Whats better a port polish job or a RB26 head for my RB25???

[Sky240PWR]

I was thinking of doing a port and polish job on my RB25. I know that will give me around 40-50 whp but i was wondering what if i just put a RB26 head on, has anyone done that before and how much hp did you get from it. Here's a dumb question, i have the GReddy intake right now, if i did do the RB26 head swap i would also have to switch the intake right??

[accel junky]

Rb25 and Rb26 heads flow the same. Just upgrade the valvetrain in the RB25 to the solid lifter type and you'll be golden.

http://www.skylinesaustralia.com

http://www.skylinesdownunder.com

[Sky240PWR]

have you or anyone you know on this forum done the valvetrain upgrade???

[Joe]

you cant just swap heads with a rb26 on a rb25, they arent the same.

it would be cheaper to just put a rb26 in.

[Sky240PWR]

Yeh right!!!!!!....I just paid 10 grand for my RB25 installed! They wanted 3 more grand for the RB26, i doubt it would be cheaper!! the only reason i am asking was because i read somewhere on this forum that you could put a RB26 head on a RB26 block.

[Joe]

Yeh right!!!!!!....I just paid 10 grand for my RB25 installed! They wanted 3 more grand for the RB26, i doubt it would be cheaper!! the only reason i am asking was because i read somewhere on this forum that you could put a RB26 head on a RB26 block.

you paid 10,000$ for a rb25 swap? jesus christ! thats a lot of money dude, did you research at all before you dropped 10g's?

and a rb26 head doesnt bolt to a rb25 block without heavy modification.

[Sky240PWR]

I had Mckinney do the swap, it included a GReddy intake and intercooler with piping,Touge downpipe,LSD,new timing belt,gaskets and seals, gauges, electric fan,ect.....and as far as the rb26 head, if it doesn't bolt on then forget all that nonsense, i'll just swap some of the internals and port the head.

[Nameless EJ6]

As far as I know, the RB26 head does flow better at higher rpms.

However, I don't see any reason to do a port and polish or swap heads unless you're over 450 hp..

Upgrade the turbo first.

[JonPowell]

Just polish the exhaust side & get a bigger turbo. The turbo will overcome any imbalance/imperfections in the intake side.

Save the money if you just spent $10K

[Sil240]

40-50 Wheel HP??How much power do you have now????You must be putting up big numbers to gain 40-50 WHP from a port and polish job

About the valve train swap, can the RB26 Solid lifter setup be put into a RB20 HeadI know the retainers and the valve springs are different from the RB26 because they are VG30 stuff

[Sky240PWR]

well it was a package deal, they port the head, intake, beefer cam and bigger throttle. I'm at 250 whp now.

[Sil240]

oh yeah cams will do that with the port/polish jobWhat kinda throttle? Q45 90mm?Are you doing springs, retainers, valves, anything else?

[Sky240PWR]

yeah i'm using the Q45 throttle, not sure about the 90mm, well i had the port and package done to my RB but somthing went wrong with the head(low compresion in cylinder 1 and 2) so we stuck a stock head on there for now till i can find out what went wrong.GudePerformance(bullfrog) did the port and polish.

[turtl631]

Holy crap, $10,000 for 250 whp??!??! You got ripped off buddy...

[mkory]

I know it doesn't come with all the cool stuff yours did, but the place that's doing my rb25 swap charges only $4200. Lucky me I guess.

[Sky240PWR]

what motor mounts are you going with? and is that the price of the motor and swap or just the swap?..mine was 10 grand for everything (motor and swap) cause i thought the RB25det qwas going for around $3000-3500 and that means you're only paying like 700-1200 for them putting the motor in!!

[mkory]

True. I'm not sure what mounts will be used, but I shot the place an email to make sure that the $4200 included the motor, and got back this:

The $4200 price covers motor, transmission, mounts, and install. The only thing that would need to be finished before it can be driven away is a downpipe and exhaust.

[Master_Tao]

True. I'm not sure what mounts will be used, but I shot the place an email to make sure that the $4200 included the motor, and got back this:

The $4200 price covers motor, transmission, mounts, and install. The only thing that would need to be finished before it can be driven away is a downpipe and exhaust.

what shop are you using? I'm right over in ohio and think that would be an awesome price.

[mkory]

http://www.modernspeedlabs.com

[s13rb25det]

yeah my swap is just under 10k! that is including the 2k 240sx though! and I did all the work my self! I got a pretty good deal on my motor it was a r33 rb25det with 29k miles on it, it came with a bunch of upgrades to like an Apexi pfc, nismo 550 injectors, z32 maf,3 in down pipe, big fmic,intake,and a nismo short shifter! the total cost was $3200 shipped! the bummer thing abiut this motor though, was it came out of a cefiro!! so it has a little less power than a skyline r33 and I hade to get us r33 skyline motor mounts to work with the mckinney mounts.! and mckinneys transmission mount didnt work at all! but the ka mount fits perfect to the transmission.! the transmission that is with this motor is designed for a sedan like a cefiro!! it isnt as responsive as a skyline transmission but it still hauls a** even with the good deal on the motor I was thinking this swap would cost less,! but I have learned a whole bunch about these motors and thats half the reason I did it!! its also pretty fun beating up on 90% of the other cars on the road!! future plans for my ride are going to be a upgraded turbo(probably a t3/t4) and some decent suspension stuff, after that Im leaving it alone!!

[mkory]

Welcome to nico man. Those are some good exclamation marks you got there, thanks for flaunting them in front of everybody.
Modified by mkory at 11:01 AM 3/28/2005

[Sky240PWR]

Have you had the car dynoed? I would like to see how much hp you're pushing!

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