nick_n_ii

Ok I'm starting to look for parts for a engine build for a spring swap.

Now I have a renix 4.0.

Can I bolt the renix intake onto a HO 4.0?

Can I build a HO 4.0 with HO intake and just re-drill it to except the Renix throttle body?

Looking for best bang for buck with out building it as a stroker. The goal is for a motor some where between a 4.2 to 4.4. Done all with bore.

The idea in my head (not sure if it would work) is. Use a HO 4.0 with a 99+ intake redrilled to except the Renix throttle body. Mild cam, Boral header and bored out.

Thanks, Idea's. Am I just nuts?

Need some input on this for when I start looking for parts.

ol"blue

From the short time I've been here I haven't seen any reason your plans won't work. The intake mounting flange had a slight difference but will work, according to what I've read. I'd raise the compression a little to compensate for the larger quench area from the bigger bore. JMO

nick_n_ii

Well glad to see I'm not far off in my thinking.

I figure everyone else is building strokers, I want something different..

ol"blue

In racing, a stroker engine has always been more for higher RPMs. Whereas a big bore engine is more for lower RPM power. I think you've got a great idea and plan.
Dan

nick_n_ii

Yep, same as in ATV's and Dirt Bikes. Kinda where the whole idea started from..

Donnie_K

huh? longer stroke with a smaller bore = More Torque and pulling power... Shorter stroke with a bigger bore means higher RPM's/Higher Redline.

EndlessMtnFab

The ports are different heights between the 2 styles of motors. You would have to do some porting work to make them match.


Actually, you would have a perf. machine shop do it. Just grinding and shaping without regards to air flow would actually make less power (not more). A good shop should be able to do the work without needing a flow bench. The flow bench will confirm the areas of high/low flow for a machinist that might not be familiar with the characteristics of our heads. I have done some port matching on other heads with a flow bench in the past. Very interesting technique & concept. Takes time & patience. So don't expect a cheap job.


You would have to do some surface machining to allow the Renix TB to sit on the HO manifold. The shapes are different and you need a flat mating surface. Additionally, you will need to plug the HO bolt pattern and redrill the Renix pattern. Don't forget to make provisions for the EGR in the manifold.


The minimum size "stroker" you will get would be 4.5 cubic inches. That would be with no cylinder overbore and the 4.2 crank. The 4.6 is the most common size because of the .030 overbore to clean up the cylinder walls.


In terms of simplicity ... it would probably be better to have a machine shop work your existing Renix head (reshape the curves, port matching, 3 angle valve job, back cut valves) to gain the flow you want. You'll be slightly limited by the intake unless you put some money into that as well. But let's be realistic ... you only have a 5,000 RPM limit. Not like you're going to move THAT much air.



Joe

nick_n_ii

Thanks for the input.

And keep any info about that coming.

I think my main direction is to make a HO motor (built a way I choice) work with a Renix TB and computer..