351W stroker engine or not?

Hi there,

I´m interested in building a new engine for my GTD Mk1 and
therefore need to know if;

- there are anyone (I´v heard about a Rick Merz) who´s using a stroker engine bigger than 400 and that also can rpm to 7000 or even more?

- if there is someone of you guys out there that uses this setup of engine / or similar - please send me a specification over what parts you use and if you have noticed any specific troubles with this setup.

Hopeful,
Christoffer Lundgren
GTD-40 MK1
SWEDEN

The rod ratios on 351-based strokers (393,427, etc.) are not well suited for continuous high rpm usage. You can build strong bottom ends that can be pushed to that rpm range for a short period of time.

Yes the rod ratio is a concern as is the stroke which leads to high piston speeds. If you run a billet crank (e.g. NASCAR Oliver) and Rods it would easily live to 7000 RPM but this is expensive and would require a solid roller cam.

With the right heads you can make plenty of HP without going over 6500 RPM and can get away with a Hyd. roller cam.

If you want to turn the RPM's then you can go with a shorter stroke engine and a solid roller cam, but you will make less torque to obtain the desired HP.

If you look at my website you can see that a relatively high HP engine can be made at lower RPM with a hyd. roller cam equiped stroker.

I have a 351 stroked to 427 by Probe Industries. Another major problem with strokers is the piston pin violates the oil control ring lands. This causes excessive oil burning in fairly new engines. The probe motor solves this and they warranty the engine for 50K miles. With a mass air port injection system they claim 515HP with the same torque figure. Since mine has a hydraulic roller cam I am limited to 7000rpm. Probably more rpm than it will regularly see.

Mark

This piston pin issue is not a problem if the stroke is approximately 4" or below. My 428 CI is a 4.125 x 4". Some strokers of the same displacement are 4.030 x 4.17. I prefer the first combo which requires the use of a Dart block.