Jump to content
HybridZ

How much HP is enough?


Guest Anonymous

Recommended Posts

Guest Anonymous

(No, I still can't decide what to build)

 

I origionally planned to simply rebuild the 300 horse 350 I have and putting in a good camshaft, but people keep recommending stroker kits and performance heads and blowers and all sorts of off the wall stuff.

 

So how much is too much?

I'm on a budget, and I'm not going to be doing any real dragging. Just gonna be cruising around the beach. All I want is a street machine that has good power all through the rpm range and that will leave 'most' vehicles behind.

 

I figured that 350 horses from the engine I have with a good cam and a few cheapy changes would be enough, but I don't know. What is the deal with stokers and what not?

 

Thanks in advance

Jack

Link to comment
Share on other sites

I don't think enough is ever attainable!!!

300 or so HP will be plenty, but I guarantee that once you are used to it, it won't be nearly enough.....chasing the HP demon is a multi-Billion dollar industry for a reason icon_biggrin.gif

Tim

Link to comment
Share on other sites

Well, I just had my car dyno'ed at "only" 300RWHP. I can tell you that it's pretty darned fast - figure it's 350HP at the flywheel. I don't think you'll have much trouble beating folks with that much power and if you decide you want more swap some parts and get more. You don't have to have a zillion ponies but you can always upgrade. Heck, build for 300 if you want and hit it with NOS for more HP later down the road.

 

At some point I think you can have "too much". One of us is hitting 9s in the quarter which is really impressive but breaking rear diffs left and right must sure get old. Personally I'd be happier going a little slower without breaking things - obviously not everyone feels that way though (shrug). It's up to each individual to figure out what's good enough - realize that over time you'll probably want more icon_biggrin.gif This isn't a project you'll build and never turn a wrench on again I'm pretty sure!

 

I'm only trying to get more power out of mine because it "should" be making something like 100HP more and I'd like to post a bigger number than a particular person. Sort of a pride thing. Besides, if you pay for X amount of HP, buld for it, and then don't have it you kind of get a little annoyed icon_smile.gif

 

I think you'd be plenty happy with 300 or 350HP. Sit down and do the math as to what that power will get you with about a 2500lb car. I think you'll be pleasantly surprised! In a daily commute or cruise you will most likely be coming up against mid 12second cars or slower with some exceptions (obviously). You'll be right there with them or better if you can drive...

 

Hey Andrew - would it be possible for folks to post their guesses as to what their HP and weight is along with their times? Might make conversations like this much easier. Jack, have you looked at Andrews page of timeslips yet? Maybe pick a range and ask those folks what they run?

Link to comment
Share on other sites

Guest Anonymous

Fast is fast, until you meet up with something faster. You WILL want more. I started with 250 hp, not enough, 350 hp, not enough. 475 hp, just dandy. Low 11 sec times, cheap to build, cheap to keep and reliable. Simple 350 platform. Flat tops and 55 cc heads. Big valves and open plenum intake. Hydraulic 234 degree at .050 cam. on 110 degree lobe center. Hooker 2147 headers. (Full length) 11.3-1 comp, 91 octane. Have seen several 20 mpg road trips. The car truly scares me at times. The throttle response is incredible. This level of output has not hurt the drivetrain ever. Over 600 wrinklewall burnouts, four years of constant bracket racing, hill climbing, street racing, and grocery getting since 1996.

We built a money no object 386 inch stroker. No mileage, and it hurts rearends if hooked up. The 475 hp car actually runs better on the street because it gets traction sooner. Neither car has tires wider than 10 inches. The cost between the two engines was substantial. Almost twice as much. Return on investment and best bang for the buck, stay in the 350 platform and shoot for under 500 hp. Just my .02 worth.

Kim

Link to comment
Share on other sites

Guest Anonymous

u have trouble hooking up a 500 horse at the motor car?

 

my car makes 700 rhwp and hooks good with a 235/60/14 m and H street legal tire..

Link to comment
Share on other sites

Guest Anonymous

All things being equal, (if you and I have identical cars with exactly the same gears in the trans and rear end) then the only other possibility is that perhaps I have underrated my engine. My bracket race computer factors usable HP by comparing MPH against GVW. This computer comparison indicates only a touch over 400 usable HP.

This car was allowed to make only one sub-11 second run before NHRA rules sent me packing. This was a 10.9+ pass at 129+ MPH.

This run was made on a sea level equivalent air day at a 2700 ft track. The car has posted numerous 11 teen's to thirty's times on 91 octane pump fuel.

I would be curious what ET's your 700 HP car has generated. If our HP figures are anywhere near correct, you should be in the low tens or high nines.

A friend of mine has a 1972 3.8 Buick turbo car which dyno'd at over 600 hp and Torque, yet on an average it is only 2/10ths quicker in the quarter than my desk top dyno rated 492 hp motor. We both run lockup convertered 700 R-4s with 3.54 final drives. Both cars are 240's (1971 and 1972). Both have run at the same track at the same altitudes.

My point is that HP ratings just don't seem to equate directly to predictable ET's/ MPH or traction for that matter.

I recently read about a turbo Toyota which dyno'd at some incredible 770 hp! I read the entire article only to find buried down on the last page that the best ET the car had achieved was a mid 12 sec pass. I was disappointed both from the lack of performance, but also the cost of this rolling test bed of computer technology. One could build several Z's for the price!

Part of my traction problem is that my street tires are Z rated 245-50-15 BFG R1 radials. I like sustained high speed driving on mountain roads and have competed in many SCCA hill climb events in the Northwestern USA.

My bracket racing tires are 26x10x15 DO-5 Hoosiers, which hook well if properly heated before each pass. The car posts consistent 1.600 (+) or (-) a hundredth, 60 ft. times.

M&H's as well as the BFG Drag radials I have tried are not speed rated by the manufacturers but did hook the car up better in a straight line than the R1's. This lack of speed rating dictated for me that prudent driving would be limited to short bursts high speed driving which is not where my car is driven on "occasion." Soft sidewall tires are not known for their tolerance of the heat generated by sustained high speed driving. I have bought all to many Z cars which were rolled up into crushed metal egg shells to believe that it can't happen to me.

As I said in my earlier post, both cars are equipped with 10 inch wide tires, but not 10 inch street drag tires. It simply isn't a good comparison of HP considering the traction differences between M&H's and R1's.

It is tough to have your cake and eat it too when it comes to raw traction versus cornering ability. I wish someone would make a DOT high speed casing gumball compound radial tire in a 275-45-15 for say $100.00 each! Till then traction for me will be a compromised by the need for sustained high speed driving which this car is subject to.

One trip this summer covered 1500 miles in three days across 100+ degree deserts and mountains of southern Oregon and northern California. (All Datsun Meet in Shasta Ca. in July)

Kim

Link to comment
Share on other sites

Hey 1fstz

 

where do you order/buy M&H tires? i burned a set almost to threads i liked then so much but cant find where to buy another set... they were 275 50 15 racemasters. they were really soft and hooked really good. I aquired them when i bought my wheels ;>

thanks

clint

OBTW your crazy!!!!! 9 seconds with no cage !!!!! one of these days you wont be able to open your door after a run ;> can you say pretzel :>

Link to comment
Share on other sites

Guest super280z

hey idaho, have you ever heard of Nitto dr's? they make an awesome z-rated radial that will hook great on the street and still handle awesome topend. look for the 555 series. only about 125 bucks for 275/40/17's

Link to comment
Share on other sites

Heh, I started to mention the DRs too but I couldn't recall what the speed rating is. I've found they drive just like regular radials but seem to be much stickier. I can hear them chucking rocks up into the wheelwells whenever I hit any gravel - stuff just sticks to them icon_smile.gif Would mean running 17s though and it sounds like he's got 15s. Unfortuntly they don't seem to make them in a smaller wheel size. They also make a 24545 which will fit in the stock Z wheelwell with careful offset seleciton.

Link to comment
Share on other sites

  • 2 weeks later...
Guest Anonymous

hey, 1fstz, what's your rear suspension like? I'm 'only' going to have about 450hp but I can't imagine my car will stick without some big tires. Just curious if your suspension has anything to do with it...

Link to comment
Share on other sites

Guest Anonymous

i run h and H race master tires.. 235/60/14

 

stock springs with a ruber stoper in them to stop TO much sqat but to still allow fast initial squat ...

 

other then that its totaly stock with a 88 300 zx limited slip center section..

Link to comment
Share on other sites

Guest Anonymous

Stock? Hmm... Well, I was planning on leaving everything brakes/suspension/rear end stock until I had all the parts to do everything at once, so... I guess I'll be seeing how well the pizza cutters that came with the car hold up. icon_smile.gif Once I burn them up I'm gonna upgrade the wheels along with everything else.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...