aftermarket twin turbo
 

hey ive been planning on doing a single turbo now for a while, but one of my friends over at stillen (a fellow 3rd gen owner) made the suggestion of being unique and going TT instead. i had my heart set on a gt35/40 but hes made me rethink everything. the only TT aftermarket X7 ive seen was that orange SX one. and from what i remember that was all custom work on the pipes and manifolds. my friend however claimes that he can get his hands on a twin turbo manifold, a very rare unit, produced by RE Amemiya, and then bolt up an hks twin gt 25/30 kit to it. he claims its feasible and that the manifold will cost 1700 bucks, and that he can get his hands on it fairly quickly. He does have a lot of hook ups with over seas exporters/importers, and one of his best friends is a very big player in this field. i dunno just a thought, an expensive one, but it might be something worth looking into. just wanted to see what you guys think. thanks guys.

son.........hook it up

go for it!!!!!!!!!

let us know

i am in the same boat i have a turbonetics ts04 and was going to make a single manifold for it my self but then if i sell the ts04 i can get 2 t3/t4 hybrids and go twin.

would you use a custom manifold and downpipe combo?

Checkpoint beat you to it
 

At Checkpoint we have just finished a twin gt35/40 setup that is going on my car with a custom welded stock manifold and machined housings. The motor is also being rebuilt. If it works this will be marketed in kit form.

Of course, if you want to, you should still try with your idea - more options for the enthusiast to try!

Beast

Hi Beast from the East,

You've got my attention. Where or who is Checkpoint? When do you think you will begin building boost and actually hit full boost with that setup? Any pictures yet? More info please :).--Tommy

hey all..

glad to see more people going the way of the twins..hehe

I have the m2 set which is basically two garrett gt30 ballistics...on a stock housing.

the stock housing limits how much you can push thru in terms of flow...m2 had previously ran the larger turbos (gt35's)...apparently you wont get to take advantage of the size issue if you dont machine out the exhaust manifold.....the problem lies in the fact that the exhaust manifold already cracks with high heat...a thinner machined out housing is too delicate for reliability....

Im very happy with the m2 set...they are a bit pricey but have been completely worth it....(i hate lag and a single turbo would give me that..too much of it)...the garretts also handle much higher boost than the stockers...whether that be the above set or the m2 set.

Im interested in seeing checkpoints setup..or hearing about it...what did you do differently. is it the entire turbo or just the guts? what did you do to the manifold to let the turbos flow through to their potential? I ask cuz I think those garrets are worth over 500hp each right??...but the stock manifold limits the flow to around a max of 400-405 hp..

just wondering

j

i'm interested.. though i have plenty of time until my twins go since they are fairly new.. i'm always in the mood to hear about adding more horsepower :)

Re: Checkpoint beat you to it
 

hey you guys at checkpoint are over in city of industry right? i know these two guys, jeff and leo (brothers), and i think their sister's boyfriend either runs checkpoint, or works there. not quite sure what the chain of relationship is. but jeff has hooked one of my friends up, a kid with a TT supra, with some parts. i just didnt know checkpoint was a fabrication shop as well.

I just picked up my harness for my Greddy Turbo timer from Checkpoint in industry, we have an account with them. My friends cousin works there also, his name is mike.

Checkpoint's Address - more info on turbos
 

Checkpoint is on White Rock Road in Rancho Cordova, CA (part of the greater Sacramento area). They've taken down their web site and I believe they are going to revamp it.

The shop is owned by Dave and Sandy Myers. Dave was a pioneer in rotary development in the 70s - he even consulted with GM during the development of the Corvette (GM considered putting a rotary in the 'vette, but the project never got off the ground). Their main technician is Chris Green, who is in the process of trying to buy the shop from them. Chris is picking up the torch from Dave and is a die-hard racer in drag and SCCA.

Earlier posts are right in that the exhaust manifold is the greatest challange to deal with. Chris has custom welded a second wastegate by eliminating the pre-control flapper, necessitating that this new kit will be non-sequential. That's the biggest difference between this kit and the M2 kit, and M2 has been talking with Chris and they are very interested in seeing how this new kit will work. With the second wastegate we hope to reroute the hot exhaust gases that cause exhaust manifold cracks, and with the bigger turbos we hope to lower temperatures since they won't have to work as hard to get the power levels we want.

The first unit is hopefully coming in today from the shop. I post to the Big RX7 list on this topic as well as here, so look for updates in both spots.

Beast

Checkpoint's hybrid is done!
 

All -

The first unit of the hybrid twin turbos by Checkpoint Engineering arrived from the turbo sub-contractor yesterday. While the manufacture time was much longer than expected, they are beautiful and worth the wait. The welding and porting, fit and finish are top notch, as are the materials used.

These use a similar wheel setup to the M2 unit - the compressor wheel openings are about 5/16th of an inch bigger in diameter compared to stock, and the overall length from housing to housing is longer than stock by 3/8th of an inch (which was what had been originally calculated - it's nice when a plan comes together). The exhaust wheels are smaller to encourage faster spool up, and with the ball bearing design you can actually blow (with your mouth) on the compressor wheels (with a bit of force) and the wheels will turn. The flapper door for the pre-spool has been removed and the plumbing re-welded so that the pre-spool is now the second wastegate. A shunt plate and pipe to the dp is all that is needed. The wastegate doors are set to open right at 9psi (perfectly sync'ed). The oil line entrances are modified so that the oil pressure to the ball bearings is reduced to match the oil needs of the bearings - we're probably going to replace the oil lines with braided lines and proper AN fittings. Per the manufacture, each turbo is capable of supporting 400 bhp assuming you have fuel and flow to handle it. That's 800 bhp out of twins, folks. Theoretical limits are rarely reached due to practical limits, but getting to 400 rwhp on pump gas with reasonable boost levels (~15 psi) should prove out without issue. I'm hoping for low lag and fast spool up similar to the sequential system, but will the full monty of air flow. The dyno will tell the tale.

Checkpoint will be posting pictures of the new units (with the dp attached) shortly. They are in the process of redesigning their website - I'll let everyone know when they are up. My car should be completed by late next week based on workload - we're taking it straight to the dyno for tuning. I'll post dyno results on their new site as well.

More to come......

Beast

Stop teasing!
 

What's the price?
Where's the Pics?
Where "my" set? :drool:

any updates?

beast update and pics on this motherfucker please!

You guys are too funny!
 

Ok, ok, I'm cross-posting all over on the Big List and another thread on the single turbo forum. Here's the latest:

They took pics before the install and they will put them up on a website. I don't know when and I don't know where yet. I have no influence over that.....

I have 250 miles on the car. My wideband just got finished today and I'll get that installed next week. That should work well since I'll have the needed break-in miles and I'll start dialing up the boost and tuning with the wideband for a bit, then when I get up to 12~15 psi or so I'll head over to the dyno for fine tuning and bhp numbers.

Patience, Grasshopper........

Beast

post pics of your car for now?
 

can you post the pics of the turbos on the car please also.

<-- No patience
 

Gimme, Gimme, Gimme..NOW!!! :crazy:

what was the price?

did you modify the manifold? if not you will be hard pressed to get past 400 hp. My m2s are using the garret gt30 ballistics which are rated to 400hp each as well..thats 800 hp folks...800 HP that I WILL NEVER see because of the manifold restriction. lol

just a point...good luck with the twins...Im anxious to see how you do. I should have my own dyno numbers soon as well...gotta wait for body work now that someone hit me this morning.

jason

BFTE, are these turbos going to be sequential or non-sequential? I'm curious and anxious to see some dyno numbers and a dyno chart.

Is it ready yet, is it ready yet, is it ready yet, is it ready yet, is it ready yet?
 

Their are supposed to be parallel, with a custom built manifold to overcome the heat problem that limits the M2's to 400hp. :yum:

ARE THEY READY YET :confused:

Patience, patience, patience......
 

Well, GoRacer, it's nice to see that you are paying attention to the thread (the fact that these are parallel with a moded stock manifold to overcome the heat issue). This week I will have my mandated 500 mile break-in done, and have the wideband installed. They also forgot to charge my a/c. One thing that I"m a bit excited about is that my a/c now works on all settings with my PFC! I'm wondering if the new engine wiring harness has either different and/or better wiring that overcomes the issue that the PFC's have with the a/c system.

Price - still unknown, but it won't be cheap. If you have to ask ...... well, you know how the saying goes.

How do you think I feel? Hell, I'm running around with potentially 500bhp and can't tap into it. However, time, patience, and perseverance will accomplish all things....

Couldn't you port and pollish (to a small degree) or extrude hone your manifold for more power???
How about having a custom manifold made???

Maybe a custom manifold was made...anywho, why not slap 2 gt35/40 garrett turbos in there and get a little raunchier? I'm getting hungry just thinking about it.

EDIT: Whoops, thought you were talking about Beast's car glass man :p:.

i can only imagine the crazy turbo lag on twin 35/40s! mine comes in this week, i think ill be happy with just one :P. but then again you know me...simple taste...haha yeaaaaah. any how the biggest ive seen twins get on an rx-7 are hks 30/37s and that job was a completely custom fabricated. i talked to SP engineering about it, and they said the customer paid over $2000 just for the exhaust manifold!

you can port the manifold...however the thinner the manifold the more delicate it is....those things crack to bits as it is.

m2 used to run the gt35s on their twins...it was laggier and the peak power was very similar due to the manifold restrictions.

j

Why doesn't someone simply build a set of turbos with bigger a manifold? I'm sure someone could build a set of sequentials that are larger... it's all about how much you want to spend right?

You asked for it - first drive under boost
 

All -

I completed the 500 mile break-in period and had the wideband installed yesterday. When I picked it up from the shop all they could say was 'this car was fast, now it's stupid fast'. So with high hopes I headed out for some long stretches of road and prepared to have my first forays into boost. I wanted to start off slow, so I turned my controller all the way down which limits boost to about 7 lbs. I began jumping in and out of boost up to about 4 lbs just to see what my wideband revealed. Instant, accurate feedback is one of the most joyous things a person can get - my wideband revealed that I had a lean tip-in problem when going into boost, both under light load as well as under hard acceleration at a wide variety of rpms. As I went into boost I had afrs of 15:1 to 13:1, jumping as high as 16:1 under hard wot. I upped my maps for the PFC in x10 and x11 columns and the y10 - y12 rows from the high hundred-teens's to the low to mid hundred-twenties for fuel correction, then upped my accelerator enrichment settings in the
2000 - 5000 rpm settings from ~7.5ms to 8.2ms, and my tip-ins dropped to afr of 13:1 to 12:1. Now I went to 7lbs. My afrs stayed around 12:1. It was
a very hot day (over 100 F) so I wanted to stay around 11:1. I upped my middle-boost maps about 6 'clicks' in each cell (that area IS denoted by the coordinates 12,11-20 through 15, 11-20, so that those went from the mid to high 120's to low to mid 130's. Now my afr's looked better. In anticipation of going up in boost, I took the time to adjust the maps in the 15,15 and up coordinates by about 6 'clicks' as well.

At this minimal boost setting, the car felt about the same as it did when I had the stock turbos on it set to 14lbs. Frankly I was amazed. They did spool up a bit slower than stock, but being non-sequential the lack of
turbo transition made up for it. Also, these turbos are quiet - in some ways that's disappointing because I always enjoyed hearing the pre-spool noise of the stockers in the dp through the firewall. These make absolutely no noise - just a steady push of power.

The time had come to turn up the wick. I went to 12lbs.....

There are not enough superlatives in the English language to describe the mind-bending, tire-melting, asphalt-eating adrenaline rush that 12lbs. represented. 110mph came so fast I was startled and scared. I've not
experienced torque-steer from a rear end breaking loose in third gear at 80mph under wot. Whoa. I did that a couple of more times to get used to it. The very small lag was more than made up for as it jumped from 7 to 12 lbs in a heartbeat. The elimination of the turbo transition really improves driveability under wot. I took a look at my charge temps - NOT ONE DEGREE OF CHANGE! I started at 60 degrees C and ended at 60 degrees C. The improved flow is really amazing.

Under no boost in 3rd gear I did a rolling wot start from 40mph to 110mph. I counted off 7 seconds of elapsed time (remember, I started at a steady
cruise with no boost), and the car just wants to run and run and run. At this boost level the bov finally made some noise when I upshifted to fourth. The Bosch unit isn't very loud - it sounded like someone breathing
hard after running up a flight of stairs. My afr's at this boost were 10.5~10.7, which was fine by me. My injector duty cycle was only running around 59%, and my maps above that can still correct from the mid 130s to 149, so it looks like the Nippondenso fuel pump and 1300cc secondary injectors (RC Engineering got them flowing to 1350cc) can keep up with the fuel needs of the car.

As I went home I did some drag type starts from stoplights. If you shift before 7K rpm you just miss the beginning of the power band in the next gear. When shifting at 7.3K the revs drop to 4K and you are right at the beginning of the sweet spot. 4K to 7K is Mr. Toad's Wild Ride.

I am now in the process of slowly dialing up to 15 lbs, where I will probably stay as a base line to get track and dyno numbers. I know that anyone can describe what 'fast' is - I now need empirical data to back up
this discourse. We also might bump up the timing a bit in the low boost areas to see if we can get rid of what little lag there is in that area.

I'm thinking of heading to Sac raceway on Wednesday 21st. If I can't make that due to work, then the next soonest time I have available would be an autocross on the 25th or sometime early in September.

Oh, and for all you PFC users with the intermittent A/C problem - replace your engine harness. Maybe the design was improved since '93 or maybe my old harness was just that - old and heat-baked (and therefore not as conductive), I don't know. One thing I do know is the new harness has fixed the A/C intermittent engagement issue for my car. I now blow cold and constant at all fan settings. This was a total bonus.

I will publish any timeslips and dyno numbers I get over the next few weeks. Checkpoint still does not have their website up, so there are no pictures yet available of this new unit. However, because it looks so stock, don't expect to see the same kind of dramatic visual presentation that you get when looking at a single-turbo car. That's the beauty of this setup for we Kalifornians in pursuit of ludicrous speed!

Beast

Border Racing also makes a twin Apexi ball bearing kit. 500 ps at the wheels.

WOW, really??? Any more info, links, specs, price, etc...

http://border-racing.com/main/border...turbineKIT.jpg

$3,830.00 USD

OMG Beast gorgeous :eek:! Thanks for the heads up man regarding the condition of your twins! So you live in Cally, that's great...heheh. Twins are, as you say, the best way to look stock and still pass emissions. Speaking of which, are they capable of passing emissions? Oh wait durr yeah......turn boost to 0 ;). You didn't hear me say that...heheh. Congrats man and I hope to hear alot more about your setup in the near future as well as check out your time and dyno slips :).

EDIT: Damn Boostd7, that's beautiful. I wonder how those babies fare up. Where can those be purchased at? Them Apexi bb turbo kits?

The turbos are Apexi IHI AX53B70-P25 units similar to the RX6 (smaller though, the FD3S RX6 is a TCW76-P27). The CHRA is dual ball bearing design, and is water & oil cooled. Stainless manifold and downpipe, all fittings and coolant lines. Internal wastegates.

Wow, so it run in parallel, I wonder what the lag is like on that. Thats a damn good price too, I'm interested.
:eek:
:bowdown:
:mspank:

Go for it glass man. Always good to see some peeps take the challenge. Dman turbo kits popping up all over the place. All us TT lovers would love to put them balls under our hood :D.

Yeah they run parallel. I posted the info on these awhile ago, but everyone was pretty skeptical of the 500 ps figure. I haven't found any dyno numbers for an FD with this setup, but the Apexi drag Integra uses twin (smaller than the Border kit) Apexi IHI AX53B70-P21 turbos on an H22A, and produces over 650 bhp at 22.8 psi.

Wow that's insane boostd :eek:. Yea there's gotta be one happy soul on these forums that have this setup. I vouch for a TT subforum to be open up :D.
/me raises hand

What ever it is, I see Balls in my future. :D

If you are serious glass dude I can get you in contact with a couple people who can get this kit.

As long as they are good friends with my friends, American Express, and Mr. Visa and Mastercard. :)
I'm also looking into the M2 dual BB and the GT3540 kit, as well as the regular Apex'i kit. Since the Apex kit isn't water cooled its kind of the bottom of the list.

Well, out of those choices I would (me personally) choose between the Border kit and the GT3540. Speaking of power I think the Border kit has a little more potential, but the GT3540 is really close behind that.

Yea if only my stupid RX-7 deal didn't fall through! POS!!! Well in any case, I will keep you guys in mind when the time comes :). And believe me, the time will come :D. The border kit is pretty badass, but is there any US distrubitor? Plus Beast, or anybody who knows, know when the tt 35/40 kit will be available? And the price? I know you mentioned that...
But let's get a precise number shall we :D?

For sale: 1 kidney for Border twins
 

:drool: Two are allways better than one:titty:
Damn, that pic is centerfold material!
:mspank: :mspank:

that is a fantastic price for all that....someone buy it!! and then dyno it!!


j

How much would it cost in japan? Would it be cheaper to have someone pick up a kit and bring it back?

Heading to drags this Wednesday
 

I will be out at Sacramento Raceway for the Street Legal drags. We'll see what kind of numbers I can lay down.

Beast

hehe dont we all wish...
 

the actual price for the turbo kit from Border, WITH TURBOS is 750,000 Yen or $6355.00 at current exchange rates . I estimated at being able to offer this kit at $7500-8000 to your door with freight and insurance and duties, bank fees and all that crap

the 450,000 yen price is a setup kit - No turbochargers

keep in mind this kit requires removing the smog pump and EGR I would think

AND you will need a complete fuel system to get anywhere near the potential.

AND does not include any piping for the intercooler...

Or an intercooler...

I was going to get one for my car, but I think I could build a custom internally gated T3/T4 kit, cheaper.