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Can a 306ci create 400rwhp?

  • Thread starter Thread starter doobsstang
  • Start date Start date Jul 28, 2006

doobsstang

Member
Oct 4, 2005
92
1
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Pembroke, NH
Jul 28, 2006
#1
  • Jul 28, 2006
  • #1
I am thinking about getting an engine build by RNH Performance and wondering if 400rwhp is an attainable goal with a 306ci...Thanks. :SNSign:
 

VibrantRedGT

"STANGNET'S PENGUIN SMACKER"
15 Year Member
Nov 29, 1999
14,679
424
154
Boca Raton, Florida
Jul 28, 2006
#2
  • Jul 28, 2006
  • #2
If he can get 400 to the wheels, they will be rich SOB's. Figure a little over 1hp per cubic per mild application. Add a few percent more to a medium application. A full 12:1 compression aggressive combo won't even get close to 400 at the wheels with a 306.
 

doobsstang

Member
Oct 4, 2005
92
1
6
Pembroke, NH
Jul 28, 2006
#3
  • Jul 28, 2006
  • #3
Would low to mid 300s be closer or not even that high?
 

Car Nut

Founding Member
Jul 6, 2000
1,176
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37
Snellville, Georgia (Atlanta area)
Jul 28, 2006
#4
  • Jul 28, 2006
  • #4
Go with a 347. With the right h/c/i on a 347, you should be able to hit upper around 400hp. The key will be getting the right parts.

I agree with everything said above. Very good advice.

I'm strongly considering a similar setup, however, since I've got to meet emissions I'll be satisfied with 330 to 350rwhp. A new motor with all new parts (and finishing up with a good tune at a dyno) should offer high reliability and above average power.

It all really depends on how aggressive you get with the cam and whatnot. Do you need it to be streetable? If so, then there's some power you'll leave on the table. Just know that most engine builders are going to tell you what the motor will make at the crank, not the rear wheels.
 

1slow95

Founding Member
May 16, 2002
1,797
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48
ohio
Jul 28, 2006
#5
  • Jul 28, 2006
  • #5
Should be easy to do with enough boost....N/A, not so much. I figure mid 300's should be easy enough though with the right combo.
 

blksn955.o

Founding Member
Mar 15, 2002
3,263
0
66
st.louis mo 314
Jul 28, 2006
#6
  • Jul 28, 2006
  • #6
280-300rwhp and then put a 125-150 shot on it and you will make that easy.

N/A not without a REALLY good chunk of change prob. have to spin it into the 7k-8k range
 

94GTLaserRC

Squint as you approach, lest you be blinded by my
15 Year Member
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Ernan Says "here it comes... dushbag"
Jul 28, 2006
#7
  • Jul 28, 2006
  • #7
SURE IT CAN!!! Just slap a Vortech on the sucker (or some NOS)
RC
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jul 29, 2006
#8
  • Jul 29, 2006
  • #8
I got a thought or two

300rwhp is no prob for stock blocked na combos

325rwhp is not even outta line but requires a bit more effort

Now when talking about 350 na rwhp out of a 306 ......

1 the few extra cubes with blueprint and balance will help for sure
2 the parts are gonna have to work together really well
3 the compression being higher will help things along
4 the tune needs to be optimized

I see that goal as very attainable

but

you gotta make some specific plans and get help from peeps ... that have done it

Anything higher than 350 to the wheels on a na 302-306 is where drivability is gonna really start to suffer IMHO. A combo of this level is not gonna be all that great of a dd due to cam, compression, and it will be pretty thirsty.

Of course, if you are talking about a purpose built motor for the strip, that makes it easier as drivability or low end torque is not any issue at all since the focus is WOT only.

anyway ...........

Its gonna take more than GT40p heads, Cobra intake, and an e-cam.

Grady
 
C

cbarr300

Member
Jun 6, 2006
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goose creek, SC
Jul 29, 2006
#9
  • Jul 29, 2006
  • #9
I'm with grady..It is very possible.....but you'd HAVE to make sure all of your components work VERY well with eachother......

Not to mention it'd cost an arm and a leg.....and prolly two of your other fingers. I'm sure if you searched around though you could get the stuff for a fairly good price.

Good luck on your possible build up

Clay

EDIT: You could always stroke it.....as they say, "There's no replacement for displacement"
 

Grn92LX

Fidanza Man!
Founding Member
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Jul 29, 2006
#10
  • Jul 29, 2006
  • #10
Not hard at all...

http://www.corral.net/forums/showthread.php?t=80685&highlight=torque+monster
 

nazstang

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Rhode Island
Jul 29, 2006
#11
  • Jul 29, 2006
  • #11
i can be done, you just need to plan it right. one of my closest friends got 420ish to the ground with his 306. no nos or boost, it revs to the moon and got a throttle body you can stuff you head into. i believe he had worked twisted wedge heads and Victor 5.0 intake and edcurtis cam setup. sick sounding car, i hope to replicate it in my 88.
 

94GTLaserRC

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Ernan Says "here it comes... dushbag"
Jul 29, 2006
#12
  • Jul 29, 2006
  • #12
This car could not then be a DD could it?
RC
 

final5-0

Mustang Master
Apr 6, 2003
6,817
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79
DFW Texas
Jul 29, 2006
#13
  • Jul 29, 2006
  • #13
94GTLaserRC said:
This car could not then be a DD could it?
RC
Click to expand...

First of all, as always, I got a thought or two

This is a pretty max effort project IMHO ... I mean ... Look at some of this stuff and I think you will agree ... it took LOTS of cash AND this combo is the exception to the rule.

1) I am using the factory '93 block with a DSS girdle, an Eagle crank and H-beam rods, and Ross pistons(shelf stock, not custom). The machining was just the standard cleanup, nothing exotic was done(vibration, coatings, thermal treatment, etc.). The rotating assembly was balanced using a 28oz imbalance(wrong crank was shipped and he made it work) I hand fitted my JE rings.
2) TEA Stage III Renegade Twisted Wedges
3) CompCams Titanuim retainers
4) Holley intake is also TEA's full Renegade port job, with #s 1 and 5 welded to straighten them out
5) The cam is an FTI custom
6) Bassani 1 3/4"to 1 7/8" stepped headers with 3" collectors
7) factory T-5
8) I tune with a PMS

Just a comment on each point

1 Purpose built motor ... I'm not gonna be using a motor at that level to just get around town

2 Not your run of the mill, average set of TFS heads ...Lotta Cash

3 Those ain't cheap

4 Same kinda thing as point #2

5 This shows his commitment to follow Ed's recommendations which are all about ... results first ... and cash spent is NOT the top priority in situations like this one

6 Very spendy and hang LOW ... not the best choice for a street car

7 I mention this as it will help the dyno results but it ain't as tough as other stick trans choices that would show a tad lower dyno numbers

8 I could go on and on here ... but only a comment or two

a) He laid out the necessary cash for the equipment to be ABLE to tune it for the BEST results possible

b) Look at his post about tuning day at the dyno ... MAJOR CASH

Summing up ...... To my way of thinking ...................

Daily Driver?

Sneek it out on the street every now and then

You'd better believe it

Grady
 

Venom351R

Founding Member
Apr 27, 2002
4,548
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MAINE
Jul 29, 2006
#14
  • Jul 29, 2006
  • #14
just build a 347 insted of a 306 then you wont need as wild of a combo to hit 400. Porting the heads/Intake will help as well.
 

94GTLaserRC

Squint as you approach, lest you be blinded by my
15 Year Member
May 7, 2002
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Ernan Says "here it comes... dushbag"
Jul 29, 2006
#15
  • Jul 29, 2006
  • #15
Redline_RR said:
just build a 347 insted of a 306 then you wont need as wild of a combo to hit 400. Porting the heads/Intake will help as well.
Click to expand...
Hey....TRAVIS is Back!!!
W/B
RC
 

Black95GTS

Active Member
Jan 8, 2004
1,644
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38
Marlborough, MA
Jul 29, 2006
#16
  • Jul 29, 2006
  • #16
Definately, I bet this would do it:

C and C TFS High Ports
Chunky solid roller cam with 265ish at .050, 108 lsa
Edelbrock Super Victor Manifold
750 holley double pumper
a valvetrain that can support 70 hundredths of lift

Then you mill the heads until you get a compression ratio of 11:1.

Rev to 7500 and enjoy your 550ish HP 306.

Is it streetable? I would say no, its probably dog slow under 5K RPMS.

Bench racing is fun!

Adam
 

doobsstang

Member
Oct 4, 2005
92
1
6
Pembroke, NH
Jul 29, 2006
#17
  • Jul 29, 2006
  • #17
I was thinking 331 or even 347 but I have been lurking around here for awhile reading on them both and it is worrying me that people are saying things about wear on th engine with those. I want to go that big just kind of reluctant because I do not want to spend ther cash and have it die after 1k miles. Are they ok if you do it up right?
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jul 29, 2006
#18
  • Jul 29, 2006
  • #18
doobsstang said:
I was thinking 331 or even 347 but I have been lurking around here for awhile reading on them both and it is worrying me that people are saying things about wear on th engine with those. I want to go that big just kind of reluctant because I do not want to spend ther cash and have it die after 1k miles. Are they ok if you do it up right?
Click to expand...

We been through all this before

347's giving up the ghost due to using them for street cars is ...

internet and needs to be

Strokers are dandy for a street car

whether they be 331 or 347

Grady
 
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