lilesrebel

Ive read over this thread alittle bit. And i too have a (close to stock) 1978 280z (black pearl edition) was a 4 speed car, now a 5 speed. before i had just took off the huge bumpers and just had nothin but the big open mouth in the front. i ran my car 4th gear pinned speedo bouncing between 135mph and 140mph. it felt like it was floating pretty good. lol. kinda shakey. i put the msa type 2 air dam on it and i havent tried those speeds in awhile. but 90mph is a breeze. rides smooth as ever. but i do gotta say that i dont have fuel injection. i converted to the bob sharp 4 barrel intake with a 390cfm holley. maybe this adds alittle power to help me get to those higher speeds. lol. not sure.

I dont know if You have or not but if you have seen the exhaust manifold on a 260z it's completely different than a 240z or a 280z manifold. the 240z dosent have the strict emmissions on the car as the 260z had. the shape of the 240z manifold compared to the 260z is similar though. the 280z had a longer bigger and heavier manifold than the 260 and it flowed better to the hp on a stock 240 comparred to a 260z the 240z is higher. when the government issued strict emmision control laws in 1974 nissan didnt know how to deal with the problem so they upped the liter size and put the emmissions on a twin su carburated setup resulting in lower horsepower than the 240z which is why the 280z with bosch L-Jetronic fuel injection was born, so the it could have the emmissions control but still good power 240z hp: 151 260z hp: 139 1975, 76 280z hp: 149 1977, 78 280z hp: 170 to my knowledge this is right but im sure someone on here knows more about it than i do

oh and hey stevechode do u still got the stock head from your car because i might be interrested in buying it from you i dont live to far away im in locust NC 20min from charolotte just contact my back in this thread if u still got it. thanks

i am running a full 2.5 inch exhaust from a 6 into 1 header from AZC to a flowmaster for starters. i might change the muffler later if i get tired of the flowmaster. but i would think that i would gain 15-30hp considering the stock exhaust is so restrictive, and the manifold has the crappy emmission control setup the car will be painted this month and the motor will be put back in shortly after then i will run my exhaust. the car has been put through a rough ground up restoration and it is all comming together again. I will post some pictures up in this thread as soon as i can. thanks for all the help.

so you think that 3 inch would be to big for a NA L28 Im no longer going to turbo the motor. I probally will use the 2.5 for low end torque but if 3 inch isnt to big and i cant still have good torque then i will use that. but for now im leaning toward 2.5 because i can get piping and every thing else i need cheaper than 3 inch.

since it is 2009 I don't have to get my car inspected at all because it is 35 years old and yes it is in NC. I'm not 100% sure on a cherry bomb yet or any other muffler but i have decided that i would put a flange at the rear so i can use different mufflers just as long as it has the same type of inlet and outlet. and also i'm going to run a electric cut out right after the header. so i can have just a straight header with the flip of a switch. and i also have decided that i wont turbo the car unless i do get a RB26DETT later on i would have to change my exhaust completely then, because of being turbo charged and needing a larger diameter exhaust than a N/A. I will probably run 2.5 inch exhaust on the l28 to keep low end torque. The flowmaster 40 series sounds great on these cars IMO as expressed in this video but the dynomax sounds great to and i will have a cam very similar to his. but then again the N1 muffler sounds great to but it does look ricey from the back The flowmaster super 44 will more than likely be the muffler i choose to begin with because i can get it for cheap. but i might change it out later. for something else or swap the motor.

No why? do u have any better suggestions? im always open to any input.

I may not even get the twin idler gear now considering I'm running tight on money because of Christmas and i want to finish the car before spring time, so maybe i will buy it later or say the hell with it, because the stock one still looked fine with over 220,000 miles on the motor. so maybe i will spend the money on something else like suspension or rear disc brakes. really the only reason why i did like the twin idler gear is because it reduces friction on your motor, so i thought it would make it revup quicker. I do plan on running it on a road course, but not extensively. just to see what it will do. thank you for your advice.

I allready have forged pistons, and headwork done to the engine. the motor still needs to be put together so i figured i would get a twin idler gear because it would be easier to put it on, and plus i dont like the stock timing chain tensioners design. and You said if i dont plan to spin higher than stock redline it would be a waste. Really all im trying to do is build a reliable car with good horsepower. i may not even turbo the L28. I might put a RB26DETT in it years later. and the 600cfm holley should still be good at high rpm considering most scca datsuns run a 390cfm carb. so i should still make good power. im also looking into MSD ignition. but im not an expert on this. I think i narrowed it between these mufflers any input? http://store.summitracing.com/partdetail.asp?autofilter=1&part=FLO%2D15430&N=700+4294923429+4294922710+400238+4294891681+4294791977+316877+115&autoview=sku or http://store.summitracing.com/partdetail.asp?autofilter=1&part=BOR%2D40085&N=700+4294923429+4294922710+400310+4294791977+115&autoview=sku or http://store.summitracing.com/partdetail.asp?autofilter=1&part=MPE%2D14806&N=700+4294923429+4294922710+400636+4294891681+4294791977+4294906132+4294906130+4294906131+4294906122+115&autoview=sku Dynomax is also a good muffler but then it would sound just lke my 1994 Toyata pickup with a 22re its running no cat with 2.5" pipe to the dynomax which exits before the rear tire. thanks for your help.

If you are looking to make some big power. throw away the su carbs! go to www.thezstore.com for several performance options. but as far as a simpile performance change I would go with a 4 barrel intake conversion and header from www.arizonazcar.com you should be able to push a little over 200hp with that or you could go with a tripple webers setup but I would suggest the 4 barrel conversion, because that is what im running on my 260z but mine is from bob sharp racing but the design is the same between them. your stock pistons should be fine depending on the miles of the car. my 260z had over 300,000 miles on them and still looked good. a cam is a good gain but it can get a little costly just check out www.thezstore.com for tons of performance stuff. and I dont think there is a big power difference between the late and early 260z but i wouldnt know for a fact. my 260z was made in december 1974. but i threw out the su carbs years ago. Exhaust. probally a 2.5" exhaust out to a muffler of your choice would be best. but im not an expert on exhaust. good luck!

wow after skimming over this thread and veiwing this car you got the deal of a life time! my 260z was made in december of 74 it has about 220000 miles on it. and it shows it i guess thats why im doing a ground up restoration! costing me about $8000!! you are very luky. nice car

Ive got a 1974 260z, im using the 260 head on a bored out 280z block. im using a 4 barrel intake conversion from bob sharp racing with a 600cfm holley carb. i want to put a turbo, or a centrifical super charger on it but Im not sure if it can handle it? with it being carburated. Ive seen it done on v8's but i cant find any thing on the L28 being carburated with forced induction. THANKS lilesrebel

Im currently building a 1974 260z with a L28, 4 barrel 600cfm holley, header, twin idler gear, mild cam, and other basic stuff. But the motor is not in the car yet because i still need to paint the car. I might put a turbo on later, so im planning on using at least 3" exhaust but i cant decide what kind of muffler. Ive looked at flowmaster, magnaflow, borla, and apexi but still dont know what i should go with. i dont want it to sound ricey but real deep, similar to a v8. big phil's turbo 280z on youtube is the best sounding z I've ever heard but he is running 4" with a deisel muffler (which is way to big for a NA motor like mine) here is his video: Can anyone give me some good advice. and what is the best header? 6 into 1 or stahl? any advice would be much appreciated.