Rx-7heaven

iTrader: (1)

I'm looking to build a motor between 350-500 bhp. Possibly turbo'd. My choice is to use a 6 port n/a s4 block and part together a motor using s5 and s4 parts or just go for a s6 motor (fd short block). I already have two s4 6 ports tore down and ready for work and to be put back together. I have a buget but look to be buying stuff over the next year or two. I'm looking to run a standalone.

What would you guys suggest I use to gain that power?
I know 400 is possible n/a but huge mods needed and mainly are only track cars due to durability. I'm looking for power but also streetable.

If I was to turbo a block, would a street ported s4 6port spin a hx35 turbo? I have one that could be used if so.

TIIFC3S

If you haven't already, I'd start by spending some time on Aaroncakes' site, as it has a ton of info for 6 port turbo builds. He went bridgeport, but there should be plenty of useful information on there to get you the numbers you want. He also has some videos on his youtube page.

http://www.aaroncake.net/rx-7/

http://www.youtube.com/user/aaroncake#p/a

arghx

iTrader: (3)

how much money do you have? Be realistic.

Rx-7heaven

iTrader: (1)

I've already done the reasearch on his site and he does have some really good info there. I'll be looking to spend around 2-3k to build the motor and 1300 on standalone. that doesnt include everything else. Over the next few years Ill be looking at about 5-7k into this build.

Furb

iTrader: (2)

that is NOT going to cut it.. you need a bigger budget for 400hp if you want it to last longer then a week

Rx-7heaven

iTrader: (1)

and what is it your speaking for price range? What parts should I look for?

joeylyrech

iTrader: (11)

To many variables.............................If you look in the right places,know the right people and do your own machine,fab work 10Gs will do it.

Brodie121

iTrader: (8)

between 350-500 bhp. Possibly turbo'd

possibly is not an option...

you will not make that non-turbo...

canonize-ryda

wow for 5 grand i can buy a fc rx7 with a 20b engine.. u freaking serious 10k? all on your own.
i mean ive seen fd rx7 modded go for less than that. one just sold here at a dealer for 4k. and he has probally most everything sep a big turbo, the street port, ems, fuel injectors, intercooler and piping, turbo exhuast mani, port matched, well now it seem more like 10k....
but still 10k can buy a pretty sweet ride these days(if all the works already done though)
I seen that too when he said maybe turbo, NAs are crap power but a high compression turbo setup like arrons will make 400 over without loads of doe....

joeylyrech

iTrader: (11)

That is what is sad about it,i have around 10Gs on my own FC(turbo alone was over 2 grand)and if i get 5000 grand for it will be a miracle.
Aaron does have a lot of money invested on TINA,everything on that car is top on the line but he did all the fab work.

bumpstart

from that list of starter parts ,, my formula would run something like this---

s4T primary ( late close mild ported )
6p endplates ( stock )
keep inlet open port timing fully captive of the side seals

large exhaust ports with minimal increased overlap

goopy apex seals ( or mazda if you have a great tuner )

goopy through bolt system

modded t2 LIM to suit, t04/66 with 1.32 and 50 mm external gate

external FPR ( sard )

4 x 1000 cc injectors parallel rail fuel system
or alternatively 2 x 550 and 2 x 1600 cc injectors if you dont mind a staging bump

2 x walbro 255 LPH
or 2 x 044 255 LPH pumps run from the battery via fused relays
( switch the second pump with the ECU aux out at 2 psi boost )

decent ECU as a minimum,, ( haltech PS 1000 )

decent HEI system like 4 x LS1 or LS2 coils

bar and plate style indy /china cooler
( these have minimal pressure drop ,, but a large cooler is required to be thermally efficient )

a decent tune !


at 1 bar boost this will trip an easy 400 rwhp on a DD dyno
,, which is more like 450 rwhp on some of your dynos
at 1.5 bar boost this will make 500 rwhp on an US dyno
note the 4 x 1000 cc fuel system at stock base pressures will find limits around 450 rwhp ( dyno type depending )
and may require a 50 psi base pressure if looking for higher power

joeylyrech

iTrader: (11)

Why that big of a hotside with a mildy ported block?

bumpstart

to achieve 400-500 rwhp reliably and not have a 3 or 4 to 1 backpressure ratio !!!

cause when you flow 500 HP worth of air in,, you have to get 500 hp worth of exhaust out

smaller turbine volute will amount to cooking and choking the **** out of it at higher airflows

1.0 is choking most motors by 300 rwhp
1.15 is good to around 400 before it gets restrictive ,, 500 obviously wants something a bit bigger ,, yes?


and BTW,, i have plenty of experience with 6p turbo-- i have done more of them than most since the mid 90's ,, with evolution in steps

i also have a few setups around with 4 x 1000 cc injectors and duel switched pumps
others with 690 x 2 and 1600 x 2 fuel setup
and also with t04/66 's in various guises

Black Knight RX7 FC3S

iTrader: (7)

You can get 400 HP under 10k, possibly around 6-7k if you do all the work yourself and just buy parts. 400 hp on a 6 port block seems to be a waste of money really because the exhaust inserts are a bitch to get off, most people just buy turbo housings instead, which are already $1200 for two. For a reliable 400hp, its better to start off with new housings. Then theres the choices between apex seals, redoweling the block, and such. Also, from the past, many people turboing a S4 block, at around 400hp, the rear iron cracks if I remembered

Also, I dont even think the hx35 will get 400hp, or atleast struggle to get 400hp. The wheel is a bit small, both the 8 and 7 blade hx35 is smaller then a to4e 60 trim. A to4e can reach 400rwhp at 20 psi but its pushing the effeciency too much. A GT35R is a better suited turbo for 400hp+

on a turbo engine, reducing the overlap is what you should aim for when porting, never port upwards on the exhaust port.

Rx-7heaven

iTrader: (1)

Now if anyone can tell me what type of power a s4 6 port irons could hold up to that'd be great. I'm thinking if there not going to be at least strong enough to hold between 350-400 I may just switch my blocks to something else... But sense I already have them I was hoping I would be able to use what I had.

What are so local places on the east coast for lapping irons?

Bumpstart Now are there anyother apex seals that anyone would recommend other than goopy's? I haven't heard much about them.....

Also, for the LIM I was thinking of using the 6 port to s5 tII conversion peice from japan2la. He machined a lim to convert from 6port LIM to s5 TII UIM. What are your guys opions on those?

87 t-66

iTrader: (133)

Aaron Cake

iTrader: (1)

There is a big difference between 350HP and 500HP. 350HP is at the edge of what you can accomplish with a stock block, hybrid stock turbo and an RTek. 500HP is a full standalone, full turbo upgrade, and a well built engine.

It's going to be turbocharged, unless you intend to build a peripheral ported 13B and spin it at 12,000 RPM, or a big bridgeported 20B, or a 4 rotor, etc. Or a lot of naaaaaaaawwwwwwzzzzzzzzz.

Just get an S5 TII engine and port it. Or, if you want to swap engines, an REW or Cosmo 13B and run single turbo.

Good reliable 400HP:

-S4/S5 TII block, street port
-standalone of your choice
-720CC pri/1600CC sec
-GT35R .90/.96 divided
-nice intercooler
-appropriate exhaust
-Walbro 255 fuel pump
-misc other supporting stuff

Irons tend to crack via tuning problems and/or ignition noise. But if you have the choice, why not go with stronger irons as opposed to what you just have sitting around?

Stock and Atkins (in that order) are probably the most widely used.

Or do it yourself. http://www.aaroncake.net/rx-7/4PortLIMTo6Port.htm . But this is only necessary if you have a 6 port block.

Rob XX 7

iTrader: (8)

Ill take 2 please

Rx-7heaven

iTrader: (1)

Alright If anyone gives anyone **** I will ask to have there post either deleted or have forum closed.....I wanted info not spam or flaming!

Rx-7heaven

iTrader: (1)

Thanks Aaron, But I have also read and understood by many people that that s4 n/a and s4 TII block are the same except for ports and compression ratios on rotors. (speaking of core only no intakes or accessories...) I also believe I remember reading that the tII rotors and n/a rotors have slight changes through weight. Now I do understand that if I wanted to spin past 8g on tack I would need to at least go with s5 rotors. Now how would scalped rotors effect a build cause I've been reading on that and I'm looking to make something with power but reliable. Now I know that I probably should take the time and talk to the guy in charge of CLR motorsports but would you guys think it to be worth doing the scalped rotors for the benefits it has?

13B Etc

iTrader: (2)

But almost all of what canonize had to say -was- spam...

canonize-ryda

i was saying it would be cheaper to purchase 350 hp setup than too dump 10gs into a 2000 dollar car.
i myself want to make 300 plus hp but would never dump 10gs into it unless i had like an extra 100gs somwhere else.
a 20b for 5k is bs? depends where you live. but ill admit it was 10gs for it not 5. so yea a little bs on my part. sorry

pokemonpimp55

iTrader: (6)

I make 420hp all day on low boost, here is an idea for power to price ratio...
-cxracing front mount $400
-750cc/1200cc $380
-walbro 255 direct drop in $100
-fuel pressure regulator $100 himniracing.com
- rotaryworks exhaust manifold $200 borgewarner s366 t4 turbo $700
-custom down pipe with exhaust -$600
-bov anywhere from 150-500$ your choice
-microtech lt10 ecu from cft.com $1020 ask for rolo lopez! !!
ne than the kicker, what engine are you going to drop in? S5? S4? Leaving an engine on stock ports is going to limit its flow, I have personaly made 372hp on 16psi with stock ports, and the engine is still with me till this day, also take in consideration tuning prices with the aftermarket ecu, not worth losing a $4000 engine over amateur tuning!!!

Black Knight RX7 FC3S

iTrader: (7)

I was thinking about the rotary works manifold.
How good is it? You have the FD or the FC version

Aaron Cake

iTrader: (1)

Correct, but that is kind of like saying that Justin Bieber is the same as Lindsey Lohan except one is a chick (although it looks like both?).

Porting radically changes the characteristic of any rotary. For example, running a 6 port block with the aux ports wide open as is done in most 6 port turbo setups (including my own) results in a big loss of low end torque unless the massive port area is compensated for (ie. custom intake and tuning). My current turbo 6 port setup I am building for my Cosmo has fully working aux port actuators.

Honestly, it is easiest to just start with the TII block if you are looking at ~350HP because just a street port will get you there with appropriate supporting mods (turbo, etc.) without needing the huge port area of the 6 port block.

http://www.mazdatrix.com/faq/rotorwgt.htm

No. Scalloping rotors opens the intake ports earlier in the same way that moving the port towards the housing does. Not necessary for your power level.

Your list is great except for that ECU. To anyone reading, I'd suggest a modern ECU that supports things like configurable I/O, save to disk, 3D timing tables and closed loop O2.