MaTTSuN Posted April 12, 2011 Share Posted April 12, 2011 Well the time has come to do a head gasket since it weeps a little oil and to get all the other oil leaks taken care of. I have an 78 l28 n/a that i look out of the car and was thinking about putting the cam into my 81 L28T engine I am running the stock turbo for now, but have a megasquirt & spark,bigger injectors and a FMIC im looking for a little more out of this set up, would the n/a cam be a step in the right direction? I am going to do some autoXing and some track events as well as daily driving thanks Matt Quote Link to comment Share on other sites More sharing options...
BluDestiny Posted April 12, 2011 Share Posted April 12, 2011 What kind of power are you making with those mods right now? and how much more do you think you would gain with a slightly more agressive cam that can't be fixed with a few more PSI? Quote Link to comment Share on other sites More sharing options...
MaTTSuN Posted April 12, 2011 Author Share Posted April 12, 2011 im running about 8 or 9 psi now i think about 220 to the wheel, im looking for a smoother power delivery and a little more revs my power window is too small now its like an on/off switch about 3000-5000rpm it makes great power then hits a wall. Id like to have 300@ the wheel i have all the parts so its not much more effort to put it all together just want to figure out if that cam would make the engine behave like i want i have 340cc injectors so 300-320 should be my target power and still be safe Thanks Matt What kind of power are you making with those mods right now? and how much more do you think you would gain with a slightly more agressive cam that can't be fixed with a few more PSI? Quote Link to comment Share on other sites More sharing options...
Tony D Posted April 14, 2011 Share Posted April 14, 2011 (edited) 1) You are driving the car incorrectly: gear it so you are in the power band on-course. You should not be below 3000 rpms. Same as a Cammed engine. 2) Use a smaller turbine wheel A/R like a 0.48 instead of the 0.63. Mine would spool off-idle to 17psi at 1700 rpms and driving autox was a breeze. Everybody goes for terminal power numbers under some misguided assumption that a small housing just kills your 'top end' horsepower, which especially in stock turbos is hogwash---run a smaller A/R and get the spool back to where it was stock, or slightly lower. It will work wonders coming off a corner. 3) when you change to the smaller A/R, install an ATB, or LSD. You will burn the tires with all the torque you have. STaying in second gear will not be an issue and people will be amazed at how the car squats and goes. You don't need a cam to run the power up higher, you have a terribly mismatched turbo for the application. If it's not boosting to 9posi until 3K rpms, you have a serious mismatch on the turbo or severe tuning issues which should manifest in a number of other ways which I would think you would mention...so that leaves bad turbo selection as the most likely cluprit. Even with the smaller housing, the thing can be cut, and a slightly more agressive cam can be added to push power peak up a bit higher, and give the sensation of pulling to 6000+, instead of 'wow if I short shift at 5500 this thing sure seems faster' type of run you are likely getting now. Been here, solved that. With the original 0.48 nissan housing suitably modified for the wheel and hybridized compressor 275-350 at the wheel with 17psi-21psi available at 1700-6500 was possible (though it was best shifted aroudn 6200 actually but would 'pull' to 6500 if asked on a long straight.) 21 psi was really close to the surge line and was touchy on a hot day... or really cold day. But at 17psi the car was so strong and strong down low it was not a necessity to go to 21. I would routinely cruise in top gear at 50mph and 2K rpm, and just hammer the throttle to pass people. The torque was amazing. I miss that little turbo, and lament I ever drank the cool-aid and put the US Market 0.63 housing turbo on the car. I should never have sold it to that damnable Isuzu freak with the Impulse/Imprezza... Edited April 14, 2011 by Tony D Quote Link to comment Share on other sites More sharing options...
Pyro Posted April 22, 2011 Share Posted April 22, 2011 A few weeks ago I pulled out my msa stage 1 turbo cam and went back to a stock NA cam. My engine pulls hard to 6000 then falls off. It will make 6500 in first and second if I'm slow to shift. Stock turbo cams stop pulling around 5200. You should be boosting sooner with the stock 0.63 turbine. Maybe you have something wrong with the tune or the turbo. Full boost by 2700 should be about normal. 8 or 9 psi with a stock engine and IC should be about 200 to 210hp. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.