Offshoreonly.com - Need engine advice N A 598 cubic inch rebuild

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Should've used a 741 cam. It's this decades 3/4 race cam from what I hear lol

Quote:

Originally Posted by lil red (Post 4242345)

Should've used a 741 cam. It's this decades 3/4 race cam from what I hear lol

Screw it. Let's go 12.5:1 with a 502 mag cam and some peanut ports. Should be great pump gas poker run engine. esp with a nice leftover mix of 6 month old gas come spring. Lock the timing at 38 and have fun. :drool1:

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Originally Posted by MILD THUNDER (Post 4242381)

:hitfan::crazy:

Quote:

Originally Posted by HaxbySpeed (Post 4242277)

S30, that's a pretty expensive set of heads to only make 740hp with. If that's all you were shooting for, the 325's out of the box would do it no problem.

Really
You've done this combo?what compr and rough cam spec?

Quote:

Originally Posted by lil red (Post 4242345)

Should've used a 741 cam. It's this decades 3/4 race cam from what I hear lol

Why is everyone so obsessed with using an RV cam? I mean at least use something that has a nice idle and doesn't sound like an RV...

Quote:

Originally Posted by fbc25el (Post 4242320)

Mr mayor, how was your service with your engine builder? I currently use a guy in indy but I am looking for a little closer shop. I met you a couple of years ago at Cumberland poker run we were at wolf creek with Tim & Terry. Fred.

Top notch

Quote:

Originally Posted by sutphen 30 (Post 4242393)

Really
You've done this combo?what compr and rough cam spec?

Yessir, 9.8 to 1, 89 octane, similar sized cam to what you're running, maybe a hair smaller. 2000cfm throttle body, Holley efi intake. It was a low rpm deal, made 770hp. I built a 600" with AFR 305's last year. I wouldn't try to argue with anyone that those are the right heads for a 600" motor, but it worked really well for it's application, and the throttle response was nothing short of violent. It made 705hp and 740 tq through a set of Dana's. I do a lot of engines for big white water jet boats that have a very narrow efficient rpm range so I experiment a lot with different combos. When the pump manufacturers are designing new impellers, they use a shaft dyno to calculate the KW absorption of the impeller. My dyno numbers always match the numbers in the boat. The 357's are a killer head, and a perfect match for a 598 if, in my opinion, you were shooting for 850-900hp. I was just saying that on an engine that mild, I couldn't see spending the money on them. I'd go with cheaper heads and buy shaft rockers instead. :)

https://youtube.com/watch?v=I1XC7qqFY9E

Quote:

Originally Posted by HaxbySpeed (Post 4242277)

S30, that's a pretty expensive set of heads to only make 740hp with. If that's all you were shooting for, the 325's out of the box would do it no problem.

Mayor, sounds like a great build, and is right where it should be on power with the components you used. Obviously there's a fair bit of power potential left with a cam swap, given the cubes and compression. But, realistically do you need any more? It will be a very reliable combo I'm sure.

Thanks and true for my boat and drive it is plenty and hope it last. I can't keep buying my wife anniversary gifts this expensive.

Quote:

Originally Posted by HaxbySpeed (Post 4242520)

how are you getting away with 89 octane at 9.8:1 without a "kaboom"?

I am running 10 to 1 on 89 - have for years. I only run 93 now because Sam's Club sells it for the same cost as 89. I do have the block zero decked. ( tight quench )