I've been having little issues here and there with my sequential twins since the time I bought my car. At first it was just a slightly rough boost transition, and then it started looking like my turbo control actuator was acting up (strange boost operation in 1st and 2nd gear, fine in others).

Then I started having strange bucking/hesitation issues like I've never heard of before (feels like fuel cut...we have been having some really cold weather and I got my tune when it was 80 degrees out...).

Now my car started falling on its face after 4500rpm, regardless of gear, and this is after replacing my TCA and my charge relief valve earlier. So now I guess that I'm having problems with my Charge Control Actuator. Oh joy.

Anyways, I'm now STRONGLY considering going single, but I'd also like to hear the opinions of people who still have sequential twins that are running well. I do have Knightsports twins, which have phenomenal spool (begin spooling ~1300rpm, at 12psi by 2000), and they do have very minimal lag at any point. However, I'm sick of constantly changing solenoids, and I'm also sick of having miles upon miles of vaccuum hoses to mess around with.

I currently have a PFS SMIC, and I also have an upgraded clutch, along with a Supra fuel pump and 1300cc secondaries. If I went single, I'd want about 330-375rwhp (being honest with myself here) on pump gas, with out glacial turbo lag.

However, are there a ton of hidden expenses I'm not considering here? I figure aside from buying a single kit, I would probably have to upgrade my IC (FMIC?), along with maybe some 850cc primaries. Is there anything else I'm forgetting?

I don't know, I feel like I'm just rambling here. I just want to DRIVE MY CAR, rather than FIX IT ALL THE TIME. And with a SMOG appointment coming soon, and a check coming from my university, I think it's high time to simplify things under my engine bay.


What do you guys think? Single or super-fast spooling sequential twins? Big thanks to anyone who actually reads this.

 

Why dont you go non sequential?

 

I feel like it defeats the purpose of having the sequential twins. I may consider it though, since it's a bit more simple and I could still do the rat's nest simplification.

 

Single turbo is $$$$$$$.. If you have the money go for it. If not I'd just go non sequential for the moment. My buddy has a gt35 with a streetported engine. The thing MOVES!

 

With those hp goals you should not need any primaries, stockers should work fine. really all I can think of that you would need is the turbo kit and a tune. That ic may work fine if you are only gong to be pushing 12psi or so. of coarse new ic tubing will be needed on the turbo side. If that is all the power you want with quick spool the GT35R kit is a great choice for you and is relatiely cheap. RX7store.net or A-spec can take care of you there. Hope this helps.... ( I am going single for pretty much the same reasons....)

 

There's a few good deals on lightly used single turbo kits out there...I could pick one up and it'd be practically free once I sell the Knightsports twins. Plus I have an M2 black powdercoated airbox that would have to go as well, along with the Efini Y-pipe. I'm seriously considering it now...

 

I just finished my single conversion, and there were a lot of incremental hidden costs that added up......intercooler piping, silicone couplers, t-bolt clamps, thermo-sleeving of varying sizes, assorted hardware, heater hose and fittings, stainless steel wastegate lines, manifold gaskets, silicone hose and vacuum fittings, barbed fittings for omp, etc etc. I'm not saying 'don't go single turbo,' just saying that if you want to do it right with quality components the little costs add up. Check this link out, lots of good info and page 4 demonstrates what I'm talking about:

http://www.negative-camber.org/crispyrx7/gt35rpage1.htm

 

Thanks Rich, for reminding me that this is not an FC. You can't just rip everything off and slap on a turbo, hahahaha. I think I need to be realistic here, and considering my budget I don't think I would want to attempt the conversion, because the last thing I want to do is half-*** something on this car.

I do have an HKS stainless manifold and an HKS 40mm wastegate laying around, though...so I'm still tempted somewhat. I think I may just go non-sequential, simplify the mess under the UIM, and take out my cat to see how much power I can make with these Knightsports twins instead, though.

 

I have been in your exact position before. I tried for 8 months straight to get my sequentials to work with no luck. I honestly put over a grand in actuactors and solenoids. Made me want a single real bad. But the car that was fitted with stock twins got totaled and I purchased an FD with a single turbo. My new fd has the Rx-6 single which is one of the smallest turbos on the market. Its a true bb turbo so it spools up real fast. I see 16psi around 3000 rpms. I just run an asp large smic so intercooler piping is simple and cheap. I just dynoed my car a few weeks ago with this setup. Running 10 psi and H20 injection I put down 300whp even. Then at 16 it did 362 with h20spraying pretty good.

My advice would be to keep your eye out in the forsale section for a single kit somebody is parting with. There are many people who get rid of great setups that really perform well for cheap. I would look for an RX-6, Gt35r, turbonetics 62-1, or any of the smaller singles.