[ARP Part Number For L28 Flywheel?]

The matching washer to go with the ARP RB26 flywheel bolt (arp #102-2801) that Tony D mentioned is 

 

ARP part # 200-8710, you must order 6 of the washers.

 

Note: The inner diameter chamfer on the washer goes against the head of the bolt.  If you do not do this, the washer may cut the head of the bolt off.

 

I have not tried this yet, so I do not know if the clutch will clear bolts with washers under them but I think it will work...Ill try to post more when I get it together.

 

Thanks Tony.

[N42 head questions]

Here's the thing tough my head i had before is an N42 with an internally oiled p90 cam. The N42 im gettting from James doesnt have an Oiler, so what im asking is can i swap in the p90 cam on the N42 Head im getting. or should i find an oiler will the compression ratio lower a lot. I have the old head's rockers and cam towers

 

So you are going from a internally oiled n42 to a internally oiled N42 right?

 

Just swap the cam, rockers, valve stem top caps. Leave the towers in place unless there is a real reason not to. Measure the thickness of the new head from the deck to the surface the valve cover bolts to, if its within spec, no cam tower shims are required. Check the cam wipe pattern on the rockers, adjust if needed, odds are you won't have to adjust anything unless the new head was super shaved or your old head was shaved and the new head was not etc. But if both heads are close to stock, it should be plug and play. If you are unsure...a good machine shop should be able to help you figure it out.

[200+ WHP NA build]

 

Try THESE numbers for 'runs and doesn't blow apart guidelines' (and we haven't actually floated a damn valve yet):

 

12,500 for an L20A

9750 for an L28

8700 for a VO7 Stroked L29

 

And in EVERY case above, we stopped because either the tachometer didn't log higher or we were plenty past the power peak that we've determined further increase would be pointless other than to know we just need a bigger cam or more boost to make even more power at the higher rpms.

 

8K with an L24 isn't even getting STARTED as far a 'maximum allowable RPM's'!

 

Tony, what are you guys using to keep your timing chain tension happy?

 

I recently had all of my exhaust valves kiss the pistons. This happened when my throttle linkage became stuck causing the engine to idle at 4k. I drove to a open late Walmart to buy an allen wrench to fix the linkage. On the way, the engine saw extended higher rpms with more abrupt than normal street rpm changes. After the linkage was fixed the valve train was louder. Found 2 cracked intake valve spring retainers, which is odd because none of the intakes touched the pistons. Pulled the head to change all of the Schnider springs and retainers to Isky and found nicks on the pistons. Could have been valve float but I suspect the chain tensioner may have momentarily been over come by chain tension creating slack. I doubt the engine saw anything over 7500rpm that night, I doubt it went over 7k but it is possible. I have about 8000 miles on the build.

 

@bluestang the best I could do with SU's, L28, stock crank and flat top pistons 10.25 comp ratio, ported slovers N42 head was 191 rwhp with about 180 fpt. Very streetable, idle at 1000rpm.

 

Scott B

[200+ WHP NA build]

ScottB your post is Encouraging for me. I have a similar combo with DCOE40 and got similar rwhp peaking around 6800

 

My next venture was a planned upsize to 45s or Mikuni 44s or maybe GSXR ITB setup.

 

Good to know there might be some power there.

 

TJ

 

Good Luck TJ!

 

Tourque on the SU's was 180fp. I never ran 40mm DCOEs.

 

On the 45mm DCOE's the right venturi size makes a huge difference! Going from 34mm to 38mm gave a 16hp bump but had a small loss at 3000rpm. Thanks to Dave Rebello for the tip.

 

After reading Tony D's posts on the land speed car I'm wondering more about the benefits of ITB's. Wondering how much more power, if any, is possible. Of course dollar per HP gained at this point may not be worth it.

 

Scott B

[200+ WHP NA build]

Some combinations of parts work exceedingly well together, others don't. Scott's engine with 40's on it should easily pick up 20HP if not more from the reduced pumping losses on the intake side alone. Putting him within 24 HP of a 3.2 with 44's--you would THINK the big carbs and 3-400CC's would be worth more than that on the Benchracing Theoretical Scale!

 

AGAIN, it's the combination of parts, not picking numbers out of the air that are based on nothing more than theory. It doesn't work like that except on the benchracing interwebs.

 

In Scott's case, he came up with similar assumptions as you did. In the end talking with a head porter and a cam grinder he came up with a 2.8 at 0.040" over that twisted a set of SU's to 182 hp at the rear wheels at 6500 rpms or less with less CR than he thought he 'needed'.

 

 

 

 

I totally agree with Tony D's "it's the combination of parts", everything complements each other.

 

Details on my L2.8 build:

 

f54 L28 bored .020 over cast flat top pistons, stock crank, stock rods, arp rod bolts.

 

N42 head, stock valves, combustion chambers welded and ported by Slovers 44.1 cc chambers, Fel Pro head gasket.

 

Isky custom grind cam 540 lift, 270 duration. THANKS TONY D for the Isky tip!

 

Pacesetter 3 into 2 header with MSA 2 1/2in exhaust kit.

 

280zx distributor, MSD II coil.

 

10.25 to 1 comp ratio, 7000rpm red line, 91 octane gas.

 

SU's with SM needles made 190.7 at the wheels, on the same dyno and no changes except carbs,Weber 45's, 38mm chokes made 214.6 hp at the wheels and 198fp torque.

 

 

 

Honestly, this combo has far exceeded my expectations. It has a mellow idle at 1000rpm and pulls hard from 4400 to 7000. Super happy with it.

 

 

Scott B.