[tdignj]

I'm installing an L28 engine in my '71 240z and want to know what I could do to get more power.

The block is a F54 and the head is a e31 that has been reworked and has a decent cam in it. I'm not sure of the details of the cam. The block has been bored .050. I'm not sure of any more details of the engine since I bought it from someone. I'm going to assume that my compression is somewhere in the 10.5 to 11 - 1, but don't know for sure. I will be using SUs with SM needles and gross jets. The ignition is MSD.

I was thinking of using Nitrous but don't know if i want to. Does anyone have any other ideas of what to do for more power?

Tom

 

[yo2001]

triple carb. NOS sounds good but not real good for high compression engine

 

[tdignj]

I don't want to do triple carbs....It's hard to find someone who can tune them. Plus, dual SUs will work fine. What about superchargers?

 

[yo2001]

Jim wolf has a supercharger kit

 

[Zuber]

You didn't mention it, but did you do anything with the stock valves that came with that E31? I believe you can swap the intake valves for larger N47 valves (280Z). Also, you can try to port and polish the head for better airflow.

With a high CR, I don't recommend turbos or nitrous oxide. Dentonation at high compression ratios is an explosive event. Not to mention that you may get detonation just by running a lower octane gas. Timing off? Uhoh. You could opt to make that motor a stroker motor though. That would do wonders for your low end torque.

If you can build it any way you want to, why not do all the above, opt for FI, and use an aftermarket computer and ignition. Then you can dial in all the changes you want, and have rock solid performance.

My opinion.

 

[Stingray280zx]

I'm with Zuber here. You can't supercharge or turbo charge a Z with that high of compression. If you choose to stay with Carb all I can say is go with stroker setup. Honestly I think that high of a compression ratio will be alot of power, but put in the wrong gas and watch your engine get obliterated. I hope you are going to use this car for budget racing, daily driving with this car would be beyond retarded. Personally if you wanted some insane power for the daily driver, I reccomend a turbo setup, so than means switch to EFI. If you ask the question about the turbo being done on a carb engine, it can't be done. The carb does not give enough gas (I think) during boost. The POS Mustang had a 2 bbl turbo setup, where do you see those besides the junkyard?

-Emir

 

[Shreegs]

MEE TOO

I'm feeling you bro. I have a similar set up, and am unhappy with the low end power. Unlike you though, I'm going to put on a set of triple webers, if you can sinc. two carbs, why can't you sinc. three? I'm rebuilding the DCOE's as we speak, I'll post my results when they go on. Tim