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As the title says, I'm looking for advice when going from the Holley Stealth Ram to a single plane. I looked through the single plane thread but it's been a long time and a lot of other intakes/throttle bodies are available now and I know lots of you folks have installed a single plane EFI intake by now.
My goal is better air/fuel distribution. Picking up some power would be great too. I am also using nitrous with a single nozzle in front of the throttle body and have wildly different plug readings. I think it's due to the front mount TB and the bosses inside the plenum. I could go direct port but still have distribution issues at part throttle. There are other minor issues like not being able to remove my distributor cap with the plenum in place and I believe a single plane layout would help with those type issues.
I like the looks of the HSR and the filters in front of the radiator. I am OK with a single plane's looks but would still like to retain the air filter setup although it negotiable. Everything must fit under the stock IROC hood too.
A Mini Ram isn't out of the question but I wonder if it would really help with my concerns.
Most of this is straight forward but I am not sure whether to go with a 4 barrel TB or a front mount TB with an elbow. I have a great 58mm TB but would consider a LS style TB it that would be better. There are low profile elbows but then there goes the distribution question. If I go with a conventional style 4 barrel TB then the elbow to the filter would be the question.
Oh by the way I will still be using nitrous. So, probably a plate style. I have the ability to machine the intake or plate adaptor if necessary for hood clearance.
There are all the ancillary issues like fuel rails, regulator, TPS, IAC and all. I am running Bob's EBL ecm and really like it but would consider other systems if really necessary. I do need to keep cost in check to a degree so anything I can reuse will help out there too.
Please give your comments and experience if you have any. This has been a long time coming so I really am looking for input.
I have the Accell pro ram with the 4 barrel throttle body and normal small diameter air cleaner element and it would not clear the stock hood. It might clear a stock hood if I were to part with the 4 barrel throttle body and use a drop style intake elbow and an LS throttle body but I don't think I could run a nitrous plate between the elbow and intake.
One of those elbows is going to run you $200 new. The LS throttle body could be had for cheap though.
As the title says, I'm looking for advice when going from the Holley Stealth Ram to a single plane. I looked through the single plane thread but it's been a long time and a lot of other intakes/throttle bodies are available now and I know lots of you folks have installed a single plane EFI intake by now.
My goal is better air/fuel distribution. Picking up some power would be great too. I am also using nitrous with a single nozzle in front of the throttle body and have wildly different plug readings. I think it's due to the front mount TB and the bosses inside the plenum. I could go direct port but still have distribution issues at part throttle. There are other minor issues like not being able to remove my distributor cap with the plenum in place and I believe a single plane layout would help with those type issues.
I like the looks of the HSR and the filters in front of the radiator. I am OK with a single plane's looks but would still like to retain the air filter setup although it negotiable. Everything must fit under the stock IROC hood too.
A Mini Ram isn't out of the question but I wonder if it would really help with my concerns.
Most of this is straight forward but I am not sure whether to go with a 4 barrel TB or a front mount TB with an elbow. I have a great 58mm TB but would consider a LS style TB it that would be better. There are low profile elbows but then there goes the distribution question. If I go with a conventional style 4 barrel TB then the elbow to the filter would be the question.
Oh by the way I will still be using nitrous. So, probably a plate style. I have the ability to machine the intake or plate adaptor if necessary for hood clearance.
There are all the ancillary issues like fuel rails, regulator, TPS, IAC and all. I am running Bob's EBL ecm and really like it but would consider other systems if really necessary. I do need to keep cost in check to a degree so anything I can reuse will help out there too.
Please give your comments and experience if you have any. This has been a long time coming so I really am looking for input.
I ran a hurricane manifold on my 412 for a little bit with an edelbrock elbow.
I flipped the throttle body up-side-down and it cleared the stock hood with room to spare.
You're not gonna find one that mounts forward though and clears. Any 1206 port single plane is going to be over 6" tall, so it is what it is.
A Mini Ram isn't out of the question but I wonder if it would really help with my concerns.
If you're looking for good A/F distribution (at least below 1000 rpm), the Miniram is not the way to go (at least with batch fire injection). Do a search on "split BLM beast" and you'll see what I had to go through to get decent distribution without going to sequential injection.
Although above 1000 rpm, it does pretty good. I've pulled my plugs before after coming home from a drive and they look pretty uniform (even before the modification I made in that "split BLM best" thread.
First of all, thanks for the input.
Joe- So the throttle body facing forward wouldn't clear, but at the passengers side it does. Interesting. I have seen that configuration before but thought you just did it for intercooler routing. I really do like that elbow with the vane inside. I wonder if clearance would be as much of a challenge with the twin 58 TB?
Yes I have read the split blm thread and yes I am still running batch. This is one of the reasons I mentioned the ecm. If going to a different management system will make a difference I am open to it. I have only tuned the 65 and now EBL so there'd be a learning curve there but maybe it's worth it.
I don't spend much time below 1000 except at idle. Cruise is 1500 about the lowest and usually ~2k.
I don't spend much time below 1000 except at idle. Cruise is 1500 about the lowest and usually ~2k.
Same here. Just for me, since I'm running a mild cam, it was pissing me off that the Miniram was cheating me out of a smooth idle... lol.
Otherwise what's the point! I'd just opt for a bigger cam and get the power if I'm going to have a sh*tty idle.
Any rate, I'm actually idling in open loop now too. Seemed that no matter how much I got the A/F distribution dialed in at idle, I simply could NOT get the off-idle tip-in crisp enough for my liking with closed loop.
With open loop idle and a pre-programmed AFR, transition is sharp as a tack now.
First of all, thanks for the input.
Joe- So the throttle body facing forward wouldn't clear, but at the passengers side it does. Interesting. I have seen that configuration before but thought you just did it for intercooler routing. I really do like that elbow with the vane inside. I wonder if clearance would be as much of a challenge with the twin 58 TB?
Yes I have read the split blm thread and yes I am still running batch. This is one of the reasons I mentioned the ecm. If going to a different management system will make a difference I am open to it. I have only tuned the 65 and now EBL so there'd be a learning curve there but maybe it's worth it.
I don't spend much time below 1000 except at idle. Cruise is 1500 about the lowest and usually ~2k.
Yeah the hood curves downward too far by the time you are hanging out by the front china wall.
I think a twin 58 is not as tall, but not many elbow options exist. The LSx throttle bodies are stupid cheap (95mm, 105mm, etc) so I went with that at the time.
I'm actually running a miniram now.
I also own a LT1 vette, which is fully sequential. The injector trims on the LT1 intake are quite interesting. I'm running batch right now on my Miniram, but I may upgrade to an MS3 eventually, especially now that I've done away with the distributor and am running a crank trigger.
Any rate, I'm actually idling in open loop now too. Seemed that no matter how much I got the A/F distribution dialed in at idle, I simply could NOT get the off-idle tip-in crisp enough for my liking with closed loop.
What ECM?
I idle around 800 with a 276* cam on my 412. I do not idle closed loop, but I let autotune dial in my VE table at idle based on my AFR table. Using a wideband o2.
My car is crisp off idle. In fact it's a little too crisp. lol.
With open loop, I'm idling at 600 rpm in gear with a factory LT1 Vette torque converter and a 262 cam. With closed loop, I couldn't get it to idle below 725 while delivering a sufficiently crisp off-idle transition.
It didn't matter how I tuned the VE tables. As anyone who's read my posts... For years, I was jacking with the Idle O2 threshold constants every which way from Sunday, along with the AE tables trying to dial in that transition. And it got worse with temperature.
Now that's not to say it was bad necessarily... It was actually pretty decent and "acceptable" and if there was no other recourse, I could have lived with it. Someone else driving the car probably would have said "what's wrong with it? Feels fine to me!".
But being as picky as I am, after discovering the open loop idle function in S_AUJP, I finally got it perfect. Now I'm idling consistently at about 13:1 AFR and the engine really loves it. I've been able to dial back the AE a little too. It was factory LT1, but richer by about 10-15%. Now I'm pretty much at factory LT1 AE settings across the board.
Matter of fact, the improvement from open loop idle was so dramatic that I actually had to lean out the AE by about 20% at delta TPS of 50% and delta MAP of 50 kPa. At WOT launch from a stand still I was getting a rich bog (WB was bottoming out at 10:1 momentarily, which probably meant I was going even richer, but out of the range of the gauge).
I will say too, that understanding the MAT tables and getting them dialed in for the cold air tube and relocated MAT sensor also had a very profound effect on how the car runs. I think between that and the open loop idle, I really have finally tamed this Miniram beast.
Yeah, my throttle is sometimes "too crisp"... to the point of having a hair trigger... lol. But I kind of like it. When I rap on the throttle, the car just jumps off the line. I've learned out to feather it for light take offs though.
Yeah the hood curves downward too far by the time you are hanging out by the front china wall.
I think a twin 58 is not as tall, but not many elbow options exist. The LSx throttle bodies are stupid cheap (95mm, 105mm, etc) so I went with that at the time.
I'm actually running a miniram now.
I also own a LT1 vette, which is fully sequential. The injector trims on the LT1 intake are quite interesting. I'm running batch right now on my Miniram, but I may upgrade to an MS3 eventually, especially now that I've done away with the distributor and am running a crank trigger.
-- Joe
I think I would have to make a custom elbow to run the twin 58. But I could dial in in just right for clearance etc.
How's that mini ram on batch? The HSR with EBL really idles good @ 775 and my cam. Not glass smooth but good and pulls ~40-45 map. Great off idle and even pulls down to 1k. Remember I run a stick shift so it isn't forgiving. I can live with how it runs, just has trouble running wet with the nitrous. Maybe I should give up the juice and run boost?
Oh and it runs in closed loop, idle and cruise. I haven't had a lot of problems with idle and my cam. I am still working with the IAT/CT blend table in EBL. It seems to be great then off as the season changes.
Times are hi 7's na and 7.30-40's at 99-100 on the nitrous. So it's making decent power for a 3700 lb slug.
But getting back to the original topic, do you think a single plane will run better and be more consistent once dialed in?
Yeah, my throttle is sometimes "too crisp"... to the point of having a hair trigger... lol. But I kind of like it. When I rap on the throttle, the car just jumps off the line. I've learned out to feather it for light take offs though.
My car just melts the tires. Every gear. It's not possible to go wide open throttle on street tires, in any gear, at any speed.
I think I would have to make a custom elbow to run the twin 58. But I could dial in in just right for clearance etc.
How's that mini ram on batch? The HSR with EBL really idles good @ 775 and my cam. Not glass smooth but good and pulls ~40-45 map. Great off idle and even pulls down to 1k. Remember I run a stick shift so it isn't forgiving. I can live with how it runs, just has trouble running wet with the nitrous. Maybe I should give up the juice and run boost?
I'm running an auto in this car now, so it's a little more forgiving. Converter slips like hell. When I had the miniram with the 224/230 cam in the other Corvette with the 6 speed it sucked *** at low RPM/throttle. It would surge and buck and jerk with the '730 PCM running S_AUJP.
Both cars were supercharged. Both had different plugs that were richer or leaner lol.
I eventually swapped it for this setup:
Which ran really well.
I have not touched the stock stuff (other than LT1 flash stuff) in a decade now. ULTM8Z put way more effort into getting his running right than I would have. Again, my next move will be full sequential because it just makes life easier.
Saw big gains on a single plane vs miniram on a hot 406 stick car. 2 tenths and 2 mph on a mid high 10 sec car na. But to be fair the miniram was 1205 port barely lol heads were 1206. Single plane was port matched to the heads. Ran an elbow of decent radius. Was in a 94 firebird so not exactly a fair comparison for hood clearance but it fit.
Joe, what ecm are you running sequential? I know I've seen your posts somewhere. MS? What intake, elbow and TB are in that last image?
Orr, do you remember what intake, elbow and TB in that combo. Cam?
Mine won't "melt tires in any gear" but it traction limited on street tires. 1st is not possible and 2nd slips usually. Which is one of the challenges tuning WOT. 3rd gear will take full throttle but at the top I'm running 100 MPH. Leave me to have to tune at the track so it takes a lot longer.
Joe, what ecm are you running sequential? I know I've seen your posts somewhere. MS? What intake, elbow and TB are in that last image?
I'm not yet running sequential, as I only have 4 injector drivers. I need to add I/O, or upgrade to MS3. I'm running megasquirt.
The elbow is custom, I designed it back in 2008 and had this guy Aaron from 6061.com make it. It was designed to fit under the stock hood of a C4, with like minimum valvecover clearance, etc. The angle was what was decided to be best based on some flow modeling a kid I knew from MIT did at the time.
There's a dyno shop about 10 minutes from my house, which I may do some upper RPM tuning on.
Joe, what ecm are you running sequential? I know I've seen your posts somewhere. MS? What intake, elbow and TB are in that last image?
Orr, do you remember what intake, elbow and TB in that combo. Cam?
Mine won't "melt tires in any gear" but it traction limited on street tires. 1st is not possible and 2nd slips usually. Which is one of the challenges tuning WOT. 3rd gear will take full throttle but at the top I'm running 100 MPH. Leave me to have to tune at the track so it takes a lot longer.
I wanna say victor e efi, but cant be positive. It was a long time ago. Bullet solid roller around mid 250’s deg on intake i think. Ported afr heads flowed 308 cfm. Elbow i think was a low profile simple 90 deg
I wanna say victor e efi, but cant be positive. It was a long time ago. Bullet solid roller around mid 250’s deg on intake i think. Ported afr heads flowed 308 cfm. Elbow i think was a low profile simple 90 deg
I've been looking at the Victor E and Holley. Holley specs shows 5.5" height and Victor E shows 4.5" but I am doubting that dimension. Probably closer to 5.5".
Both list the port dimension as barely 1204 size. My AFR heads are closer to 1206 and that is what my HSR is ported to. I expect that either one can be port matched to the AFR's, somewhere between the 1205 & 1206.
If the Victor is really 4.5" tall it would be easier to get it to clear. Both are about the same cost.
Another option is the RHS intake. I can't find height spec on it but the carb version in a CC article is listed at 5.5". So that's the height I am working around.
Elbows. I've looked at the typical ones but then Edelbrock has a "box" style that looks interesting.
I've been looking at the Victor E and Holley. Holley specs shows 5.5" height and Victor E shows 4.5" but I am doubting that dimension. Probably closer to 5.5".
Both list the port dimension as barely 1204 size. My AFR heads are closer to 1206 and that is what my HSR is ported to. I expect that either one can be port matched to the AFR's, somewhere between the 1205 & 1206.
If the Victor is really 4.5" tall it would be easier to get it to clear. Both are about the same cost.
Another option is the RHS intake. I can't find height spec on it but the carb version in a CC article is listed at 5.5". So that's the height I am working around.
Elbows. I've looked at the typical ones but then Edelbrock has a "box" style that looks interesting.
Anyone used this style?
I think that elbow is rated for like 350hp max.. Lots of threads on the box style elbows from back to like 2008/2009 on ls1tech and turbo forums.
The high flow (3849 I think) elbows are rated to like 1800 cfm, but they won't clear anything remotely near a stock hood.
BTW, Looking at my notes, I milled down the intake manifold on that Corvette to 5.125" and the elbow was 4.75".
The kid I sold the car to traded it for a '79 Camaro. The new owner ripped the EFI off, bought an ugly 6" cowl hood, and did a blow through carb. He also replaced the grandsport rims for some ugly ***** 20" crap. Makes me wish I kept it. Or parted it out.
I think that elbow is rated for like 350hp max.. Lots of threads on the box style elbows from back to like 2008/2009 on ls1tech and turbo forums.
The high flow (3849 I think) elbows are rated to like 1800 cfm, but they won't clear anything remotely near a stock hood.
BTW, Looking at my notes, I milled down the intake manifold on that Corvette to 5.125" and the elbow was 4.75".
The kid I sold the car to traded it for a '79 Camaro. The new owner ripped the EFI off, bought an ugly 6" cowl hood, and did a blow through carb. He also replaced the grandsport rims for some ugly ***** 20" crap. Makes me wish I kept it. Or parted it out.
-- Joe
Well it didn't look like it would flow like a good radius elbow would.
I am used to making modifications to make it fit. Heck, I even milled a 1/4" off my HSR base to improve hood clearance. Now it only rubs a modest amount.
And in regard to people doing stupid things to all your hard work. It just doesn't make sense. Took a step back in technology and then try to "modernize" it with big rims which, in my opinion, should never be on a third gen car. Maybe it's ok for some but I would hate to see it done to mine. I was super skeptical about putting 18" rims on mine. It just doesn't seem right. It's kinda like your daughter dating a thug- what a waste!
My 396 SB stroker is in car but not yet broken in. During the engine swap I had 5/16 inch milled off the bottom of the low profile carb/blower hat(ebay). That caused the hat to drop onto the R angle coolant fitting at front of the intake(Vic jr efi) so found another brass fitting(lower profile) and with a bit taken off it and it cleared the hat. The hat is facing forward and I have a KN filter on it with a 45d angle 3.5 inch spectre elbow. The TB is a 1000cfm Edelbrock. Car is an 84 vette with less hood clearance than later models.
My 396 SB stroker is in car but not yet broken in. During the engine swap I had 5/16 inch milled off the bottom of the low profile carb/blower hat(ebay). That caused the hat to drop onto the R angle coolant fitting at front of the intake(Vic jr efi) so found another brass fitting(lower profile) and with a bit taken off it and it cleared the hat. The hat is facing forward and I have a KN filter on it with a 45d angle 3.5 inch spectre elbow. The TB is a 1000cfm Edelbrock. Car is an 84 vette with less hood clearance than later models.
Ok, just to make sure I'm following you...
Victor Jr EFI manifold with an Edelbrock 4 bbl throttle body and a blower hat/elbow which you milled down for hood clearance. Then, a KN filter in front of the hat. Did I get that right?
I'd like the same basic intake/TB/hat combo then I could hook it up to the stock Y and filter assembly. With a Camaro I should have more clearance than your Vette.
This is B4 the new engine was dropped in. I have made the adjustments this season.
I saw a pic of a similar set up but the hat was clocked to passenger side but aimed 30deg to the firewall then angled back to where the shock towers would be and attached there placing the come filter low and at front of the of the engine. My hood will not allow that as it is sloping downward at the sides. Dead center forward has most clearance. Now you can see how dropping the hat will hit the R angle coolant . I believe we moved the fuel lines fitting on pass side by adding a R angle.
04-22-2018, 05:56 PM
