AFR 205s + ERL 427 In the works

**GTO1_OHIO** · 04-02-2011, 07:02 PM

This build really started a year ago when I had Tony port my AFR 205s and my Fast 90. It ended temporarily in August when I started blowing smoke out my tailpipes during the Ames Performance Pontiac Nationals. A leak-down test found that the #8 ring was bad and #3 wasn’t too far behind. The thing was, the results that I had gotten on the track were showing that the work Tony had done for me would have easily put me in the 11.2s or better with better DA in the fall. My PB to-date had been 11.49.

So I came down to two options, repair my LS1 stock bottom and get to see the results of Tony’s work as originally intended or go to bigger cubes. Then I realized that I could do both. After searching, I couldn’t find very much posted on AFR 205s on large cubes, specifically on a 427. So that’s what I decided to do, max out the 205s and put Tony’s work to a really “big” test. I selected an ERL 427 LS2 short block as the new base to build on. That was the easy part of the build selection. To do this right, however, I knew that I was going to have to have the right cam. I decided to go to Ed Curtis to find the right stick to pull together the marriage of the larger cubes with what many would now say would be undersized heads.

Another thing working against me is that my entire setup was built for the LS1 block and now these components that had work very well for me in the past would restrict both the intake and exhaust. The question is just how much … hopefully it won’t take too long to find that out. I do know two things, regardless of the outcome this build will be the slowest my 427 will ever run and that my 11.49 PB will be history.

The build is being done by Rich and Erik Johnson of BackStreet Performance. BackStreet is the shop that prepared the C5 of Brian Nutter (Weisco) for the 2010 Holly LS Fest, where he placed 1st in the high noon shootout, 1st in autocross comp tire, 2d in the 0-60-0 ABS comp tire and was runner-up for the overall Grand Championship title.

Here’s what I’m working with from last year’s head work
• AFR 205 head milled to 61 cc and ported by Tony Mamo
• 2.020 and 1.600 lightweight REV valves
• PAC Racing 1221 springs installed 155 on seat
• Morel Hydraulic Roller lifters (5206)
• YellaTerra Roller Rockers
The rest includes
• Kooks 1 ¾ Headers with catted mids
• Borla dual exit exhaust 2.25 pipes
• Svede OTRCAI
• 90mm Nick William TB
• 90mm Fast Intake ported by Tony Mamo
• Fast LS1 fuel rails
• Lingenfelter High Flow fuel Pump
• SLP underdrive pully
• Katech Belt tensioner
• Meziere Electric Water Pump
• MSD LS1 Blaster Coils
• Magnecor 8.5 ignition wires
• 42 lb flow matched injectors
• Manley LS2 double timing set
• LS6 ported oil pump
• Precision Industries Vigilante Converter (3200 triple disk)
• Rossler Terminator II Transmission
• Meziere flexplate
• Diff Technics 3.73 gears
• Harrop Diff cover
• Derale Atomic Cool Transmission Cooler

The AFR 205s, as ported by Tony, produced the following flow numbers. Based on other flow numbers I’ve seen, they compare to the intake numbers of an AFR 215 and the exhaust numbers of a AFR 225. ...that's on the 3.9 bore, on the 4.125 they'll be higher.

Intake
.200....154
.300....216
.400....268
.500....296
.550....305
.600....302

Exhaust
.200....132
.300....190
.400....222
.500....238
.600....247

The short block is a 427 ERL dry sleeved LS2. Compression will be 11.5:1 The engine components and specs are shown below

And finally the FlowTech Induction cam. I’m not sure Ed has published the specs for this cam so I’ll have to see if he comments. For now I can tell you this … it’s not a Comp. The power band is “roughly” 3000 to 6200 for 400-427 CID. Last year’s ring problem IMO was caused by my 7200 rev limit, I didn’t want to go there again and with the 427 I don’t need to run the RPMs that high.

The LS1 has been pulled and stripped of parts, the engine compartment has been cleaned and repainted as needed.

The heads were sent out to be cleaned and tested for leaks just to make sure there was no damage done last year. The results were that they are as good as the day I received them from Tony. Just as clean now too.

The lifters were sent to Ed Morel for inspection and they also came back with his good to go.

The build-up on the 427 will begin this week. Time will tell what the results are ... Tony and I already have waited a year to see these heads do their thing.

**JAX04** · 04-02-2011, 09:07 PM

Ummmm.......................................

Noice!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

**mark21742** · 04-03-2011, 06:31 AM

Looks like I'm not the only one trays been busy. Looks good!

**Texas Jack** · 04-03-2011, 03:33 PM

The spec sheet sure looks good and so does the block and bottem end, not to mention those heads ( they are a work of art)!!!! The cam specs I hope you will reveal, another interesting build for sure! Lunati has been around from the beginning, good choice. One more build I will be following.

**GTO1_OHIO** · 04-04-2011, 04:36 AM

Originally Posted by Texas Jack

The spec sheet sure looks good and so does the block and bottem end, not to mention those heads ( they are a work of art)!!!! The cam specs I hope you will reveal, another interesting build for sure! Lunati has been around from the beginning, good choice. One more build I will be following.

Ed just let me know that he'd like to keep this one under wraps from his competition. What I can tell you is that it is his MAX-AIR 16 grind that in his words has been "tweaked".

From Ed's site:

MAX-AIR Series Camshafts
Serious Performance Usage
The highly successful "Max-Air" series camshafts are for serious performance usage only. These are the camshaft designs the record holders and class Champions are using!

Top ten racers know what they need and these are the bullets they use!

These profiles require very light weight valvetrain pieces and a ton of rear gear ratio for best performance.

**Texas Jack** · 04-04-2011, 05:27 AM

I will check that out, your running with the big boys, can't wait to see your new times!

**GTO1_OHIO** · 04-25-2011, 04:20 PM

The engines pretty much ready to put back in and hopefully we'll have her cranking soon.

We finally had some luck. This weekend we found out that the 7.350 pushrods we used in lasts years build were perfect for this build also. Erik at BSP added his usual extra touch with a some silver high temp paint on various engine parts as well as on all the accessory brackets. The motor should look a lot cleaner when done.

and to let there be no doubt, ERL has left its mark on the build

We decided to upgrade to a Manley LS2 double roller timing set as well as a Melling oil pump and had no clearance issues with the timing cover.

The only part that we found that we needed to replace was my flex plate which had a crack between two of the teeth. We went with a neutral balanced SFI 29.1 Meziere flexplate. It is a one piece design machined from 4340 round bar.

**cammed goat** · 04-25-2011, 05:00 PM

Too bad that motor won't be seen once back in the car. Looks so clean!!!

**Texas Jack** · 04-25-2011, 06:54 PM

Sounds like a well thought out combo!!! What...... 600hp fly wheel? Nice.......[understatement].

**GTO1_OHIO** · 05-03-2011, 07:09 PM

Almost there.

Shooting to be ready for the Columbus Racing track rental on the 13th. So maybe dyno numbers early next week.

**cammed goat** · 05-04-2011, 09:00 AM

**Texas Jack** · 05-04-2011, 01:07 PM

pretty!!!!! Bad Ass!!!

**qwkgto** · 05-10-2011, 04:25 PM

So do i get to see this mod in person this friday? did you get the right ls2 cam sensor.....one in pic is not right..

**qwkgto** · 05-10-2011, 04:29 PM

Originally Posted by Texas Jack

pretty!!!!! Bad Ass!!!

he always goes for the throat with his mods,if I were NA id look out... I see new records being set!!!

**GTO1_OHIO** · 05-11-2011, 08:10 PM

Start up video

**GTO1_OHIO** · 05-11-2011, 08:18 PM

Dyno Video

**GTO1_OHIO** · 05-11-2011, 08:19 PM

Baseline numbers 489.29 rwhp 475.52 rwtq ... will be back after I get a few miles on the engine

**Texas Jack** · 05-11-2011, 09:52 PM

Russ that is very stout sounding and performing rig, 600 flywheel was close. Bet you will be setting some records in the NA class. what a nice ride and tuned so well it is still a street machine!

**Texas Jack** · 05-11-2011, 09:55 PM

Originally Posted by qwkgto

he always goes for the throat with his mods,if I were NA id look out... I see new records being set!!!

For sure!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

**GTO1_OHIO** · 05-12-2011, 04:12 AM

Originally Posted by Texas Jack

Russ that is very stout sounding and performing rig, 600 flywheel was close. Bet you will be setting some records in the NA class. what a nice ride and tuned so well it is still a street machine!

What's really amazining is that's pretty much my tune from last year. Only changes made were the adjustment for the larger injectors and you can see between the two run in the dyno graph we took away some fuel up top. That little adjustment up top gave us 9 more at the wheels. The car ran perfectly with Ed's new cam ... we were totally surprised. We thought there was going to be some major tuning required to dial it in. What we did expect was the smaller heads choking her at 6000 ... but the cam's power range is only to 6200 so were pretty much right back at the original stock readline as opposed to the 7000 I ran last year....And I think that's a good thing. lol

I think once the motors broken in and the rings seat we'll get that 600 flywheel with our next round of tuning.