Z_WAAAAAZ

Hey all! I'm getting ready to start sourcing parts for the VVT motor that'll be going into my '95 dual duty car. I already have a good idea of what I'm going to do for the "meat and potatoes" part of the build, but would like some input on where to spend any extra dollars if I increase the budget a bit. Obviously, I don't want to break the bank any more than necessary but I'd rather spend the money now and do this whole sucker right the first time.

The motor's going on a car that's used for track duty and canyon runs. My current motor is running strong but has over 200k miles with around 30 hours of track time on it, 5 or 6 of those hours with a turbo. I want to build a sturdy motor that can handle more power to swap in before I run into any problems with this one. Current turbo setup is a Kraken top mount/GT2560r/full 3" exhaust. MS3X for engine management and a DW200 fuel pump with FF640 injectors for fuel supply. I'm currently running pump gas but have plans to add a flexfuel sensor and E85 tune before the new engine goes in. I want to run somewhere in the mid-high 200whp neighborhood once the new motor is done, with headroom for up to 350whp if decide to upgrade the turbo, transmission, and injectors down the road.

Current wish list:
Rods: Manley H Beam
Pistons: Supertech 4032 84mm 9.0:1 w/ Wiseco XX rings
Bearings: ACL Race
Oil Pump: Billet Engineering Stage 2 w/ 2 shims
Crank Damper: ATI Superdamper
Hardware: ARP Main Studs
Valve Springs: Supertech Doubles (Still need to decide on light vs heavy)
Skunk2 or Squaretop intake manifold (Have a VTCS currently)
Get some mild headwork done at the discretion of the machine shop
All OEM gaskets of course

My current question is this: If you guys were to spend an extra $1000 on this build, where would you spend it? Oversized valves? Cams? Enlighten me. Tear me apart. I just want another set of eyes on this project haha.

psyber_0ptix

iTrader: (4)

I'd recommend heavy valve springs. Imagine whatever amount of boost you want to run is pushing on the back surface of the valve. 20psi is 20 pounds on the back of a std 33mm valve (~1.32 in^2 area), your springs are fighting an additional 26.4 lbsf. If you want to build for headroom, just go for heavy. What transmission are you using? FM2 is a great clutch for the 350whp range, but it absolutely failed to hold 400whp. Analysis by Competition Clutch (who manufactures the FM2) said it was simply overpowered I wish I had just gone for the 949 twin disk from the start, but i was chasing the 1% of power which I do not recommend.

If I could do anything, I'd have left my car at 350whp as that was peak fun. You can achieve 350whp without e85, and adding e85 you're looking at ~30% overhead on injectors. Just keep that in mind for long term planning/purchases.

I'd recommend:
- Dont worry about cams, your target power is achievable with stock
- +1mm O/S valves can fit in existing valve pockets on the Supertech's, any larger you need to clay.
- Don't do e85 unless you just want the experience and smell. You burn through it faster, you need more injector, and balancing the tunes....you can easily achieve your goals on pump.
- Invest in your driveline so you don't have to revisit. Good clutch, and 6speed if you don't already have. If you feel like spending, then the Getrag is king.

Higher than the amount of your slush fund. The biggest thing that enhanced the performance of my old car was an OS Giken diff. It felt like a completely different vehicle and inspired way more confidence on track/corners.

Z_WAAAAAZ

Hey, thanks for the response! And for the input on power. I think 350whp will be the absolute ceiling of what the car will ever see. For the foreseeable future, I'd like to get the car into the mid-high 200s for track and maybe low 300s for street use. The car still has 210whp currently and I'm having a bunch of fun with it. Maybe a handful of years down the road I'll get a wild hair up my *** and go for broke with a Getrag and beefier rear end. One project at a time though.

Alright, good point on the valve springs. I'm gonna go heavy for the reasons you listed. I had a hunch that was the way to go.

I'm on a 5 speed right now but am going to get a 6 speed for the car before going over 250whp. Currently running a Supermiata sport 4-puck clutch rated for 340lb/ft at the crank. I'll have to look at some other guys' dyno sheets again to see what 350whp generally nets for wheel torque. My impression is that the clutch should max at around 280-290 wheel torque.

Again, I appreciate the input on the rest of the build. I was thinking doing cams or a crank would be a cool addition but I kinda knew that'd just be for show at the power level I'm going for. I'm gonna add some +1 valves to the build and go inconel on the exhaust side for added safety. Mind if I ask what you're running?

sixshooter

iTrader: (12)

Titanium retainers for reduced mass to aid in opening and closing the valves.

I don't see the need for oil pump shims.

You don't need cams for any of your goals.

Z_WAAAAAZ

Titanium retainers added to the list. Thanks for the input. Hadn't heard much regarding these while looking through other peoples' builds.

What're the drawbacks of running the oil pump shimmed? Most of the similar builds I've seen on here with BE oil pumps seem to be running with two shims.

Time to make some more internet searches.

sixshooter

iTrader: (12)

Shims effect the maximum oil pressure allowed by the pump, which is usually seen when cold. At operating temperature most engines don't hold maximum oil pressure unless there's a problem. Oil volume being delivered is more important than maximum pressure. That's why Boundary uses VVT (high volume) pumps exclusively now.

High maximum pressure subjects the oil pump to additional forces and the creation of excess heat and wear that simply aren't necessary in most cases.

Z_WAAAAAZ

Killer. Thanks for the explanation. First time I've heard a case for not running the pump shimmed.