legacycentral bbs

So I got a boost gauge from Pep-boys today. Not a permanant gauge, just a temp one to hold me over until I can get my Stewart Warner gauge.

I T'd it into the #1 cylinder and sealed it up.

Did a pull, the gauge pulled right to just under 9psi, so it works.

But the vaccum seems to be unstable. After a rev, it'll drop to -22 and then bounce up to 17 and hold there.

Hood open, and a blip at the throttle you can hear a slight woosh of air as it rev's down. Even if you don't go over 1200rpm's, woosh. Vaccum drops then levels out.

My boost gauge is rigged SUPER ghetto setup, but there is no fluctuation at idle (except after a throttle blip) and on a pull, boost is stable. I don't think the gauge is causing a problem, but it did help me notice it.

Could this be a reason for my dancing idle (dipping to around 600 and fluxing between 600 and 750, visible needle movement)?

Another thing I noticed while testing the gauge. In 2nd gear and WOT, it seems like the car would hit a wall at 5000 RPM's. The tach would stop moving, it wouldn't be pulling really to hard but the gauge would be pegged right below 9psi.

Since I can't exactly get the car on the road, I don't know if it is just the conditions but WOT in 2nd gear, and it seemed like it hit a wall. Could this be because of a leak?

Last thing: What are your guy's VAC readings at idle?

A dancing idle can cause fluctuating vacuum, just as fluctuating vacuum can cause a dancing idle.

You say manifold vacuum is unstable but also that there is no fluctuation at idle. I'm confused by that.

You normally get the highest vacuum when the throttle is closed at high RPM. As the engine coasts down to idle speed it pulls a harder vacuum. So if you get 22 inches while the engine coasts and then 17 at idle, that's about what you should expect. My engine does that except I get closer to 19 at idle.

If you think you might have a leak, break out a can of starting fluid and look for it. Vacuum leaks, dirty IAC valves, and screwed up fuel trims are all possible causes of unstable idles.

Awesome man! Thanks!

What about the 5000RPM wall? Any insight?

I dunno; it's hard to say. It could be misfire; have you tuned your car up? It could also be a fuel cut of some kind. What changes did you make right before it started happening?

vrg3 wrote:As the engine coasts down to idle speed it pulls a harder vacuum. So if you get 22 inches while the engine coasts and then 17 at idle, that's about what you should expect. My engine does that except I get closer to 19 at idle.

Not that you need it, but I can confirm this.

Installed boost gauge today. Idle at slightly less than 19 inches. Off throttle coasting pulls about 22-23 inches. Boost holds steady at the expected 8.5+ lbs. Tapped at the typical point on manifold over cyl. #1.

By the way-- Autometer Z Series 2601 (30 inches vac. <--0--> 20 lbs. boost) mounted in 2204 cup on steering column.

I got a $14.99 special at Pep-Boys. Sunpro Boost 30" VAC - 0 - 20psi. Apparently it's pretty much dead on. Reads perfect boost, but seems to be slightly high on the VAC (16" instead of the expected 19")

Ain't pretty but it does the job. Designed for hillbilly pickups I'd rekon. Ghetto rigged in there. It'll do me until I can get my Stewart Warner gauge (30" VAC - 0- 15psi).

Turbocharged hillbilly pickups?

I think they're targeted at ricers.

$14.99's a good price! How large is the gauge?

14.99 is a good price. I may pick up something similar at WalMart to see if what my fancy shmancy AutoMeter is telling me is right.

Supercharged hillbilly pickups. I live near Frederick, remember?

It's a 2" gauge, mechanical. It takes a bit of creativity to get it to work right, but it does work.

Hehe, oh yeah.

What kind of work did it take to make it work right?

A $2.99 trip to Home Depot and a $.89 T-splicer.

5/16" ID clear hose ($2.99 for 20'. I have all 20' running to the interior, I didn't pass it through the firewall, just through the door)

Electrical tape and hose clamps to clamp the 5/16" hose to the stock crappy hose (it's some plastic stuff that is TERRIBLE to use. It's way to brittle to use for ANY period of time).

It works properly and seems to be dead on.

I'll actually be selling the whole setup for cheap if you wan't it. I'm getting my Stewart Warner Boost gauge and CRX pod this friday (along with my custom welded Stainless Steel IC pipe)

Ah, cool.

I may want it... It'd be cool to use with my current manifold pressure gauge to measure intercooler pressure drop and stuff like that.

Cool deal. I'll trade you the gauge (with stuff) for help installing my new clutch line (and maybe a brake lesson, lol). It'll be a few days though, seeing as I gotta get my S/W gauge first.

When will you be back down in the DC Metro Area?

Heh, that sounds cool. The clutch line will be super easy to install; brake work takes a little longer but is still straighforward.

It looks like I'll be carrying one carload of crap from Ithaca to DC sometime early in May. I'll probably make another trip shortly afterwards to bring another carload.

Where can I rent a trailer cheaply?

Uhaul is really cheap (like $19.99 a day or something).

Budget has CHEAP trucks (like 40 bucks a day), but not trailers.

May is good, I should have the car on the road in May (maybe... ok, bad joke, moving on.)

Even if I don't I can still do the clutch stuff. I need change ALL the fluids in the whole car one of these days.

Ya, brakes are really easy, as long as you have the right tools. Even taking it slow and easy, I can change my rotors and pads in about an hour.

A small trailer from U-haul is actually really cheap. Might be worth checking out.

Are you going to be stopping for any visits during your move Vikash?

Matt - You gotta get down here over the summer and start hangin out man! The car has changed a LOT since you and Vikash saw it last.

Kinda pissed that my whole IC install has cost me $100 now, but it works and I want to do it right.

Well, once you're done with school I'm sure we will. I'm down there every week, just not the same time as you.

I can't wait to see the 94. Hopefully it WILL be on the road by then, hmmm? Lol.

$100 is a bit more then I ended up paying in total but that's still not bad for an installed TMIC setup. what made it go over budget?

$40 for the pipe. Stainless Steel, angled bung, sand blasted for a uniform look. It's all about looking factory. Brought me to $90 for the IC and the pipe, and $14 for the radiator hose, and then $6 for 2 connectors and $5 for the third connector.

Worth it? Cheaper than my alternatives, and it looks bone stock. It does what I need it to do, and it should do it fairly well.

Speaking of which, if anyone wants an all aluminum IC, let me know and I might be able to oblidge. The shop where I got mine has a rack of them.

BAC5.2 wrote: Speaking of which, if anyone wants an all aluminum IC, let me know and I might be able to oblidge. The shop where I got mine has a rack of them.

Would you be referring to a Saab 900 IC?

That, sir, would be correct. All Aluminum Saab 900 IC.

Thanks for the advice guys; I'll check with U-haul. The catch is that I'd either need to make it a 1-way rental or have the rental span a couple of days. I know 1-way rentals are really expensive but they don't have rates for more than 24 hours on their web site.

Matt, I don't know if I'll be able to stop too long, but if I can, I will. I'll let you know when the dates are figured out so we can see what to do. Even if we can't meet up in Williamsport maybe we can meet up in DC.

Haha, Phil's gonna be a Saab 900 I/C vendor!

Ok Phil, I've tried to be patient.....WHERE ARE THE PICS!!!

Vikash, right on. I'm sure we'll meet up one way or another.

I gotta get back to school first!

Pics!

All it's missing is the pipe. That clear hose is for my GHETTO boost gauge.

Weird thing happened today. Everything stabalized. My idle was rock solid at 750rpm's after it was warmed up. Vac was reading just below 19". It pulled cleanly to 6k in 2nd gear (and pulled nice and hard too).

Weird huh? I didn't change anything except put it back to stock.

Anyway, to appease Matt and the rest of you guys...



Note the Coffee Mug. Keep it fast and keep it flat black. I need to do another coat on it and then some clear coat. The High-Temp Exhaust manifold paint I used is surprisingly crappy in terms of durability. That's 3 coats, and you could scratch it off with your finger nail (after it had been drying for 72 hours).



In this shot, you can see the clearance against the coolant tank. There is no stress on any of the lines or anything. I seem to have more clearance than you do Matt. IIRC, your IC was resting ON the nipples. Mine rests on the Clutch resivoir top and Firewall.



Ghetto Fab setup. 20 feet of 5/16" clear tube (from Home Depot) and some electrical tape and hose clamps to hook it up to that puss ass stock line. Works dead on though (19" VAC, 8.7psi boost)