Page 1 of 5 12345 LastLast
Results 1 to 20 of 99

Thread: Mpfi intake swap vortec 5.7

  1. #1
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469

    Mpfi intake swap vortec 5.7 (UPDATE) PICS ADDED

    As the title states i'm in the middle of swapping from the stock intake with internal poppet injectors. the intake i'm swapping to is the edelbrock 29135. installation went great fitment was much better than expected. where i'm going with this is the tuning side of it, iv'e adjusted my injector data for the oem gm 6.0 injectors but am a little hesitant to go messing with my transients. could anyone offer any advice. The setup is a 0411 pcm swapped 97 silverado, 5.7 vortec nv3500 manual trans. 3.42 gears 5.7 vortec Truck tune 90 OCT intake swap starter tune no ltft Maf.hpt Here is a tune file i copy and pasted a lot of injector and transient parameters into. I'm aware this is lightly charted territory here but maybe someone can offer some advice.
    Last edited by Oleblu; 01-31-2018 at 10:31 AM.

  2. #2
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    UPDATE!! I got the truck running tonight. Tomorrow I will begin SD idle tuning. I'm thinking I will have some transient issues anything more than slowly rolling into the throttle instantly pegs my afr guage lean
    Last edited by Oleblu; 01-14-2017 at 01:50 PM.

  3. #3
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    I was able to get out and do some tuning today. shit weather today but the Idle tune went quickly and moved right into OL VE tuning. after a few copy and pastes with AFR err i got most the low, medium load areas within -5-8% kept the high load areas pretty fat still untill a better day to tune i do still have a noticeable lean tip in which im feeling is transient related. ill keep poking at that but so far im very pleased with the swap. my powerband has been raised noticeably with the stock intake my cyl air readings started to fall off around 4700 now they're staying constant until 5400 was the highest i revved it to. when i get a decent log ill post it the wet weather is just making it difficult to get any decent wot data. I already put the truck back in closed loop gonna start tuning part throttle fuel trims tomorrow weather permitting.

    ole blue 90 OCT intake swap SDCL tune 2 smooth ve.hpt

    Here is the current tune
    Last edited by Oleblu; 01-14-2017 at 02:26 PM.

  4. #4
    Good deal man. Gona be a few months before I ever get to tune on mine.
    2001 Jimmy ,L31 with marine intake,CPC conversion,Nv3500 5 speed,SAS,Dana 44's front and rear,4.30 gears..

  5. #5
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    Another update spent some time between work today tuning the truck. Definite pro's and cons of switching to such a tall single plane intake. The Cons 1. low end torque loss I knew it was coming. But damn i miss it, probably honestly lost atleast 25lbft of torque under 2600 rpm. 2. I dont like the way the injectors sit in their boss. 3. I definitely have some transient fuel issues. an excessive lean part throttle tip in, accompanied by a rich off throttle coastdown condition. 4. A moderate amount of fab work went into this swap. pm me for anyone who is interested in finer details of the fab work. pro's 1. I finally have multi port fuel injection. 2. The engine is much happier and seemingly healthier above 3200 rpm. According to my butt dyno that is. 3. I'm finally ready to take it all apart again and install the ls6 springs on my vortec heads. Finally after all that work long tube headers a custom built 3" y pipe. with full single 3" exhaust and an intake swap. I feel like i'm ready to throw a cam in this thing.

  6. #6
    I donr the LS6 springs and 1.6 roller tip rockers on mine while I had it apart. Cam is my next upgrade down the road. Sound like we running close to the same motor except intakes. Im also running the CPC conversion.

    When I had mine running with just the CPC conversion throttle response seemed alot quicker and idle alot better.
    2001 Jimmy ,L31 with marine intake,CPC conversion,Nv3500 5 speed,SAS,Dana 44's front and rear,4.30 gears..

  7. #7
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    I long ago considered the cpc swap. but I really don't feel like I'll have ignition issues under 6500 rpm I could be wrong. they are similar setup but you seem to be going down midrange 4x4 road and I'm headed to the drag strip. which cam are you considering. I've got my eyes set on the 08-305-8 from comps efi friendly grinds.

  8. #8
    Im gona take mine to the drag strip to. LOL. We only have 1/8 mile track local. Figured Id go make a few passes for shits and giggles..

    I was going to run the Ram Jet 350 cam. Basically mimic the Ram Jet without the fancy intake. They made 350hp @5200 and 400ft/lb of torgue @3500. Should be more than enough in my blazer. A stock motor was plenty. But who wants stock. LOL

    Goal is to try to squeeze 350hp+ out of it with minor mods.
    2001 Jimmy ,L31 with marine intake,CPC conversion,Nv3500 5 speed,SAS,Dana 44's front and rear,4.30 gears..

  9. #9
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    Hell yea a jimmy at the track i like the way that sounds. i might be thinking a bit wishful but im expecting 375+ at the flywheel. This will be with the fel pro 1094 head gasket .015 compressed, the heads straight milled .030 should put the chambers just at 59-60cc. the cam specs out at 220/230 @.050 276/290 advertised. lift is advertised @ .510/.510 with 1.5rr, an lsa of 114 with a icl of 110. The valve events pleased me compared to the notorious cc503 grind as most call it. but the overlap is within .5* i'm assuming to make peak tq around 4300 probably rev it to 6100 on occasion. with a static compression ratio just under 10.2 the dynamic compression calculators were coming up just over 7.90 hopefully this makes for a happy on 90 oct setup. Edit back on subject what i was going to post a few minutes ago is that i still have a lean tip in issue. im just about happy with my ve table now and I dont believe tuning it deeper into the negative trims will help this issue. Iv'e read about transients and understand what they are. now comprehending what they do and how they effect part throttle im obviously a little slow on. If anyone at all can help me understand a little more about how transients cause tip in and coast down issues. Id'e be a very happy camper.
    Last edited by Oleblu; 01-17-2017 at 08:08 PM.

  10. #10
    I was going to run a ZZ4 cam. Most guys run a LT4 hotcam. Both give up low end torque. trying to keep from losing any torque. Its what I need more than hp. Motor should have plenty of power to surprise a few more cars from stop light to stop light.

    I wouldnt think it would be that hard to get damn near 400 at the flywheel. Have a look at this thread from GM Performance.. Guy done a dual plane marine intake. Jad the same issue your having with transient fueling. Might give ya a little help.

    http://www.pacificp.com/forum/viewto...er=asc&start=0
    2001 Jimmy ,L31 with marine intake,CPC conversion,Nv3500 5 speed,SAS,Dana 44's front and rear,4.30 gears..

  11. #11
    Don`t mean to jump into your thread,but that cam you picked (CC 08-305-8)will not help your low end torque problem. It has too much intake duration. Anytime the @.05 intake duration is close to or over 220*, you will loose intake vacuum and low end torque.You should stay nearer to 210*.One of these CC cams or similar would be a better choice,IMO.CC 08-465-8,08-412-8. Also a dual plane (marine)intake is also needed for low end torque.

  12. #12
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    No problem at all earwax. By all means speak freely I'm aware my cam choice is borderline to large. And I will sacrifice vaccum but I'm looking to make peak power at 5700-5800 and shift around 6000-6100. I understand my truck is heavy (4500lb with me) and it's a bitch to get moving. But my left foot slipping off the clutch pedal at 3500 rpm with a sticky set of tires should get my fat ass moving out or sideways. Yes ill probably be changing a clutch at some point after that. Maybe a rear end Lol. But I don't really feel like I have a torque problem just yet. I just wanted to reiterate to any passers by that I definitely lost some torque under 2600 switching to a single plane manifold with a carb pad height of 5.0" I appreciate your input and will check out these cams. But also want you to understand I'm not terribly concerned with any losses under 2500 rpm which I know and understand will effect my street driving experience. I probably could have picked a better intake to swap to. But I couldn't have picked a cheaper one. All together I have around 450 dollars in this swap all parts were used or fabricated by me or the previous owner of the Intake. Which I should thank again for selling me the Intake + rails and most accessories for the intake at such a reasonable price.

  13. #13
    Your a brave man to try that with a NV3500 and sticky tires. They dont like when you start slamming gears in them. Might want to invest in the short throw shifter.

    Ive been thinking about taking all the gears out of an S10 NV3500 and putting in my fullsize case. The S10 is suppose to have a closer gear spacing.
    2001 Jimmy ,L31 with marine intake,CPC conversion,Nv3500 5 speed,SAS,Dana 44's front and rear,4.30 gears..

  14. #14
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    I replaced the trans like 27,000 miles ago. shortly after I purchased the truck. I've been pounding on it for 26500 miles now lol. And i will add im not nice to it but i know hiw not to abuse it. Id'e be willing to bet my 100 dollar oreilly's clutch starts slipping before something in the trans breaks. I built a custom short throw shifter. A 3/4 steel plate between the shifter base and the shifter. Then I drilled a new hole 3/4 higher on the stick. Essentially creating the longer throw on the bottom point of the shifter on the end of the stick. It leaks but nothing to bad. If for some reason the nv3500 breaks. t56 swap finally!! the wife will understand after I take the ass chewing for tearing up a transmission with less than 100,000 miles on it lol

    Edit. There is two rpo codes the mg5 and the m50 I believe. My truck has the m50 code which is apparently the closer ratio trans. The truck has no options no power nothing. With the rpo codes for a l31 and m50 close ratio nv3500. Built in august 96
    Last edited by Oleblu; 01-17-2017 at 11:31 PM.

  15. #15
    I dont know what ratio my trans is. I traded a set of vortec heads for it and the transfer case. LOL
    2001 Jimmy ,L31 with marine intake,CPC conversion,Nv3500 5 speed,SAS,Dana 44's front and rear,4.30 gears..

  16. #16
    I think mine is an 92 down model. So according to this little piece of info I should be able to use the newer shifter base and just build a spacer.

    Damn we have derailed this thread. LOL
    Attached Images Attached Images
    2001 Jimmy ,L31 with marine intake,CPC conversion,Nv3500 5 speed,SAS,Dana 44's front and rear,4.30 gears..

  17. #17
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    Ain't nothing wrong with chasing the the squirrel up the tree sometimes. Occasionally distractions create innovations. Back on the off subject I have checked those short throw shifters from core shifters I believe. but shit man that's an expensive piece. Mine probably shortened throw by 25-28% it isn't anything special and like I said it leaks a little but i actually got paid to do it while on break at work haha. And back on subject Im going to start playin with my eoit tables I believe this will solve my issue thanks for the help man. I'll post some results later today hopefully.

  18. #18
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    well to no avail i adjusted my eiot tables up to 30% still had a lean tip in and rich off throttle condition. i then went to my fuel to wall impact factor table and stuck that one with 25% no change in the condition i got drastic and put 50% into the fuel to wall impact factor absolutely no change. im seeing as high as 18.5 afr during heavier throttle tip in. the recovery is relatively quick and fueling is staying stable overshooting and undershooting stoich by .5-.7 during closed loop operation . i have noticed the condition is worse when warming up. to the point of hesitation and backfire while driving during warm up. after coolant temps are over 130 the condition is just a tip in, off throttle issue. since im having so much trouble with the issue tomorrow ill post a log of the symptoms. along with the current tune im using.

  19. #19
    Advanced Tuner
    Join Date
    Feb 2016
    Location
    Texas
    Posts
    469
    Well finally I feel like I'm getting somewhere. after talking to a pro tuner buddy of mine we decided closed loop proportional fueling was where to start looking. I whacked 50% from my proportional o2 error gain and multiplier tables in the closed loop proportional and integrator section. The lean tip in has backed down into the mid 16's afr but the heavy throttle tip in is still going 17.5+ afr lean. still has a fairly quick recovery for the most part around a 1/4 of a second or so. i think im going to buy some new o2 sensors soon since the ones im running now only have around 165,000 miles on them. i wouldn't doubt they are getting lazy during switchover. they still match my wideband though the stoich of 14.68 in my tune is coming up just around 450mv so they cant be that bad off.

  20. #20
    Sounds like your getting it figured out.
    2001 Jimmy ,L31 with marine intake,CPC conversion,Nv3500 5 speed,SAS,Dana 44's front and rear,4.30 gears..