This thread was started to seek input from people who might have run across intakes systems for LT1's with longer runners, whether one off or production pieces. Thanks to the guys who posted info. on some of their stuff that was relevant. The idea is to use the best manageable combination of off the shelf or in some instances possibly fabricated parts to produce a 383 with good top end power and max. midrange with solid low end. The variable resonance stuff some of us have been bouncing ideas around about is the BEST way to enhance the engine's torque width that I'm aware of. Construction of such gizmotrons happens to be one of my talents. I used to do stuff on the level of making an intake with dual length runners separated by valves for a living and still do such things as a hobby from my home machine shop. I guess that means I'm coming from left field compared to most of the readership on here in regards to doing such things on a pretty regular basis. Just for the challenge and enjoyment mostly.
I do think I'm pretty darn smart but I don't have ALL the answers The problem with a couple of my threads ( in my opinion) has been people hijacking them and injecting self serving propoganda that wasn't relevant or accurate. Self serving or even arrogant is fine but misleading and destructive are not. Stuff like " I " know the best and only correct way and any other way is foolish, or the only way real hotrodders do it is...., or a 383 ain't worth a bildin iffin yas don't put a huge cam and 250 cc heads, or doing it some other than the normal way is a waste of time. A difference of opinion is one thing, but trying to invalidate someone else's approach or viewpoint without addressing it directly or logically is annoying. If trying to keep my thread going and on track means butting heads and information with other people then that's OK with me. I must be disrupting the normal order around here for some people, it seems like there's a lot of energy being exerted pushing their agendas. This comes at the expense of the usefulness or accuracy of the information in the thread in some cases and that pisses me off .
This thread wasn't started with me intending to build an intake with valves or an exhaust with variable back pressure but I may well do both in the end. Someone else may decide they want to tinker in this direction and may do something some of us are interested in and can learn from.
I'm still interested in hearing from people who have something relevant to say in this area. Keep it coming, this thread has been pretty fun! I reject the reality ram rodded by some people and proselytize my own version of reality ( which I happen to think is closer to being real or true).
Regards, Michael

 

This:


...seems remarkably similar to this:


Now what I'd be curious to see is a cutaway picture of an LT5 intake and see if the runners protrude into the intake plenum at all like the first rendering. Does anybody happen to know off hand what the runner length on an LT5 intake is?

I'm no airflow expert, but my gut instinct tells me that the CAD drawn intake might have turbulence issues.

(And yes, before anyone decides to throw flame darts I realize that an LT5 intake doesn't fit an LT1.)

 

Well thats a Wilson design and he don't design thing that don't work and sell them.
He IS the master whether it's F-1.Indy Car or Pro Stock he IS the master.

A 4.6 intake is like that on the inside and they work,sometimes TOO good.

 

Why 1racerdude thanks for the interesting graphical display you setup there. I'm not sure on the runner length on the LT5 motor. I think I've read that the LS1 runners are close to 15" long vs. around 21" for the TPI intakes. The plenum is certainly wide enough for the runners to extend in their a ways. Anybody have a link to a cutaway of the LT5 manifold?

 

The next time you call people dummies, and flame people, your posting privilages are going to be affected. The agreement you read when you signed up said you would not engage in flaming.

 

The LS1 has 8inch runners I believe, the Accel Super Ram has 15inchs or runner length and most SBC Single planes have 5-6inch runners.

 

Do you know if they plan on producing this intake?

 

Call them and talk to Ted he will know.

 

The LS1 intake is being produced now.


The LT1 intake posted in this thread.....no.



David

 

I read a few tests on the TPI vs HSR vs Single plane, and the torque output from the modified TPI is shocking.....but as every one knows the long runners die at about 5600. Big runners, ported base and 21" runners make 30 ftlbs more that a superram, and a superram makes about 30ftlbs more than an lt1 intake. If you could somehow have short ram tubes controlled with a butterfly valve to the plenuum to bypass the long runners at 5500 rpm(use a window switch). Just a pipe dream for my resources...but food for thought.....
It looks like a dual plane manifold is very close to the best all around compromise up to 6500 rpm, really good torque and very little drop off; however I heard there were problems with a dual plane and port injection....not sure why. I would love to use a RPM air gap with an elbow but the super victor or HSR is more economical( I have hood clearance). I was hoping that an HSR(holley stealth ram) would match the RPM airgap in torque(both have about 6" runners I think) but it looks like the rpm beats it till about 6100 rpm. Now I have not seen a direct HSR vs RPM vs LT1 vs Super victor... that would be a nice test.....

Car craft on their web site has a test on ported vortec heads. They switch between a RPM and a Super victor.... the Victor gets smoked up to 6500 RPM where the engine quits making power 350ci 235/235 lunati cam.

 

That's not an LT1 intake anyway, the runners are spaced for the LS1.

 

I was referring to the LT1 wilson manifold that is ours pictured on the 1st page.


It will not be produced, it is a one off deal


David

 

Gotcha. It's a shame though, that looks like a good performer.

 

a better comparison on that test might have been an RPM air gap vs a victor jr and then a torker thrown in the mix just to see what happens. only time i see anyone with a torker these days is pontiac swaps into third gens so they clear the stock hood.

edit: they don't make a vic jr for vortec heads, do they?

 

CrystalSS, I've been thinking along the exact same lines you outlined in your most recent post. The potential powerband width using a well designed dual length runner setup could be awesome for a street car. I once installed a completely stock TPI setup with an electromotive ECM on a very hot 383 ( aftermarket heads, big roller cam and very high compression as it ran off aviation fuel). It produced super midrange for such a large cam/head package but completely choked out in the mid 4k RPM range. The long and "skinny" TPI runners made a load of midrange even with a large, lopey cam. But no topend to speak of, tried to warn him.
I suspect that if you had the flexibility of going with dual runners that the width of the torque peak of the different runner lengths would allow more specialization in the selection of the runner dimensions. Using a set of really long runners ( TPI style) combined with a really short set ( LT1 style) that were optimized might make for a crossover point closer to 4500 or 5000 RPM's. Just speculating as I haven't put a lot of thought into it but based on my experience the longer runners might produce more midrange and lowend if they were a shade smaller cross sectional diameter than the biggest aftermarket TPI stuff ( that stuff may be compromising some low end for reasonable top end). You might wind up in a situation where the overlapping torque peaks of the two different runners would allow greater tuning specialization of the long ones so they were optimized more for mid/low with little thought of higher RPM effectiveness. It would certainly be worth researching to see if it might be more effective to have a smaller diameter "tube" for the bulk of the long runner that Y'ed into a larger diameter short runner just upstream of the injector. Just a thought.
The more I think about this the more I think I'll build one.
Anybody else have any educated guesses on how they'd setup the runners in such a gizmo?