Need your opinions and ideas

[eldabo]

Im getting a new motor built and its going to be a 406 dart eagle combo.In the future I want to put a procharger or turbo on it . I thought I would run low compression and make up for it with N2o untill I can save the money for the other .He says he wants to go with 12.5 to 1 and when I have the money just buy new pistons .I guess my question is how much power will be gained or lost with a say a 12.5 to 1 vs 8.5 to 1.? My combo now and how it runs on a 200 shot of n20.please give me your opinions.

350 stock stroke and block
10.8 to 1 compression srp domed pistons
A F R 210 race ready
Victor Jr intake
750 holley proform main body upgraded base plate and metering blocks
comp cam in take 600 intake 616 exhoust with 106 center line and 110 lobe seperation
comp cams 1.6 pro comp rockers
stud gurdle
fluidamper 6.in
shoenfield headers 1 7/8 steped
3 in pipes through magna mufflers
1.82 glide with brake
ford 9 in with 4.88 gears
28x10.5x15 mt slicks
car full race wt with me in it 3440 I weigh 240
track 60 feet short of an 1/8th
I run at that track 6.38 at 99 to a 6.40at 98

[eldabo]

Oh and he want to work on the heads poting and what not .

[dadnova]

Go with 10.8 compression with all the right stuff including forged pistons good for a Turbo, then add the Turbo when you are ready.

A Turbo put on a 10.8 to 1 engine will make a lot more power then one on a 7.5 or 8 to 1 engine. If you talk to the guys who are really fast, they are running higher compression engines to start with, read and do the research, in the last turbo performance shootout, all but one were well over 10.5 to 1 compression engines. I have seen them on as high as 13 to 1

I'm installing a 98mm turbo system on an 11+ -1 engine, the real issue is, the tuning window is smaller, less room for mistakes, that's why good instruments are needed, wide band, knock sensor and so on. I should be about 1300HP with only 14lbs of boost which also means I have plenty of room for more and as I don't need 30lbs of boost to be at the same level I am not heating up the charge as much, as 14lbs will be cooler then 30lbs.

Do lots of research, don't take my word for it.

[eldabo]

Hell yeah thats what I need and want a turbo. In the future I will have one or two of them .
Thanks for your input.

David

[BILTIT]

Compression would depend on what kind of fuel you wish to run before and after the turbo install. You can get away with alittle more after the turbo install by running a water/meth injection and a good intercooler.

[dadnova]

I am going to run E-85 for the higher octane and low price per gallon, plus due to the cool burn of E-85, an inner cooler is not needed as it will greatly reduce the charge temps.

[supernova]

I would build what you want the first time. Here's why.
If you balance the rotating assy with pistons for the n2o then change it to the turbo set up you will have to change the balancing of the rotating assy. Not only that but the cam is differant too. To do what you are wanting to do could cost a lot more money then you realize. It's like building 2 motors instead of 1 so keep that in mind when you decide what you are going to do.

I do think you should do a lot of research on any engine combo you are wanting to build.
You need to think about what it is going to be used for and think about what type of fuel you are going to run in it, if it is for street use I would build it to run high octane pump gas, if for strip use only I would build it to run race gas only, ect. ect.

Keep in mind , what you are going to do with it and research are the most important things to remember.

[eldabo]

I whent with a 12.5 motor because the truth is I only drive it around the block every now and then and to the track and its only 6 miles from the house.One tank sould last me two to three nights racing if I make three runs a night and thats about the most I could run unless it truck bracket night.

[ronnelldotson]

i looked at what you want to due and i think thank for that build you have to really have a goal. if you run the low compresion i dont think that you will be very happy trying to make up the diff with nos. i did it once cause i wanted a 174 roots style blower but didnt have the cash to build the engine and get the blower. when i built my 406 i only put 8.5 to 1 total comp and the blower cam. put it all to gether and i could tell that i wasnt going to like it as soon as i fired it up . it just sounded like trash and reved like it was a stock 305.lol. so i took it back out and put in some real pistons but i kept the blower pistons for later. and when i put the pistons in and fired it up i was in love. the only thing was i went to one extreme to the next i put in 13 to 1 pistons i figured that if i was going to be stuck with running race gas i should be getting the best bang for the buck. even though i had the wrong cam in the motor it eneded up being a good thing cause it was a lazy on its own but when i put the nos to it it ran so good i never baught the blower i baught a fogger. as for your turbo the other guy who said that a lil mor comp is a good thing as long as you dont over due it was right on. if you think about it like this when the turbo goes to fill the cylinder on an ultra low comp motor it will have to work a lot duing this unless you have a big turbo up around 15 plus pounds of boost. by the time the chambers are fool the cycle is over and u wont really take advantage of the boost. but if you go up to 9.5 to 1 or a lil higher it will respond a lot faster and you can run lower boost to save parts. it will make a bigg diff on what cmp u run with a strret motor will be the best and put your turbo on it. then u can turn the boost down with your waist gate and run pump gas and then when you want to go to the track or race it turn the boost up timing down and run some good gas you will be be fine

[eldabo]

Tanks for the reply .
I bit the bullit and went with
13.5 to 1
Dart block
block is o ringed
6 in rod
solid roller 1.6 rockers
Afr 210 ported and ploshed
and this cam


Any body wont to guess what the numbers will be ?Im going to the dyno this Monday.

[mytmouz]

620ish hpwise...