out at 106.7 degrees and the cam, computed on COS-Cam, was ground on a 107 LCA. Note the big torque/cube numbers and the fact that at peak torque it closely approached the 1.4 mark and this was all done with very basic parts. So once again for the record if you don’t like/agree with the 128 formula for a SBC don’t use it. BTW the cam was power timed in. Cannot remember where it ended up for best output.

Heads were a Chinese casting that Terry has found is an OK casting but not so good on the machining so he gets a semi-finished casting and does the final precision work. When there are so many well-made and functional US made heads I am not in a tearing rush to promote off-shore made stuff. But the price was right and allowed the use of a Holley EFI which from the results I have so far seen I do want to promote. These heads have a 200 cc intake port that flows 260 cfm out of the box. Not so good is the exhaust port which, as cast, is only about 160 CFM. That is a little short of what is needed if the intake is fully utilized so for this engine I did a quick and simple porting job on just the exhaust. This proved pretty effective for the minimal time involved. Flow went up almost everywhere with the number at 0.700 being right on 190. I think I spent something like 10 mins per runner here. But all that said Terry has mentioned he is hoping to get a deal with Edelbrock for E-street heads at almost the same price and we know from dyno testing these many times that results they deliver are good.

The intake manifold was an Edelbrock Performer airgap and the reason I use so many of these is that they always give good numbers on the dyno. For this combination Terry found that a ‘super sucker’ 4 hole blended 2 inch spacer was always worth extra output with the Holley Avenger system on bigger engines (350 on up).

This engine was first broken in on a 950 Ultra Holly carb that was already calibrated for a similar engine. Once broken in the carb was jetted to give best results. The AF ratios were noted and the Holley system which is self-calibrating was installed. At first the engine was down on the carb by about 15 numbers but as it learned the difference slowly became less. We could not wait for the amount of running required for the system to fully set itself up so we calibrated it to replicate the AF numbers seen with the carb and as such it ran within about 4-5 numbers.

So that was the engine but as I said my focus here is the Holley EFI. What I would like is to hear from other users how this system has fared in their hands as I don’t believe I can give an all-around opinion just from four builds. With RPM as x 100 here are the numbers:-

RPM - TQ -- - HP -- Tq/Cube
30 - 494.0 - 282.2 - 1.29
31 - 497.2 - 293.5 - 1.298
32 - 499.1 - 304.1 - 1.303
33 - 503.5 - 316.4 - 1.315
34 - 503.2 - 325.8 -. 314
35 - 502.6 - 334.9 - 1.312
36 - 502.9 - 344.7 - 1.313
37 - 507.5 - 357.5 - 1.325
38 - 509.1 - 368.4 - 1.329
39 - 512.7 - 380.7 - 1.339
40 - 515.7 - 392.8 - 1.346
41 - 518.6 - 404.8 - 1.354
42 - 517.1 - 413.5 - 1.35
43 - 519.7 - 425.5 - 1.357
44 - 525.1 - 439.9 - 1.371
45 - 528.2 - 452.6 - 1.379
46 - 531.1 - 465.2 - 1.387
47 - 532.8 - 476.8 - 1.391
48 - 532.1 - 486.3 - 1.389
49 - 531.4 - 495.8 - 1.387
50 - 529.2 - 503.8 - 1.382
51 - 527.2 - 511.9 - 1.377
52 - 524.9 - 519.7 - 1.37
53 - 520.6 - 525.4 - 1.359
54 - 515.6 - 530.1 - 1.346
55 - 510.2 - 534.3 - 1.332
56 - 504.2 - 537.6 - 1.316
57 - 498.0 - 540.5 - 1.295
58 - 490.7 - 541.9 - 1.281
59 - 479.8 - 539.0 - 1.253
60 - 471.5 - 538.7 - 1.231
61 - 462.6 - 537.3 - 1.208
62 - 454.0 - 535.9 - 1.185
63 - 443.1 - 531.5- 1.157



DV

[Wolfplace]

Torquey little devil
Nothing about the tune in general except what I normally do with anything that has much overlap where it is obviously rich when the lambda says otherwise is shut learning off a few hundred RPM above idle & manually tune the AFR below that. Just grab about 9 points around your idle & lean them til the RPM drops like you would do with a carb difference being instead of a screwdriver.. while kicked back in your easy chair........ you use the up/down keys
Reason is with much overlap the O2 sensor will read lean when it isn't & keep adding fuel.
Can also happen with the sensor too close to the exhaust opening

[David Vizard]

Mike,

Thanks for that piece of info. I well be sure to apply that to the next self learning EFI I do.
See you at PRI maybe??
DV

[Wolfplace]

Mike,

Thanks for that piece of info. I well be sure to apply that to the next self learning EFI I do.
See you at PRI maybe??
DV

Yes sir you will, Darlene & I will be there as long as the big bird can find it's way
When you coming to visit the pack? They are outside the window howling as I type

[David Vizard]

Mike,
I would love to visit tomorrow but these health issues are just pulling me down to the point my energy level is bottoming out.
But as soon as the opportunity presents itself -------!
DV

[BigBro74]

David and Mike - l love when you guys post. always learn lots!

David - I always try to reverse engineer what you are doing to help my own knowledge and sims etc- so two questions 1.7 rocker? and 72ish overlap or so?

Mike - I always like to hear the solutions guys like u come up with- simple and effective!

Jason

[David Vizard]

David and Mike - l love when you guys post. always learn lots!

David - I always try to reverse engineer what you are doing to help my own knowledge and sims etc- so two questions 1.7 rocker? and 72ish overlap or so?

Mike - I always like to hear the solutions guys like u come up with- simple and effective!

Jason

Jason - The rockers were 1.6/1 but actually delivered 1.61/1 and the overlap was actually 71 degrees. For what it is worth i have had some good results every time i have used Comps hyd. QXI profiles (page 20 of Comps profile catalog.)

DV

[Casper393W]

Dang,

I come and join this forum and who do I run into...David Vizard. This is Andy Wood, I hope all is well your way.
Did you ever finish that SBF book? I now have a 1971 F100 that im building into a gasser style build. Its going to be powered by a 393W. I'm giving a tunnel ram a try on this, should be interesting.

Andy

[David Vizard]

Andy,

Heard life was dealing you some not so nice issues to take care of. Hope all is well on that front. Still working on the SBF book. Wanna drop by and see what i am doing??
Take care.
DV

[David Vizard]

Andy,

Heard life was dealing you some not so nice issues to take care of. Hope all is well on that front. Still working on the SBF book. Wanna drop by and see what i am doing??
Take care.
DV

[77cruiser]

Nice build there David, makes about the same as my 421.
What does it have for idle vacuum at what rpm?

[Casper393W]

life has a way of throwing curves...God has seen me through it! Im building a mismatch of parts.... 393W 11.4 to 1 compression, Ford Racing GT40X heads (I know they aren't that great but its what I have) Im thinking of a cam with around 240 deg. @ .050 with a 106 LSA because the heads only have 1.94 intake valves... With .550ish lift. Im going old school with a Weiand Tunnel Ram with Holley 1850's modified having Annular Boosters. I think it should be good for 475hp on a good day... I will try to get over to see you maybe this week.

Andy

[David Vizard]

life has a way of throwing curves...God has seen me through it! Im building a mismatch of parts.... 393W 11.4 to 1 compression, Ford Racing GT40X heads (I know they aren't that great but its what I have) Im thinking of a cam with around 240 deg. @ .050 with a 106 LSA because the heads only have 1.94 intake valves... With .550ish lift. Im going old school with a Weiand Tunnel Ram with Holley 1850's modified having Annular Boosters. I think it should be good for 475hp on a good day... I will try to get over to see you maybe this week.

Andy

Andy,
Look forward to it. May have something to save the day for you - (note the 'may'!)

DV

[JoePorting]

Those are good power numbers considering the heads. I'd think you can pick up close to 100 hp with some AFR 210 heads.

[David Vizard]

Those are good power numbers considering the heads. I'd think you can pick up close to 100 hp with some AFR 210 heads.

Yes Joe I am sure we would have picked up a bunch of power with AFR heads but I am not sure about 100 hp gain but who knows unless we put it on the dyno. The point of this test is that we saved a bunch of money on the heads so that was part of the strategy to help cover the cost of the EFI. But really as this is a street motor the torque curve - especially low down was the prime factor. This build was a true street driver and pulls strong from a little more than idle.542 hp from a real street driver on 87 octane fuel sounds like a decent number.

DV