skirkland1980 Posted July 18, 2013 Author Share Posted July 18, 2013 Thanks for the info on the lash pads. The turbo is a Garrett TC4305 58mm compressor with .82 ar turbine. Quote Link to comment Share on other sites More sharing options...
Pyro Posted July 19, 2013 Share Posted July 19, 2013 If your turbo doesn't make full boost until 3500 rpm+ then that is a sign of a free flowing turbine. Which means that turbo can handle some valve overlap and would work well with a cam with around 270 degrees of duration on both the intake and exhaust. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted July 20, 2013 Author Share Posted July 20, 2013 If your turbo doesn't make full boost until 3500 rpm+ then that is a sign of a free flowing turbine. Which means that turbo can handle some valve overlap and would work well with a cam with around 270 degrees of duration on both the intake and exhaust. Great! That's exactly what I have ordered. Quote Link to comment Share on other sites More sharing options...
ram75280z Posted July 27, 2013 Share Posted July 27, 2013 What you really need is a new intake manifold with runners that have a diameter of at least 36mm. You can change the cam & turbo, that will give you more power, but it won't extend your powerband at the top end unless you have an intake manifold with adaquate runners. A 270 cam with 36mm runners should peak right around 6500rpm on an l28. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted July 27, 2013 Author Share Posted July 27, 2013 I know what you mean. I cut my N42 intake open to port both ends of the runners. I can only get about 1 3/8". I can't remember what that is in mm. Quote Link to comment Share on other sites More sharing options...
ram75280z Posted July 27, 2013 Share Posted July 27, 2013 The stock n42 intake manifold has runners of about 31.75-32mm(you can't really even say they're that size unless the casting from the injector screws is taken out), equal to 1 1/4in, so either your manifold has been ported or your measuring is a little rough. The late model, 82-83 turbo, intakes are 32.75-33mm. There's a lot of information about the intakes on this site. The simplest route to resolve this issue, if you have the money, is to purchase one from Lonewolf perfomance. I think their basic model starts at 35mm, but they will make them how you want. Or they will port the stock intake, the full length of the runner, but I don't think they have enough material in them to make the runners any bigger than 34mm. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted July 28, 2013 Author Share Posted July 28, 2013 What I meant was I've ported it to 1 3/8". I wouldn't feel comfortable going any bigger. The o.d is only around 1.60". The biggest problem I see with the N42 intake is the egr port bosses for the lack of egr ports. They take up a good bit of the runner entry. Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 28, 2013 Share Posted July 28, 2013 (edited) JeffP's runners are the FIA homogolated size, -1mm (34mm) His head has 35mm ports that flow 218cfm, the 34mm extrude-ported runners lose 30cfm over a match-ported Cannon Manifold. But it does have apt hat anti-reversionary step at the head to help with overlap reversion. 700HP+ on C16. More possible so he's looking at the Group Buy Manifold being done now as he wants to retain the stock runners (shortened) for now... Edited July 28, 2013 by Tony D Quote Link to comment Share on other sites More sharing options...
ram75280z Posted July 29, 2013 Share Posted July 29, 2013 JeffP's runners are the FIA homogolated size, -1mm (34mm) His head has 35mm ports that flow 218cfm, the 34mm extrude-ported runners lose 30cfm over a match-ported Cannon Manifold. But it does have apt hat anti-reversionary step at the head to help with overlap reversion. 700HP+ on C16. More possible so he's looking at the Group Buy Manifold being done now as he wants to retain the stock runners (shortened) for now... Hi Tony, Do you know where I could find a dyno plot of Jeffp's engine? I searched around a bit, but the posts were circa 2007ish & the photos were gone... Quote Link to comment Share on other sites More sharing options...
Tony D Posted July 30, 2013 Share Posted July 30, 2013 Yeah, those were before I had my "Every Time You Talk To Me, It Costs Me $2,000!" talk with Jeff and he started making real power. Actually right now, running on a STOCK L28ET BOTTOM END he's exceeded those numbers from the Rebello 3.0 Stroker that are posted on his website. The Rebello sits pickled in the corner of the garage until he hammers out his EFI Issues. He stopped posting a lot of that stuff, just too much B.S. Benchracer wanker background noise to deal with... We continued testing like before the internet existed. What do you plan to gain from viewing the dyno plot? "Is it a peaky engine?" No, the car makes 2-3 PSI at any point in the RPM range when going WOT, and Full Boost occurs like clockwork at 3200, the came comes on around 4,000 and pulls to over 7500... It accelerates with me in it as ballast (tire slippage) from 70-120 in around 4.5 seconds...then you shift to 4th. Extrude-Honed Stock L28ET Manifold, on Gerolamy Worked Head (head match ported to dowelled Cannon 45mm Triple Manifold), and Isky Cam. He GREATLY laments not listening to me and making a full-rpm 8psi of boost run to redline to see where the power peak of the engine really happened. The GT35R is OUT of air at this point, and unless he upgrades, or puts a forged bottom end back into it to make a full RPM run we can't extrapolate the actual potential of the setup. The one pull I did note at 8.39psi he was making 380 ft-lbs of torque at 4500 rpms. I got videos of these pulls someplace. And of the later pulls in the engine dyno test cell when we were doing oil temperature stability testing. But no time to post, nor any real inclination to do so... Just my memories of what we did while in active development. Life has intervened for both of us, and we are both on hiatus right now from developing it fully. Quote Link to comment Share on other sites More sharing options...
ram75280z Posted July 30, 2013 Share Posted July 30, 2013 Yea I remember the earlier days of the build(almost 15yrs ago if i remember correctly), posted on the internet (zcar.com). I had forgotten about his web site over the years though, which I found today. In reading it again I remember reading it before. It was the first well known, privately built, high hp l28et that I remember. It is kind of disappointing that there's not a full plot of the engine. Especially since it is so well documented & well done. Mostly I was curious about the affect of the intake on the powerband, as I'm currently working on a 34mm turbo intake for my NA l28. Honestly, I'm not extensively versed in turbo tech, but the amount of power being made with 8psi sounds like the turbo is pretty well suited. But, I do know that it's probably more suited to a 2 liter engine for high hp levels. I bet you two have had a lot of fun over the years working on it & talking about it. Hopefully you will both be able to return to all of that soon, & get to record the true capabilities of it. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted August 7, 2013 Author Share Posted August 7, 2013 Well haha! I've come to a conclusion about the N42 intake manifold. It's junk! I made a big hole just trying to reach 1 5/16 on the plenum end. Such crap! It's back to my steel intake. I started another thread about Delta cams. This is my first time using them and I'm not impressed at all. They sent me a stock regrind whereas I should have had .450" 272 duration. Quote Link to comment Share on other sites More sharing options...
Tony D Posted August 7, 2013 Share Posted August 7, 2013 1 5/16"? What that in real measurements, and not graduations of The King's anatomy? 33.3?mm? Quote Link to comment Share on other sites More sharing options...
BLOZ UP Posted August 7, 2013 Share Posted August 7, 2013 (edited) If your turbo doesn't make full boost until 3500 rpm+ then that is a sign of a free flowing turbine. Which means that turbo can handle some valve overlap and would work well with a cam with around 270 degrees of duration on both the intake and exhaust. You could also measure the intake and exhaust manifolds pressures during a pull and see how likely reversion is. Edited August 7, 2013 by BLOZ UP Quote Link to comment Share on other sites More sharing options...
Tony D Posted August 9, 2013 Share Posted August 9, 2013 JeffP did that and was shocked to see he same pressures under load at full boost and 7,000 rpms. His GT35R comes on at 3,200 like clockwork. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted August 9, 2013 Author Share Posted August 9, 2013 I drilled and tapped a hole in the exhaust manifold but never measured exhaust pressure. That is some good info about that. In that case a special turbo grind would be unnecessary. Any na grind would work just fine. Quote Link to comment Share on other sites More sharing options...
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