Hey guys, I know of a few threads on this but just chasing some more advice. I plan on building a new motor regardless. I'm currently running a RB30et, with hypatech pistons, stock rods, rebuilt not that long ago really. 818b cam, springs, head studs, 6 boost manifold, gt35 and cpc plenum. Car made 389hp on about 21psi and ran 119mph 98ron. I want to dip well into the 10's and maybe even 9's most likely on 98ron, and keep it as street-able as possible (With in reason) I've been highly considering going down the rb30/25 route. Probably stock head to start ( forged bottom end) And getting new manifolds etc to suite. Or do I build for a SOHC. Change cam, maybe port the head and bigger valves? Am I going to get much gain from what i have now And is this going to be anywhere near the same level as a 25/30 setup on similar boost levels etc and drivable. I'm well aware of what GH etc have achieved with sohc but these cars are far from street cars.. Any advice would be great from people in the know. Cheers Ian

Try pump e85 in your current setup and put some boost and timing in it should do low 10s no worrys

Quote: Originally Posted by madrex [View Post] Try pump e85 in your current setup and put some boost and timing in it should do low 10s no worrys I'd love to try pump e85 but we don't have any access to it up here. The only way of getting e85 is shipping it up in drums.. Which is the reason for wanting to run unleaded 98.

Aiming to do high 9s, sohc is the clear choice. Obviously need the supporting driveline but other than that its so easily achievable even with your current engine setup. Just ship a 200L drum of e85 up to you, will cost 1/10th the price of going twin cam etc.

SOHC sounds better and is how holden intended the VLT, probably easier to maintain as well, DOHC sounds like cheating on a VL.

If you want to run 9's on pump...you'll probally blow it sky high..and you have to run really low comp to do it, and that will make it doggier... spike the fuel, just buy methanol and do a mix if you can't buy E85, or wmi.. if you already own all that crap..youd be a moron to sell it for $2 and start a fresh if you liked getting ****ed in the ass...twin cam may be a good choice. then again if thats your thing, it will be cheaper to book a flight to sydney for the mardi gras..lol theres plenty of upgrade turbo in a T3 frame that will bolt on, and run 9's its a no brainer...change cam/change turbo cheers darren

Yeah thanks guys, I'm starting to think the single cam is going to be the best/cheapest way to go... I've found a engine that's just been built just needs some good rods with a maatouks head package on it (Apparently port job, springs, collets,retainers and 'Maatouks spec cam'. Might be the way to go...? Cheers Ian

spike fuel or change it.. smash boost, run it till it blows... your current bottom ends only worth $1500, who cares if it takes a crap? or spend ****loads straight up....lol.. cheers darren

Well our strip won't be open for another 9-12 months so was just going to start getting a nice combo together.. Hence trying to work out which way to go with it.. And I can start building up something decent

i have had all the head combos (single, 20/30, 25/30, 26/30) so far and currently have the 26/30 in the car. Darren is right don't waste your money on changing to twin cam as your current setup should do what your wanting easy. Also don't waste your time with the 98 fuel just do a mix for racing and then keep the 98 for street purposes cause you will always be limited to around the 21-24psi mark depending on comp and your setup can push passed that with better fuel. With the bottom end don't change it until it fails as your just wasting your money but put money aside for when it does so you can put it all together when the time comes.

Quote: Originally Posted by Boyracer [View Post] SOHC sounds better and is how holden intended the VLT, probably easier to maintain as well, DOHC sounds like cheating on a VL. exactly my thoughts Some original photos have not been recovered yet.

You could also try to make the car liter within reason, For example any thing that you can unplug, cut, unbolt or do without will help you cut time and it can be done for nothing!

Thanks guys, Probably will stay with the single cam setup I have now. What's peoples thoughts on an e-flex setup ( E-flex sensor etc so I can run e85 but also run 98, and the ecu will compensate with the tune)? Or just run a fuel cell with a drain... Running a Vi-pec V88 which from what I can see will do it.. Also can you guys recommend a cam to suit, and perhaps just out of curiosity what the best way to go with a turbo down the track? Cheers Ian

I have a well proven head for sale with cam Flex sensors are great, im sure the vipec can run one, will be the best way to go! Depends how fast you want to go, I love my gtx42, its been amazing. I have a bl375r also, its was awesome too, ran out of puff at 153mph but was a great/responsive turbo! Its also for sale, I will do top deal for the head and turbo, together they have gone 153mph @ 35psi on eflex. Some original photos have not been recovered yet.

go twincam

Hey Ian, I'm pretty sure Leigh at svs sells e85. I'll have a talk to him next time I'm in there. He's building me a tuff rb30 ATM for my vl.