I've been planning to do an E85 conversion on my stock block setup for a while now, but I'm having second thoughts. My setup is in my sig, but basically BBK-Full, Kelford 272s, ACT HDSS, and stock block. Currently on 93 octane for street driving and 100 octane for road racing, the car sees regular track days and autocross but no drag racing.

I have a 2.5'' HKS downpipe, and stock o2 housing, so I've been planning to get a MAP o2 dump and 3'' downpipe to free up some restrictions, but figured I would drop in a Buschur double pumper, some FIC BlueMax 1450cc injectors and swap to corn when I retune. I have an E85 station <4 miles from my house, so its easily available and I have other cars for long trips.

My main concern is that its a lot easier to build a motor without rods sticking through the block, and I'm worried the torque hit from the BBK-Full on E85 will put me outside the safety margin on the stock rods. I've been considering building a 2.3L motor, but I'm concerned my OEM transfer case or ACT clutch won't hold the power of a 2.3L on E85. I'm also not sure if the BBK-Full is just too small for a stroker on corn. I do not care about street manners as the car is gutted and fully caged, but I don't have the scratch to do a new motor, new clutch, new transfer case, new turbo, and E85 conversion all at once. The car will be trailered next season so I will not have to worry about driving to track days.

Should I:

A) Leave the car alone and keep driving my current setup with no changes.

B) Leave the car on 93/100 octane and do the o2 dump/downpipe for a few extra horses.

C) Do the o2 dump/downpipe and E85 conversion on the stock block and run my stock block for another season hopefully without the motor eating itself.

D) Build the 2.3L stroker with the current turbo/cams/head/clutch setup I have now with E85 conversion.

 

Ok, almost 60 views and no responses...

Does anybody at least know if the BBK-Full is too small for E85 on a 2.3L? I know its intended range was only up to ~29 psi. Anybody have posted results of E85/2.3L/BBK Full?

I'm leaning towards just doing the dump/E85 tune now, and holding off on the motor build.

 

If i was you I would just throw some e85 in there do the dump/DP combo and Have a good tuner work on keeping the Torque on the low side for Extra safety margin. BBk with stock motor and e85 WILL keep you happy for a while.. 400wtq is awesome to have and you should be able to hit that.. Stock block/clutch/TC will last aslong as the power doesnt come on too strong at once.

 

AWD Bastard Evo ran the BBK on their 4g64 with MIVEC head and made, dont quote me, 552whp and trapped 136mph.

Even if you don't build the motor the BBK will be fine on the stock block. I made 450whp @ 29psi on 94 octane and 500whp/427ftlbs @ 33psi on E - search for some of my threads if you like, I list the mods. These weren't "road race" tunes either hehe so your results may vary. Definately get that 2.5" downpipe out of there and get a bigger fuel sys like your planning on doing. You should be a happy camper!

 

I would just do A, but Im a minimalist. I like doing the most with the least. Nothing like having people come up to you after a session scratching their heads wondering how a stock car on street tires got around their trailered race car on R-comps.

IMO; drive the car till you're able to keep it at 9.5/10ths for a whole session. when your lap times are all very close for the whole day then you know its time to upgrade/change something. It doesn't have to be a part on your car that gets changed. sometimes it can be the line you take or the technique you're using or even the gear your in.

The setup you have in your sig should be VERY fast and more than enough power for lapping days/HPDE. I've driven an IX with a BBK full and it was an awesome setup. So responsive it almost felt like an all-motor car. if I was building an HPDE car to play with THAT would be my turbo of choice.

 

The BBK will serve you well on a 2.3L and E85. I feel tthat is a perfect street and road racing setup to start off with.

For refference Im on the stock block maxing 460/410 with a 6 speed and a BBK-B, my car is holding up but I dont expect it to last for long, I will be going with the 2.3L for sure in the near future.

 

It is VERY fast on track... there is no question that I don't -need- a single drop more power than I have. Honestly with my current levels of downforce much more power could be a "very bad thing" (tm). I just hate having to run 100 octane at the track though, and with E85 just sitting next to my house I've really wanted to upgrade for a long time. However, I don't want to swap to E85 and send a rod zipping through my block.

I'll be honest, I love the BBK Full. Even on the stock block it is super responsive, and the powerband is perfect for track days. I don't think I ever want more than ~550 whp on a road racing car, its a monster at 400+ already. I am still leaving huge chunks of time on the table even at my home course, so I know a lot of improvement can be made from further practice. I've started doing autocross now as a learning tool and I'm really enjoying it, although my car is certainly not set up to be competitive at autox. I'll be running at the last PCA autox of the season this Saturday actually.

You know how it is though, I'm a power junkie. With my last car (a turbocharged RX-8 making 320 rwhp) I thought 300 whp was all I'd ever need, then 400 whp was all I'd need... now I'm thinking 500... the pit goes onwards. I'm not inclined to build my motor right now because it only has 38k miles on it, and the car drives immaculately with no drama or problems, but the thought of trashing my clean 4g63 block has made me at least consider it.

 

If you wanna keep it cheap I would just put rods and pistons in the motor you have and then switch to E85. This way you can let the turbo do its thing and its all good. That turbo with a 2.3 is super responsive which might not be a good thing for track racing. You would have to learn the engine all over again. If you are comfortable with the powercurve you have now and just want a little more everywhere then ^^ is the cheapest way to get 500whp or close to it. add a good intake manifold and you should make 500 for sure. On a DJ.....

 

e85 is cheap race gas. You will be fine on your set up with that turbo. I had the fp red and fp black and e85 with a stock block. With a good tuner you should have no problems.

Oh yea and 500 gets boring quick to. I am not sure 700 will ever get boring but it might.

 

I would switch to E85 for sure no matter what.

#1 higher octane always wins vs heat soak
#2 lower EGT is easier on parts and the cooling system

The main focus on switching motor size is RPM based. The tracks you run are you normally in the 140 (8500 in 4th for most cars) range where revving out 4th would be better than shifting to 5th? How much torque can you use coming out of corners? Is more going to help or hinder?

Luke road races (I dont really, I watch and tinker) with a 2.4 just fine. At Portland though the front straight he needs to grab 5th because of the RPM limit. Cure is changing the FD which is currently in the car but waiting some dry weather and a track. The feel on the street is longer legged in 1st and 2nd and then it feels more less like driving in a gear higher than you are.

I drive in "Germany" alot so what I do is different than normal road racing. I am always in 5th revved out if the track allows but it varies enough that its nothing I can really ever predict. Most of the driving is under 140 though so the long rod 2.4, my tire height, and stock gearing (VIII 4th but stock final drive) all allow me to do that with my rev limit at 8700.

Just some food for thought.

Aaron

 

John when do you drive in germany? Everthing about setting up some tuning?

 

Hehe I'm assuming he means on his personal, closed-course test track. I get tired of using mine, maybe Aaron will let me use his one day Assuming does make an *** out of me sometimes though

 

Note "germany" is in quotes In Arron's post. Hahahahaha

 

Wong,

I will literally travel anywhere in the world to tune cars and would love to plan a trip. I wasnt referring to the real germany when I posted, as GSRboi pointed out I called it "Germany" for a reason. My german is rusty and I havent used it since high school though.

Jeremy,

You can use my test course any time you get the 2.4 in.

Aaron

 

I agree on doing on E85 now. It is so much fun and makes the car a lot more enjoyable imo. The cooling effects, the higher octane. It smells awesome too with an open exhaust. Man I miss that stuff.....