A new BBC Gen 7 electronic EFI BBC project

[Newold1]

I have been working on a new BBC creation of mine and I thought some might get some enjoyment out of a first peek at a "New-Old One"

I am posting a few pictures that kind of point out some of the interesting and unique aspects of this engine and my fabrication ideas.
I call this thing my "588E" which stands for a 588 cubic inch all electronic EFI big block chevy engine. It has some pretty unique and special parts as you can see from my lousy photos, Ha!
I will give a quick outline of the basics. This is a normally aspirated ,pump gas engine, computer controlled and destined for a special street truck.
It started with a tall deck bow tie CNC race block with a Crower 4.5" stroke cranshaft, Oliver 6.535 rods, Wiseco Pro-Tru 4.560" dished forged pistons, Total Seal gapless rings.
The heads are very unique in they were a brand new set of GM 10051128 late 1988 vintage pair of symetrical port heads that have been modified a bit for better intake port shape and are set up with a very nice Jesel shaft rocker setup. Valves are custom 2.35" intake and a 1.85" exhaust. The heads flow 440I/335E at .750 lift. and have an 84cc combustion chamber for a final 10.75 to 1 comp. ratio
The camshaft is a billet solid roller "zero lash" with 264/272 duration @.050, .750 lift at the valve and a 116 degree LSA for the IR EFI setup, with a new LS firing order-18726543.
The roller lifters are Crower super duty .150 offset intake, centered exhaust with roller bushings and high pressure oiling.
The special intake is my fabrication and it is an EFI Individual runner type with 4 viper 68mm throttle bodies inked together to supply the air. The injectors will be 80lb Siemens Deka stubby injectors.
The ECM will be a Holley Dominator system and should from what I have learned make tuning easier with dual wide band O2 sensors.
The intake manifold and a lot of the engine was calculated and designed with help of PIPEMAX and I am planning on between 825-875 HP @ 7000rpms about 800 lb/ft. of torque @ 5600 rpms.

Getting close to completion now with just some manifold welding and finishing the engine wire harness. Hope for a nice finish! There's no replacement for displacement in my mind when it comes to N/A!

Hope this build will stir others to build "something special"!

[In-Tech]

Very nice, just a tip, I had problems with that GM v-6 crank sensor and had to mod my cover to use a different GM sensor to get a better signal. And remember to get a 7" Balancer as an 8" will hit the Cam sensor

[Newold1]

Rays 588E-1 006.JPG

valley plate.JPG

Injector placement.JPG

24X timing setup.JPG

Carl, thanks for the complement and tip!.
This project has been a bit of a "MacGiver" type challenge. But I am kind of driven by the adage "If it was easy, anybody could do it"
By using a Gen 7 BBC 6 bolt timing cover with the provisions for both a bottom mounted crankshaft sensor that reads off the reluctor on the crank snout and the front mount camshaft sensor that reads the upper camshaft gear, it manages to nicely clear my 8" ATI super damper. You can see the pieces in these attached pics as well as how the front timing cover mounting requires adding two additional 1/4" -20 drilled and taped holes in the block face to mount the new Gen 7 cover. This also then creates another issue in that the oil pan must now have a Gen 4 rear seal lip and a Gen 6 front lip to seal a similarly morphed silicone pan gasket. Lucky for me Bill at Canton has modified a few oil pans for this setup and it all goes together very nicely.
The injector placement in my fabricated IR manifold with the limited height and need for a good aiming direction was only possible with the Siemens Deka stubby short injector. Guess I would rather be lucky than good! I had fun making a removable valley plate for the intake but it will make cam changes a lot easier. Just like a LS engine!
Hell, what am I saying, THIS IS JUST FUN!
Some more pics attached.
I am now sort of thinking with the evenly spaced symmetrical intake ports of the heads, the new LS firing order and the coil on plug ignition less a normal distributor that one could think of this engine as a 588 inch big block LS engine. To bad GM never got this far with the big block, although they do have a new 8.0L crate big block from GM Performance that uses this system on a nice block with forged internals, but they fell short a put on old set of iron peanut port heads on the offering and really limited its potential as sold in the catalogue with no block only for sale.

[Cutlassefi]

Cool build, but 80# inj are too big for 875hp NA. You should use 60's at 60psi. Always use the smallest inj possible at the highest pressure, it'll drive better if in fact you're going to drive it.
Any plenum under those throttle bodies? It would be better if there weren't and they were just tied together for a vacuum signal.
Don't really need the dual widebands either but if that's the way you're headed then so be it. Neat project though, best of luck.

[Newold1]

Cutlassefi
Thanks for the suggestions, thoughts and compliments. Yes, after some more input I think you are right about the injector sizing. I am going to use the 60lb. injectors, same Siemens Deka and run the fuel pressure at about 50psi instead of the normal 43psi. Some fuel injection experts I talked with say I should be able to still keep duty cycles under 80% and better control idle and part throttle transitions.

The intake is a true IR type 2-3/4" intake tubes with no plenum and just above the fuel rails on both sides of the throttle body plate are two square tubes that run along the length of the base plate and each intake tube has a drilled passage opening into these two tubes. At the back of the throttle body plate the two tubes are connected to a center flange where the MAP sensor plugs in and there is a GM type Idle air motor (IAC) that also mounts to this side of the system to help handle idle, deceleration and quick throttle closure idle stumble issues. I will be running the dual wide band O2 sensors, one on each bank as the part throttle manners and cruise rpms are the most difficult to control on a big cube high HP engine like this when street driven as this one will be much of the time.

It's nice to have the engine management that's available with an electronically controlled EFI engine with a system like Holley's Dominator system I am using. I am hoping I can get this guy to idle around 650-700rpms with air fuels in the 13.5 to 14.0 to 1 ratios and still have 11.5-12.0 air fuels when the beast is unchained! Tall order, but I like a challenge. Gonna take a little dyno time to dial in settings and calibration but I am told this Holley system helps with this tuning a lot.

[Cutlassefi]

Ok, but make sure your MAP and IAC aren't pulling from the same port.
And with a true IR system, balance is more important than anything. If you bought the Holley Dominator just because it has dual widebands then you wasted your money. Don't need them, individual cyl trim is way more important.
I just did a 447 Tall Deck SBC with a Kinsler 8 stack and the AEM Infinity. Runs great. But transient tables and the ability to fuel it accordingly is more important than self learning or any of that hype.
11.5-12.0 will be too fat for wot, more like 12.5:1. But idle will most likely be best around 13.5. This 447 had a 256@.050 solid roller and only 9.7:1 compression, but idled at 800 with the A/C on all day. It's really not the EFI system that effects that, it's the fact that there's no dirty air in the intake, only the area between the valve and the butterfly. That's why they idle so much better than a single plane etc.

Best of luck.

[user-612937456]

I notice you are using a low resolution reluctor wheel. Just wondering with extent you are going with this build why you didn't go with a high resolution wheel for more precise timing in the upper RPM range?

[Newold1]

Cutlassefi:
Thanks again for your ideas and advise. The Map and the IAC both draw from different ports and I understand that if they did not, then a movement of the vacuum signal that would change with the IAC would throw the MAP signal off for that change period. As for the Holley Dominator, I bought the unit at a very low cost from someone who purchased it and ended up not needing it on their project. As for the dual wide band O2's my thought here is that the ability of the O2 to keep the fuel settings and trims in a narrow range for what should be a lot better on the fly tuning. My concern is that I am not a tuner of great experience or ability so I think it will be better to have the strong self tuning features of a system like the Dominator and the widebands should just help in that simplified process. One of the reasons I choose to use these Viper throttle bodies is that each one of the four has a individual throttle plate adjustment screw and I have an airflow device that will allow me to measure each one at idle and set the air flows better in each runner of the IR setup. As for air/fuel ratios, I think your recommendations are good and as for transitions, I need some more education there and I am sure I will get into that once I am into the running and tuning stages. The AEM system you are using is an excellent system and it was one of my final candidates along with BigStuff 3 when I cam to get this Dominator unit at a smok'in price! This project does have a budget and beleive me when I say I am struggling to stay close! Thanks again for you help and good input.

GVX

The reluctor I am using is a 24X as you note is not as fine a resolution as a 50X system, but the 50X reluctor is a much larger diameter and would have required I use a special timing cover and camshaft gear that are only available as a $500 package and I chose for budget reasons to use my $35 dollar reluctor and readily available low cost timing cover and camshaft gear where my system cost was only about $100.
As for the resolution I don't think with the strong coil on plug system and ECM based spark control these coils allow for this package with a 7000rpm max use the added resolution was needed. There seem to be a lot of LS1 engines out there spinning 8000rpms with this 24X resolution. I do appreciate your comment and it was a consideration. Thanks again.

[In-Tech]

Hiya's,
How did this turn out? I would still like to see the front cover with your ATI balancer and cam sensor installed. On the 540 I did, I used a stock appearing(for no reason) 8" damper and had to machine a small groove in the balancer to clear the connector of the cam sensor. Did the holley dominator ecu have any problems with that crank sensor?

How did you like the dominator ecu? I've tuned a couple 1000-1200 whp TT LS's with it and was pretty happy with the results.

[Newold1]

Sorry In-Tech, I just picked up on your post and your questions. The project has been on a hold while I build a new injection manifold system. I actually did not take an important thing into consideration when I put together the original system, manifold and Viper throttle bodies. What i failed to recognize and think about with the LS firing order and the viper throttle bodies was that under loads at 3000 rpms plus on the dyno test was that prior to fabricating that the firing order had 3 cylinders drawing their air flow from a throttle bore that was so close to an adjacent throttle bore with a next in the firing order placement that the air fuel measurements went stupid fat from the fact that the two adjacent throttle bores were trying to pull a lot of air from a very close adjacent throttle bore and both were starved of air and threw the overall operation of the engine into a problem that I first thought was an efi tuning or fuel supply issue. When I finally figured out what was causing the real problem which I could not correct with tuning or fuel supply I felt pretty stupid for not seeing and realizing the problem I had created with my so called "cool" ITB intake system and it's not so "cool" results I had to stop and go to a totally new EFI ITB intake system. I wish someone smarter than me here on Speedtalk had seen my design use error and saved me a lot of time and money, but Oh well it was my error and it bit me on the butt hard!

As I used the Dominator system and was actually trying to tune myself out of the problem I really became a bigger fan of the system. Its an incredible control system and once one gets a little bit of ability in setting up fuel, timing, etc. tables it is really a great tuning tool and engine control system. It would obviously not let me fix on engine the big mistake I made in my original ITB system design, but I now would trust to use it on any performance engine!

As for the clearance on the camshaft sensor to the damper, I never tried using or installing a factory type 8" damper as I began with the ATI 8" damper but in looking at both now I can see that the factory type aftermarket damper I can see that the body of the ATI 8" unit is quite a bit thinner in thickness than the stock type 8" damper so I think that would be the explanation for the need for your modification.
My cam sensor has a right angle connector entrance for the plug and it is a decent distance clear of the ATI damper.

I was so disgusted with my screw-up on the time consuming, expensive bogus build of my original intake system I put the project on hold over the entire fall and winter and I am just now putting together a new ITB system that is using an older symmetrical port 2.9" Kinsler racing manifold that has a workable distance between adjacent end bells to allow my existing LS firing order without the adjacent cylinders "stealing" its neighbors air! I have modified the Kinsler system to move my selected Siemens injectors down from above the throttle plates to new locations below the throttle plates and better aimed at the intake ports. Should be finished in the next few months and I plan to be back on the dyno in early fall for some decent results. I think this engine will make about 950HP @ 7000rpms and about 875lb/ft of torque at about 4700rpms and I hope I can get it down to a 750rpm smooth idle! If I come to these numbers or very close I think I can finally cast off the "shame" of my stupid design error. As I always say, no one knows it all and I am still learning what I don't know ! HA It will be done soon and I am smarter in the process.

[MadBill]

I guess it's a little late to mention, but couldn't you have built splayed/curved ram stacks to fit into the TBs, such that the entries were far enough separated to prevent charge-robbing? Perhaps length-matching the runner length to the desired harmonic/RPM range, say 15"/6,000 RPM/3rd harmonic. (Or even just add a longitudinal vertical divider plate between the L and R TB blades?)

[In-Tech]

I just compared your TC to the one I used and your is different and much better.

http://www.ebay.com/itm/Chevrolet-Perfo ... 0705437458

That's the kit I used, notice the cam sensor bolt, no wonder mine crashed the balancer. It also appears the crank sensor is normal too. Mine used some bs v-6 sensor that gave me fits and I had to modify my cover to take a "normal" crank sensor to finally achieve a stable signal. When you get a chance, for future reference, can you get me the part number of the cover you used? Also, pay no attention to the cam gear in the picture, that is not the one that comes with that kit, the one with the kit is a 4x timing gear. Shoot, now that I think about it, yours is probably off an 8.1

I was going to mention the only thing I did not like about the holley dominator ECU was the lack of individual cylinder trim...meaning it allows you to add or take away each cylinder but it is global, 10% is !0% at all RPM's and KPA. It truly needs to be 3d to be of any value.

Do you have any pics of your new setup or is it still in the thought process?

[zwede]

I was going to mention the only thing I did not like about the holley dominator ECU was the lack of individual cylinder trim...meaning it allows you to add or take away each cylinder but it is global, 10% is !0% at all RPM's and KPA. It truly needs to be 3d to be of any value.

This was true in the early software versions for the Holley EFI. Newer SW versions allow individual cylinder fuel trim based on RPM & MAP. Older ECUs can be flashed with the newer SW and Holley doesn't charge for the SW upgrade.

[In-Tech]

I was going to mention the only thing I did not like about the holley dominator ECU was the lack of individual cylinder trim...meaning it allows you to add or take away each cylinder but it is global, 10% is !0% at all RPM's and KPA. It truly needs to be 3d to be of any value.

This was true in the early software versions for the Holley EFI. Newer SW versions allow individual cylinder fuel trim based on RPM & MAP. Older ECUs can be flashed with the newer SW and Holley doesn't charge for the SW upgrade.

Awesome, good to know. Is the resolution user definable or static? If so can you post a pic of the x,y,z table or allowable size if user defined? Thank you.

[Newold1]

In-Tech, my Dominator Holley ECM has very nice individual cylinder fuel trim and that was what I spent way to much time on the dyno trying to even out the cylinders when I finally realized fuel trim would not work as when I trimmed fuel in the cylinders where the throttles were robbing charge from the other in body throttle it would not hold or be controllable at any higher rpm point and I still ended up with such different cylinder trims I knew at that point that something else was going on!

I am just about finished with the Kinsler modified system and I will post some pictures of that in a few days for interested Speedtalk contributors.

I am using a different timing cover than the one you posted that is for the 58X reluctor as the one I used is for a 24X smaller diameter reluctor. I will post a picture of that cover, cam sensor and reluctor as well as a source for them for you.

Bill, thanks for a good description of what I was suffering from "CHARGE ROBBING"! This is something all builders and fabricators should take care to identify this possible issue developing based on the engines firing order and the ITB fabrication with respect to throttle entrance adjacency. It does really affect things and it can be hard sometimes to identify just based on power and torque results. The individual EGT's and A/F meausrements on the dyno wer the only way I was able to start to see and identify "What's wrong with my damn beautiful engine"!!

I am sizing the length of the new system and it will be a 14.5" long intake tract, end bell to valve.