![]() ![]() They just found cars that were originally ordered in a street racer way. ![]() Mino's 68 Firebird was a lightweight, and so was Jensen's GT-37, but not "cheater" lightweight. It was hard to believe a little 400, rated at a measly 340 hp, or a low compression 455 rated at 335 hp, could beat up on on so many high compression, big cube, solid lifter cars, 400 + hp cars, but they did. It appeared as if they were cheating, but they weren't. Those guys had a firm understanding of the Pontiac drivetrain, head flow, etc., and spent a great deal of time and effort assembling their combos. In all honesty, I firmly believe that no one has really taken a RAIV to the same level that Mino took his RAII Firebird (or Jensen with his 455HO car). There has been a lot of speculation as to why the RAIV doesn't seem to do as well as the RAII and 455HO in the shootouts. On paper, the RAIV was a stronger combo.īut Jim Mino's 1968 RAII Firebirds seem to tell a different story. The RAII was basically a RAIV, but without the RAIV 1.65 high lift rocker arms, and without the nifty RAIV two-piece aluminum intake. ![]() The predecessor to the 1969 RAIV was the 1968-1/2 RAII. It was so effective, the camshaft is still widely used even today in Pontiac rebuilds, even with 35+ years of aftermarket cam grind technology available. The RAIV cam was the first computer designed camshaft in the industry. The 1971 455HO was essentially a low compression 455 RAIV, with round port heads and aluminum intake, and of course a much milder cam. But the 1971 455HO was nothing like the 1970 455HO. All the parts were in the parts bin, but Pontiac chose to stick with the RAIV 400.īy 1971, Pontiac was ready to unleash the RAIV 455, but with the compression ratio drop, they chose to drop the RAIV name and stick with the 455HO badge. Odd, because it was so incredibly easy to make the 455 version of the RAIV. Test engines of 455 based RAIV's were generating over 470 actual hp, but they would never see the light of day. The new management felt there was no simply need for a super high hp 455 when the 400 RAIV was doing just fine. DeLorean and Wangers left for Chevrolet in 1969, the RAV program was scrapped, and the PMD engineers were told there was virtually no development money left to create a RAIV 455 due to the enormous expense incurred in their failed RAV 303/400 program. Management problems, red tape, and corporate political wars came to a peak in 1970 at Pontiac. Pontiac dropped the ball in 1970 by not having a 455 RAIV ready. The 3.90 gears were standard on RAIV cars.Īs stated above, the 1970 455 HO was a d-port engine with a steel intake manifold. With the 1969 Firebird exhaust manifolds flowing a little better than the 1969 GTO's, and with the lighter Firebird weight, the peak of the Pontiac's 400 engine performance came in the 1969 Firebird RAIV, and yet those still used the 4-pinion HD 10-bolt. His goal was not to tweak or modify in any way, but to see what a RAIV truly produced, and lay to rest all the rumors about if the RAIV was really a 400 hp engine. A few years ago, Dan Jensen assembled an absolutely box stock RAIV engine for Musclecar Review, using all NOS parts (including the heads, cam, carb, etc). The 1969 RAIV was the pinnacle of the factory produced Pontiac 400 engines. I've always believed the saying: "there's no substitute for cubic inches". The compression was down in 71, but the 71 454/LS6 Vette was still able to muster 425 HP with low compression. I realize the popularity of Ram Air IV is in conjunction with the 69/70 Judges and the 455 wasn't available in a 69/70 Judge. It would seem that 455 HO is more comparable to the Chev 454/LS6 whereas the RA IV is comparable to a 396/L78. This reminds me of the GM ploy of manipulating HP rating like they did with the Chev L88, where GM under-rated the L88 by giving its rating at a lower RPM below it's peak RPM. When you look at motor ratings you see the factory rating of Ram Air IV Horsepower at 370HP/5500RPM, and the 455 HO at 360HP/4300RPM, which I wouldn't think is the 455's peak RPM. ![]() But obviously Pontiac Engineers recognized that 12-bolts were definitely needed due to the Torque and Horsepower in the 455's larger displacement motor. Still can't figure out why RA IV's didn't get 12 bolts though, when even SS350 Camaros got them. Ram Air IV motors seem to be regarded as top motor of choice in a Pontiac production car, but what about 455 HO motors? When you think about 400 Ram IV cars only having 10-bolt rears, and the 455 HO having a 12-bolt rear, there is significant difference. ![]()
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