How much boost can the con rods handle

[ajm55]

I gather that the con rods are the weak link when turning up boost. Anyone know where the limit is (in terms of boost) before you'll risk bending a rod?

[M5_Raz]

Nobody knows. People bend rods on stock power too. It's all about driving style, oil change intervals, etc.

At the same time there's people that have been stage 2 for 50k+ miles without any issues.

[ajm55]

Originally Posted by M5_Raz

Nobody knows. People bend rods on stock power too. It's all about driving style, oil change intervals, etc.

At the same time there's people that have been stage 2 for 50k+ miles without any issues.

Thanks. When it comes to driving style, I assume that one should not go WOT beneath about 3,500 rpm?

[M5_Raz]

Yep, exactly. No full throttle at low rpm and a slow warmup are crucial. Also frequent oil changes at max 5k miles and checking the level often based on how much yours burns.

With all the horror stories you read I've decided to run full bolt ons on a modified stock tune (no cold start, no check engine light for downpipes, no top speed limiter) just to keep it reliable.

[ajm55]

Sounds sensible. I'm anal about getting things right. Too costly to repair when things break. When you say full bolt-ons, what besides downpipes do you have on yours. I do oil changes annually (which is within 5,000kms of distance travelled) and I'm running a mild-ish tune with dps and upgraded charge coolers - around 900nm and 480 wkw. Luckily mine uses no oil between oil changes but that's probably attributable (at least, in part) to the fact that I change oil in very short intervals

[fstm5]

Originally Posted by M5_Raz

Yep, exactly. No full throttle at low rpm and a slow warmup are crucial. Also frequent oil changes at max 5k miles and checking the level often based on how much yours burns.

With all the horror stories you read I've decided to run full bolt ons on a modified stock tune (no cold start, no check engine light for downpipes, no top speed limiter) just to keep it reliable.

Curious, can you elaborate on not going WOT in low rpm's, are we talking high gear low speeds WOT or accelerating from first gear WOT

[M5_Raz]

Originally Posted by ajm55

Sounds sensible. I'm anal about getting things right. Too costly to repair when things break. When you say full bolt-ons, what besides downpipes do you have on yours. I do oil changes annually (which is within 5,000kms of distance travelled) and I'm running a mild-ish tune with dps and upgraded charge coolers - around 900nm and 480 wkw. Luckily mine uses no oil between oil changes but that's probably attributable (at least, in part) to the fact that I change oil in very short intervals

Same here, but mine burns about a quart per 1500 miles. Probably because I use a lighter oil than some (M1 0w-40).

As for mods, I'm pretty much the same. 90mm downpipes (bigger than the usual 76mm), full titanium exhaust, front mounted intakes, wrapped coolant lines, and I'm waiting for charge coolers to be back in stock.

[M5_Raz]

Originally Posted by fstm5

Curious, can you elaborate on not going WOT in low rpm's, are we talking high gear low speeds WOT or accelerating from first gear WOT

Both. When moving I only go full throttle at 4k+ rpm and from a stop I ease into it. I don't do much full throttle from 0 and always with mdm on so it allows the car to fishtail.