[60over68400]

I have been told two things with the RAIV cam that is in my car. That it makes power to 6500 and also to quote an email that I got from Rock N Roll Engineering "that cam isnt worth crap over 5500." So I am confused on this issue and I figured that if anybody can help me, then that would be the people on the forum. So tell me what you think. Could my stock rods handle that? sounds kinda high to me. thanks guys

[BILTIT]

I personally wouldn't go that high with stock rods, i like to stay around 5800 tops but thats just me. My 400 with RA4 cam and 670 heads seems to peeter out at about 5600 but it may be related to something else entirely. R&R has somewhat of a bad rap around this place.

[threefidee]

The problem you are most likely going to have is lack of flow out of your cylinder heads. My friend has a RA 4 motor which has been dynod and it does pull hard to 6,200 (after changing lifters as they will normally float at about 5,500). Keep in mind that is a RA 4 engine with RA 4 heads. Reving your motor over 5,500 rpm would probably just be slowing you down.

[67ConvFB]

I ran one in a 400 that ran best at 5,600 to 5,800 even with ported 48' s. I ran it up to 6,200 a couple of times at the track and it made no difference good or bad in ET.

[60over68400]

so maybe some ported heads? or some new lifters. I have stock rebuilt #16's with some 1.75 roller rockers with some comp cams push rods, with comp cams lifters

[60over68400]

i noticed that about R&R around here too. stopped me from buying some heads from them.

[johnsma22]

The factory red line is 5500 rpm for a reason. The stock rods will not live for long if they are run up over 5500 rpm consistantly. You will find no benifit in doing so anyway if the rest of the combo ie.. heads, intake, carb, exhaust, gears, ignition are not up to the task. If you are willing to address those other issues with the combo then you would most likely be installing forged rods anyway.

I learned about the bad rep that R&R has around here after I had already given them my money. I must be one of the "lucky" ones, because I had no problems.

John

[sixt8bird]

Interesting posts, but my findings about RPMs are a bit different from most. I have the 400 .030 over built stock with the exception of ballancing and TRW forged pistons. My heads have a qouick gasket match as does the headers. Im running stock 37 year old valves with new springs that now are 7 years old ant thats the extent. My RPMs dont slow down at any RPM. I quit at 6200 as I have stock rods. I race my car and have done 12.60 at 105.7 and I just did a 12.67 @ 107.1 and this is with stock heads and a smaller cam than the RAIV. 226-234 114 deg lobe sep. I actually tried shifting at 5500 and 5800 and slowed down so I think that stock heads can get air to squeeze through them pretty good without portwork. Just have no exhaust or intake restrictions. I actually did a 12.10 @ 112.4 on a small shot of Nitrous and then did another but spun and did a 12.24 @ 114.1 I will be in the 11s next with my combo. Non ported heads 400 engine.

[TCSGTO]

At one of the Supercar Showdowns I asked Jim Mino where he shifted his low 12 sec. bone stock 68 RAII Firebird. He said he never looked at the tach & just threw a rag over it and shifted by listening to the motor. He said if you did look at the tach the motor would be falling off at 5500.

[rdl]

Originally Posted by TCSGTO

... Jim Mino... where he shifted his low 12 sec. bone stock 68 RAII Firebird... the motor would be falling off at 5500.

FYI: Bear in mind that where a cam makes peak HP is not where you shift if you're drag racing. I'm a regular at the Pure Stock Drags. Mino was there 2 years ago (ran 12.5x), along with Tony Goodman. Goodman also campaigned a '68 R/A II Firebird at the event until this year. He ran quicker times(12.3x) than Mino and as I recall shifted somewhere in the range of 6,200 rpm. If you assume the 041 cam peaks at 5,500 rpm (in that application), then the higher shift point is about 10% above peak -- which is usually touted as the right point to hang the gear.

rdl

[Jim Mino]

FYI: Goodman's Firebird is (was) actually one of my former RAII clones that I restored, ran as a pure stock and sold (less engine). According to a feature in HPP, Goodman was running a 400 built to maxed-out NHRA specs, auto trans and a suspension optimized for racing on bias-ply tires. Also, bear in mind, according to the feature on his car, he wasn't running a RA IV cam or stock valve springs. So his 6200 RPM shifts are a moot point.

The Firebird I had at the Pure Stock Drags was a 4-speed car with no suspension mods, running a stock 400 with cast rods, 041 cam and stock valve springs. I've raced this set-up over 20 years and I do (occasionally) look at my tach. I've shifted these cars from 5500 to 6500 and everywhere in-between. 5800 seems to be about right for a stock 041 (RA IV) cam.

[Hard-Timess]

Jim, good to see you are still out there and hope to run with you sometime.

I am still campaigning HardTimes as a RA1 and RA2 in IHRA Pure Stock through FlowMaster single chamber mufflers with correct valves, springs, lifters and all cam specs (lift, duration/overlap).

We hold the B/PS record with the RA2 with 041 cam at 11.52 and this year with the RA1 with 068 cam in B/PS we ran 11.15 at Rockingham (3465lb) and 11.25 at Virginia in C/PS at 3520lb. We also took the RA1 Pure Stock car with mufflers to Gainsville and set the NHRA E/SA record to 11.35. This is with 4.33 gears, a 29.5 tire and 6600 rpm through the traps.

Like you, I have run stock "nodular iron" (not cast iron) rods to 6200-6600 rpm for over 37+ years and never had a problem (knock on wood). Bent one but never broke one. If the crank and rods are prepared correctly by a competent shop, they work. Anyone wanting to know more, email me at - fieldstd@verizon.net -

I have several engine combinations and 1968 Firebirds that I will be selling early 2006 from 400s to a fresh numbers matching 1972 455 HO - intake to pan with exhaust manifolds.

Respectfully, Truman Fields

[rdl]

Originally Posted by Jim Mino

FYI: Goodman's Firebird is (was) actually one of my former RAII clones that I restored, ran as a pure stock and sold (less engine).

Hello Jim! Good to see you post. I don't think we got a chance to meet, but I certainly admired your car up close (former and current copy). I'd forgotten that Goodman bought the car from you. The current owner ran 12.7x's with it this year. Clearly, driving has a lot to do with the number up on the board. Which brings me to your 12.5x's -- with a 4-speed -- simply outstanding!

Hope to perhaps meet next September? Cheers!

Rob