tedesco

Hallo,

I am new to the 928 scene and do not own one jet but I have a few 944s which are the starting point for my questions. It is quite simple to extract around 400 RWHP from a 944 turbo. So I was wondering if in case of a 928 it would be twice that much with twice the expense? I heard quite often about blocks cracking and that they woun´t last. From the 944 I am not used to that. The engines are absolutly bullet proved. What kind of troubles do you expect for a 928 twin turbo set up (besides that you have to do all yourselfe, no kits...)?

John Veninger

Search the board on supercharger and also turbo. Be ready to spend hours reading. There are kits out there from $5K-$7K to give you 400rwhp+

Blocks cracking, nope.

Brett928S2

Hi

With my Nitrous kit...I am approaching 500 hp with no engine problems at all

All the best Brett

Vilhuer

951 blocks are somewhat stronger than 928 blocks. 928 block isn't too bad though and should not crack very easily unless piston size is increased too much.

tedesco

Thanks, that is good news. I heard that the blocks would crack somewhere in the V between the cylinder banks. On my 944 I do already about 400RWHP so I was thinking twice the cylinders same technique as on 944 results in double the fun (and unfortunatly $$$ too).

Did only a quick search before but the recent post did not seem very productive for the information I was looking for. I will have a closer look!

jyoon

don't expect even close to double the power of a 951 from a 928. also, 400 rwhp on a 951 requires quite a bit of modifications. i think to reach that power level, you're going way beyond the simple turbo, maf, injectors etc and it's gonna cost considerable $$$. i would consider the 951 engine definitely not bulletproof.

tedesco

If I will start that project than certainly in a propper way. On the 951 it needed turbo, injectors, MAF (but now I would go stand alone ECU), Rods, Pistons, exhaust, fuel pump, Oil galerie change and a lot of other details + general rebuild. It was not cheap on the 944 and I don´t expect it to be cheaper on a 928. They all come in NA from which means at least new exh. valves + cooling issues...
But why would it be hard to double the power with twice the cylinders? This is exactly the point where I need your experience. My simple thinking was that the 944 engine was born from the 928 and in fact quite a lot of parts are compatible. So where do you expect problems to arise if I would just dublicate my 951 setting for 400RWHP? i would not go this way fro something in the range of 500HP. Will be still a blistering fast car but also 200kg heavier than my 951.

Larry928GTS

I've never heard of one doing that. Has anyone else? If so, any additional information on it?

jyoon

the tranny and drivetrain will probably not handle the power you would like. also, since the 928 was not originally boosted, the cylinder towers are thinner and less rigid that the 951. i would think a moderate amount of boost and around 500hp or so in a 928 would be a much better driving car than a 400 hp 2.5 turbo 4 cylinder. i have both a turbo S and a 928 euro. the 928 is much funner to drive around town. it gets off the line fast and you don't have to be at 3500rpm's or so to get moving. ultimately, i think my 928 would easily outlast my 951.