I'm looking into getting the Stealth Ram set up for my 350 TPI car Looking on input for the heads, I'm looking at the Corevtte aluminum L98 heads from GMPP, Would these heads work great with the Stealth Ram and a Hotcamshaft? Any other input on which heads to go with? Also on the camshaft would the GMPP 846 or 847 cam be a better choice than the hotcam, Thanks, Jason

 

The intake ports on the Stealth are much bigger geometrically than the GMPP Vette heads...I was running them when I initially did the Stealth Ram swap.

AFR 190 and Trick Flow 23deg heads are much closer out of the box, flow a lot better, and have more modern combustion chamber designs than the GMPP Vette heads. If power is your objective, save up a few more $$ and go with aftermarket.

A word of advice on the AFRs: if you go this route, I'd get perimeter-bolt valve cover machining and not the newer centerbolt. Much better selection of valve covers, no hacking to clear big roller rockers and guide plates, and easier to seal the valve covers. AFR puts the oil drainback hole much higher than GM, meaning the oil level is above the valve cover gasket during operation. A good set of perimeter bolt valve covers with load-distributing clamps will make keeping the oil inside much easier.

 

I agree to get some heads other than the L98s. They are a good head, but they are an old, out dated design. I did not think to get the perimeter style valve covers when I ordered my AFRs and I wish I had. Not only for rocker clearance, but for selection and price of valve covers on the market.

Does anyone know if the intake bolt pattern on the HSR is the same as stock? I mean does the HSR use the 72* center bolts like a stock base? Let me know. I think it does but am not sure.

 

Thanks, I think I'll go with the TrickFlow 23 degree heads, How about the camshaft the Hotcam or GMPP 846 camshaft? Thanks, Jason

 

My HSR has a pre 86 intake bolt pattern. I understand the later ones have oval holes to fit both patterns.

 

I'd consider the Comp Cams #305 cam over the HOT piece. Dunno the specs on the 846. Really depends on how you drive, your goal (emission compatibility, fuel economy, all-out performance...), and the car (rear gearing, transmission type and TC stall speed if applicable).

 

Get the larger valve springs for the TFS heads with either one of those cams. The 1.25 springs that come on the cheapest version of the TFS 23° heads have failed on a few members with less camshaft than that. I went with the 1.46 dual springs after having one of the top rounds of a TFS 1.25" valve spring break after only 1000 mild miles.

Do a search and you'll find where others had problems. Also, the $850.00 or so version of those heads are only rated at .525 lift and come with cheap stamped steel keepers, (and green at that).