JP got in excess of 407rwkw on the dyno. My engine has been built to "stay together" not to fly apart. You have to do the ground work, if you don't want to be crying later.:zlove:
CHILLI does having forged pistons means you can boost heaps more? and what do you have to do to make the vg30 a low compression engine? iv heard the term low compression and that you would need it to boost over 20psi.. Also are the rods in the vg30 engine forged as stock? cheerz
All TT's have lower compression than NA's (8.5 to 1) Forged pistons allow you to run higher boost with less risk, but there are limits to everything. The forged pistons in my engine are "9 to 1" C/R, this is simply because that was all that was available(and was not considered to be problematic). We could have lowered the C/R by using thicker H/gaskets, but that was thought to be be un-necessary. Forgies are generally lighter and stronger than OEM pistons, so there is less moving weight in the reciprocating parts of the engine(a GOOD thing:LOL. VG Rods are forged, but can be improved by shot-peening and linishing (as used in my engine). Stronger bolts(ARP) are also extra insurance.
Roughly how much is the 8.5:1 pistons? So to rebuild the engine for power and reliability i would need: forged pistons shot peened and linished rods Thicker head gasket Stronger bolts Sweet thanks im just trying to make a list of everything need to be done..so when i give it to the mechanics i know what they are talking about and i dont get ripped off cheerz
more info >> The STILLEN set is $ 2,530.00 (PN# 4093851) and the requires the JE Ring set at a cost of $ 295.00 The off-the-shelf ones with a Compression Ratio of 9.0:1 is $1,710.00 and to lower the compression ratio you would need a metal head gasket like the HKS or Tomei ones which are around $750 a set. I got the 9.0:1 pistons with a 2.0mm Tomei metal head gasket because my heads were shaved 15 thou and there's another thou in HPC coatings inside the combustion chamber plus I wanted a CR of around 8.0:1 so I could run potentially up to 30psi boost. Almost everyone runs 1.5mm metal head gaskets which lowers your CR down to 8.25:1. Billet Crower 4340 conrods are around $2800 which is what I used. These come with 220,000psi strength conrod bolts and for another $450 you can get 290,000psi ones called H-11 bolts. Titanium valve retainers are also good to lighten the valve train for more HP and they are about $600 a set I think Depending on what turbos you get but if you are getting something like the GT2530 or GT28R then I'd suggest getting JWT heavy duty valve springs and their R4 cams with adjustable exhaust cam sprockets. Also a kevlar timing belt is handy to keep it together.
You really don't need the thicker Head Gasket.:thumbsdown: If you get 8.5:1 pistons, there will be no difference from stock. If you use 9:1 pistons you can please yourself about the thicker gasket. I didn't worry about it, but I did use a gasket from UAS, that has seperate sealing rings (for a better seal at higher boost levels). You would get better value by using the new composite Plenumn Gaskets from UAS, as they insulate the plenumn from "heat soak", which helps to lower inlet temps (a much more critical factor than the slightly increased compression ratio).
All good advice, Shane, but I think ak's budget has just evaporated.:LOL: Tell me again, about how easy(and cheap) it is to get 300rwkw.:LOL::LOL: You need to think in terms of rear wheel kilowatts, as most people are quoting figures from dyno runs. The figures ZDUCTIV gave you, were flywheel output, NOT rwkw, there's a BIG difference. As an example, my car is producing 271.9rwkw (which you think is not enough), but it is producing 365kW @ the flywheel.
flywheel horsepower means zero >> unless you put the engine on an engine dyno and I don't know of many places that would do an engine dyno run on a VG30DETT. Even rear wheel dyno figures are pretty bogus when you can tweak the output readings to make the customer happy. I'm always suss of dynos when sitting there with no car on the rollers and reading 4HP. In the end it's the combination of machine and driver that makes a fast reliable car so 1/4 mile times and track times are the only indicators of how well a car performs in my books. Not much fun driving on a dyno 2.8k conrods 1.7k forged pistons and rings 1.0k injectors 5K-7K simple rebuild with just a tidy up of ports 0.6K bronze valve guides 0.7K clutch 0.5K gaskets and seals and that's 14.3K with more to add and no labour to remove or install the engine if you can't do it yourself. People will believe what suites them best.
Dead right Shane. Those figures you quote don't include turbo's or any other item either. BTW my previous post was mostly aimed at ak, not you.:LOL::thumbsup:
Lloyd, Shane This is great info !! This is turning into a really useful thread. IS there any more stuff about your engine rebuilds you guys have learned that you can pass on to us beginners ?? Having a shopping list of things that really have to be done is half the battle. Learning from your experiences is worth its weight in gold. Any more about parts that would normally be bought for a rebuild that wont hack it? Any bits we should watch out for cause they are not good enough?
I could fill a book on the stuff I've learnt >> on the zed engine and suspension. I'm concentrating on suspension at the moment by converting all rubber/silcone/urethane bushings with spherical or roller bearings and solid alloy bushings. Might be a pipe dream but I hope to one day make modifying/rebuilding cars as my full time job. Being a qualified electric/mechanical engineer but working as a software architect suxs arse.
I love it when the zexperts get technical and informative.. thanks chilli and chewy I went to a place in Yenorra Sydney that specialise in rebuilding engines. The guy quoted me $1500 to take the engine out and back in .. and $4500 for a rebuild... 1: Now a rebuild just cleans inside the engine or do they shave and bore? i dont really know what these terms mean but what is the process of rebuilding a vg30dett stock without adding extra bits..?? 2: I purchase 8.5:1 pistons (wats the ratio on the stock pistons?) (also if i get these no need for thckr gasket?) Thicker Head Gasket Keep the stock rods (shot peened+linished) How much would this cost $? stronger bolts Bronze valve guides ( whats is these for?) Thanks buddeis :thumbsup::zlove:
geeze thats only just getting warmed up. $1500 is a good price for removing and reinstalling the engine. Make sure you get these in written quotes!!! Cant remember how many times people complain on here (including me) about verbal quotes you get screwed on. Make sure they are detailed. For instance you can bet that the R+R of the engine wont include regassing your a/c. Not to mention it cant just be regassed it needs conversion. In my case the seals on the compressor cracked as it was out for 24 weeks. $800 later my a/c worked. Things that MUST be replaced IMO: wiring harness $850. You cant expect to get high HP reliably while having dodgy connections. no way around it. Engine studs and pulley studs approx $300. Full 100k kit $800, kevlar timing belt $300. Replace all sensors. You dont want to start with a fresh block for it to be limited by dodgy, corroded extras. Unless they were EXTREMELY confident I wouldnt get them to use ringed gaskets. Ive seen/heard of more fail than succeed this way. Composite is better IMO. $4500 for the rebuild, clarify exactly what that includes. It may not included any head work at all! Some engines had harder intake valves and these need to be replaced. Look at porting and polishing and other head work and the $$ mount fast. Ive been quoted nearly 4k just to port my heads only. If you want high HP, you want to think about getting better cams. These really improve your power curve. However 1-2k for these, plus all new lifters at about $400 i think. You need new injectors, 555s at least. Probably 1k give or take. Id also recommend a new fuel pump for safety although optional. Their quote may not of included balancing, best to check. You will need something to retune this. Either stock ECU rechip or a new computer. Starts from 1k, goes to 8k. Need intercoolers, $1500, high flow exhaust with 2.5" piping, $$$$, can probably get by with single intake but may need dual, so look at another $700 for a dual maf system unless you went with a new ECU. Heaps more to be said but that the basics to consider IMO.
