[nskeeter99]

OK I have an 81 Datsun 4x4 that had a 305 in it. well that died and I'm going to be putting in a 400. the truck has a 700r4 will have 4.88 gears with 33s right now 35s in the further maybe 38s. this is my build plan at this time. sbc 400 patriot performance vortec heads 185cc runners 202 1.6 valves. edelbrock air gap intake. my cam choice is the comp cam 268. i have dyno software not desk top dyno it engine analyzer. any Way show the 268 as have the best all around hp and tq. now i was wondering what the experts here think. now what i need is enough low end tq to maintain highway speeds in overdrive,with enough power at the top to scream though the mud. now this is for the racers on here. i was thinking that i could build it like a street strip motor. i open to other suggestions if you dint like my build expert the head Allready got them, was not planning on a stall but also open minded there to if have anysuggestions.

Skeeter

[DoubleVision]

I`ve said it a 1000 times before. You get what you pay for. Compare prices to top name brands.

[nskeeter99]

ok i dont get the you get what you pay for deal, i wasent asking for a cmbo on the cheep just if my build sounds good and what besides the heads would yall change?

[cool rockin daddy]

skeeter,

Do a forum search on Patriot heads. Chinese cast.

You are all over the map on your request. You want a street motor with lots of low end grunt but want it to really scream to get through the mud. Kind of mutually exclusive. There are also many "recipes" for SBC builds in the data base. Asked a 1000 times before and answered a 1000 times before. You have asked a loaded question that can be answered a million times before and all the answers can be right or all can be wrong depending on your point of view. Stop and think about it. You don't want more than a 750 cfm carb for the street. 650 would probably be better. Street engine cam would be best with no more than 230 degrees duration, depending on your gear or trans. You really don't want more than 180 cc runner volume in your heads for the street, maybe could go to 200 max on a 383. You want a dual plane manifold for the street. You want 36-38 total degrees of timing with most of it in by 3000 rpm.

How much money you got? What does "street" mean to you? What does "streetable" mean to you? Everybody has different opinions on what these terms mean.

Be creative. The above are the guidelines that 99% of street engines are build with. Choose the manufacturer your choice of each component that will stay in those guidelines. Ask the manufacturer or vendor where his castings are made.

[nskeeter99]

ok let me back up some and give some more info on me. I know how to rebuild an engen have rebuilt a few it when you giving them more power i understan how i have add intackes and even cam. i learned to port to polis my head on the datson befor the origanl engen left. however most of my knolege of good parts are from reading, not experance. i was hoping to get some input from guys who have put this stuff togeter and run it. the parts i put togeter are from reading then putting them togeater on engen analyzer. i did do some reserch on the patrites befo i got them about 60 good 40 bad. however to get a set of vortec syle heads with big valves 5 angel valve job yada yad yada. for 500 bucks to my front door just got to put them together. i was think it could be built street strip styel since it gets driven on the street and in the mud will be all out like on the strip. now my strret thought are to be able to dirve to the trial and to work when i wont to. just like the 268 cam i used according to the soft ware with the rest of my combo it give me the best avarge hp and tq. other cams gave higher peeks but less avarge. so that is why im asking the real world paper is one thing but you experts who have done it are another. if i get 3 dozen diffrent combos thats fine will give me other options that i know people have run

[sgo70]

Lots of options here, not sure how accurate they are:

http://www.ryanscarpage.50megs.com/combos1.html

Sean

[ap72]

Reminds me of a redneck spelling bee.

You're going to need to have another $400 of machine work done on those ehads- that's why people say stay away from them- in the long run they'll cost you more. As far as power goes you're going to need to run a cam with around 220/225 duration or even a hair less. Its not going to scream up top but you need somesthing that can pull those big tires with an OD and only 4.88 gearing. I would also stick with about 9.3:1 compression- many engines run more but not engines that turn 38" tires on the street.

[nskeeter99]

what eles do i need to do to the heads. they driled the steam holes, it has the big valve and screw in rocker studs. if there is somthing you think i need done let me know i dont wont to take it apart again.turning big tires is one of the reson i went with the 400 just cant put a big block in that hole was hoping the cubes would help make up some of hte bottom end right now 35s are the plan if i do 38 they would prbley be only run for off road only on road to get me there. those things are too much money to runn on the street like that.

Skeeter

ps in a few years i do wont to strock it but got to start small

[nskeeter99]

so the comp cam 268 should be a good one with 218 duration then? being that is below your 225 suggestion

[ap72]

a LOT of people like their 268 cam. It won't give you max hp but it will give you a lot of useable torque in that 400. As far as the heads go ask the machine shop to check them over for straightness and such. The 35"s won't be too bad as long as you pay close attention to ring gap and cylinder prep. I also recomend switching to synthetic oil after your first few changes and running an oil and trans cooler. I would also suggest a 190º thermostat. max power will be had with a colder one, but that temp will really help your engine's longevity.

For this particular setup keep a few things in mind- durability is a greater concern than in a car because of the high loads put on the engine, and low end torque is far more important than power numbers over 5,000 RPM.

[gmcaseyf]

run a dual transfer case set up for you low end power and rippin through the mud. 4.88 gears should be plenty low for 38s. power isnt gonna mean as much as gearing with your application. speaking of that, why a datsun????

[nskeeter99]

The Datsun is what i started with i found it about 5 years ago for sale got it for 600 bucks. I was looking for a yota at the time but was not going to spend the money they wonted for a 4x4 yota. plus the Datsun was a true extended cab so i could move the kids in it. Anyway have never finished it. tcase wise I'm using the tcase from the Datsun which is divorced type. i have a back up but once they go will go with a 205 and maybe late the 205/203 set up. the good tq. running the engine analyzer software showed higher peek hp on other cams but the 268s average was better it even does better than the extreme 268.

[nskeeter99]

OK while reading other post on here, i cam across northern auto parts link. anyway they have a decent price on a rebuild kit and this is one of the cams that i can get with the kit. it actually peeks a Little higher than than comp 268 on hp and tq. the average was a Little higher hell even the vac was higher according to the software. What do the experienced folks think?
http://www.northernautoparts.com/Pro...ctModelId=4241

[ap72]

Its not a bad cam at all- a little lazier than I'd like but t should give you very respectable torque.

[nskeeter99]

what do you mean by a littel lazey?