thehelix112

I would be guessing Aluminium Berrylium Metal? Dave

The rough figure I've read is around 85% for a 2vpc engine like the L. Though based on some dyno information from a comparable engine, I think closer to 90% (at max torque) with a cam and some minor porting. Dave

Right. Believe it when I see it. (Honda guys that aren't bullshitters AND 1000rpm lower boost threshold). Dave

You are around 2 years, 5 months and 13 days too late. Check the date on the post you replied to. Dave

1000rpm? Got any evidence of that? Sounds like far too much to me. Depends far too much on the size of the turbo, the size of the turbine, etc etc. Dave

To properly bore any engine you have to have the main caps installed, a torque plate installed, and water temperature up to operating running through it. Keep hunting. There is a thread floating around, I think by johnc, or braap, or someone with a lot of knowledge about the pistons they used in their race engine. These pistons had a dish the shape of the N42 chamber to achieve nicer squish. Hopefully they'll chime in here and correct all the mistakes I probably just made. Dave

That'd do it. I wonder what that would do to the spool characteristics as it is likely the GT32 turbine housing is physically bigger than the GT30 one. Dave

I don't really see how that can be the case. The GT30 wheel is 60mm with a trim of 84 (making the exducer around 65mm), while the GT32 wheel is 64mm with a trim of 73 (making the exducer around 75mm). How can a bigger housing be used on a smaller wheel? Or maybe I've got the trim calculations mucked up. Dave

I am slowly working my way through Milliken & Milliken. Slow going (I did Computer Science at Uni), but lots of information to learn. Dave

One of the biggest advantages from a track car's perspective in the GT range is the high-nickel context exhaust housing. This stops the housing warping/expanding/going off. A mate needed a fresh housing every 2 meets on his old T4 but has run his GT35R for 3 seasons with no changes. I would be careful about changing the housing to one made by someone else. I suppose you would need to justify the gains from having a split pulse housing (and manifold) against the potential for turbine housing problems (if its going to be raced). Dave Dave

This is why my gf doesn't want me to road rage in the states. Dave

I can only imagine. I know I really should ask them this, but would you recommend taking the TIG/MIG courses as a pre-requisite for the motorsports classes? This is sounding like a worthwhile investment. Dave

Yikes. Those anocedotes make me scared. Lincoln motorsports welding school sounds like it might be a good investment for anyone interested in welding cages. Here is the link I believe: http://www.lincolnelectric.com/focus/motorsports/school/school.asp Worth the money do you think? Did you do the beginner or advanced course john? Dave

Woh, you can buy fibreglass dashes for S30s?! When did this happen? Oh hang on, they're going to be LHD aren't they.. dammit! Dave

What compressor are you using? One option is to use elec boost control to gradually increase the boost limit with rpm so you never get into surge. Thats what I plan on doing. You also get the added benefit (well a benefit with a new garrett BB turbocharger) that boost doesn't hit quite as hard. Makes it a lot more controllable. Dave

I thought thats the point of yield and ultimate strength metrics? And who says chromo is brittle? If you are talking about the joins after welding, maybe you should re-read some of the links a few of us posted earlier. Aside from thats, I interpretted your original post as johnc did. Dave

What Jeff said makes a lot of sense to me. Dave

John, I posted the quote and link because I learned a lot from the article. Sorry if you didn't do the same, didn't mean to waste anyone's time. So the conclusion is that we can weld 4130 with 80S-D2 filler using as small as possible convex welds in a still warm room and everything will be fine? Dave

We need a metallurgist. From what I can find, ``with more modern welding process like TIG and MIG, the cooling rates can be much faster and care must be taken to avoid forming high hardness and brittle Martensite on cooling transformation. On heavier sections preheat and post weld heat treatment should be used.'' (http://www.netwelding.com/Welding%204130.htm) The key point here is heavier sections. The lincoln electric link you posted does mention the lack of heat treating and post heat treatment is only suitable for <3mm wall thicknesses. As a side note, as that netwelding.com article says you should have convex welds to keep the weld area not in tension. Dave

Nice link, but not particularly applicable. You're not going to be quenching or tempering anything other than air cooling, and according to the interweb (large grain of salt applies), such heat treating is not required for the wall thicknesses you are likely to be using (<3mm) (pun). I am in the process of designing my rollcage, will have to make some sketches and post pics shortly. Best of luck, Dave

Nice work. Dave

Sounds like a handful. Interesting that the insulation lowered intake temps so much. Is that at speed or stationary? Dave

I guess you find that your car feels like a weapon on the street, and a boat at the track. I hate that. Dr_Hunt, I can make just over 5psi in neutral with 3 consequtive WOT jabs on the throttle and thats with a GT35R. Dave

ZFury, I agree. That is my favourite Z car pic bar none. Dave

Friend runs a RB30ET/GT35R race car in NZ and has the same experiences as what Careless mentions. With an auto (yes auto track car) and 0.82 housing it was undrivable. 1.06 and a proper boost vs throttle position map and all is well. Dave