280z: turbo stock motor or go RB?

[LeX]

I've been looking in the turbo forums at the parts list for making a L28e into an et. Seems like an extensive and expensive list of things that would need to be done. It almost seems more cost effective to get an RB and go for a newer motor. I see complete RB25det swaps bordering under 2000 shipped on ebay and rb20det swaps for a good chunk less.

 

the engine in my car is recently rebuilt but with all OEM components, except i think perhaps a metal head gasket, unsure right now i'll check with the guy that did it.

 

 

Already have a full 3" exhaust i would mate the downpipe to and i know a lot of folks around here that can help me with wiring. What seems like the smarter idea? It's a 78 btw but that's not too important unless we're comparing it to carbed Z's as its already FI

[johnc]

I see complete RB25det swaps bordering under 2000 shipped on ebay and rb20det swaps for a good chunk less.

 

That's not a complete "swap." That's an engine. The swap itself will cost thousands more then what you pay for the engine.

[Vintage]

Which makes the NA2T swap look a whole lot better, especially when you consider it's practically a bolt on deal. I picked up two whole S130 parts cars (81 NA 5-speed, 83 Turbo auto) for 400 bucks recently. The turbo car had '72k on it. Cant beat that.

[LeX]

That's not a complete "swap." That's an engine. The swap itself will cost thousands more then what you pay for the engine.

 

 

i am aware of that..... by complete swap i mean the engine and all associated components. I know there are additional parts that need to be fabricated or altered. I would take it to a shop... i've had shops tell me around 5000 if they supply the engine and that includes tuning and FMIC exhaust everything

[LeX]

Which makes the NA2T swap look a whole lot better, especially when you consider it's practically a bolt on deal. I picked up two whole S130 parts cars (81 NA 5-speed, 83 Turbo auto) for 400 bucks recently. The turbo car had '72k on it. Cant beat that.

 

well let me know where to find one around GA lol..

[LeX]

i talked to Scott who rebuilt the motor. It's all OEM including headgasket but its recently rebuilt. I wouldn't want to go inside and mess with anything else so if i did the L28e-t then i would just leave internals alone... would just be doing the basics with something like a garrett GT35

[Zmanco]

I'm no turbo expert (being NA myself), but if you're starting with a NA motor recently rebuilt, do you know what type of pistons were used? If they're dished then I suspect you could probably run mild boost, but if they're flat top, then I doubt you can run much if any.

 

Turbo experts - chime in.

[LeX]

I'm no turbo expert (being NA myself), but if you're starting with a NA motor recently rebuilt, do you know what type of pistons were used? If they're dished then I suspect you could probably run mild boost, but if they're flat top, then I doubt you can run much if any.

 

Turbo experts - chime in.

 

more than likely just flat top... I might just go the RB route

[Vintage]

If it has the same pistons as stock, '78s should be flats I beleive. Mine is a '75 with dished pistons, so I'm keeping my N42 head so my comp doesnt drop to a measly 7.x:1

 

If you turbocharged the motor in your '78, you should have no problems running stock boost on stock electronics, and no problem boosting atleast 12 with an intercooler.

 

Oh, and it took 3-4 months of waiting and inquiring about every possible turbo parts car to find the deal I did.

[pjo046]

i am aware of that..... by complete swap i mean the engine and all associated components. I know there are additional parts that need to be fabricated or altered. I would take it to a shop... i've had shops tell me around 5000 if they supply the engine and that includes tuning and FMIC exhaust everything

 

I guess their 5000 quote is just in the ballpark range, and the real price when they're done will probably be a bit more. Turbocharging the L28E is not expensive at all compared. You get a new turbo for 700-900$, an exhaust manifold for 100$ off ebay, megasquirt will cost you a few hundred dollars, and then you need bigger injectors. FMIC and exhaust you would need anyways. The advantage with turbocharging the L28E you have is that you can do it in a stepwise manner, upgrading as you go along.

 

The CR you have on your L28E is 8.29:1 acording to the Lengine calculator, and that is actually lower than the CR I am going to have. So I wouldn't worry about your CR being to high, just make sure to avoid detonation as the stock HG will probably blow.

[panachedk]

for the l28e to et swap, id sell you my stock manifold and turbo for 100. for the money you cant beat the l28et.

[LeX]

for the l28e to et swap, id sell you my stock manifold and turbo for 100. for the money you cant beat the l28et.

 

how much for just the manifold> I would be buying a larger turbo regardless

[BleachZee]

dished pistons were used up to 1980. Flat tops would be in the F54 non turbo blocks in 1981-83 only if it is a stock setup.

 

The cost varies greatly. I don't see many people doing a non turbo L28 to turbo upgrade (as in modifying the existing engine) but doing a complete motor swap is easy. In my case I had a 280ZX NA and bought a 280ZX turbo parts car for $500. It did take a while to find one and I'm in Washington where they are plentiful. Out in GA you're screwed.

 

I swapped the engine in, had about $100 in misc costs, and made about $400 in parts sales from the rest of the car. Its old technology though and only 180hp to start with. The RB already has a much better ECU and head.

 

If your goal is 200-250 whp then just do the L28et motor swap if you can find one close to you at all.

You may just never find one though and be forced to order an RB25det. Dont' bother with an RB20DET, IMO

In my case I was not going to be able to afford a shop, nor would I consider it so the L28et motor swap made more sense. I don't have a welder for any kind of fab work or $5000+ for the RB engine at that time.

[LeX]

dished pistons were used up to 1980. Flat tops would be in the F54 non turbo blocks in 1981-83 only if it is a stock setup.

 

The cost varies greatly. I don't see many people doing a non turbo L28 to turbo upgrade (as in modifying the existing engine) but doing a complete motor swap is easy. In my case I had a 280ZX NA and bought a 280ZX turbo parts car for $500. It did take a while to find one and I'm in Washington where they are plentiful. Out in GA you're screwed.

 

I swapped the engine in, had about $100 in misc costs, and made about $400 in parts sales from the rest of the car. Its old technology though and only 180hp to start with. The RB already has a much better ECU and head.

 

If your goal is 200-250 whp then just do the L28et motor swap if you can find one close to you at all.

You may just never find one though and be forced to order an RB25det. Dont' bother with an RB20DET, IMO

In my case I was not going to be able to afford a shop, nor would I consider it so the L28et motor swap made more sense. I don't have a welder for any kind of fab work or $5000+ for the RB engine at that time.

 

yeah you cant find parts 280zx turbos around here. My last car had an RB20det and the 25 is a better buy , but 20 is a perfectly decent motor, just not the aftermarket support. I love the rb25det neo

[panachedk]

id sell the manifold for 50+ shipping

[datman]

I used a NA motor with a 2mm steel headgasket to lower the CR to 8.35:1.....with flat top pistons and a FMIC you can easily run 1bar (14.7psi) boost and should be able to get 350HP. You may want to fit a turbo oil pump and block the relief valve.

[TravRMK]

As many have said, the stock pistons are dished on the NA motors untill 81 when the f54 blocks got the flat tops. There have been many people turbo the NA motors. I will be turboing my N42 block.

[Pyro]

For less than 400.00 you can turbo charge your current engine over a weekend.

 

Go to your local "You-Pull-It" junk yard and get the following stuff.

 

280zxt exhaust manifold: 25.00

280zxt turbo with wastegate and downpipe: 50.00

280zxt oil line to turbo and J-pipe: 15.00

280zxt oil pan and oil pump pick up tube: 25.00

 

new stuff or used off e-bay

Bell engineering FMU: 225.00 new, 100.00 used

 

Connect exhaust: 50.00

 

Other things to do:

1) silicone up the advance slots in the distributor and set timing to 20 degrees.

 

2) Set fuel pressure on the FMU to 55-60 psi at 7 psi of boost.

 

Will allow your stock 78 to run a mid 14 second 1/4 mile at 96 to 98 mph.

 

Add mega squirt, stock 280zxt injectors, P90 head, an intercooler, and turn the boost up to 15 psi and turn some mid 12's at 110 mph. All with the stock turbo, which BTW, makes a fun street turbo due to no lag.

 

upgarde the stock cam and add a t04e-50 trim and run some 11's.

 

However, you will need a better clutch. A SPEC stage 1 or 2, 240mm for a 2+2 Z will do fine (nipponpower.com)

[panachedk]

after looking, i have the stock turbo, manifold, injectors, the turbo to intake pipe... if you are interested in any of it, pm... ill let it go cheap

[Zmanco]

Add mega squirt, stock 280zxt injectors, P90 head, an intercooler, and turn the boost up to 15 psi and turn some mid 12's at 110 mph. All with the stock turbo, which BTW, makes a fun street turbo due to no lag.

I think the NA injectors will run out of capacity as soon as you add the turbo. I was seeing 85% duty cycles with 225 cc (stock NA is only 180) on my NA with cam at 5000 feet elevation at the last track day. I can't see the stock NA injectors keeping up with any kind of turbo without leaning out when it's most likely to cause damage.