My SBC-ID wasnt holding boost weel past 15 psi so we quit doing pulls unti I can figure out the problem. We added a Wastegate spring to put it closer to where the boost controller would be controlling the wastegate but it didnt help. The boost comes on fast as you can see once the car was tuned and the curve goes up fast. Very good power all the way through the RPM range for a big single turbo. I was pleased. And am goin back for a 17 psi pull with my new motor next month.

 

Is your boost controller the problem after 6k? The power just drops off big time from there, it shouldn't be doing that even on stock ports. The power looks like it comes on with a big rush after 3k though! Get that thing sorted out because it looks like you will make significantly more power.

 

Sweet! Your power comes on strong! You definately need to get your boost controller set-up..on the SBC-id don't use the automatic config, manually adjust the values to get your target boost.


Good luck,
Steve

 

Supra guys use that controller to 35 psi, just work on set up. Carl

 

What was different between the last two runs? both say 15psi, but you've got a 59ftlb difference in tq...

Also, do you have boost and a/f ratio graphs? cause there is a big problem above 5500rpm...

Very up to the drop, but personally I wouldn't push the car until that dropoff is taken care of.

Brian

 

Yeah the boost controller was set on Auto. I didnt have the operators manual for the boost controller when i was at the dyno so we just quit making pulls. The main reason for the difference in power between pulls with similar boost levels was it was being tuned on the dyno.Also the boost came on faster once we put back some wastegate springs. I wasnt just making pulls to see how much power I was putting down. I had to wait until my motor was broken in so it was a couple months after the install. I am goin back and doing some more pulls once I get a few items sorted out. I was happy with the power output. Its definatly one of the best street/strip turbos available in my opinion. A-spec gives great support on this kit. We will do some more pulls nest month and I will post the sheet.

 

That appears to be on the weak side? Is your motor ported?

 

Its not ported and is still having some bugs worked out. I just wanted to post the dyno sheet to show how its coming along. I was happy to see over 400hp at the wheels with alot more potential. This was the first set of pulls with my new broken in motor with about 1k miles on it.

 

In comparison to what? I am very impressed by his chart especially considering the boost problems. Look at the power and torque he's making at 3000, 4500 ect. I believe Ihor got similar top end numbers at the same PSI with a monster street port, but I don't remember his low end looking that good. Maybe I set my standards too low. I haven't seen too many 3540 dyno sheets but that looks pretty good to me. What are you using as a frame Mr. rx-7 TT?

Mike/zoomzoom, I'm glad to see you're getting through the teathing issues (blown motor ect ) and are finally getting some good results.

-Chris C.

 

That's good.. With two more psi you should make 425-430 rwhp and if you ever get your motor ported you should make another 30-40 rwhp at the same boost level. Good numbers.

BTW: I build motors....

 

dupe

 

BTW: Who is doing the tuning?

 

don't get me wrong, that is a lot of power... but what's going on over 5500rpm?? the thing falls flat on its face.

 

yeah the boost controller wouldnt hold the boost because I had it on the wrong setting. I didnt have the manual with me so we just quit doing pulls until we got it sorted out. I will be doing some more pulls later next month. Dave at KD Rotary did the tuning. The power drop was the boost controller cutting boost. I think I have it worked out. We shall see.

 

Hey Thanks Chris. You basically have seen this project go craddle to grave and back again. You even know about my mood swings with this car. I am happy to say its getting better as bugs are being worked out. You may be the only guy you know still with stock twins! As we all know these cars are always a work in progress. Nothing alot of money cant fix.

 

Actually I think with the boost controller holding the boost i can make 425 at 15 psi. But I am just guessing. The turbo starts to Hit its sweet spot at 15 psi and really starts to flow. As soon as I hit 15+ psi the power was going up alot faster per PSI than sub 15 psi runs. This turbo hasnt seen it potential. I think only a few of us have dynoed and tuned our cars with this turbo. As the year progresses and more people will have them tuned with different set-ups we will have a better idea what this turbo can do. I am impressed already with what I have seen. Ball bearing turbos are becoming more mainstream. I think you will see a huge falling away from standard bearing type turbos.

 

What specs does the turbo have? Do you have any new dyno graphs or horsepower figures with the boost controller worked out? The figures sound good to me but the drop off in the top end is quite severe. Is the turbo running out of flow at that rpm and boost level? It looks like it peaks and then simply falls over!

Atm, i have my 1000cc primary and 1700cc secondary injectors ready, a 45mm turbosmart wastegate, an e-boost, an ltx8s microtech and a pair of 910 bosch pumps on the way. The thing i don't have is a suitable turbo. I've seen a few things written about the GT40R and it seems like a very good turbo, although there hasn't been to much joy in the way of it's performances. If it is possible to make this sort of power on only 15psi with a 35/40, then i'll have to start taking it more seriously. The only thing is, i want a turbo that can keep up with an engine revving to 8-8.5k!

 

Looks to me that on that last run your were at more than 15.. more like 17 or 18... Once you get your boost controller working a bit better we can get some better numbers. Good job, keep us updated!

 

Switched Out turbo To R85. But the Gt35R can make 400 HP all day on pump gas. Ported or not.

 

Phtttt, you should have got one of my new TO4 divided 35R's that will be here soon oh well.

 

HAHA, Im sure it would be Kick ***. I loved the GT3540. Its Nothing against it. Just want to try something else. I would like to try an GT40R but i dont think they allow for test drives. Gotta buy it and see. I went to the R85 Kit for Simplicity. The guy who makes them Is my Mechanic for everything. Just makes it easy. Its a one stop shop.