rallyruss Posted July 20, 2004 Share Posted July 20, 2004 It is a stock 1:1 rising rate and perhaps I have it to ported vac and it should be non-ported or vice versa (can't remember where I have it plumbed) If I remember correctly, the fpr uses vacuum to raise the flow rate. Also, if I remember correctly, ported vacuum raises consistantly with increasing engine speed, non ported raises then goes to pressure as boost kicks in? normaly when vacume is applied to the presure regulator it drops fuel pressure 5 to 10 psi when under no vac. or boost conditions it will rise to full pressure. plumbed to a manifold vac. source. this applies to my 87 fuel system and most other vehicles as well. hope it helps. you can test this at idle when hooked up to manifold vac. watch fuel pressure with it connected and then pull the hose off. it should jump higher. Link to comment Share on other sites More sharing options...
garner Posted July 20, 2004 Share Posted July 20, 2004 thanks rallyruss, that helps, as I obviously didn't understand. Just to make sure I do now: So under high vacuum, like engine braking, (higher revs, no throttle) the pressure drops, at no vac or under boost it rises back to normal pressure.. I'll test it as you explained and report back, I have a spare so I could just swap them and see what happens.... I imagine I can do a similar test to determine if the vac advance on the disty is working properly. I need one of those vac pump/guage type tester thingy, would be really handy right now.... garner Link to comment Share on other sites More sharing options...
Subarutex Posted July 20, 2004 Author Share Posted July 20, 2004 Ok... so given this information... when setting fuel pressure to stock settings, should I unplug the vac. reference on the regulator while the car is at idle? Then set the pressure. Once everything is all set, then plug the vac. reference back in? Or would leaving it plugged in work just as well? Thats the way I did it... Link to comment Share on other sites More sharing options...
WJM Posted July 21, 2004 Share Posted July 21, 2004 Do the first thing you said. swapped MAF's yet? Link to comment Share on other sites More sharing options...
rallyruss Posted July 21, 2004 Share Posted July 21, 2004 So under high vacuum, like engine braking, (higher revs, no throttle) the pressure drops, at no vac or under boost it rises back to normal pressure.. almost.. its under a vacume at idle as well correct? so this regulated or reduced pressure is the "normal" pressure value (got that tex?) do bit of testing with your gauge you will see what I mean. once you understand it you can use this on almost all cars. Link to comment Share on other sites More sharing options...
garner Posted July 21, 2004 Share Posted July 21, 2004 Ok found my problem, I don't know why it always takes me so long to test the obvious, but I finally let her idle and removed the vacuum advance, no change. Put a length o' tubing on it and sucked really hard, no change. Pulled the vac advance unit to test out of the disty, no action at all. This is most definately my problem as it would clearly explain why the lag. It would seem I was retarded (the motor actually) and experiencing lag until the mechanical/electrical advance kicks in. Now to find a working one to swap. The dealer has to order from Japan at the tune of 2 weeks and a bunch of $$ Will report back when I can get a good vac advance in there but I am very optimistic. garner Link to comment Share on other sites More sharing options...
rallyruss Posted July 21, 2004 Share Posted July 21, 2004 nice work. hope that does it for you. now I can get back to throwing my TDO4 on with confidence. Link to comment Share on other sites More sharing options...
garner Posted July 22, 2004 Share Posted July 22, 2004 report: borrowed a similar vac advance unit from mudrat, adapted it to fit (the puller arm was not the right length). Installed, re set timing, (right about 23.5 btdc) took test drive WOO HOOO, now we're talking. Not getting any of the lag between idle and 2000, much better throttle response, not hitting the faux boost cut I was hitting before. just a short drive, but when shifting into second after a good hard pull in first and get a little this things a monster!!! garner Link to comment Share on other sites More sharing options...
suberdave Posted July 25, 2004 Share Posted July 25, 2004 ok glad to hear im not the only one whth the fuel cut prob... Background. i have an 88 gl turbo wagon, wrx intercooler, stock trubo, at 11psi boost. before i had 1.5 inch PVC pipe between the IC and the Throtle body, everything worked fine, never cut fuel. last week i installed some mandrual bent 2 inch chrome pipe and moved the MAF sensor about 6 inches out from where it was. now i hit fuel cut at like 5psi boost in 2nd and 3rd gear. is it possable to have to good of air flow after the turbo? like it is flowing all kinds of air, but not really pressurizing anything? also what is the effect of moving the MAF? is there going to be some lag? is the MAF calculated for the proper distance from the intake? just some thoughts. maybe this will help, and comments will deffently help me. -=suberdave=- Link to comment Share on other sites More sharing options...
Warp3 Posted September 14, 2004 Share Posted September 14, 2004 Muhahhahahahahaha...ahem...sorry... It's actually a hybrid setup that I've never heard of being built before, so I want to see how it turns out before I divulge the details. I'll try not to keep you in suspense for too long...LOL Well, since I never went through with having the turbo built (I kinda put a hold on the RX project when I bought my Legacy Turbo), I'll divulge my hybrid plans. The plan was a ported/polished VF7 with a TD04 compressor wheel. According to Jerry (i.e. Deadbolt) the intake housing does have to be significantly modified, but the TD04 compressor wheel can be made to fit. While the flow wouldn't be quite as high as an actual TD04, it would spool a good bit faster, which would make it better for autocross. Link to comment Share on other sites More sharing options...
JWX Posted September 14, 2004 Share Posted September 14, 2004 how much was he going to charge for that? Link to comment Share on other sites More sharing options...
Warp3 Posted September 14, 2004 Share Posted September 14, 2004 how much was he going to charge for that? Well I was getting some very special pricing from him, so I have no idea what the cost would have been normally for that setup. You could email him and ask, though. I would imagine that standard price would be similar to his price for a regular port/polished VF7 + his standard $299 fee for compressor wheel upgrades (though it may be more, due to the extra machining involved). Link to comment Share on other sites More sharing options...
JWX Posted September 15, 2004 Share Posted September 15, 2004 holy mother of god 300+, no thank you to that. I'll have to make him my friend I guess .or just get the port and polish job done. Link to comment Share on other sites More sharing options...
mAJJJORD Posted September 16, 2004 Share Posted September 16, 2004 so are these 'delta' cams, ground for N/A use?? if so why do you use them on a turbo motor. also, does anyone know for sure if the jap spec cams are different to US. Link to comment Share on other sites More sharing options...
WJM Posted September 16, 2004 Share Posted September 16, 2004 so are these 'delta' cams, ground for N/A use?? if so why do you use them on a turbo motor. also, does anyone know for sure if the jap spec cams are different to US. An intersting note is that the carb and turbo cams for 85-86 are the SAME...and those cams pull way better than the 87 and up. I used those 260 cams in a SPFI engine...they are NOT for NA gains at all really. Turbo...better watch out!! THEY ARE FAST!!! I dont know of JDM spec cams....half to look around... Link to comment Share on other sites More sharing options...
DIRAVI Posted August 8, 2006 Share Posted August 8, 2006 ok glad to hear im not the only one whth the fuel cut prob... Background. i have an 88 gl turbo wagon, wrx intercooler, stock trubo, at 11psi boost. -Snip- is it possable to have to good of air flow after the turbo? like it is flowing all kinds of air, but not really pressurizing anything? -snip- It is possible, when you mount an IC, you get more air in at a lower boost. But it should not be that much! Link to comment Share on other sites More sharing options...
calebz Posted August 8, 2006 Share Posted August 8, 2006 Link to comment Share on other sites More sharing options...
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