I have an M6 car with the 227/233 cam with 1.6rr, and mildly worked stock heads. Full exhaust, 4.10 gears, CAI, AFPR, full bolt on, you know the deal. This question seems often contemplated, but I am looking for some real dyno numbers or track gains for this mod- adding a 52mm or 58 mm throttle body. Has anyone seen any realworld gains with a similar cam???

 

Hopefully I will be able to have a comparison within the next month or so.

 

I have a similar set-up to yours with the mildly ported heads, headers, 4.10 gears, 1.6 roller rockers and the bolts ons but my cam is smaller 218/224, the car made 306rwhp/318rwtq on the dyno with a mail order tune. I put on a 52mm throttle body (edelbrock), 160t-stat and had the car dyno tuned and it made 321rwhp and 324rwtq. I'm not sure how much of the gain was from the larger throttle body but the power gain was noticeable and it felt more powerful in the top end.

I am looking at putting in a larger cam and was wondering the full specs on the cam you are using and how it runs (idle quality and does it have any cam surge) does it pass emissions and what type of power it makes. Thanks.

 

The 227/233 has 560/569 lift with roller rockers. Mine is ground on a 112 lsa. The idle is choppy, but sounds good. I have very little Cam surge thanks to PCM for less tune. I really like this cam. It makes awesome power up top, and I have no problem with low end power either. I havent dynoed it, so cant give you any numbers. As far as emissions go, dont have to worry about that in my area, but I dont know if you could get that cam to pass a sniffer test. You would def. have to have someone do an emissions tune, and have some luck in your favor.

 

In my opinion, you need a 52 mm TB.