Debrue

Has anyone put 16v heads on a 5.0 block?

What HP and TQ numbers did you end up with over stock?

slate blue

https://rennlist.com/forums/928-foru...-thread-6.html

If you have a look from the top of the page and then continue downwards, you will see some of the changes I have made on the most basic of the four engines I am building, it is a 5.0 litre. The various tests are in different versions of the same capacity but minor changes like custom cams, custom intake manifold, or changes to ignition timing etc. this was before I had a aftermarket ecu that was able to tune precisely the air fuel ratio and ignition timing. So it is not fine tuned in these guises.

The dyno numbers would equate to just under 400 HP, I suspect 390 HP as other cars are factory rated around that number and get similar or slightly less rwhp numbers. There is a lot of devil in the detail to achieve these results and you can easily get less. I will be putting another engine together shortly so if you are interested keep an eye out. That engine though will use 104 mm pistons and standard stroke.

slate blue

I should add that the engine is being rebuilt with larger 48 mm Porsche valves from the 2.7 litre 944 and has increased head flow, I really think the head flow held it back and with that aspect improved in association with better tuning it will certainly be over 400 HP with very good torque. You could use many different aftermarket valves to do the same as I did with the Porsche valves.

Ducman82

Bolting stock euro 16v parts to a 5L block, fly cut Pistons.... I am in the 320hp rage....

85euro928

Is this at the rear wheels?

Debrue

also asking, is this rwhp?

Ducman82

Correction, 310 rwhp. I never did polish off the top end of the tune. For every 1 degree advancement in timing we were getting 1.2 more hours. But I ran out of dyno time and have been to busy. I am adding knock sensors so we shall see what that changes

danglerb

Typical for whats called a Euro hybrid, stock Euro top end on a stock US 85/86 bottom is 285 rwhp, its been done many times with fairly consistent results.

RFJ

Question,do you think adding 85-86 cams will do much for that?

mark kibort

Ive built 3 of these.... all still runing today. the Ljet makes 290 at the rear wheels (as compared to the 200 to 220baseline for a stock US 4.7L. one we did with CIS, and it made over 310rwhp. (torque was in the 290ish range)

all euro heads, and intake along with headers.

Mk

mark kibort

all of my builds were using the 85-86 2 valve cams or the euro 80-83 cams. all the euro stuff has the same lift... duration is slightly better with the 85086 cams.... using US cams would be anemic.

slate blue

I don't use the S2 Manifold, it has too an acute bend in it and airflow will suffer, I use the S manifolds or make my own per the link already provided.

Debrue

For an '81 5-spd with a 4.5L I am shopping a couple of ideas for power upgrade

1) buy a bolt-on supercharger or
2) toss the 4.5 for a 5.0 which will also mean some head/cam work will have to be done

I think costs are roughly the same between 1 and 2 and finished power will be similar.

For those of you who did the 5.0 swap why not a supercharger instead?

Debrue

mark kibort - do you have any youtube posts racing your car?

GlenL

Check your math and estimates. List the costs here so people can sanity-check them.