The Mule rides again (sort of) - pics.

[The Dark Side of Will]

I looked at Chris' lz9 fiero a while back, and he had HPT open, so I took a look at the tunable parameters, and it had a ton of stuff not pertinent to a pushrod V6, coupling that with the fact that there is one VDF on tunercat obd2 that covers the v6, the n*, and a few other engines, I suspect a clutch pedal position sensor will be desired.

Chris is in the process of adding a clutch pedal position sensor to his car now. He has run without one for a while, with just a few minor quirks. I'll ask him to send me pictures of how he mounted it up.

By the above, you mean that one TunerCat VDF covers all E67 applications?

Ryan says the '06 Pontiac G6 OS is nothing like the '06 NorthStar OS.

[ericjon262]

I can't speak for what Ryan can, or cannot see, all I know is that the same VDF is used for a bunch of applications including N*, LZ9, and LS4 I'm sure the calibrations, and flags for the individual engines are wildly different,

[The Dark Side of Will]

Also, I snagged a 3.91 F40 from a '03-'04 Saab late last year... it's been kicking around the back of my van in a tote for months and months. I finally verified the ratios and dropped it into "storage" next to my '09 Saab F40 with High Feature V6 bellhousing. My aim is to snag an '07 G6 F40 and merge it with the 3.91 F40 to build The Mule's eventual transmission. The '09 Saab trans will get married up to a LLT of LFX to be ready for... something. It has MU9 gearing, so I'd love to get an MT2 0.62 sixth for it.

I was surprised to find that it looks like this box has a Torsen or similar diff.

Circling back for a sec...
This thread mentions a factory Saab helical LSD... so apparently I lucked out in that this transmission has one. Sweeeeeet!

https://www.uksaabs.co.uk/UKS/viewtopic ... 94#p929894

[Honest Don]

Nice! That’s much easier for sure.

[The Dark Side of Will]

Put the coil pack together last weekend







Didn't get any pics of the bore in the adapter, but had the first iteration of the single plate throttle adapter cut
It still had serious clearance problems. The water manifold is *NOT* in place in this photo.





Got this measurement over to Eric, who confirmed that the 8 wire throttle actually has a larger dimension than the 6 wire unit, so I won't be able to switch to improve clearance.



And this measurement was a big PITA to get.

After evaluating the fit of this first iteration of the adapter, I'm pretty sure I can make it work this way, but not this revision. The bore in the manifold is 3.120" while the edge on the throttle is 3.030". The bore in the adapter is 3.030 to match the throttle. The bore in the adapter ended up tangent to the BOTTOM of the bore in the manifold, so I can move the adapter bore up until it is tangent at the TOP of the manifold bore. There wasn't really any room to move the throttle around on the adapter; I did a decent job getting that right the first time.

I ALSO noted that if I angle the 3.030" bore in the adapter such that the long axis of the resulting ellipse is 3.120" on the adapter surface, that angle is 14 degrees. Angling the bore to offset the throttle gives me another 0.90 in a 3/8" plate. I think between moving the bore up to tangency at the top of the manifold plate and angling it 14 degrees further up, I should have "plenty" of clearance to make everything work.

However, the bolt holes are overlapping awkwardly, so I need to put some more thought into how to deal with that.

I do need to test fit with the motor on top. That's the original orientation, so it's actually "right-side-up" that way. However, I need to counterbore the adapter plate and get (cut/make) shorter M6 screws in order to do that.

[The Dark Side of Will]

Pro/Con:

Motor on bottom (upside-down):
=>3/8" thick 14 degree angled bore adapter probably has enough clearance to the water manifold
=>3/8" thick 14 degree angled bore adapter has interfering bolt holes, but probably not enough metal in the throttle casting to slot to line up bolt holes
=>3/4" thick 14 degree angled bore adapter has different bolt hole interference. Will not be able to design out bolt hole interference in an angled bore adapter. It can *just* work in a straight adapter because both sets of lower bolt holes end up close.
=>Installation would look cleaner

Motor on top (right-side-up):
=>3/8" thick straight adapter probably has enough clearance to the water neck (need to verify)
=>For a straight adapter, bolt patterns are close enough that they can work.
=>If I line up the bottom of the throttle bore with the bottom of the manifold bore, I can align the lower pairs of bolt holes almost exactly.
=>Requires counterboring the adapter so the throttle clears the heads of the screws in the upper manifold holes

Other:
=>Odd angle with the electrical connector at the very top will almost certainly work
=>90 degree angle with the gearbox on top and motor toward the fuel rail may have enough clearance to the fuel rail to work as well


After eyeballing it today, I think I need to counterbore the prototype adapter so that I can check out the right-side-up mounting and verify that has clearance to the NorthStar water neck.

[The Dark Side of Will]

Figures I would get so far down this path than discover... another path.

The '06 FWD Northstar had an 96mm throttle... but RockAuto doesn't list that as being shared with anything. I sort of @$$umed it was shared with something and didn't think much more about it.

The LS4 has a 77mm throttle that's shared with the Atlas 5 cylinder engines and is a big-brother to the Cobalt SS Supercharged throttle

The '95-'99 Northstar manifold has a 79mm opening.

On a lark I checked out the '06 RWD Northstar throttle. Dammit, it's 80mm and a brand new GM Genuine unit is available for $80. LOL. It uses a different electrical connector and is built in the opposite hand from the LS4 throttle. That means that if I mount it motor down, then the gearbox would be on the opposite side. Unless it's exceptionally compact, I don't think I'd be able to mount it motor down, but mounting it motor UP should be easier than mounting the LS4 throttle motor up, as it wouldn't have interference between the water neck and gearbox.

[The Dark Side of Will]

The '06 FWD Northstar had an 96mm throttle... but RockAuto doesn't list that as being shared with anything. I sort of @$$umed it was shared with something and didn't think much more about it.

Looking a little more closely at the applications list... The RWD NorthStar cars (XLR, SRX, STS) had the 80mm throttle through 2006, then went to the 96mm throttle--with NO CHANGE of horsepower rating--from '07 through end of production.

[pmbrunelle]

Looking a little more closely at the applications list... The RWD NorthStar cars (XLR, SRX, STS) had the 80mm throttle through 2006, then went to the 96mm throttle--with NO CHANGE of horsepower rating--from '07 through end of production.

The newer cars might have the bigger throttle for standardization reasons, not because the smaller throttle was a bottleneck.

With the drive-by-wire, you can correct the on-off switch effect of an oversized throttle.

How do you know the minimum throttle size you need? Look at what is used on engines with similar power as your power goal for this project?

Do you plan on having a MAP sensor? That would tell you if you goofed on throttle sizing.

[ericjon262]

does the RWD N* TB bolt on?

[The Dark Side of Will]

The newer cars might have the bigger throttle for standardization reasons, not because the smaller throttle was a bottleneck.

With the drive-by-wire, you can correct the on-off switch effect of an oversized throttle.

How do you know the minimum throttle size you need? Look at what is used on engines with similar power as your power goal for this project?

Do you plan on having a MAP sensor? That would tell you if you goofed on throttle sizing.

Right, the bigger throttle was the same that the FWD Northstars were getting, so they used it on all NorthStars. That specific throttle was only used on Northstar apps, but the guts may have been used in a different housing in other apps.

I'm using the biggest throttle that will fit my manifold. My HP goal is 450+ with 288 cams and ported heads. I'd love to be able to run the 96mm throttle.

Yes, I should be running a MAP sensor.

does the RWD N* TB bolt on?

Not to the '95-'99 manifold, but it has a symmetrical bolt pattern and may bolt up to the LS4 throttle adapter.

[Shaun41178(2)]

I didnt know you ported your heads. Cool

[The Dark Side of Will]

I didnt know you ported your heads. Cool

I don't yet... I'll have to figure that one out. I was ready to drop the coin on CHRF's wildest cylinder head package, but went to check and they had closed.

I *DO* have a set of their 288 cams and redrilled sprockets on the shelf.

EDIT: Maybe these guys? http://www.bpeheads.com/northstar.htm

[ericjon262]

I didnt know you ported your heads. Cool

I don't yet... I'll have to figure that one out. I was ready to drop the coin on CHRF's wildest cylinder head package, but went to check and they had closed.

I *DO* have a set of their 288 cams and redrilled sprockets on the shelf.

EDIT: Maybe these guys? http://www.bpeheads.com/northstar.htm

are the heads a radical departure from other DOHC heads? I would think that a shop proficient at porting import heads would be able to make some improvements, obviously someone specializing in N* parts would be preferred, but that kind of shop is becoming non existent.

[The Dark Side of Will]

are the heads a radical departure from other DOHC heads? I would think that a shop proficient at porting import heads would be able to make some improvements, obviously someone specializing in N* parts would be preferred, but that kind of shop is becoming non existent.

They're a little weird in that the intake valve angle is fairly large, like ~26 degrees and the exhaust valve angle is quite shallow, like 7 degrees. This is a packaging compromise to narrow the width of the engine to fit in FWD engine bays. The valve angles give the chamber a weird shape. I have some ancient correspondence with Allen Cline on the matter, but here's a linkable version: https://www.eng-tips.com/viewthread.cfm?qid=149346

They can be ported so the flow bench number goes up, but if you don't get the tumble right, the mixture distribution goes to hell and the engine makes less power because it's far more sensitive to AFR.

Porting 2 valve heads is easier because you get some amount of swirl "automatically" due to the off-center intake valve.

[Shaun41178(2)]

Do it yourself. Just clean up the bowls from casting flash and what not, smooth the short side and call them done

[ericjon262]

Do it yourself. Just clean up the bowls from casting flash and what not, smooth the short side and call them done

Removing casting flash typically doesn't do anything, most modern castings have minimal flash out of the box. The N* heads may be different, but I wouldn't bet on it.

[pmbrunelle]

They can be ported so the flow bench number goes up, but if you don't get the tumble right, the mixture distribution goes to hell and the engine makes less power because it's far more sensitive to AFR.

Porting 2 valve heads is easier because you get some amount of swirl "automatically" due to the off-center intake valve.

You already have camshafts, so don't touch them for now (we do want to see this car run), but if you wanted to iterate at a later stage, I wonder if it would be worthwhile to try a camshaft with more lift on one intake valve than the other valve.

[The Dark Side of Will]

Do it yourself. Just clean up the bowls from casting flash and what not, smooth the short side and call them done

Removing casting flash typically doesn't do anything, most modern castings have minimal flash out of the box. The N* heads may be different, but I wouldn't bet on it.

"Porting" without a flow bench is just grinding. EDIT: And hoping. Grinding and hoping.

You already have camshafts, so don't touch them for now (we do want to see this car run), but if you wanted to iterate at a later stage, I wonder if it would be worthwhile to try a camshaft with more lift on one intake valve than the other valve.

Yeah, I'm not going to stop now to dive down the rabbit hole of ported heads. I'll play with the cams to find the powerband I like, and at some point get ported heads on it, but not now.

I've heard of people playing with different durations for each intake valve in an effort to induce swirl. David Vizard went so far as to test differential valve diameters (Google: "Polyquad chamber"). He claimed great results, but I haven't seen enough instances of its use to say it's great across the board. I would think that if it were that great, OEMs would be all over it since it's not much/any more expensive than factory CNC ports and such that they're already using.

[ericjon262]

"Porting" without a flow bench is just grinding. EDIT: And hoping. Grinding and hoping.

I think this was more or less the point I was trying to make.

You already have camshafts, so don't touch them for now (we do want to see this car run), but if you wanted to iterate at a later stage, I wonder if it would be worthwhile to try a camshaft with more lift on one intake valve than the other valve.

Yeah, I'm not going to stop now to dive down the rabbit hole of ported heads. I'll play with the cams to find the powerband I like, and at some point get ported heads on it, but not now.

I've heard of people playing with different durations for each intake valve in an effort to induce swirl. David Vizard went so far as to test differential valve diameters (Google: "Polyquad chamber"). He claimed great results, but I haven't seen enough instances of its use to say it's great across the board. I would think that if it were that great, OEMs would be all over it since it's not much/any more expensive than factory CNC ports and such that they're already using.

can you change cams with the engine in the car?