Crazybassist Posted June 15, 2010 Share Posted June 15, 2010 Hi guys, I've just been under my car to fit a new 1bar RR to my Supra, as I was told it had been limited to 0.6bar by the previous owner, but when I got the old one out it looked identical to my new one. the boost gauge before was reading -0.6 to -0.7 at idle and went up to 0.6 when you gunned it. Is that normal? I seem to have a 2.5" pipe going to the backbox, which then goes up to nearly 4" and a 5" tail pipe. Having looked at the black ring of crud on the old ring I decided that the 2.5" down pipe was restrictive enough, so went for a spin without the RR fitted. It was pretty much the same as before but went up to 0.7bar. How the hell do you get 1.2 bar out of these things? Or am I already there and I have a dodgy boost gauge? Gonna put the RR back in just in case though. Ive attached a photo of the two restrictor rings so you can get an idea of the exhaust size. Quote Link to comment Share on other sites More sharing options...
wilson4347 Posted June 15, 2010 Share Posted June 15, 2010 Do you have a boost controller or just a boost gauge? Quote Link to comment Share on other sites More sharing options...
Crazybassist Posted June 15, 2010 Author Share Posted June 15, 2010 Do you have a boost controller or just a boost gauge? Just a boost gauge at the moment. I'm waiting for a mate of a mate to fit the controller. Will that up the boost? Quote Link to comment Share on other sites More sharing options...
James Posted June 15, 2010 Share Posted June 15, 2010 What other modifications have you had done? Fuel pump? Spark plug grade? 1st and/or 2nd decat? FCD? Quote Link to comment Share on other sites More sharing options...
Crazybassist Posted June 15, 2010 Author Share Posted June 15, 2010 What other modifications have you had done? Fuel pump? Spark plug grade? 1st and/or 2nd decat? FCD? It's supposed to have all those things done to it by the previous owner. I've only had it a couple of weeks and am just finishing what he started. Shame I know nothing about turbos eh!? Quote Link to comment Share on other sites More sharing options...
wilson4347 Posted June 15, 2010 Share Posted June 15, 2010 Read bpu and double check what the previous owner has done, and take it from there mate! Quote Link to comment Share on other sites More sharing options...
James Posted June 15, 2010 Share Posted June 15, 2010 Get it checked out as to what's done and what's needing done I have a FMIC, FCD, SLD, colder grade (grade 7) spark plugs, Walbro 255 uprated fuel pump, 1.2 bar RR and decat and an RS*R (aftermarket) exhaust. On my boost gauge I get stock boost levels. It'll jump up when I get the 1st (very restrictive) cat swapped for a decat. Nothing to worry about really, just need to have the right things done to see different results Quote Link to comment Share on other sites More sharing options...
Suprab1 Posted June 15, 2010 Share Posted June 15, 2010 Hi mate, i would think your exhaust is very restrictive. I have a 3 inch turbo back double decat & 6 inch exit from back box. When i took out my RR i was hitting boost cut very high up the revs. So i now have my RR with a 62mm hole & boosting at 1 bar. 1st thing is check all mods are done (as was already said) & get the boost double checked. If all is ok you could upgrade your exhaust or get a boost controler. I would prefer to upgrade the exhaust though as there would be less back pressure on the turbos. Quote Link to comment Share on other sites More sharing options...
Suprab1 Posted June 15, 2010 Share Posted June 15, 2010 Get it checked out as to what's done and what's needing done I have a FMIC, FCD, SLD, colder grade (grade 7) spark plugs, Walbro 255 uprated fuel pump, 1.2 bar RR and decat and an RS*R (aftermarket) exhaust. On my boost gauge I get stock boost levels. It'll jump up when I get the 1st (very restrictive) cat swapped for a decat. Nothing to worry about really, just need to have the right things done to see different results Why have you got a RR in when your 1st cat is in place? What size is your exhaust? I was getting 1 bar boost with my 1st cat still in. I wouldn't pay any attention to the bar rating on RRs. They will give different results in different cars. My 1 was supposed to be 1 bar but i only got .8 bar so i had to drill it bigger. This could be why your only getting stock boost. Quote Link to comment Share on other sites More sharing options...
Crazybassist Posted June 15, 2010 Author Share Posted June 15, 2010 Cheers guys. I've done some reading online and think I just need to fit the boost controller to get some more oomph out of her. I didn't know it played with the wastegate to get more boost. Shame I can't get it fitted before the drag racing on Saturday. Maybe for next months race Quote Link to comment Share on other sites More sharing options...
James Posted June 15, 2010 Share Posted June 15, 2010 Why have you got a RR in when your 1st cat is in place? What size is your exhaust? I was getting 1 bar boost with my 1st cat still in. I wouldn't pay any attention to the bar rating on RRs. They will give different results in different cars. My 1 was supposed to be 1 bar but i only got .8 bar so i had to drill it bigger. This could be why your only getting stock boost. I bought the car as is. It'll hit higher boost when I remove the 1st cat and it is then that I will find the restrictor ring serving any purpose. If I didn't have it -when the cat is removed - I'd spike moreso. Quote Link to comment Share on other sites More sharing options...
Suprab1 Posted June 16, 2010 Share Posted June 16, 2010 I bought the car as is. It'll hit higher boost when I remove the 1st cat and it is then that I will find the restrictor ring serving any purpose. If I didn't have it -when the cat is removed - I'd spike moreso. Ah right. Well in that case get your first cat out the power difference is class. When i took out my 1st cat & put in my RR it brought my boost back to stock. I couldn't believe the difference between .8 & 1 bar. Quote Link to comment Share on other sites More sharing options...
James Posted June 16, 2010 Share Posted June 16, 2010 I'll get to that soon certainly Will just need to watch as it's an NA-TT 5 speed I bought, so need to hope the W58 copes Quote Link to comment Share on other sites More sharing options...
Suprab1 Posted June 16, 2010 Share Posted June 16, 2010 I'll get to that soon certainly Will just need to watch as it's an NA-TT 5 speed I bought, so need to hope the W58 copes I've heard the 5 speed is good on a turbo. I'm sure it'll be fine. Quote Link to comment Share on other sites More sharing options...
James Posted June 16, 2010 Share Posted June 16, 2010 The ratios make it accelerate really quickly. It's good fun as is. Just need to get that cat out and dyno it. Quote Link to comment Share on other sites More sharing options...
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