Hello, I've been giving some deep thoughts to getting a new car. If I did it would be a speed density 350 TPI. I have a carbed 350 right now with all the stuff on it in my signature. I would like to know what I can swap over to the TPI motor... I don't think the cam and lifters because they are hydraulic flat tappet, and I believe the SD L98 is a roller? What about the heads and intake? Will they work on the newer block? Would it be pointless to put these heads on a stock L98 without upgrading the induction right away? I will eventually get into chip programming too, but not right away. Also, any recommendations on a cam that will work with the SD motor without giving me trouble? thanks, as you can tell I'm totally new to FI.

 

That all depends on what type of bolt holes are on the heads, in 87+ the bolt paterns on the intake n heads were chaged. You can tell by lookin at the valve covers. The new design uses centerbolt style vave covers. If your covers have perimeter bolts then no it wont work. No SD L98's were made b4 '90. And i think you are right about the camshaft too, sorry to be the bringer ov bad news.

 

I was just looking at all the fine print in the catalog, and it says "also available for 1987 to present engines with centerbolt valve covers and 2 center intake bolts at 72* angle." Does anyone know if it is possible to just have a machine shop drill the holes to make my heads work with a 1990 block? I have to have someone drill the holes for the coollant temp sensors anyway because I didn't get that done when I ordered them. Also, can anyone confirm or deny the info that the head bolt pattern itself is different?
John

P.S. are the starters different for 86 and earlier & 87 and later blocks too? Are the flywheels the same?

 

flywheel or flexplate is differnet due to rear main seal change at some point around 87.

 

The heads will bolt onto the block, no problem..the 72* intake holes refer to the center 4 holes holding the intake to the head. Since it'd seem you want a strong FI 350, most likely you'll end up using a aftermarket base and runners anyway, most I know of accept newer or older styled heads. If you have to keep the stock TPI intake, then the center holes can be elongated to work on your heads.

But you realize those AFr's are just junk anyways? You should just send them to me when you buy a new car, so I can melt hem down and add them to the Al. scrap pile out back.

 

lmao! Thanks for the (rather good!!) information. But I'm not gonna give ya my AFR's. If you want my car you can have it for a small fee. heh
John