I'm debating on going with a stud kit or use stock tension bolt? Could I use 5 long stud rather than doing the whole motor which I think is over kill? I'm running a streetport with a 76mm tubro and my goal is to reach 550-600 rwhp on pump gas (h20 injection) and around 750rwhp on race gas. Let me know how you built your motor?

 

I guess nobody care? I'm sticking to the oem tension bolt. Do you think I can get everything in the T2 running within 1 month? This is the goal I set to accomplish I know it undoable but I like to set the bar high. Going to get started on the rebuild next week. Come back within 1 month to see if I can do the impossible

 

Im doing it right now... I was running 600hp on the oem bolts

 

I considered it, but given the cost and my goal of 400HP or so I decided to stay with the OEM bolts.

 

i had additional pins installed. but we will see how it holds when i acatually get to start the motor

 

+1

 

Damn I didn't know you're going with a 20b? So who built your motor?

I haven't decide on the coils yet (remember I'm on a budget) I heard about the ls1 coil, have anyone had good luck with them? I'm trying to hit around 650rwhp on mine.

Here's the stuff I have so far:
microtech lt16 x6 ignition box
bosch 044 fuel pump ( I was told 1 is good for my hp goal) I know this is risky but let see if he's tell the truth.
1200cc primary with homemade rail
1600cc seconday with homemade rail
-8an inlet which Y out to feed both rail and -8an for fuel return
50mm wastegate (ebay)
turbonetics t76mm with .96 hotside
turbo manifold was bought off a member on this forum
4" intercooler 24"x12
streetport motor rebuilt by ME I put the 3rd gen exhaust sleeves:using RA 2mm superseal and all new seals and springs.
act clutch that hold up to 731 lb torque
lightweight flywheel
T2 tranny
coil???

What do you think about my setup so far?

 

dont risk it with the ebay wastegate.

 

I will surely will let off if the boost spike over 15psi. I'm using AI too for safety incase over boosting.

 

Hi All,
Definately stud the 20B unless NA - in that case it's really not necessary, but still a good idea. Had mine worked by Extreme Rotaries in Melbourne.
Check out the ongoing build here - https://www.rx7club.com/20b-forum-95/stewie-says-its-boy-i-say-its-fc-20b-were-both-right-though-%3D-854859/
All the best!

 

They only make oversize stud for 20B if it's a oem replacement I would just all over it. I wanted to replace the 12mm onces. I'm going to go with the stock oem and rely on AI and tuning to try to get my goal 650rwhp.

 

Okay, going to be blunt here. The advice you're getting is questionable at best. With your best interests at heart:

Dump the cheap wastegate. You'll regret it and it will cost you a bomb in the long run.

There is no way in hell that a single 044 will give you what power you're asking for. Even if you have a large surge tank. The first time you open it up on the highway for more than a minute your surge will be empty and your engine will go bang. Don't suck it and see - any lean out will destroy your engine. Hell of a way to test a theory. Get two. Don't think about it. Just do it.

With the power you are aiming for, the standard bolts will not cut it. It's well documented in drag circles that the twisting force will exceed the stock bolts. First there will be leaks you won't be able to stop, then worse. Get a stud kit from Extreme or somewhere more local. You'll need to open up the holes 2 mil (as the studs are larger as well as stronger).

If you don't have the funds to go in this direction, lower your boost to 10psi. You'll still have a hell of a lot of fun, but your engine won't be in extreme risk. I'd still dump the ebay gate. I had one on my 13b - and even though I polished the sleeve with wet and dry for an hour, it became jerky in operation after a month. Then it jamed closed without warning. I was lucky as I wasn't running a lot of boost - and I have spare 13b engines. Don't risk it on a 20b.

 

defenitly go with a oversized stud kit link to rotary online were mazdatrix uses the same ones but sells them for more.
http://www.rotaryonline.com.au/store...636cf4c4abd399

Also do not add extra pins to your 20B with high boost the irons will crack since the wall on the irons are thin. Do your research before buying and building the 20B.

 

Thanks,I will keep you updated on the built so starting next week I'm going to try to get the car running within a month.

 

I like your avitar James. Lol

 

Well good news I found out rotary-works have the titianium stud kit for stock replacement bolt for $600. Just order the stud so nowmy new goal is to reach around around 800rwhp

 

can u remove and replace the studs one at a time? or will u have to rebuild the engine if u do that?

(assuming u have a motor thats already closed and not in pieces waiting to get assembled)

 

It could be done with some trick but I wouldn't do it cause the oem seal will shatter when dentonate. My motor was suppose to be 100+psi on all the rotor and was guarantee for 30days after being installed. When I open it up I found the rear housing has some scatches.

 

Its never that easy, especially in the high rpms. 30psi will come in a heartbeat.

 

Look, up in the sky, it's a bird, it's a plane, no - it's the remnance of your engine shooting through the air... You're asking for too much without doing enough to stop it going skywards. 800 rwhp is massive even for a 20B. What's the plan for the car when finished?

 

Let see if my built will hold up to the massive hp? Here's how much I got into this project so far:

90 T2 roller $1450
built motor with all new springs and seals + titanium stud kit $4200
microtech lt16 $1400 no coil haven't decide yet but leaning toward ls1 coil or msd blaster
fuel system 1200cc,1600cc,custom primary & secondary rail,a1000 fpr,-8an lines,bosch 044 fp $1000
motor mount $150
act clutch $420 On sale holds 730lb torque (haven't came yet)
lightweight flywheel $110
Rotary-works 20 TB $350ish (still pending on group buy)
ebay 4" intercooler $200
ebay wategate $100 (
76mm turbo T4 with manifold $1400
$600 in custom dp and intercooler piping

My plan is to get it running within a month.

 

+1 on dumping the eBay wastegate. Just saw one of those in action at Kilo Racing and what a POS. They had to grind down the valve area so it properly seated and then it cracked at the flange. Total waste of time, especially on such a critical part. I run the 50mm Synapse wastegate which is essentially a 60mm unit and it works great. High quality stuff without a rubber diaphragm.

I woud also recommend the Guru stud kit. I have it and no problems. I don't think the Ls1 coils will work for you above 15 psi without some sort of ignition boost. I took those off for the MSD blaster ss coils and they work great. A lot of guys don't like them but no issues for me.

 

Thank you David for your post, I'm now going with the msd blaster.

 

Now get rid of that crappy eBay wastegate and my work is done

 

I second that emotion

Please, rethink a few things. Firstly, I'm going to go so far as to say "You can't build a big HP 20B on a budget". I mean no offense, and sincerely have your engines best interests at heart. Go the Synapse for sure. Go the Guru stud kit (for 800rwhp - god you'll need it - seriously!). Balance and gap your rotors. Work the oil channels. Get a second 044 - ONE IS NOT ENOUGH FOR YOUR HP. Hell, for 800rwhp I'd consider 3. Remember they are rated at 500+/- HP each. Take 15% off for safe keeping, and you can see one will never be enough - two is a grey area. How big is your intercooler? What have you done re oil cooler? Need a big one for sure. Radiator needs to be the biggest cross flow you can fit in the car. Is the clutch a double or triple plate? Double is good for 800rwhp, Triple is better. If a drag car, triple is the go. You will destroy a double with too few big dumps. T4 turbo? I thought a T4 was good for up to around 650-700HP? Have you looked into your turbo's efficiency range? A turbo that is used beyond its efficiency range will become restrictive at high boost and flow levels. In a word it will be inefficient and will not give you what you want. Please look into this and cast an eye over the gt88 from Garrett - or I have heard great things about the 80 also. Can't remember who makes the gt47 - don't think it's Garrett. Also have a look at billetturbochargers.com. They are not local to you, but do make great turbo chargers - just remember to use a pressure / flow restrictor on the line into the oil cooling section - otherwise oil water contamination is possible on high oil psi as you exceed the tolerances of the coolant channels within the turbo - a 50psi limiter is recommended. A 20B turbo with manifold is massively cheap at $1400. My 20B turbo alone was over 3K - and my HP goals are less than yours. Does the manifold match your increased exhaust port size? Have they been opened up? If not your goal is virtually out of reach before you even start. Has your intake been flow balanced? The greater the HP, the more this is needed - and you are after a lot of HP. How hard are you planning to rev this engine? 20B's can take a lot of revs IF the oil is there all the time, and you plan to rebuild fairly often. If not, limit to 8 or 8.5. You'll still make big big power, but it's life will be extended greatly.

These are just the things I can think of off the top of my head. Please understand, I WANT you to succeed in your goal. But I want your engine to last long enough for you to enjoy it.

Have a flick through my thread (the link is above), and look at what I've done and why. There's a lot of useful info in there (compilation of lots of professional input - as well as massive support and info from this site.)

In any regard, I wish you all the best for your build!