thehelix112

g260, Thanks mate. I'll give them a buzz and see if they have any in stock. Dave

Guys, I'm going to philip island next weekend and I don't have adjustable lower control arms, and unfortunately, no time to get some made. Does anyone have any laying about they'd be willing ot part with? Dave

Seems to me you can have both response and control depending on your definitions. Reponsiveness to me is a measure of the time between an input and a response from the engine/car, while control is a measure of how well/finitely you can adjust something. It would appear hard to have control without response however as good response means you are less likely to overshoot an input adjustment. But anyway John, WRT to your point, perhaps you are implying that at higher rpms the air is moving much faster and hence the response is that much faster simply because everything is happening faster? Better response leading to better control. I think control can be achieved at any RPM given adequate response and throttle travel. Given the choice between a slightly more difficult to control engine and one which requires rebuilding twice as often, I know which I'll be going with. Dave

Could I get some details on that too please jmark? I'm interested in seeing/ordering one. Dave

I have a solution. Power without revs and adjustable from daily drivable to track beast. Don't fight it, its natural. Dave

Gav, I don't really see the need for forged pistons in a N/A application, or a low-boost F/I application either. I assume that forged pistons weigh more than cast ones? Obviously they add strength and in a high-power F/I application this gives you more leeway with regards to detonation. Do you imagine detonation will be a problem on your engine? What CR will you be running? What fuel? Re dyno comparison, will be interesting indeed. Dave

gav, Kick toecutter into organising costa so we can have a turbo vs stroker dyno comparison and maybe some lunch/coffee afterwards. Dave

Phred, Awesome. I appreciate the posts/time. There is no way I would contemplate building my planned engine myself. I think I could rebuild an L (I never have), but I don't have the experience/tools to do it to this level. I have no questions (thank god I hear you say?) about your post, all makes perfect sense to me. Looking forward to more of your posts. Dave

Phred, I do understand that revs aren't the goal, horsepower is, not even that, torque is the goal. However in order to get the torque I want with a usable power-band I fear the engine will be required to spin to 9000. If i can get what I require from less than so be it. Good advice re valve spring pressure, all these little things that I haven't even considered yet. On a related note, how does one determine if they are getting valve float? Or is it extremely obvious once the engine is running? Light-weight valve-train sounds like a must. On Ti though, I have heard/read that Ti has limited life cycles unlike steel? Ie, it will fail after a given number of cycles? WRT displacement, I understand that the concept behind `there is no replacement for displacement' I believe, however, I have to weigh up the benefits of reducing cylinder wall thickness (reduced block rigidity and strength), increasing the likelihood of piston-jamming, and undoubtedly a host of other things I haven't considered when the HP increase could be made up with another few hundred RPM and/or few PSI of boost. That being said, interesting that you only mentioned 0.040 overbore? Taking bore to 87mm I believe. What are your views on the guys running 0.120 overbore on L31 engines etc? I'm not seriously considering it, more fishing for your comments on block strength? Also while I'm dreaming and picking your brains, on SCCA engines (which I'm assuming you have worked on judging by your comments) did you have any issues with blowing head gaskets between #5 and #6? If so, what was the solution? A fellow here in Melbourne (RPMZ) has had his head drilled and uses an external water manifold to ensure correct coolant supply (I think?). Also, what was the HP achieved from the SCCA turbo L28s? Around the 600hp mark as noted in various books? Kindest Regards, Dave

ATI make a twin-dampener for the L28 too: http://www.atiperformanceproducts.com/products/dampers/charts/damnissan.htm And Chris Wood (of Speed Technologies Melbourne) makes a very similar unit, also based on a BMW I6 dampener. Phred, nice post, people like you are the reason internet forums work as well as they go. Much obliged. I'm going to get laughed at, and I'm sorry for hi-jacking the thread, but while we're on the topic of high revs, say I was interested in getting my L28 to spin to 9000-9500 safely, you are saying this would obviously require titanium retainers, valve springs approximately how stiff? This magical (expensive) engine would be running custom forged billet crank, rods and pistons, dry-sumped obviously. What are the limits of standard nissan main-caps with ARP studs in terms of torque, assuming a precision balanced setup? Have you ever experimented with girdles? I fully expect to be laughed off as an internet-dreamer, so feel free to ignore that in its entireity. Dave

Jason, Can you tell us what you are basing that estimate on? Not trying to have a go, just want more information. I've heard stories of harmonics popping the ends of cranks (both ends) at 7500+ but thats not really pertinent to this conversation as I don't KNOW anything. Keen to learn. Dave

510 @ wheels? Thats a lot of power for that MPH. I ran 115 and I'd only guess mine was making maybe half that. Dave

Hey guys, The tard with the old-bodied 240Z and L28/GT35R would be me. Oh and the body isn't that old! My best time was a 12.83 @ 115 I believe. Was pretty happy with that, the MPH indicating its making some decent power (on a measely 11psi). I also think I saw sinisha (RB26 240Z) do an 11.9, but I don't remember the MPH. An NDSOC dyno day a while back it made 286rwkw, damn that thing moves! This was my first time out on the strip, and the 12.83 pass was my second pass ever, the first pass I had a passenger. Dave

Drew, Ratios are still up in the air, 4.4:1 will be crap for anything except very tight tracks, I've got a 3.36:1 and another LSD centre for it, would love to get my hands on a 3.7 LSD as well. Should keep all the based covered. In reality I think the 3.7 or a 3.9 would be much more useful than a 4.4. Cam profile in relation to boost, can't really answer this one, the cam is the most tame Crow cam you can get and I've never driven the engine without it. Feels just like a standard one except perhaps a little happier to rev. You can look and play with some different engine combinations' CRs and what not at: http://www.ozdat.com/ozdatonline/enginedesign/ 8.25:1 is the CR according to the info there. Dave

Just thought I'd update my ride, I went to the drags for the first time on the weekend, ran an 12.83 @ 115MPH with 11psi boost, single spinner diff, 195 pirellis. Couple of pics: http://www.burnoutsunlimited.net/events/nissdat2005/DSCF9073.JPG http://www.burnoutsunlimited.net/events/nissdat2005/DSCF8889.JPG

Did you consider the shockproof redline stuff? Thats whats in my box, apparently the bees knees - but how would you really know? Dave

Hmmmm.. can i say $5 and here you go *hands richard $5* Dave

Pro, The MAF measures the air before it is compressed as you say because it is calibrated to measure the temperature difference based on uncompressed air. MAF sensors have no issues at all coping with forced induction applications provided that all the air going past the sensor is then ingested by the engine - be it compressor and heated, or uncompressed and cooler. The only time you get issues is when the air goes elsewhere AFTER its gone past the MAF sensor (like a vent to atmo blow off valve). Oh and there is no way the pressure of an inlet charge is going to increase after an intercooler. In fact it is gaurunteed to decrease, the intercooler (and all piping/etc etc) is a restriction in the flow and will hence cause a pressure drop. Or are you saying that your intercooler is a compressor? I think you are possibly talking about charge density? Which is entire different and relates to the MASS of air flowing in.. and what does a MAF measure again? Dave

Pro, Thats basically an advertisement for a MAP sensors, from a company that sells kits for them: low-and-behold! And you still haven't addressed why a MAF unit is ``best'' for a N/A car? Dave

`Best'? Surely that depends on the design requirements does it not? I'd love to hear why you think a MAF is good for a NA car, and if it is, why its not good for a FI car. Dave

It is the job of the fluid to provide a barrier between the synchros and the gears they are accellerating. If the fluid is too cold (or too hot) and hence not operating at its correct weight this will cause the synchros to have trouble. (I think?) Thats why when the oil comes up to temp the problem goes away. Dave

I have heard tell of big hp engines ripping the LH engine rubber apart. Would make sense to me under the right circumstances. Dave

Zedrally, Yes indeed. Still gotta chain my block to the engine x-member. then I need the plates BONDGZ Dave

I've got a length of chain with a rubber hose over it in my car at the moment. Its perfect length so that it is taught when the bolts are done up. No issues as yet and about $5 bucks (and nothing to come loose too I suppose). Obviously has no adjustment and very little dampening effect but I didn't notice the difference. Dave

Oops.. hehe.. I'd best be shutting riiiight up then. If its hard to shift when its cold that would mean that the cold weight of the oil is too high perhaps? So maybe get some 70-90W? That might help. If I've remembered the correct way they label oils.. ? Dave