shm21284

OK, I got the car running, engine broken in, and I G-Teched it last night with and without the alcohol injection. In case anyone doesnt know, heres what I have:

Rebuilt, street ported 12A with Atkins apex seals
TII flywheel, tranny, Exceddy clutch
BAE turbo kit with a RAYJAY B trim turbo and .86 A/R on the exhaust side (its a drawthrough turbo setup)
Carter AFB carburetor
Alcohol injection
GSL rear end
Holley RED fuel pump
And a bunch of other goodies not concerning power.

I made 202 RWHP with a G Tech in 3rd gear at 7500 RPM. GTECH's DONT TAKE IN ACCOUNT AERODYNAMIC DRAG!!!!! I think this number will be closer to 220 RWHP on a Dyno. Anyway, with a 20% drivetrain loss, that translates to 255 BHP and 275 BHP, respectively. This was at 15psi and NO alcohol injection.

I made 180 RWHP WITH the alcohol injection. With alky injection, I only got it to boost 13psi. It runs WAY too rich with the injection and therefore is not spooling the turbo as fast. I have a boost controller, but I got tired and my car is loud, so i didnt want to attract police.

Also, my fuel pump is acting up. I need to buy a new one, bc the one i bought was badly rebuilt. It still is cutting out in 4th gear, which i only did once bc i dont want to break my engine from detonation. I tested flow, and its flowing about half of what it should.

Conclusion: I met my goal of HP, but whats even cooler is i did it WITHOUT the alcohol injection. When i buy a smaller injector nozzle so it will be the correct amount of alcohol injected into the engine, then it should make more power. I may just do water injection instead, but i am not sure. Also, I will be able to complete a 1/4 mile when i buy the new fuel pump. Anyway, thats the car. Most of you saw the pictures of the engine before.

coldy13

Nice, making pretty good power. I wonder how much more it would make with the same setup converted to blow through. I'm having problems with fuel delivery now too. I put a HUGE main jet in my carb, and it still runs lean at the top of 3rd, so now I know for sure it's fuel delivery. I'm gonna try using the tank drain plug as the fuel pickup, that should help a lot. If it still starves for fuel then I'll just make new lines, probably 1/2".

CarlRx7

if your running lean up top then its the main AIR bleed jet, try taking it out and retry to see if the top end is pig rich.

carl.

shm21284

technically, i should make more power with this setup and a working alcohol injection system than a blowthrough, intercooled system. Alcohol/water injection is way more efficient than any intercooler is. I will get my car dynoed and then design the alcohol injection around the power curve.

coldy13

It runs good through gears 1 and 2, doesn't run lean at all until 3rd gear, which means it's not getting enough fuel to the carb.

shm21284

sometimes first and second gear go so fast, a slight change in fuel metering, timing, etc cant be noticed until third gear. When GTORX7 had his silver FB with intake, exhaust, and NOS, it worked fine until he hit third gear, when it started detonating from lack of timing retard. Just some food for thought

2wankel

iTrader: (1)

Sorry for off topic, but what body kit is that on the red car.

coldy13

I was thinking it could be that too, but it detonates at the exact same RPM with the 200 jet as it does with the 235 jet, which makes me think it's fuel delivery. What I don't get, is that I'm running the exact same fuel setup as I was with the nikki. With that setup I could rev it out to 8k in 5th with no sign of detonation at 16psi. But now I starve for fuel at 5.5k in 3rd at 6psi?

Here's the thread about my new setup, with pics : https://www.rx7club.com/1st-generation-specific-1979-1985-18/finally-new-pics-338368/

coldy13

It'll probably be about the same really. You gain efficiency by using alcohol/water injection instead of an IC, but you lose a bit by sucking the fuel through the turbo.

nevarmore

Since you're in Ohio (I know Alexandria is in the middle of nowhere), go to ColumbusRacing.com, pop into the Speed Shop/Vendors area and find the post from Mobile Chassis Dyno. Brian is a nice guy and will do dyno pulls for ColumbusRacing board members for dirt cheap. It'll cost you less than half of what that G-Tech did for 3 pulls.

Sounds like you have a really nice set-up. Pics??

Directfreak

iTrader: (2)

That's the problem with Webers/Dellortos/sidedrafts with a blow-through.
The Fuel bowls are too small for a complete three-gear run at WOT.

The way I've compensation for it is to run a small injector with an AIC.

Directfreak

iTrader: (2)

I think you're being optomistic. The G-Tech is a great tool to see differences of
before and after modifications. Better than any "seat of the pants" dyno.

It is not accurate to calculate Real world horespower. Have you had your car weighed recently?

Those calculations make big differences as well.

I have a G-Tech Pro myself, and love it, but it is wayy to easy to get incorrect numbers.

Try either a real Dyno, or horsepower calucaltions based on 1/4 mile PER HOUR (at the end of the track) and weight.

Let us know when you get updated numbers.

http://www.dsm.org/tools/calchp.htm

FB II

what? are you serious? ah man. crap this is not good. is this pretty much the case for all of them???

680RWHP12A

not true, the float bowl are huge, plenty big enough... the rest of the fuel system must be addressed.... the carb needs to get fuel to work properly

Rex4Life

Are you running with TII rotors also? Reason I ask is cause I thought the TII flywheel was balanced with the TII rotors--so if you still have the 12a rotors you may have a balance problem.

That alcohol water injection sounds pretty neat. I wonder if the stock sub-zero injection point could be used for this--otherwise the sub-zero stuff is useless?

Scott

REVHED

Bingo. I've even seen people run an EFI style surge-tank setup to make sure the carb never has a lack of fuel.

FB II

Woot