285 whp!

[RallyBob]

Originally Posted by RallyBob

Jack had previously chopped up a spare stock EG33 intake manifold, and I got to looking at it the other day. In terms of basic design, it looks very good, there are very generous transitions from the plenum to the runners...factory 'trumpets' if you will. The crossover valve is a moot point for our application. The engine's running vacuum is already lower than standard, and the engine rarely sees low rpms on the track. So the crossover is always open as it is. As well, the intended original application was for a relatively heavy Grand Touring vehicle with an automatic transmission, so down-low torque was a priority to the engineers.

None of those factors apply now, so my thoughts are to eliminate the crossover, and utilize one common plenum at all times. A trial bit of math also shows that the plenum volume is very small relative to the engine's displacement. I'd like to investigate the effects of changing the plenum volumes to work with the improved breathing and extended powerband of the modified engine. If possible, I'd like to make it modular (bolt-on plenum addition) for testing, so I can determine which is best for our needs. Then , once the proper plenum volume is determined, I'll make a permanent version with reworked (slight porting and polishing) internal runners.

I'm thinking of trying 80%, 90% and 100% plenum volumes...2.64 litre, 2.97 litre, and 3.3 litre. Plus or minus a few CC's....

The first step will be to CC the stock plenum, and go from there.

It won't be tomorrow, but over the next 4-6 weeks I'll see if I can free up some time to tackle this project, and will post the progress here.

While I have had no time to work on this project personally, I spoke with Jack about it, and he had XXTuning's current fabricator (Sean) modify the stock intake per our discussions. What this means is the entire center plenum area is basically open, the IRIS is gone altogether, and the manifold lost 7 lbs of weight too! The forward-facing 'wall' area is curved to direct air to each runner side, but other than that the entire plenum is a huge box now. Plenum area has been basically tripled compared to stock.

I sort of like the 'consultant' aspect of this for me...I didn't need to get my hands dirty at all!

He didn't make the plenum area 'adjustable' like I had originally hoped (I sometimes tend to complicate things by making them overly adjustable), but I think we're likely to see a significant change, good or bad.

[SVXRide]

Bob,
Cool! Any pics of the final version? Did Sean end up shortening the "legs" of the intake in the process of making the "body" bigger?
-Bill
p.s. the EG33R pics you've posted are great! Any chance you can add pics of how the steering quickener was added in?

[RallyBob]

Originally Posted by SVXRide

Bob,
Cool! Any pics of the final version? Did Sean end up shortening the "legs" of the intake in the process of making the "body" bigger?
-Bill

The legs/lower runners are the same length as stock. Only the center plenum area is modified. I have no pics of it, and only just saw it yesterday for the first time.

p.s. the EG33R pics you've posted are great! Any chance you can add pics of how the steering quickener was added in?

All those pics are rather old...two-plus years most of them. My old camera died a slow death thanks to repeated droppings....

I have a new camera, but with no software to be able to upload new pics...sort of useless actually.

I tried to take video of the quickener install a few weeks back. It is virtually unseeable once installed, I couldn't even get my camera into the space unde the dash. It literally is completely hidden from view in the car.

It simply entailed shortening the steering column itself, and installed the quickener in the column prior to the firewall via splined and welded couplers. A bracket welded to the outer column's steel shell secures the quickener body in place so the body itself can't rotate.

[RallyBob]

A tiny update.

The customized large-plenum intake manifold has been test-fitted and the engine run. No tuning or dyno time was performed, as an interesting dilemna showed itself.

When the throttle is blipped, the plenum top and bottom plate (.125" 5052 aluminum) gets sucked inwards by almost 1/2". I don't really see how a piece of (roughly) 10" x 10" aluminum plate that's .125" thick bends so much, but it un-nerved Jack enough that he removed the intake and never bothered to dyno the car for fear of cracking the intake @ the welds and sucking broken-off material into the engine. So the intake plenum will have to be revised somewhat, probably with some centrally located supports welded in place. Then it will get dynoed. I think it will be promising.

I'm almost thinking this is showing that the twin TB's are restricting the flow to the intake, although that is admittedly a bit tough to fathom as they're pretty darn big. But then again I have nothing else to compare it to...I have never run another EG33 with cams and headwork so I can't really comment on the VE potential of this engine when all the mods are in place.

Another interesting side effect is the induction noise at idle is now significant. You can truly hear the camshaft overlap pulses inside the plenum. I guess the stock plenum divider wall significantly dampened the pulses previously.

I'm open to comments and input from other forum members.

[GreenMarine]

Originally Posted by RallyBob

I'm open to comments and input from other forum members.

I don't have any comments other than I hope you are keeping track of everything you are doing. Because as soon as I have the $$$ I'm coming to you for a mild build on my engine!!

~ Chris

[TomsSVX]

Originally Posted by RallyBob

A tiny update.

The customized large-plenum intake manifold has been test-fitted and the engine run. No tuning or dyno time was performed, as an interesting dilemna showed itself.

When the throttle is blipped, the plenum top and bottom plate (.125" 5052 aluminum) gets sucked inwards by almost 1/2". I don't really see how a piece of (roughly) 10" x 10" aluminum plate that's .125" thick bends so much, but it un-nerved Jack enough that he removed the intake and never bothered to dyno the car for fear of cracking the intake @ the welds and sucking broken-off material into the engine. So the intake plenum will have to be revised somewhat, probably with some centrally located supports welded in place. Then it will get dynoed. I think it will be promising.

I'm almost thinking this is showing that the twin TB's are restricting the flow to the intake, although that is admittedly a bit tough to fathom as they're pretty darn big. But then again I have nothing else to compare it to...I have never run another EG33 with cams and headwork so I can't really comment on the VE potential of this engine when all the mods are in place.

Another interesting side effect is the induction noise at idle is now significant. You can truly hear the camshaft overlap pulses inside the plenum. I guess the stock plenum divider wall significantly dampened the pulses previously.

I'm open to comments and input from other forum members.

Why no Dyno??? If the aluminum is flexing, best to take all the vacuum out of it by opening those throttle plates all the way

Keep us updated

Tom

[oab_au]

Originally Posted by RallyBob

A tiny update.


When the throttle is blipped, the plenum top and bottom plate (.125" 5052 aluminum) gets sucked inwards by almost 1/2". I don't really see how a piece of (roughly) 10" x 10" aluminum plate that's .125" thick bends so much,
I'm almost thinking this is showing that the twin TB's are restricting the flow to the intake, although that is admittedly a bit tough to fathom as they're pretty darn big. But then again I have nothing else to compare it to...I have never run another EG33 with cams and headwork so I can't really comment on the VE potential of this engine when all the mods are in place.

I'm open to comments and input from other forum members.

10"x10"=100 sq" X 10lbs/sq" =1000lbs. Yes I guess it would flex a bit.

The engine will achieve a VE of 106%, in its standard state, at higher rpms it will achieve 110%.

Harvey.

[Trevor]

Originally Posted by oab_au

10"x10"=100 sq" X 10lbs/sq" =1000lbs. Yes I guess it would flex a bit.

Harvey.

When the throttle is blipped, the plenum top and bottom plate (.125" 5052 aluminum) gets sucked inwards by almost 1/2"

A positive 10 lbs/sq” is in no way applicable.

[shotgunslade]

Saw Jack and his car at at Pocono today. Said he had dynoed the car at 300whp recently. Also said he is still having some overheating problems, despite having a 25 psi radiator cap. He confirmed that he is going for individual throttle bodies for each cylinder.

I also found out that a 20 psi radiator cap is incompatible with the stock radiator. More about that unfortunate discovery when I report on my track day at Pocono later this week.

[SVXRide]

Originally Posted by shotgunslade

I also found out that a 20 psi radiator cap is incompatible with the stock radiator. More about that unfortunate discovery when I report on my track day at Pocono later this week.

-Bill

[RallyBob]

Originally Posted by shotgunslade

Saw Jack and his car at at Pocono today. Said he had dynoed the car at 300whp recently. Also said he is still having some overheating problems, despite having a 25 psi radiator cap. He confirmed that he is going for individual throttle bodies for each cylinder.

Bummer. How'd the car sound out on the track?

I also found out that a 20 psi radiator cap is incompatible with the stock radiator. More about that unfortunate discovery when I report on my track day at Pocono later this week.

That doesn't sound good either. I suspect the plastic yielded judging by your comment?

[TomsSVX]

yea he split the tank at their usual weak spot on the top. No worries an all aluminum PWR is on the way for his ol' girl

Tom

[Tim]

Originally Posted by TomsSVX

yea he split the tank at their usual weak spot on the top. No worries an all aluminum PWR is on the way for his ol' girl

Tom

Dan's car definitely deserves it . I'm surprised the stock radiator lasted that long with all those high speed runs at the track.

[shotgunslade]

Rally Bob:

Jack's car sounded great. I don't think I was on the track with him because I was in the Open Track sessions and I think he was in the Comp School. I couldn't get a ride because it's now a "proper race car" with only one seat.



Yes radiator split along the front side top between the hose connection and the cap nipple. Tried to KDWeld it, which lasted about 5 miles. Towed to Ertle Subaru in Stroudsberg. YT is UPS'ing up to their shop the radiator from his silver, which is down, and I'm buying a new one that will ulimately go back in the silver. They said they could install, but no warranty. I told them, "It's a track car, I'm just as likely to ask you for a waranty as I am to ask my insurance company for damage protection on the track."

Hopefully, I can pick it up on Saturday morning and drop by Reading on the way home. Obviously Lime Rock is out for that morning.

[RallyBob]

Originally Posted by shotgunslade

Rally Bob:

Jack's car sounded great. I don't think I was on the track with him because I was in the Open Track sessions and I think he was in the Comp School. I couldn't get a ride because it's now a "proper race car" with only one seat.

FWIW, I spoke to Jack yesterday, and while the car did fill the overflow initially, he said after that it never got above 180° on the track, and never lost power like it did in the past when overheating. Oil temps stayed constant as well for once, usually when the coolant temps rise the car's oil temps skyrocket as well.

Hopefully, I can pick it up on Saturday morning and drop by Reading on the way home. Obviously Lime Rock is out for that morning.

Well, if you ever get out to Lime Rock again, let me know. I live about 28 miles from there and wouldn't have to come up with any excuses to make a trip out there.