| Re: Engine rebuild/upgrade project |
Subject: Re: Engine rebuild/upgrade project by sliding on 2010/7/5 10:28:48 Thanks Pete! I've installed it straigt up (lined up the dots) and then rechecked it with degree wheel and dial gauge to see if everything is within the specs. I'm a little behind with posting and pics. The engine is allready in the car and I've fired it. I had some trans problems but I've sorted that out. Right now, Mick (mseven) and I are trying to get the tune right. I'm having some idle issues. Engine is running waaay too rich at idle. Right now I'm waiting for a new O2 sensor to come, as mine is not in the best condition. I've started a thread on another forum but I won't start a new one here, I'll just C/P from there: C/P In short here are engine specs - 2bolt block, overbored 0.020" - stock crank - SCAT forged rods 5.7" - SRP forged pistons, flat-top - #113 heads, ported, 2.02/1.60 valves - ported superram - #24 FMS injectors - Hooker LT headers - CC XR288HR cam, 288/294 adv., 236/242 @.050", .55"/.57" lift, 110 LSA I'm having my tune done by Mick (mseven). Engine fired right up with his first tune but it was running rough and very rich. From datalogs, we have noticed that vacuum is low (70+ kPa). So I tried to find if there are any vacuum leaks or other mechanical problems. I did find some issues, but I sorted them out and I still have the same problems. Problems are next: When I start the engine it runs stable but very rich. WBO2 is showing high 11 to low 12AFR and considering the size of the cam and overlap, I think that it's even more rich than that. As the engine is heating up the problems start. Engine wants to stall and sometimes it stalls if I don't blip a throttle. Idle starts to go up and down all the time. IAC ccounts are allways going down. From the moment when I start the engine IAC counts are slowly going down, until they finally reach zero. If I adjust the throttle screw I can get them to raise, but again, as the engine is running IAC starts to drop. Map signal is acting very similar. As I start the engine, it's stable at lower 70's but as the problems with stalling start, MAP starts to jump all over the place. I guess that it's normal that it jumps to 90 because engine almost stalls. All the time there is way too much fuel as I can see it smoke and it really burns the eyes. If I start to drive, WBO2 starts to show 14.5-15 AFR and the smoking stops. But as soon as I stop and the engine starts to idle, AFR gets really rich. As for vacuums, I have plugged everything except MAP, fuel regulator and PCV hoses. I have tried to plug the TB with engine running and listen for any vacuum leaks but I can't hear anything. Any inputs and ideas are welcome! |
