loosenut

ok, im sure people have talked abou tthis before,lol. i did a seach for "P79" heads off of an 81zxt and NOTHING came up,on here. i was just curious i have a 79 N/A zx 5 speed. and of course i wanted to turbo it, some one said that my block was better due to dished pistons, but the head was junk, and told me P79's were better. if this is true would that be the combo i want? why wouldnt the turbo block be better,or is it? if i dont go this route i will be purchasing either an RB25DET w/all wiring, ecu, chip codes and 5 speed trans, or i will purchase the RB26DETT w/all the same stuff. help me eliminate my options. i would like to focus on one direction. im leaning towards the RB26DETT, but i need more info to make a solid decision between the three options, L28ET,RB25DET, or RB26DETT. please help,lol mind is spinning need to pick a route and stick to it. thank you very much for time and help.

jfairladyz

The turbo block IS better. Its a stronger block with better coolant circulation around the cylinders and it also has dished pistons. The 81+ blocks are the same as the turbo blocks but come with flat top pistons so the compression is higher which is probably why you were discouraged from using that block. But the block itself is still better than earlier blocks. The F54 block is what you want. The only benefit of the P79 over what came in the previous Z's is the bigger valves. The P90 would be best though cause it doesn't have the exhaust liners in the exhaust ports. Thats the only benefit the P90 (turbo head) has over the P79. As far as RB's go: what are your power goals? If its a reasonable number and "flash" doesn't matter to you then the RB25 would be a better choice since it comes with a trans you can use and is going to be on average $2000 less than the RB26 (which you'd still have to shop out a trans for so add even more to that difference). If you're looking to make all out power, want the bragging rights of an RB26 and money is no issue (within reason) then the RB26 is your motor. The single turbo of hte RB25 is also an easier fit due to the fact that the turbos of either motor are on the same side as the steering column and thats the biggest hinderance with those swaps. If you've got the money and time then I'd go with the RB. But if you just want a solid motor for street performance then the L28ET is a great motor to go with. I'd take the RB (considering money wouldn't be affecting my decision) simply for the fact that I could say I've got an RB in my Z If you do go L28 do yourself a favor and toss the heap of iron you've got in your 79 and get the turbo motor. You'll be greatful you did And before you even consider forking over the money for an engine, upgrade to an R200 diff out back. You've got a 79 so you most likely have an R180 which is going to be your wink link when you start putting out big power.

NismoPick

yeah... what he ^ said!

Lost Vegaz

Don't forget the sr20DET. Cheaper than the rb's, really good power, parts availability, and since they are 4 cylinder and shorter, you can virtually mount em anywhere. Been proven to be extremly durable and very powerful. That's my next plan.

260DET

If my US sourced two seater ever comes through, it will have a Nissan V6, preferably a VG33 with turbo.

This RB25/26 and SR20 fad in the US has me beat, lots of better V engine choices and the Supra turbo straight six which is stronger than the RB. Plus the Toyota's exhaust is on the RH side, ideal for you LH drivers.

jfairladyz

Its the whole wanting what we cant have. We cant have an RB powered car here in the states. So we instinctively feel the need to put it in our cars. The Z is the perfect platform for the RB since we dont have Skyline.

Of course for vehicle dynamics a V engine would be far superior to the inline motor. I'd take a VQ over a VG though since it's aluminum. Might as well keep weight as much to a minimum as possible.

Lost Vegaz

sr20's are light and in my opinion a great engine for a Z. You don't need alot of power when the car itself is light. And still a 2 liter that makes over 2 hd hp. Perfect for the street.

loosenut

i thought about the VG30DETT as well but ive heard that if i wanted that to go for the LS1 because its lighter?? but this is all good info i def want the flash part about the RB's as far as price goes, ive found complete swaps for both the RB25& 26 all come with ecu,wiring and 5speed RWD trans(the other RB26 i found had the AWD trans in it,blah) the 25 was 2200. and the 26 as 4300k so that being said its down to a money issue, if i got it ill go for the 26 if i dont then 25 is my baby. any other info on what to look out for is welcomed as well

jfairladyz

Definitely head over to www.hybridz.org for info on the RB swap. While I dont think anyone on there has done it into a ZX (but I have seen it done in pics) the basics are the same. They can tell you what to look for when you buy the engine and what accessories and stuff you'll need to grab. As far as getting the engine to bolt into the engine compartment I've heard it's pretty straight forward if engine placement isn't a big deal. But theres still fabbing to be done. I know the if you go RB26 then you need an RB25 oil pan cause the 26 pan has the axles running through the pan. The RB25 pan still has to be modified though. I'm really debating whether to go LS1 or RB myself. I know as far as driveability and power production goes the LS1 would be best. It's also lighter than the RB's or the VG. The engine itself is really light. It's the tranny that adds all the weight to the swap, but that weight is in the middle of the car so it's not as big of a deal. The RB26 trans can be used if it comes with the engine you buy but the transfer case must be disabled and sealed up. The LS1 swap is also cheaper and easier. But a lot of people have a thing against the chevy motor in a Nissan and since the car I'm doing is going to be meant as a promotion vehicle for my company I've got to think of more than just what I want. If I do go with the RB then I plan to market the all the parts I fabricate for the swap. What ever route I go I'll be starting this spring. I just want something thats going to draw a lot of attention to the company. I think an RB26 will do a good job of doing that.

The more parts you guys buy the sooner I can get the swap done Basically this years tax return should fund the start of the swap (and the wife has agreed to donate a good deal of hers to the project since it's a company car ). Who knows, you guys might be seeing an AWD ZX in the months to come Now that would draw a lot of attention

SHADY280

I Got A P79 Built Motor. Ask If You Got Any Q's About It, I Had To Do Mega Research For The Machine Shop For Mine. I Know Just About Every Mod. Just Dont Take Out The Liners