Great looking car... sweet setup.

With a 2900 stall and 10.4 pass for a street car is moving...

That CAM IS HUGE !!!


Happy to see you can still drive around town with that setup... and run killer times at the track.

That is my goal!

Of course my cam is smaller... 240/244 610/614 112LSA

 

I have a couple of questions for C3 Stroker

Engine combo:
Carb - Quick Fuel 950
Intake - World Motown, fully ported
Heads - AFR 210 Eliminators, competition ported
Cam - 250/254 dur., .720/.675 lift
C.R. - 10.4 w/ JE Aluminum pistons

Some engine shop built this for you, but did they explain why they went with more lift in the intake than the exhaust? Also why the low 10.4 C/R? From the dyno sheets what was the rpm where you had peak TQ and HP? I'm just trying to learn a different builders ideas.

I had the Art Carr 3500 stall 9.5 inch with my 427. It was kind of fun because it got you right into the start of the power range.

It seems like most all of us here on the forum got very similar heads and solid rollers all within a few CFM and duration degrees

 

No hijack meant here, but I will address briefly some of your questions for all fellow motorheads..

This engine was built by local builder W.O.T. Inc. (friend Neil Clayton) who for years competed in PHR's Engine Masters Challenge. I asked him to build mine similar to the criteria for their competition, as this would make the perfect hi-perf street/strip engine.

Since we were on the same page, I specified pump gas friendly C/R (approx. 10.5 to 1), heads to support 600 hp (AFR 210's fit the bill), and the appropriate carb (950 cfm).

The builder's expertise took care of the bottom end, using lightweight components where advantageous, and forged stuff where necessary, and other secrets he wouldn't tell (competition in EMC is fierce!). Otherwise, it was a basic build.

T&D shaft rockers w/1.6 int. & 1.5 exh. ratios were used hence the higher int. lift.......dyno tests proved slightly higher hp gain. Also, the "bubble" type air cleaner used gives more hp than even the K&N open top.....that's why you see them in the mag. pics in the dyno competitions. Having a DTS dyno in the shop is a very valuable tool!

The cam is a custom piece, the last component spec'ed for the engine....and it really is mild for the engine it's in. Peak HP came in @ 6500 rpm, and peak TQ @ 4800 rpm.......streeter's delight.

I wish I had your Art Carr converter.....I'd probably go 2 tenths quicker (if it hooks!)

 

Got love a solid rollers cam specs....

of course you have to adjust the lash...after some many passes or driving miles. No biggie though. I did it on my old camaro with a solid roller.


ANY MORE BIG INCH SBCs out there??

 

I did some quick calculations. you have massive lobe lift of .450 inches. During my initial test fit assembly Every rod hit cam lobes. This is even using a small base (.920 inch diameter) circle billet steel cam with .420 lobe lifts I had a set of 8 1.65 RR so I used them and bought a set of 8 1.7 roller rockers to end up with .685 intake and .714 exhaust.

My 434 can run on 91-93 super unleaded even with 11.8 compression. I kept my compression high just as a test. I figured that if it had detonation problems I would just buy bigger CC heads. I wanted to make a TQ monster and the only way to do it is to have the max compression that your fuel can take.

I've just been contracted to build a 421 ci 3.875 stroker sollid roller drag motor to run on E-85 fuel going to use an alki 750 demon carb. Or 110 leaded Sunnoco with a gasoline carb. Brodix -12 272 cc intake heads 54 cc cambers and get 13.8 compression.

I'm doing some calcs on the cam duration to have peak power at 7800-8000 rpm similar dirt circle track motors are using 260-264 Intake and 262-268 E with .780/.820 lift and 105-108 LC 800 hp is the modest goal.

 

it's not big by todays standards but i have a 396 sbc. just drove it for the first time last night. working out a few bugs in the 200 4r but it seems to run as well as it sounds. after a few short runs it looks like i am going to be very traction limited. the build specs are 10.5 to 1 comp, forged eagle assy, srp -5 cc flat tops, new version afr 195's milled to 72 cc's. weiand team g intake port matched to 1205 gaskets, custom crower hyd roller 236 240 @50 .594 lift on a 108 lsa. demon 850 annular. ( full of trash out of the box but worked very well after cleaning ) 200 shot of nos just in case i find traction. this thing seems to be very tourquey and really comes alive at 3000 rpms. throttle response is great.

 

.....looks like I left some horsepower on the table with my compression ratio.....you running more duration to do this? I was judging by my previous engine, at 10.9 CR, I had to run Sunoco 94 to be really happy. But, cam duration was only 230 @ .050. Thanks for your real world info....I can almost see my next engine......

 

My previous 406ci was near 11:1 lets say between 10.5 and 11:1 and it would run on 91 octane with 34 degs advance. It made 550HP but that was on 94 octane to be safe. It's the cam duration you are looking at, the DCR.

My current 427ci is about 10.6:1 and I run 91 octane in it too, it has a cam with over 250 duration

 

You find the graphs stating the % change in hp & tq as compression rises. It follows the law of diminishing returns. 10.5 - 11.5 might only be 2% gain. You might say to your self that 2% is only 12 hp on on a 600 hp motor. but it is that additional 2 % across the rpm band TQ that you feel in the seat of your pants.

From the comp Cams Lobe book I'm running the "RT" series lobes. Very aggressive ramps.

Advertised duration of cams means nothing.

.050 Advertised duration of cams puts cams on a level perspective.

.200 Advertised duration of cams tells you how steep the ramps are.

A common street roller might have 250/256 @ .050 and a .200 of 148/152 a "RT" 250/256 @ .050 and a .200 duration of 30 more degrees


So the cylinder is filled more than it's wimpy lobed street roller

 

If you just change the compression ratio and nothing else there isn't much gain.

You change compression ratio to match the cam and heads etc. so a 10.5:1 cr motor with the correct cam for street or strip will make certain amount of HP but an 11:5:1 cr motor will allow you to run a bigger cam and therefore you are going to make big gains in HP. It's all about matching parts correctly and that is where experienced engine builders shine

 

.....correct; a higher CR will allow a bigger cam, but the higher duration would have put peak power at a higher RPM than I was shooting for......matched parts is the key

 

C3 Stroker,

Nice set-up. What kind of automatic are you running? What was done to it to support these HP levels?

Thanks

 

Turbo 400, built by Rossler to sustain 800 horsepower.

 

Thanks

 

with a 2900 stall... thats pretty good times with a smaller stall.

What is your 60ft time?

1.7-1.5 ?

 

Quickest has been 1.50.......that's with a 2000 rpm footbrake; the converter immediately flashes to 4300 rpm.

Here's the timeslip:

 

Not a very big inch SB, but I cheated and put a twin screw SC on my 406 (it's a necessity at 6000ft). Just under 700hp & 750lb-ft. No roll bar, no track times, but still scary fast...

With an OD transmission and EFI, I get in the mid-20s for mileage. I'd get more if I drove more conservatively, but I just can't seem to do it.

 

zman, in a perfect world, id have a motor just like yours.... one of the NICEST motors on the forum easily

 

Very Nice

 

Z-man, any threads on that supercharger install? What fuel injection, what distributor? That is way cool.
Bee Jay