subject says it all.. I am currently starting to build up a 383 stroker. I have selected a eagle rotating assembly (all forged). I have not made decisions on a cam or heads as of yet. I'm looking for any feedback at all for reaching near the 500hp mark na. I would like to keep the motor tpi but am willing to concede that this may not be possible that way. I have already got a twin 58mm throttle body and will likely go with a stealth ram or equivalent. Questions? Advice... Fire AWAY!!!

 

I would stray away from TPI as they arent as good as a carb for making power higher up in the powerband.

What pistons did you get from Eagle?

If they are a dish your going to want to find heads with a fairly small chamber to get the compression up.

Do you plan on running pump gas?

This will definately be a big concern when calculating the compression ratio you need.


BUDGET???

 

Not out of the question, but the TPI part is probably unrealistic.

AFR, Dart, Brodix, some type of mongo flow heads. Lots of cam. Very little street driving.

 

500ft/lbs isn't unrealistic for a TPI 383 with some careful parts selection. You will probably only make 350 HP though.

 

TPI is nice for making gobs of low end torque but no good for HP or higher RPMs.

 

this will be somewhat of a street driver... I have a nice 3.73 posi out of a 4th gen to go in with the motor swap too.
I will be getting the forged aluminum flat top pistons with the eagle kit and it will be a pump gas machine. Do you think even going with an aftermarket intake this will still be a hard mark to make?

 

If you use an aftermarket intake then you're not really TPI anymore.

 

500hp easily attatinable, easily drinking 92 octane, and VERY streetable.

It's all about combination making everything work together.

 

My old 383 that I blew up years ago (specs still on my web pages) was producing around 500 hp on pump gas. It was a low buck 383 with a factory cast crank, factory 400 rods and rod bolts and cast pistons. Solid flat tappet cam and an 850 DP carb. Heavily ported camel heads with big valves.

It was in my car when I bought it but wasn't very powerful at the time. The engine had a lot of miles on it and I was able to get about 200 passes with it before it finally let go. Quickest I got was into the high 11's here in Calgary.

 

If you should build a naturally aspirated 383 stroker to achieve 500 HP, I'd say it won't be anywhere CLOSE to being a streetable experience.

If you want to realistically make big HP/torque numbers and remain streetable, get yourself a supercharger or turbocharger for that stroker.

My

 

You won't get even close to 500hp with a TPI intake.
The runners are too long and too small for high rpm and high air flow.

A short runner manifold like the LT-1 or Mini Ram intake will get you a lot closer. Can be done. Going to need very good heads 260cfm +++ Aftermarket EFI, big headers etc etc.
Probabily a solid roller is best. Most hyd roller setups have a lot of trouble beyond about 6200rpm. So a EFI that depends on a knock sensor should be avoided. You'll need to max out the compression ratio for the fuel octane you'll use.

But forget the TPI. Nice pretty setup but won't make 500hp.

 

If I were going to go 383 I would go with a carb. For a cam i would probably go with comp cams 304-TLS6 tight lash solid cam.
As far as heads go I have seen great results with the Sportsman 2 fully ported heads. They have a 2.05 intake 30 degree seat. Which is 275 CFM at 600 lift. The exhaust is 1.6. If you go with a carb go with a 850 and have it reworked to 960cfm.

I have seen a budget 383 stroker make 495 horsepower. All that went into this motor as far as price wise was $3,000. With already having the block and doing all the work yourself.

 

500 hp out of a sbc is not really a daily driver. I've heard many a person being able make gobs of torque throughout the powerband with that kind of power level, but the amount of stress on valvetrain components is going to be very high with the higher lift cams. Not to mention you're gas mileage will be downright awful. If you are going to switch to carb, you'd probably be alot better off going with a blower, as there would be alot less guess work involved with what components to use and you would be guaranteed good street manors, with less stress on top end components (because you would be working with a milder cam) and bottom end stress would be about the same, if not less because you could spin at a lower rpm while making the same power.

If you want to stay "TPI", the miniram intake is your best bet. It's runners are shorter then that of just about any carb manifold, and is probably the most reliable and potent way to make power, although its expensive. Of course, a good set of heads will be in order, you can probably get away with stock heads if you think you could handle a full port job on your own, but you'd probably be better off with a set of dart II's or a similar head.

 

You dont need a massive cam with large lift to get good hp/tq. It's all about how well your heads work and how much usable power you can generate under the curve. Think I'm crazy, for a VERY generic example, play around with DDyno and only increase lift and you'll see what i'm saying. Just like going crazy with compression does'nt net you very much power. You HAVE to run more compression with larger duration cams to make up for pressure bleed off due to valves being held open longer, just by running 14.0:1 compression alone with any cam is'nt going to make it a power house...you HAVE TO MATCH the entire motor or esle your pizzing into the wind.

FWIW, I just went out and got 4 intake and 4 exhaust valve springs tested to see how they held up after 2 years of racing and street driving, keep in mind these are the GARBAGE K-Motion springs that are notorious for losing poundage over time, I went from 220lbs @ 1.250 new to 215-217lbs @ 1.250....and this thing was raced and going numerous rounds darn near every weekend of the summer at a track somewhere....cam lobes still looked great when I pulled it out, roller lifter wheels still tight with no signs of wear, rocker arms were still intact with no sign of nedle bearing fatigue, etc...

There is alot of misconception about cams, convertors, etc...on this board from magazine articles and hear say. It's all about getting parts that work together. As far as gas milage....when a person is building that much power, and are worried about what they're gonna get city/hwy, then they dont need a motor like that as 500hp is a toy, not a 7yr/200,000 mile daily driven engine.

Mine was just over 500hp, idled all day at 800 rpm, but got terrible mpg since 1. I do not have OD, and 2. I had the enitre car optimized for it's purpose-goinig as fast as possible in the 1/4mi.
Timing was at a whooping 35* total, it was just as happy running 92 octane as it was 110 racing fuel, but honestly pump gas stinks like crazy when your in the lanes warming the car upto temp preparing for a run. Key is keeping the motor cool and jetting optimized along with head/cam selection for getting max power from the pump gas.

 

Great post IHI as allways. You allways "keep it real", i know that sounds stupid but I think it is true. People love to tell others that their dream/goal (500 HP N/A) is impossible. I am shooting for this right now. I am getting my motor in a few weeks. If you wanna know how it is done talk to IHI or thebigwelsh, he is the guy building mine. It is all forged eagel parts, with Trickflow heads. and 750 DP. single plane intake and all roller motor. This IS gonna be a 100% street car. Matted to a T-56 and a 12 bolt.

Gas is gonna suck but oh well, life goes on. At least on the highway I have a .50 overdrive 6th gear.

Oh well I gues to remark tword the origional post. IT CAN BE DONE, and relativly easily too. Just have to talk to SMART people that have done stuff like this before and NOT to people that have herd from a guy that had a friend whos brither's cousin said it was impossible.

Good luck, I will post pics, and dyno sheets when i get the motor.

 

One bit of info from experience, you've already got a solid foundation from the sounds of it with all the forged peices, definately buy the good ATI damper, i made the mistake of running a new stock balancer. Also opt for a 3 way lower timing gear. I had the 9 way to make cam degreeing easy, last year the 9 way was the latest/greatest, and now this year many guys racing are experencing the same fate I had-crank snout snapping off. They said the early 9 way timing gear was not chamfered and when installed on the crank it would run into/hit the radius on the snout and slowly cause fractures that would lead to failure. I checked my gear after I broke the motor down, and mine was chamfered so not 100% certain that is waht casued the initial lighting of the fuse, but suspect the stock damper to be the main culpret.

Those will be the 2 areas that I make sure I'll upgrade on the next mill along with the forged stuff since one day I plan to laughing gas the thing. If I were just going N/A again, I would have no 2nd thoughts about using stock cast internals again just from the good results I seen using what I had and how it all looked when I pulled it apart...cast is very forgiving in use and in failure, forged stuff tends to take many other parts out with it since it does'nt flex-it explodes

So long as your foots not in it constantly and you have OD, you really should be alright, not going to set records but fuel milage should'nt be too bad since the motor will be running 90-110% efficent. My car is purpose built to go straight and to do it quickly, and no matter what, I used it that way most of the time

 

Thanks for the comments so far guys...feedback has been great. I suppose if I go for the mini ram or a lt1 intake then its not really tpi but lets not split hairs... I am leaning in the lt1 direction to be honest. I have not selected a damper yet so thanks for that advice...Ask question first make decisions later right? Realistically I would love to find myself in the 500hp club but really anything pushing over 400 puts you well above %90 of anything on the road. Lets face it, if your driving a 12sec car around town your driving a *&^% fast car IMO

Does anyone know a good spot to get DDyno?

 

I burn alcohol so I burn about twice as much fuel as a gas engine would. I do a 1/4 mile pass at WOT but a total run from start to return to my pit is about 2 miles. I burn about 1-1/2 gallons of fuel in that time. Not the greatest fuel mileage but I'm also making a lot more the 500 hp.

Having a 12 second car at altitude takes a lot more than having a 12 second car at sea level. The engine doesn't make as much HP at higher altitudes.

 

Spend the money to have the block zero decked. Run a .039 or .040 head gasket and your motor will be much less octane sensitive.

Target 11.0-1 comp. A fuel injected motor can run this on the street without problem. Pick your heads before the cam. You'll want the flow numbers from the heads so that you can tailor the cam to the heads.

My heads have outstanding exhaust flow so I run a single pattern grind.

www.geocities.com/dzperf

 

I plan on having the block decked and it is at the machine shop already..I had been waiting on my splayed caps to arrive. Liking the advise so far, perhaps by feb I'll have this thing built and ready to go in.

 

hp vs Torq numbers really surprised me on my 383. I had the motor dyno tested before I ever put it into my car.my hp was 367 and my torq was way up there I thought, 433 foot lbs. I didn't expect the torq to be that much diff from the hp but I have to say I am not unhappy with it though lol.I had the car this year at the Car Craft show and drove it around the show with 90 degree temps all weekend and never once came close to over heating (one guy blew a head gasket), very streetable and one hell of alot of fun to drive. traction is def a prob with this amount of torq so keep that in mind for any racing, unless you get all h-po suspension parts and sticky tires.

 

I hear ya, these strokers put out some great tq numbers:
http://img.villagephotos.com/p/2004-...isdyno2005.jpg
http://img.villagephotos.com/p/2004-...nternetpic.jpg

But that is a good thing with heavy azz cars like ours cuz hp alone wont get us going very quickly.

 

^^^

Holy crap, are those your numbers with the specs in your sig?

 

Yeah, and it's the best sound'n diesel I ever heard LOL!! Told my buddy I shoulda pulled the motor out of the car and put it in my truck, woulda made some of the hills I pull alot easier

 

For what it's worth, I logged 20 miles per gallon on the way home from the Woodward Dream Cruise with my Minirammed 385.

I also cruised in stop -n- go traffic (not figured into the mileage figure above) for four straight hours, idling the whole time.

Oh, and get this: I pulled it onto the portable Livernois dyno at eleven mile, and put down two runs that hit a peak of 396 RWHP and 385 ft.lb of torque. Figuring drivetrain losses, that is approximately 460 HP at the crank.

The engine has not even been completely optimized in terms of tuneup, so I think that when I'm done, there will be 425 RWHP here, and that is getting awfully close to the magic 500 HP mark. If I do manage to pull it off, I will be sure to publish the dyno numbers as proof.

So there you go. I contend that you can achieve the 400 HP to 500 HP target on 93 octane pump gas, get decent gas mileage, AND have something that is streetable. It just costs a lot and takes a whole lot of planning and attention to details.

 

Ok so I curios then, can you throw out some details on your setup
ws6transam...Approaching 400tq at the wheels is quite impressive..

 

Hey guys. i am gonna be getting my motor in the next 2 weeks. Man I can't wait.

One quick quesion. Let me first say this is not a race car in any way.

The motor is all forged internals. (eagle and other stuff) What kinda N20 would you guys shoot into it "just for fun" kinda thing? I just wanna know,... this def doesn't mean I am gonna be trying it, or running, just curiouse. Thanks

 

phoronZ, LOOK OUT! your threads being hi-jacked!


dennisbernal91z, post that question in the 'power adder' forum.

 

Been on this board for a few years, and you begin to realize that the word "streetable" means different things to different people.

Not saying 500 HP isn't possible, but I believe personally, if I wanted to acheive that kind of HP on the street with a SBC, I'd go forced induction whether it be turbo or blower.

Otherwise, get more cubes. That way you can run a more street freindly cam. Just my 2 cents.

 

Sorry about the hijack, I wasn't thinkin'. Yeah I will post it over there.

As was said above. Steetable is a big gray word. My cam is def not gonna be considered streetable. But I am gonna drive it on the street. Not all day and night, but def around town and on the highway. I guess the kind of place you live really determins a lot of how u define streetable....anyone agree..?

(wish i had my cam spec with me)