I understand that they have an appetite for valve springs.Is this just due to the crazy cam profiles?Can the valve spring life be improved with a less radical profile?

Yep, they like lots of spring pressure and big cam profiles. We tried a small cam (.980ish lift, and it fell on its face, on the dyno) Be prepared to spend lots of money, if you are going to take the plunge.

We were able to get 15 ish Truck pulling runs out of our 5" 99 engine. But since were at 650ci we could run lower rpm's. 8000-9000rpm.

But with any engine at these level of hp and RPM valve spring maintenance becomes as common as checking your valve lashe.

there was a morgan 99 block,with studs and machining mostly done for 1500 on ebay,and a new set of bare 99 unmachined pro stock heads for 795.00 obo.toss in another 25 grand and bada-bing,almost go racing

Then add 50 grand and viola you have a complete one

absolutely!!!! but then theres the 12 grand clutch and the trans too.although,i DID see a complete j and j 99 motor for 10 grand,1400 hp.on racinjunk,guy was hurting for money I believe,said its been sitting in his shop for a year or two,just looked and its gone...oh well,somebody got a deal.............

We actually went an entire season on the saem exhaust springs with the 99. The intakes were good for 20ish runs as long as it stayed under 10500 rpm. They are killer pieces but very much purpose built. They take RPM to work but if you are not afraid of that they are defintely the class of the Mopar field.

Used, or experienced stuff is not as plentiful as it once was. There are things to avoid, the older two bolt heads, 5 cam blocks, so far the symetrical port stuff has not proven to be up the the older asymetric stuff. Which might explain the shortage of the later asymetric stuff lately. They are VERY heavy engines as well. The generally use spindly inards. Small rod journals and, so not much bearing and usually very thin ring pack. All this stuff leads to more power but also to a more constant need for maintenance.

We were going to run one in Top Sportsman but I recently decided to go to a new set up that we can also throw a power adder at if need be. I think in a lighter car, with big tires and a 4 or 5 speed they would be the shiznit.

There is one in Cali for sale that is 550" and built by Larry Morgan. I have seen it run and the car runs well. His asking price is .50 on the dollar. Also as previsouly pointed out here the deal Diablo has is an awesome deal. Had I not just started my new deal it would already be headed my way.

appears to be fantastic stuff,but just like the nascar motor exotic goodies,very costly.technically,theres cheaper used sonnys motors floating around ,maybe if and when the market gets flooded,the cost of racing a 99 will become average joe accessable......

We just started yesterday. Al's help is appreciated.

Are the ports the biggest issue? Too much port for the engine size such that RPM is the only way to harness it. Just curious

Thanks for the replys fellas heaps of helpful info.I'm pretty much a hobo and for the last 20 yrs all i've been able to afford is junk stroker vws(fastest daily in oz)I'm sure it will see me broke going down this route but fun and fast.Im gonna have more questions from the above info .I'd be happy with 800 hp,i know that can be acheived other ways but lets say i know a dude.I'll get back here later today gotta busy sunday morning.thanks again guys.

Work with someone who has experience with Pro Stock or Super Stock/ Comp Eliminator engines if you can. An engine like this will have a steep learning curve learning it yourself. There are a lot of tricks that go into an engine of this caliber, things generally just not known by builders with experience in more conventional builds.

Al,whats the problems associated with the 2 bolt heads and 5cam block(5cam bearings im guessing?),