white924s

As some of you may recall, I recently acquired a second intake manifold to powdercoat and install in my engine. I thought thatall N/A intake manifolds were the same, but apparently not...according to my mechanic, it turns out that the Idle Stabiliser Valve hose doesn't fit well with the early intake manifold. Has anybody else run into this problem?

If so, how did you get around it? Can I just delete the ISV or will that have a profoundly negative impact on my engine's ability to run well? Alternatively, can the Auxiliary air valve system from the early cars be fitted to a 924S (which I believe has the late ISV system)?

Thanks!

edit: PICS ADDED BELOW

white924s

On a positive note, however, they did say that the Lindsey fuel rail went on smoothly, so hopefully I'll soon have some sweet pictures to show!

eman930

Cant say I have run into this problem, I think they are all the same, Its a very tight fit anyway.

white924s

hmm...yeah its definitely a new one by me. Some more research of parts catalogs shows me that there are two different part numbers. I don't have either manifold in front of me, so I don't know exactly what the difference is. Right now, I'm leaning towards getting the original manifold powdercoated - I think it'll be cheaper to do that and sell the early manifold than try to hack something together to fit in the space.

I will use this thread to post updates on the project though so that I can hopefully add a little to the archives - in case anyone else needs to figure out early vs. late N/A manifolds

eman930

What was the reason for swapping to a early manifold?? Its good to see that some one else is doing alot of mods to their 924S also. Keep up the good work, And post pics soon

eman930

HEy, Also if you could give me some info on the fuel rail your using that would be great, I have been eyeing the LR one, But my 924S fuel lines come from the Driver side Not the Pass. side and it looks to me the LR fuel rail only mounts to the Pass. side fuel lines, what did you do to solve the problem

white924s

to be honest, I didn't realize until today that there was any difference in intake manifolds. I got a second intake so that I could powdercoat it and put on the car (then later powdercoat the old one and hopefully sell it to offset the cost). So I can't say that there was any reason per se, except that I didn't read the parts catalog perhaps as closely as I should have...learn something new I guess

I'll definitely post some pics when I can - hopefully later this week. I used the Lindsey Racing rail and bought my own lines. I used www.anplumbing.com and www.summitracing.com for all the hydraulic parts - aside from the compression fittings (which I got from LR) everything else is just standard AN -6 or 3/8" NPT, so generic race parts shops will have them. My mechanic did say that some extra fittings were needed beyond what I purchased, so when I pick the car up I will report on what he said. He did say that they got it working though (save for the idle problem...), so that's a relief.

M758

Make the hose fit...
It is just a vacuum hose so just clamp it to work. It will be alot harder to use the old idle system as the electrical connectors are different. Running without the idle stalbization is not good for a street car. The car won't idle well cold or with the A/C. Track only cars are probably ok.

white924s

OK - so I went to see the car today. On the plus side, the Lindsey Racing fuel rail looks amazing with the powdercoated manifold. The new brake booster, master cylinder, and overflow tanks really make the engine bay look much better (it could still use a thorough cleaning and some touchup paint, but its an improvement, trust me!). I used Pro-Lite hydraulic line from Earl's - it's just as good as stainless braided, but it's not abrasive so I don't need to worry about it destroying anything in the engine. And I think it looks pretty sharp with the other black accents in the engine bay (personal opinion - stainless braid looks sharp too)

On the negative side though, I'm really not happy with what they did with the hydraulic lines, and there's the idle problem too - I think its definitely the ISV because it doesn't sound bad above idle, but when cold, startup sounds awful.

I think I can see what the difference between the early and late manifolds is - the fitting at the back of the manifold moved 90 degrees (unfortunately no before/after pics right now). With the hydraulic lines, I assumed that they would cut the hard lines and use the compression fittings I provided, but I guess not...I'm going to talk with them about that tomorrow because putting clamps on the pressurized lines like that scares me (although not as much as clamping stainless lines would, but still...)



a bit closer up



Check out my new brake booster/master cylinder/reservoir



And lastly, close-up on the fuel pressure gauge...I think it might be reading a little low, but I suspect that that is related to the idle problem

white924s

And, given the relatively cheap price of powdercoating, I think that I will powdercoat the original manifold and sell the powdercoated early style manifold (FS thread for that soon). It's pretty cramped under the manifold so I think that rather than trying to jury-rig something (it's a street driven car with AC, so it sounds like just deleting the ISV is off the table, and I don't know how much I want to get involved with squeezing silicone hose into that space). I'll just go with the factory setup (and probably replace the rubber hoses at the same time - at $10 a pop, I think I'd prefer to be sure that I have quality pieces in there so we can hopefully move past this idle problem).

In related news, I also have a Lindsey vacuum line kit that I'll be putting in as soon as I get this and my body work (euro bumpers and possibly full respray) done.

eman930

WOW, The lindsey Rail looks SWEEEETTT, So does that intake manifold. Mind giving a link for the summit stuff?? I had a idle problem when I first got my car, It was the ICV, They crap out sometimes when they get old. Really looks nice, Keep up the good work. When Mines done I will have to drive up there and visit, My dad Manages the Hydro plants up in NH, Havent been up but I hear that there is some GREAT roads

white924s

Thanks! I'm really happy with how the rail and manifold came out. Eventually I think I'll have to get the Lindsey blue plug wires and harness replacement to finish the look (and a cleaned up head underneath too), but one step at a time, right?

I've been reading/searching the archives here and it does look like ISV failure is not uncommon on these cars, so it wouldn't surprise me...the mechanic said he thought it was that, and I buy it too based on what I saw/heard today.

there are definitely some great roads around my area in NH - lots of scenic drives and some fun twisties haha.

moorepower

Niiice!

Now get in there and do some detailing!

Will Feather

looks great! We should have a meet someday all the Ma, RI, NH guys

white924s

Thanks for the kind words! As soon as the bodywork and engine repairs get wrapped up, I would definitely love to do some detailing and a meet up of some sort.

I'll warn you all though, it may be a little while for me though - I have a very bad habit of constantly wanting to fix something on this car haha