Tunnel Ram tuning

[440Duster]

Once again, Thanks for all the input. Lots of info to digest. Considering I’m really happy with the idle, transition and cruise tune, I’ve decided to move forward with reconnecting the secondaries and seeing where I’m at. Then tuning WOT with the secondary jets.

That being said, I am the kind of guy that is always thinking “what if…” The 1:1 idea and the base tune that In-Tech has posted really has peaked my interest! I think I will probably play around with that over the winter and I’m sure I will have questions as that transpires. I figure worst case scenario I can always fall back on this current tune.

[RW TECH]

Once again, Thanks for all the input. Lots of info to digest. Considering I’m really happy with the idle, transition and cruise tune, I’ve decided to move forward with reconnecting the secondaries and seeing where I’m at. Then tuning WOT with the secondary jets.

That being said, I am the kind of guy that is always thinking “what if…” The 1:1 idea and the base tune that In-Tech has posted really has peaked my interest! I think I will probably play around with that over the winter and I’m sure I will have questions as that transpires. I figure worst case scenario I can always fall back on this current tune.

Something to keep in mind....If you're trying to read spark plugs, you're pissing up a rope. Contrary to popular beliefs and arguments, you can have plugs that "look good" from a couple of cylinders with one happy and the other ready to eat itself alive. NOBODY in professional motorsports really wastes their time with that because over time they've learned it is not an accurate way to understand what is really happening.

[ClassAct]

Once again, Thanks for all the input. Lots of info to digest. Considering I’m really happy with the idle, transition and cruise tune, I’ve decided to move forward with reconnecting the secondaries and seeing where I’m at. Then tuning WOT with the secondary jets.

That being said, I am the kind of guy that is always thinking “what if…” The 1:1 idea and the base tune that In-Tech has posted really has peaked my interest! I think I will probably play around with that over the winter and I’m sure I will have questions as that transpires. I figure worst case scenario I can always fall back on this current tune.

It maybe time to consider annular boosters. With current fuel formulation and a cold air intake you may be fighting an uphill battle with down leg boosters. Also, consider a burr finish on the intake manifold. You’d be surprised what that will do fuel issues.

[440Duster]

Once again, Thanks for all the input. Lots of info to digest. Considering I’m really happy with the idle, transition and cruise tune, I’ve decided to move forward with reconnecting the secondaries and seeing where I’m at. Then tuning WOT with the secondary jets.

That being said, I am the kind of guy that is always thinking “what if…” The 1:1 idea and the base tune that In-Tech has posted really has peaked my interest! I think I will probably play around with that over the winter and I’m sure I will have questions as that transpires. I figure worst case scenario I can always fall back on this current tune.

Something to keep in mind....If you're trying to read spark plugs, you're pissing up a rope. Contrary to popular beliefs and arguments, you can have plugs that "look good" from a couple of cylinders with one happy and the other ready to eat itself alive. NOBODY in professional motorsports really wastes their time with that because over time they've learned it is not an accurate way to understand what is really happening.

Ok, please explain the (my) alternatives to reading plugs.

[RW TECH]

what is really happening.

Ok, please explain the (my) alternatives to reading plugs.
[/quote]

Your best DYI alternatives are a vacuum gauge & tachometer to get idle set, and a rolling road dyno with a load cell for TQ to set part throttle. Or, you can do part throttle on a public road and basically land on whatever delivers the best balance of fuel economy and TQ.

WOT should also be done on a dyno that measures TQ. You can try it at a race track but you won't be able to pinpoint what fuel & spark the engine wants at peak TQ vs peak HP and above peak RPM.

The wideband sensor readings then become a reference, and you should put the sensor in every primary to ensure you don't have anything "gross" going on in any particular cylinder.

[440Duster]

what is really happening.

Ok, please explain the (my) alternatives to reading plugs.

Your best DYI alternatives are a vacuum gauge & tachometer to get idle set, and a rolling road dyno with a load cell for TQ to set part throttle. Or, you can do part throttle on a public road and basically land on whatever delivers the best balance of fuel economy and TQ.

WOT should also be done on a dyno that measures TQ. You can try it at a race track but you won't be able to pinpoint what fuel & spark the engine wants at peak TQ vs peak HP and above peak RPM.

The wideband sensor readings then become a reference, and you should put the sensor in every primary to ensure you don't have anything "gross" going on in any particular cylinder.
[/quote]
Thanks again for the reply, and as much as I would love to have the ability to use all of these alternatives I’m limited to a tachometer, vacuum gauge, and a wideband on one side at a time. And as for a dyno I only have access to the ole “butt dyno”. I do have a Dragy that is my only option for track time. Oh and reading plugs or “pissing up a rope” as you call it. All of these things combined have got me this far and I’m happy with the results so far. I’m just an old gear head who plays in his garage a couple of hours a weekend and drives the crap out of this old Jalopy. I appreciate your input and no disrespect is intended or implied.

[RW TECH]

I appreciate your input and no disrespect is intended or implied.

None taken & hope you have good luck in what you're doing.

[mopardave]

I use the afr readings as a reference. I had a 408 that was fastest at 12.8 and this 511 was fastest at 13.2-13.3. Current best is 10.06@134.

[Miszny]

I have a 511 with 12.5:1 compression and a 270/276@50 sft. I use an Indy cast tunnel ram with twin BLP 650’s that flow about 750, they were built by Thumpercarbs. I played with the power valve set up a whole summer. 4 power valves. I had it doing everything quite well, but after trying square jetted their is no going back. It does everything perfect. It idles at 14.0, cruises 14.0 and wot is 12.8 with a .030hsb and 13.2 with a .032hsb. Jetting is 83 square using BLP jets, Holley jet would be 78. Squirted are 35. I think it’s a bit smoother cruising and transition is awesome. Being squared it comes on faster and harder when flat footed than it did when using PV’s. Using .031ifr and .70ib

I sent you PM about your carbs setup…

[Steve K]

I have two cars with tunnel rams and one with a dual quad set up. One is a 406 sbc with a 243/254 hydraulic roller, the other one is a 427 SBC with a 263/272 solid roller and the third is a 355 with a Thumper cam. I run Edlebrock 1405's on all these engines (front carb on the dual quad is a 1406). Other than metering rod and spring changes on the TR's when run on the dyno and out of the box eddys on the dual carb I've done no tuning. These are street cars as well and when necessary I'll bang through gears just to scare the sh!t out of my passengers and myself. I also run manifold vacuum advance on these engines. No disrespect to the Holley crowd but they are a lot of work to tune by the looks of it. Other than that, have a great day. It's winter where I live...

[F-BIRD'88]

I have two cars with tunnel rams and one with a dual quad set up. One is a 406 sbc with a 243/254 hydraulic roller, the other one is a 427 SBC with a 263/272 solid roller and the third is a 355 with a Thumper cam. I run Edlebrock 1405's on all these engines (front carb on the dual quad is a 1406). Other than metering rod and spring changes on the TR's when run on the dyno and out of the box eddys on the dual carb I've done no tuning. These are street cars as well and when necessary I'll bang through gears just to scare the sh!t out of my passengers and myself. I also run manifold vacuum advance on these engines. No disrespect to the Holley crowd but they are a lot of work to tune by the looks of it. Other than that, have a great day. It's winter where I live...

Bang on, The Eddy and Carter carbs are very street friendly on street/ strip Tunnel Rams cars.
I do prefer the larger ones for power.
2x750 eddys is non too much even on a 350 sbc with TR.
Never tried it but I bet the Street Demon series of air door type carbs are also easy to dial in and run on a street strip TR or high rise Dual Quad.

[Steve K]

I would have gone with 750's as well but I had all these Edelbrocks sitting around and not enough cars. For what I do with them the 1405's do the trick. I did remove the choke plates on the TR's and the rear carb on the dual quad. Not sure if it helps but I had a few minutes one afternoon soooo, as the saying goes "lets fix what aint broke"

[mopardave]

That is some good info and im thinking about moving the o2 to the pass side and a few inches behind the end of the collector. What i found at the track was thru the 1/4 traps it went faster when i changed the high speed bleeds from .030 to .032 bumping the afr up to 13.2-13.3. I found the same results using a single 1100 Dominator.

[1972ho]

https://youtu.be/7Iq1B-2paCs Have you seen this?