The Definitive "VVT swap into 90-97 chassis" Megathread.
#642
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So because there are 33 pages and I will probably find my answer right after asking I will ask for the sake of sanity. I just installed my 99-00 rail with my upside down 90-93 regulator. I have an issue where the 90 chassis didn't use disconnects on the fuel hoses. Does anyone have reccomendations on how to cleanly or easily make that swap? Did you just put new hoses over the weird lock fitting from the fuel rail?
Thanks!
Thanks!
#644
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The OE plastic NB fuel line fittings that press into the plastic (nylon?) stock fuel lines do not have the correct style barb for generic rubber fuel hose. Depending on the type of hose you use and how much you clamp it down, they may cut through the inner wall of the hose. I believe @codrus had to deal this back when he was defuckulating the fuel system that had been installed by the PO of his Lowcost. I'd imagine he can weigh in on that one.
#645
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I realized that when I started messing around with it. I tried shoving the hose over the barb but there is no way I could non-destructively get it back off. I am not sure I want to risk running a strong clamp on it since the pressure inside the system is so high. Is there a cheapo way to flair the rail fitting?
#646
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I realized that when I started messing around with it. I tried shoving the hose over the barb but there is no way I could non-destructively get it back off. I am not sure I want to risk running a strong clamp on it since the pressure inside the system is so high. Is there a cheapo way to flair the rail fitting?
1) Push the hose on the end of the metal line with no barb, put a worm gear clamp on loosely, and embrace flaming death.
2) get a stock fuel line and very very carefully slice the nylon line off the quick-disconnect-to-hose-barb without damaging the plastic barb part. Push a rubber 65-psi-rated fuel injection hose over the barb and put a proper fuel injector hose clamp on it. This is what FM's instructions for the original 99 FM2 kit said to do (the one with the Link piggyback computer and 4 extra injectors).
3) **** that and buy a Dorman nylon line repair part ($12 for a pack of 2) instead of trying to salvage an OEM one. Do the same thing with the proper hose and clamp.
4) Get an all-metal quick-disconnect-to-AN fitting and put a bunch of other fancy AN fuel parts in your car. Like this: (note that there are fittings like this that use plastic locking inserts that are somewhat notorious for failing. get the all-metal one).
Somewhere in the middle is flaring the OEM line for an AN fitting. It's not really the right diameter (metric instead of SAE) and the steel is pretty hard. I'm not really a fan of it.
I have done 2, 3, and 4 in the past. Right now my car has #3 on it.
--Ian
#647
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3) **** that and buy a Dorman nylon line repair part ($12 for a pack of 2) instead of trying to salvage an OEM one. Do the same thing with the proper hose and clamp. https://www.amazon.com/gp/product/B000E35WHO/
--Ian
--Ian
#649
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I'm hoping someone can help with a sanity check since I couldn't find any ITB info in the thread.
I've got a '96 motor with Jenvey ITBs on it and Jenvey sells the NB manifold separately. So I should be able to swap the whole setup over. If I do that, I don't need to mess with the throttle body, throttle cable, TPS, or anything from the fuel system. The only things that need changing are the alternator, coils, CAS, and VVT control or am I missing something?
I've got a '96 motor with Jenvey ITBs on it and Jenvey sells the NB manifold separately. So I should be able to swap the whole setup over. If I do that, I don't need to mess with the throttle body, throttle cable, TPS, or anything from the fuel system. The only things that need changing are the alternator, coils, CAS, and VVT control or am I missing something?
#650
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You'll keep your '96 alternator, wire the VVT coils, split your CAS wiring to the CMP and CKP, and add the VVT system, yes.
Typically there is interference issues fitting an NA TPS on an NB head, but that's because of the intake manifold design. It should fit the head just fine, same with throttle cable.
Typically there is interference issues fitting an NA TPS on an NB head, but that's because of the intake manifold design. It should fit the head just fine, same with throttle cable.
#652
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Thanks to all for the contributions to this thread, and for Rev answering some emails about my MS3 Basic.. Have a VVT motor dropped in the car and I think I have the wiring done. I'm trying to figure out how to route the fuel lines from the fuel rail and FPR to the hard lines. Flat top manifold. Anyone have a picture or sketch of how they routed the lines?
I currently have the line from the FPR running under the plenum and down through a gap in the manifold but the line to the rail that connects to the FPR sticking straight up is stumping me.
I currently have the line from the FPR running under the plenum and down through a gap in the manifold but the line to the rail that connects to the FPR sticking straight up is stumping me.
#655
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I have mine setup in a similar fashion, but ran the fuel line tighter to the manifold, and down behind the throttle linkage. Not sure if that would work on a stock TB. I added an extra layer of hose for protection, but haven't noticed any evidence that the hood rubs on it. 5 years on the track with this setup and no issues. Ignore the arrows in the 2nd pic... was pointing out vac lines to someone in another thread.
![](https://live.staticflickr.com/65535/50849954947_754488e20e_c.jpg)
![](https://live.staticflickr.com/65535/50849954947_754488e20e_c.jpg)
![](https://live.staticflickr.com/65535/51935414366_169db8d47e_c.jpg)