Pseudo racing engine surprise

[randy331]

I thought a few may be interested in this combo I put together with some stuff I had sittin around the shop.
The idea was to just build something that would make 450-475 HP ( the reason we named it pseudo racing engine) and run 6.60-6.70 1/8 mile that wouldn't be hard on my rear bumper, and I could let others drive bracket racing some.

The combo is,
1.46" venturi x 1.69 throttle bore braswell carb.
GMPP vortec bowtie single plane intake, (un-ported)
GMPP small port vortec bowtie heads just as GM sent them with 2" intake/ 1.56" ex manley valves
4.031" bore x 3.75" stroke 383 cubes
factory GM block
Eagle forged crank and rods
Manley 2 valve relief flat top pistons 1/16 1/16 3/16 rings 11.4 comp
oil pan from competition products fits 70 nova chassis
stock oil pump
comp cam 236*/248* 108* lsa lobe lift is .380" in .367" ex currently with 1.6/1.6 rockers with hyd roller lifters
1 3/4 chassis headers, but was dynoed with 1 3/4 x 1 7/8 step dyno headers

both 1.3 and 1.6 rockers were tested on dyno, along with cam position for best power curve.
HVH 2" carb spacer was tested.
Amsoil 30 w break in oil.
100 LL av. gas on dyno and in car.

Here's the best pull of the day

rpm HP
3500 328
3600 334
3700 342
3800 350
3900 359
4000 370
4100 381
4200 395
4300 408
4400 421
4500 432
4600 444
4700 456
4800 468
4900 477
5000 484
5100 490
5200 495
5300 501
5400 506
5500 510
5600 514
5700 517
5800 521
5900 524
6000 525
6100 522
6200 519
6300 518
6400 515
6500 512

Here's a video of the best pull of the day.

http://www.youtube.com/watch?v=bQVHXHQu78c

We were very surprised it made that much power. 525 HP from an un ported 180 cc head is more than we expected.

We put it in my nova @2950 LBs. with a 4.56 gear (highest gear I have for it) and a too high of stall converter and hauled it to mokan and took a couple passes.
It ran a 1.369 60' 4.036 330' 6.383 @105 mph 1/8 mile 8.436 @ 118 mph 1000' 10.24 @ 123 1/4 mile

I thought it would get by on just the outer springs I had sittin here but it didn't have enough spring for the hyd rollers and it wouldn't go past 6700 rpm so the 1/4 mile mph was down.

Put the inner springs back in on just the intake and it would go to 7200 or so and ran 127 MPH the next week. It was race day and we were entered in 2 classes so no more et chasing and we had to foot brake in both classes we were in. But even foot braking it ran 6.44 1/8 mile. The other class was 1/4 mile but low et dial in of 11.00. My son won that class finish line driving cars slower then 11.00 dial in. I went out buy back out in my 1/8 mile class. LOL

Figure in good air with a bit less stall and maybe a 4.30 gear and some tuning, this simple combo could run 10.00s maybe even break into the 9s.

Anyway it was raining here today so I thought I'd post it in case someone was interested.

Randy

[wyrmrider]

nice randy
the low end with those heads seem to work
and max power at a reasonable rpm for those lifters
cheers
I may even watch the video

[bigjoe1]

That is just amazing ! It just goes to show you how many UNDER ACHIEVERS there are out there when you go yo the drags,


JOE SHERMAN RACING

[dirtracr5]

We've made really good power with the vortec bowties. 500hp and 500tq with a 2bbl carb even.

[novadude]

This really makes one wonder why more aren't using those vortec bowtie heads. Very impressive for out-of-the box castings with a good valve job.

[lada ok]

Do you have enough carb

If I work out the metric sizes of barrel and choke, that = 43 / 37 mm Is that 1 x 4 barrel ?
When you think that C & D type Jaguars used 3 pair of 45 dcoe webers, I think the chokes varied from circuit to circuit, a guess would be 36 - 39 mm on a 3.8 lt & 4.2 6 cyl
I can't remember the cam timing, but not a lot more if any and max rpm was about 6800

[randy331]

Very impressive for out-of-the box castings with a good valve job.

I didn't do a valve job. It's the valve job GM did. I bought the heads bare and bought Manley valves. I didn't even lap them. All I did was bounce the new valves on the seats with some dye to make sure the contact pattern was ok. Then cleaned them and put them together. No other work on the heads at all.

Randy

[Travis Horton]

Very cool, Randy! I was wondering why the car wasn't standing on the bumper. I was going to stop by and say "hi" but I was kind of busy racing. Your son did great. I was telling my buddies about your head/cam experiences on your other 383. They were impressed. Next time you're down I'll make sure I come see you!

[70imp355]

Wow randy thats some amazing work u r truely a pioneer n sure put alot of those bigcam big heads preaching guys to shame.

[MELWAY]

Randy do u mind sharing intake pt no. Do u thing the bow tie intake is better that the vortec super victor?

[steve cowan]

hey guys,here is another example of a few guys who get the job done,my recent build is a 383 sbc dart heads titanium everything ,makes 532hp @ 6800rpm what a joke i have got nothing on you randy,i read posts from you,big joe and melway here in australia and i am not trying to piss in your pockets because what you guys do is give me motivation to try harder and look outside the box and that i thank you guys for.

[groberts101]

it's all in the combo of parts, assembly, and the overall tune. My little Edelbrock RPM heads only have a near 2.2'ish inch MCSA and did 563 FWHP on my 383. Having a camshaft under 250 degrees opened a few eyes once the paper was printed out. I still remember wincing the whole time too because everyone kept telling me that my piss-poor choice in polished SIR rods would eventually let loose on me too. They were wrong.. and some additional stereotypes were broken.

[novadude]

Very impressive for out-of-the box castings with a good valve job.

I didn't do a valve job. It's the valve job GM did. I bought the heads bare and bought Manley valves. I didn't even lap them. All I did was bounce the new valves on the seats with some dye to make sure the contact pattern was ok. Then cleaned them and put them together. No other work on the heads at all.

Randy

That makes it all the more impressive!

Seems like the small port Bowtie vortec is a real "sleeper" in the RIGHT combination. This head is probably often overlooked by folks chasing a big CFM number as the only criteria for cylinder head selection. The GM guys that designed this part likely knew a thing or two about how to design ports and chambers.

[randy331]

Melway, the part # on the intake I have on Pseudo is 12486574, but the current one listed by GM is 12496822. Not sure of the difference if any.
CGT, on here is a GM parts guy, maybe he knows.
As far as better than the SV I think this one is very similar to the 2913 SV, but smaller than the 2814 SV, so the cubes/rpm would dictate which is better.

Travis, come over by the trailer any time. I'm thinking about racing down at Mokan on one of the April big money days. 25 or 26. May go back to the 1.3 rockers and run it on just the front 2 barrels to try and slow it closer to the 11.00 low dial in limit if we run sportsman.

Lada ok, the carb is just what I had here and it foot brakes good with that carb. Bigger is likely worth some power.

70imp355, not sure on the pioneer part, but I do think there is a lot of over cammed, over headed, under convertered combos out there.
This engine makes peak HP at 6000 rpm and the current converter stalls to 5800 when the tranny brake is used. Sent the dyno sheet to coan and they said 5500 stall. That's more than most would think it needs for lowest ET with that power curve.

I got 4 other converters here I could try. I'd say the 7" one is out LOL, one is a street 10" probably not enough stall, one is a 9" I just had an anti ballooning plate added so I can try it, and I have an 8" bolt together I'm gonna change to try and target 5500 rpm.

But first I took the valve body off and am gonna increase the size of the converter charge circuit to try and lower stall some that way and it may tighten it up down track some.

Randy

[CGT]

I believe the 12496222 GMPP, and the 2913 SV are the same manifold. Randy, surely your not going to leave that thing in unported, unrefined form? Any plans for recamming or head or manifold work? Think that thing would run better in that rpm range with less exhaust duration?