RB25DET...Pretty Much Complete...Last concern

[SillyRB]

The Motor is ready (RB25DET, Microtech, HKS Exhaust Manifold, Solid Motor Mounts, 1.2 mm Head gasket, ARP Head Studs Polished and port matched head, RPS 6-puck clutch, PT67 turbo and a few other goodies.The motor is in the car right now. About to be in the process of being wired.It has been in the car before, I sold my stock wire harness and ECU and i am going with a microtech. I already have the microtech (LT-12) Model and i am using stock coils.I know my coils are good as the car was running 4-5 months ago perfectly with the stock coils. My only concern is 1) Is it possible to run stock coils with an EMS such as a microtech 2) What hp are the stock coils good for.The car is an S13 HB '89. P.S What are RB25DET Rods good for (AT MOST)The car is pretty much full interior.What HP & TQ #'s do you see the car acomplishing. What 1/4 mile time considered the past post that one owner went 10. 6 with about ~~ 480 rwhp.How much can a J30 Diff, and an otherwise stock rear end handle in these cars.

Thanks for the help....
Modified by SillyRB at 9:45 PM 6/3/2005

[kouki-gymkhana]

Goddamn that sucker's pretty!

[gawdzilla]

looks nice. stock coils should be fine for a bit. might want to look into a split fire or something in the future. i'll prolly end up doing that.

how'd you get the block so greasy/shiny? wd40? paint? my block is the color of... rust haha and it is bone dry from the hot tank

[Imissmyturbo]

First of all thanks for the picture with the HKS manifold mounted to the motor. So that's a PT67 turbo? I though the the PT67 could only come in an S cover and with the HKS manifold the an S cover T4 compessor wouldn't clear......Anyways.

The car that went 10.6 was running more boost then when he dynoed it. He made 440 RWHP @ 14 psi. He was running 17 psi when he went 10.6 @ 130The PT67 turbo is the most powerfull turbo in a T3/T4 configuration. Making 550+ WHP isn't a problem with this turbo. They flow 75lbs/min (750 hp). Make sure you keep your A/F ratio safe. Does the microtech have any knock detection? As for the coils I am not sure of a limit they have. I have red about an RB26 using 2JZ coils. I am not sure how that works or what is needed to do that. If you can get a GM style waste spark coil pack. They use 3 coils for 6cly's. Then you will (IMO) a better more reliable/cheaper to replace coil setup. You will also free up 3 outputs from the ECU.

So how is the clearance with the steering shaft? Do you have any pics? Did you redrill the manifold?

***Edit*** I see that's a T4 hotside.

[SillyRB]

First of all thanks for the picture with the HKS manifold mounted to the motor. So that's a PT67 turbo? I though the the PT67 could only come in an S cover and with the HKS manifold the an S cover T4 compessor wouldn't clear......Anyways.

The car that went 10.6 was running more boost then when he dynoed it. He made 440 RWHP @ 14 psi. He was running 17 psi when he went 10.6 @ 130The PT67 turbo is the most powerfull turbo in a T3/T4 configuration. Making 550+ WHP isn't a problem with this turbo. They flow 75lbs/min (750 hp). Make sure you keep your A/F ratio safe. Does the microtech have any knock detection? As for the coils I am not sure of a limit they have. I have red about an RB26 using 2JZ coils. I am not sure how that works or what is needed to do that. If you can get a GM style waste spark coil pack. They use 3 coils for 6cly's. Then you will (IMO) a better more reliable/cheaper to replace coil setup. You will also free up 3 outputs from the ECU.

So how is the clearance with the steering shaft? Do you have any pics? Did you redrill the manifold?

***Edit*** I see that's a T4 hotside.

First of all i had to re-drill the manifold, tap it to a T4 flangeThe compressor is a S cover. I am using solid motor mounts that alow the turbo to clear, the compressor is slightly touching the exhaust manifold but that does not really matter since the temperature is about the same in the turbo as it is in teh exhaust manifold. The exhaust side of the motor is about a 2/5 of an inch higher than the intake side of the motor. The oil pick up i believe is on the intake side so there should not be much of a problem. I am using a -12 for the return so i know i have no return problems. The turbo is a straight T4, with a .81 back. I believe i am the first to use th HKS exhaust manifold in a US spec 240 with the RB motor. There was not to much work required. I thought about Bosch coils but money is getting tight.

Hopefully i can get 6xx out of the stock coils....I want the car to go 140 ...That is all i want...Is that too much to ask

[SillyRB]

The steering column has about 3/4 - 1 inch clearance from the V-band. Will have more pics in a week or 2.

The block was painted by a friend of mine who works @ a machine shop....NOT sure what he used....we were bored and he had some special Paint from Calico that is very heat resistant...so what the heck we tried it

[goofynick6]

I know microtech rocks, and you can tune fuel to each individual cylinder, so I'm guessing it should work fine with your coils. Looks like an awesome setup!

Nick

[SillyRB]

I know microtech rocks, and you can tune fuel to each individual cylinder, so I'm guessing it should work fine with your coils. Looks like an awesome setup!

Nick

Thanks man....Hopefully the car should be running in the next week or 2....There is a SUPRA meet in Orlando on the 24 of June....Am trying to get it done / tuned etc Before then. Time is of the essence. My only concern is the stock coils with an EMS such as a microtech.

[fly240]

very nice sallyrb, keep up the good work...

[StricNyne]

wow, very nice setup heheh

[SillyRB]

Thanks alot fellasAll advice is welcome.....Please help a brother out....More incite on the Coil Packs and Rear End.....AT MOST...what do ya'll think stock rods are good for ?

[Imissmyturbo]

Not sure about what the stock rods are good for. I would guess 550whp maybe more if your tuning is really good and your not reving above 7800 rpms. I think the ringlands on the pistons are what will be your limiting factor.

As for J30 rear end power won't kill it if you are doing hwy pulls. It's high RPM launches on slicks that is hard on them.

[lyon23]

Thanks man....Hopefully the car should be running in the next week or 2....There is a SUPRA meet in Orlando on the 24 of June....Am trying to get it done / tuned etc Before then. Time is of the essence. My only concern is the stock coils with an EMS such as a microtech.

Are you in orlando right now? give Rolo a call at Central Florida Turbo he was the one that tuned fitos car with the lt-12.. he knows those things like the back of his hand.. he can also answer your questions about the coils.

ps the set up looks real good.

[Yellow4g63]

I believe i am the first to use th HKS exhaust manifold in a US spec 240 with the RB motor.

maybe the 1st with a RB25, CarlH has one on his RB20 with a GT30R turbo. He said the same thing about the rack. Maybe one day he will post the pics for everyone to see lol

[SillyRB]

Are you in orlando right now? give Rolo a call at Central Florida Turbo he was the one that tuned fitos car with the lt-12.. he knows those things like the back of his hand.. he can also answer your questions about the coils.

ps the set up looks real good.

Yeah Rolo is the one who is going to be tuning the car. Rolo is not to sure about the stock coils as well as he has only tuned 1-2 RB25's.I have spoken to Mack @ Mckinney as well he stated that stock coils and rods are 'iffy' over anything over 500 rwhp. Well then again this all depends on the way the car is tuned. XS Engineering & HKS sell an 'ignition Booster" i need to get more info. but that is what Mack had told me. As for the rods, i am confused because i have seen several RB25DET's with aftermarket pistons and stock Rods, all new bearings of course putting out 650-700 rwhp. To my knowledge RPM is the killer of rods, the car won't be going over 7800 ish RPM.

[biglipzit]

wow i am indeed impressed! Great jobe and clean sexy motor. The greddy intake with the HKS aexhaust really brings out the beauty of that engine. RPM truly is the killer of rods so if you are looking for above 500whp then forged pistons might be in your future. That turbo looks really sweet on that engine but i would be worried about the contact point where the compressor housing touches the exhaust manifold. Maybe it might be worth jamming a small piece of heat resistant or fiber glass cloth between the 2 to minimise heat transfer. Never heard of solid motor mounts being used. With above 500whp i would be scared of damaging my chassis with no dampening from engine torque at WOT pulls. Those engines normally pull to the side don't they? Goodluck with the project and more pics! Are you using the stock flywheel also?

[Slo_240sx]

Beautiful work there. I would say anything over 500Hp the coils could be replaced. Like the guys said split fires or even the expensive bosche ones will work.

I would be very concerned about your unibody. This is where you shouldn't be putting a budget on. Get a nice roll cage setup to tie the body up. With that much horse your chassis is going to tweak on hard lauches and then your car is junk. A nice roll cage will stiffen it up and help alot. As for the j30 lsd It should hold up just fine I would be more concerned about axles. LS auto makes upgraded ones made of chromoly. The guy that ran 10.60's had a R33 diff and blew an axle out. Axles should be more of a main concern that the diff. -Alex

[SillyRB]

Beautiful work there. I would say anything over 500Hp the coils could be replaced. Like the guys said split fires or even the expensive bosche ones will work.

I would be very concerned about your unibody. This is where you shouldn't be putting a budget on. Get a nice roll cage setup to tie the body up. With that much horse your chassis is going to tweak on hard lauches and then your car is junk. A nice roll cage will stiffen it up and help alot. As for the j30 lsd It should hold up just fine I would be more concerned about axles. LS auto makes upgraded ones made of chromoly. The guy that ran 10.60's had a R33 diff and blew an axle out. Axles should be more of a main concern that the diff. -Alex

Thanks alot. I dont plan on Launching it until i get atleast a cage...That will be another month or 2 need to save some more lunch money. If i take it to the track when its done i will just roll it out in first then PUNCH it in second and see what kind of mph it can get. When the car is said and DONE i want a 140 trap speed. I will look into those axels.

thanks everyone for your help

[Imissmyturbo]

I think you will be fine with the stock R33 axles. The guy who ran 10.6 blew out his stock rear axles that were ran by the stock diff that he welded. The r33 axles are a bit larger then the s13's

Do you know how much whp it will take to trap 140?

[SillyRB]

I think you will be fine with the stock R33 axles. The guy who ran 10.6 blew out his stock rear axles that were ran by the stock diff that he welded. The r33 axles are a bit larger then the s13's

Do you know how much whp it will take to trap 140?

Well in all honestly i dont knowI figure in the same chassis with 320 RWHP my car went 119 Considering i had a SR20 @ the time....So in all honestly i have no idea, It depends on the weight of the car as well as the amount of power it makes. My estimate is somethign around the 2500 lbs range (With driver) and abuot 620 ~ RWHP should get you into the 139-141 mph range . Well then again the guy on this board went 10.6 @ 130 with approx 480 rwhp. So you might need a little less that 620rhp .... Like we said it just varies on Power and Weight.

As i have read the J30 axels are approx. the same size as the R33 axels ?

[Imissmyturbo]

Ya I think they are the same. They have the same pattern atleast. How did you get your car down to 2500 lbs? I think my car is around 2900-3000. I would love to get it down to 2500!

[SillyRB]

Ya I think they are the same. They have the same pattern atleast. How did you get your car down to 2500 lbs? I think my car is around 2900-3000. I would love to get it down to 2500!

IN all honesty 2500 lbs is an estimate...I will weight it again when the car is running again. Should be soon. Well the car has no AC / PS Compressor, Bumper Supports are missing as well as other various things that were not being used. There are a bunch of other things that have been removed. WIll let you know, once i know how much it weight. But i know for a FACT an average RB swapped S13 is around 26-27xx lbs.Give or take a few. Do NOT be fooled by curb weight.