Anyone build a 615 or 598 using the DART 20 Degree heads

July 27, 2018, 08:43 PM

racerdude2054

there has been long discussion and debates on other threads

for the same price you can make two choices

615 SR 20 with aluminum block
632 spread port with steel block

spread port motor will make more HP and run more MPH. Both of these combinations will run close to the same in ET

as far as the OP's original question. Dart vs Brodix on the 20 degree head... both are going to run the same and I would worry more about who I have doing the head work and putting the motor together instead of which of the two to purchase.

As far as fuel choice, gas all the way on those motors

I was always a big alcohol advocate for 10 years, recently switched 1 car to gas and now I am switching the other to gas

my opinion is a 598 SR20 or 615 SR20 with aluminum block on gas. In a dragster you will run 4.4X with that combination

July 27, 2018, 10:42 PM

WHOMPWHOMP

quote:
Originally posted by bbtommyd:
To each his own...running a 9 degree now never again i will stick with the SR20...

You're not happy with the 9* heads? Just curious why.

No sir been a very good motor...I run the shyt out of one when I race double quite often have it’s tongue hung out...but I have run both and am having another SR20 built now I just don’t see any advantage with a spreadport especially bracket racing...most SR20 guys are running very close to me and a few lighter ones are faster

July 27, 2018, 10:44 PM

WHOMPWHOMP

quote:
Originally posted by Spanky@Wilson Race Engines:
A really good 632 SR20 makes 1200 to 1230 on my Dyno. A good 12 or 9 degree makes 1270 to 1330. I have done both. A good spreadport motor will always out perform SR20 motor. Price is about 3k to 4K more depending on the head with a spreadport.

And once again your gone gain at least 30 pounds which is gone make um very close in ET

July 27, 2018, 10:49 PM

BLIND MULE 2217

quote:
Originally posted by racerdude2054:
there has been long discussion and debates on other threads

for the same price you can make two choices

615 SR 20 with aluminum block
632 spread port with steel block

spread port motor will make more HP and run more MPH. Both of these combinations will run close to the same in ET

as far as the OP's original question. Dart vs Brodix on the 20 degree head... both are going to run the same and I would worry more about who I have doing the head work and putting the motor together instead of which of the two to purchase.

As far as fuel choice, gas all the way on those motors

I was always a big alcohol advocate for 10 years, recently switched 1 car to gas and now I am switching the other to gas

my opinion is a 598 SR20 or 615 SR20 with aluminum block on gas. In a dragster you will run 4.4X with that combination

Actually a few of the 598-615 sr20 combos go .30s in good air. Whomp races with/against a couple on a fairly regular basis.

July 28, 2018, 08:19 AM

Cashflow

Which is better on the throttle stop? SR-20 or Spreadport and why?

July 28, 2018, 09:29 AM

RPROGAS

The question that started this was.....has anyone used the Dart 20 degree cylinder head and did it work successfully?

Answer:
Steve Schmidt built a all aluminum 622 for a good friend of mine (Dennis Blehm's Super Street '67 Nova) using Dart 20 degree heads with Crower stainless shaft rockers, trust me it is very fast. I don't recall the exact dyno numbers but it was well over 1100.

I don't want to debate if a spread port would be faster, I would be guessing what I do know is that this piece is very fast.

Before anyone asks the question, it was very affordable. It would be up to Dennis to tell you what he paid, not me.

Bob

July 28, 2018, 02:27 PM

Alaskaracer

quote:
Originally posted by Cashflow:
Which is better on the throttle stop? SR-20 or Spreadport and why?

Vern, give Dave a call. Last time I was at his shop he was finishing a sr20 combo for a super comp or super gas racer. Don't know specifics on the combo but I'm sure Dave has plenty of info for you to think about

July 29, 2018, 09:09 AM

RPROGAS

555
Got the dyno sheet on that all aluminum 618 with the Dart 20’s that I mentioned in the pm. 1285/951.

Side note.

He has a new/fresh/never run complete (not Schmidt) with carbs, ignition and dry sump all aluminum 648 for sale, it’s 1420/1000+. It comes with the dyno sheet and complete build info. Will not fit in his door car with current front cross member, not willing to modify so it’s for sale. Opps.....Did I forget to say “fire sale”?

Bob

July 30, 2018, 12:37 AM

Triple Nickel

Thanks for all the replies guys. I know the SR20 style stuff makes good power, was just specifically looking for info about the DART 20's.

RPROGAS that sounds impressive, best to date.

July 30, 2018, 08:15 AM

369dragster

quote:
Originally posted by Triple Nickel:
Thanks for all the replies guys. I know the SR20 style stuff makes good power, was just specifically looking for info about the DART 20's.

RPROGAS that sounds impressive, best to date.

I have a 632 with pro 20's and a steel block,weighs 1950 in the good air it went 6.98 @ 194

July 30, 2018, 10:26 AM

Kenneth

I like the Dart 20 degree head better than the Brodix. It is machined for bigger head bolt washers, the intake bolt holes fit a regular bbc intake manifold,and they are beefier for more porting room. I have a set of the Dart heads I did for a 615( also did the engine) that made a little over 1300 with one carb and cast intake.

July 31, 2018, 02:37 AM

Triple Nickel

Kenneth, that is impressive. Did motor go into a dragster if so what did it run best?

July 31, 2018, 11:09 AM

Al Alguire

Just for giggles we race against a 611" SR20 in NA10.5 class. Naturally aspirated 29.5x10.5 tire. The car has been 7.70's and over 176, pulling timing at the hit. Did I mention the car is 3300lbs too....There is a ton of potential in the right hands for sure. Just sayin

July 31, 2018, 11:32 AM

joeblow

quote:
Originally posted by Kenneth:
I have a set of the Dart heads I did for a 615( also did the engine) that made a little over 1300 with one carb and cast intake.

that's 2.11HP/cu.in

Wet sump and how much $ to duplicate it?

July 31, 2018, 12:13 PM

TOP38

quote:
Originally posted by Kenneth:
I like the Dart 20 degree head better than the Brodix. It is machined for bigger head bolt washers, the intake bolt holes fit a regular bbc intake manifold,and they are beefier for more porting room. I have a set of the Dart heads I did for a 615( also did the engine) that made a little over 1300 with one carb and cast intake.

To achieve that much power in that combo that intake was far from just port matched or the dyno is happy, especially if on just race gas (No Q16)! Not saying I don't believe it though, those are good heads. Hope you didn't buy the Dart statement that there new copper impregnated seats are OK with Tit valves and 55 degree seats BTW!

July 31, 2018, 01:48 PM

diceman1530

My SR20 632 has a dyno sheet of 1318 hp
but has only run 7.14 so far in a 1975 lb
dragster with a new fti convertor matched to it.
I don't put much faith in the dyno sheets anymore.

July 31, 2018, 02:20 PM

Kenneth

The 615 manifold is worked and runs on Q-16. Wouldn,t want to run anything else regardless what the internet gurus say. It is wet sumped with a vacuum pump and has a 2.25 Dambest carb on it. It runs 4.70's in 7000 DA at 2000 lbs. in a dragster. It could go quicker ,but customer does not want to rev it up. The Dart heads are bad ass. Also it does have copper seats in the heads. 55mm cam and .904 lifters.

July 31, 2018, 02:58 PM

TOP38

quote:
Originally posted by Kenneth:
The 615 manifold is worked and runs on Q-16. Wouldn,t want to run anything else regardless what the internet gurus say. It is wet sumped with a vacuum pump and has a 2.25 Dambest carb on it. It runs 4.70's in 7000 DA at 2000 lbs. in a dragster. It could go quicker ,but customer does not want to rev it up. The Dart heads are bad ass. Also it does have copper seats in the heads. 55mm cam and .904 lifters.

Sounds like a nice build. Hard to compare that DA with ones closer to sea level, the math doesn't work with that much adjustments. Not to mention the humidity factor.

Nothing wrong with Q for a fuel, but for me, to much agg, stinks and just not worth the added cost. If I need to go faster for any reason, small shot of NOS does the trick.

Yup copper seats is the way to go ,,,, I have heard that with a reasonable 50 degree seat that the Tit. valves will live without the copper seats.

July 31, 2018, 03:01 PM

TOP38

quote:
Originally posted by diceman1530:
My SR20 632 has a dyno sheet of 1318 hp
but has only run 7.14 so far in a 1975 lb
dragster with a new fti convertor matched to it.
I don't put much faith in the dyno sheets anymore.

Something is missing there and definitely not making anywhere near that HP level, assuming nothing is off, its more like 11 something HP!