I would like to ask what cam specs are being used for 582 and 598 bracket engines set up for TBS 250 blowers. I have checked around for recommendations and there is a big difference in what was recommended.

Pick a cam grinder that you prefer, give the your engine specs and be detailed. Install the cam they provide where they say to install it and run it. Every engine is different, there is no set "spec" for an engine with a 250 blower. Someone can have the same engine size but due to some of the parts it might have, will require a different cam because of those parts.

I will preface by saying this is the same cam that was in the motor prior to adding the TBS 250. Motor is a 598 with same AFR 357 heads and the cam is a LSM .875/.833 282/296 with 1.75/1.70 rockers. Compression is at 13.5 and timing at 26*.

Yep same cam before and after the 250. Pick one that will make good natural power and you should be good.

285/302 850/830 113 LSA, made 1030 NA on 598, never been to dyno with the 250 but car went best of 4.75 @ 145 NA, and has been 4.32 162 with 250. 2100 lb with driver, 4 link dragster.

You'll make 8-10 psi on good days, more than likely you'll be in the 3-5 psi range for bad weather days.

Same cam in our 540 as when it was NA...don't have the card in front of me but similar to Triple Nickles, but our exhaust has less lift and duration.

Very happy with the combination, it's been 6.80/199 - 4.35/161 with a 31 pulley. Going to try the 29 later this year....

Weekly bracket racing we run a 35 pulley and it goes 7 teens and 4.50s very consistently.

quote:

Originally posted by Dragordie:
I would like to ask what cam specs are being used for 582 and 598 bracket engines set up for TBS 250 blowers. I have checked around for recommendations and there is a big difference in what was recommended.

I may get some flak for my input, but if you already have a known good cam that works well now NA I would use it.

I have a aluminum 5.3 ls with a 250 blower shop on it that was originally NA for 2 seasons-same camshaft, a 383 with 192 blower shop for my sons truck we are building-new camshaft, but I have knowledge of running this camshaft spec in other engines before, and my dragster with 582 F1R ProCharger has the same camshaft as it did when it was NA. Small camshaft in the .740 range and has been 4.10 so far in the 1/8. This camshaft had been a best of 4.55 in this 582 NA years ago and I just stayed with it as I knew it was the quickest camshaft for me in this engine I had tried over the years in it. Think I had tried 6 total in it.

If you're not putting the blower on for max effort ET and speed, but to merely "bring your own atmosphere" for bracket racing consistency, (a good plan in my opinion) I'd not bother to change anything of your N/A combo, except appropriate tune adjustments.